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  • richardmitnick 4:15 pm on July 13, 2021 Permalink | Reply
    Tags: "Galactic gamma ray bursts predicted last year show up on schedule", FRB's Fast radio Bursts, Magnetars: massive spinning neutron stars with magnetic fields among the most powerful known., NASA Wind Spacecraft, SGR1935+2154: a soft gamma repeater that is a magnetar., Soft gamma repeaters, Supernova Cosmology Project based at DOE's Lawrence Berkeley National Laboratory.,   

    From University of California-Berkeley (US) : “Galactic gamma ray bursts predicted last year show up on schedule” 

    From University of California-Berkeley (US)

    July 13, 2021
    Robert Sanders
    rlsanders@berkeley.edu

    1
    An artist’s depiction of a hiccup in the magnetic field of a magnetar — a highly magnetized neutron star — that produces a powerful gamma ray burst visible from across the galaxy. UC Berkeley physicists have found an unusual pattern to these bursts that could help pin down the precise mechanism triggering the hiccups and generating the soft gamma bursts. Image courtesy of Chris Smith/ NASA’s Goddard Space Flight Center/Universities Space Research Association/Goddard Earth Science Technology and Research] (US)).

    Magnetars are bizarre objects — massive spinning neutron stars with magnetic fields among the most powerful known, capable of shooting off brief bursts of radio waves so bright they’re visible across the universe.

    Iconic depiction of Magnetar in Westerlund 1 Credit: L.Calçada/ESO.

    A team of astrophysicists has now found another peculiarity of magnetars: They can emit bursts of low energy gamma rays in a pattern never before seen in any other astronomical object.

    It’s unclear why this should be, but magnetars themselves are poorly understood, with dozens of theories about how they produce radio and gamma ray bursts. The recognition of this unusual pattern of gamma ray activity could help theorists figure out the mechanisms involved.

    “Magnetars, which are connected with fast radio bursts and soft gamma repeaters, have something periodic going on, on top of randomness,” said astrophysicist Bruce Grossan, an astrophysicist at the University of California, Berkeley’s Space Sciences Laboratory (SSL). “This is another mystery on top of the mystery of how the bursts are produced.”

    The researchers — Grossan and theoretical physicist and cosmologist Eric Linder from SSL and the Berkeley Center for Cosmological Physics and postdoctoral fellow Mikhail Denissenya from Nazarbayev University [Nazarbaev Únıversıteti](KZ) in Kazakhstan — discovered the pattern last year in bursts from a soft gamma repeater, SGR1935+2154, that is a magnetar, a prolific source of soft or lower energy gamma ray bursts and the only known source of fast radio bursts within our Milky Way galaxy. They found that the object emits bursts randomly, but only within regular four-month windows of time, each active window separated by three months of inactivity.

    On March 19, the team uploaded a preprint claiming “periodic windowed behavior” in soft gamma bursts from SGR1935+2154 and predicted that these bursts would start up again after June 1 — following a three month hiatus — and could occur throughout a four-month window ending Oct. 7.

    On June 24, three weeks into the window of activity, the first new burst from SGR1935+2154 was observed after the predicted three month gap, and nearly a dozen more bursts have been observed since, including one on July 6, the day the paper was published online in the journal Physical Review D.

    “These new bursts within this window means that our prediction is dead on,” said Grossan, who studies high energy astronomical transients. “Probably more important is that no bursts were detected between the windows since we first published our preprint.”

    Linder likens the non-detection of bursts in three-month windows to a key clue — the “curious incident” that a guard dog did not bark in the nighttime — that allowed Sherlock Holmes to solve a murder in the short story The Adventure of Silver Blaze.

    “Missing or occasional data is a nightmare for any scientist,” noted Denissenya, the first author of the paper and a member of the Energetic Cosmos Laboratory at Nazarbayev University that was founded several years ago by Grossan, Linder and UC Berkeley cosmologist and Nobel laureate George Smoot. “In our case, it was crucial to realize that missing bursts or no bursts at all carry information.”

    The confirmation of their prediction startled and thrilled the researchers, who think this may be a novel example of a phenomenon — periodic windowed behavior — that could characterize emissions from other astronomical objects.

    Mining data from 27-year-old satellite

    Within the last year, researchers suggested that the emission of fast radio bursts — which typically last a few thousandths of a second — from distant galaxies might be clustered in a periodic windowed pattern. But the data were intermittent, and the statistical and computational tools to firmly establish such a claim with sparse data were not well developed.

    1
    Since 2014, a magnetar in our galaxy (SGR1935+2154) has been emitting bursts of soft gamma rays (black stars). UC Berkeley scientists concluded that they occurred only within certain windows of time (green stripes) but were somehow blocked during intervening windows (red). They used this pattern to predict renewed bursts starting after June 1, 2021 (stripes outlined in blue at right), and since June 24, more than a dozen have been detected (blue stars): right on schedule. Graphic by Mikhail Denissenya.

    Grossan convinced Linder to explore whether advanced techniques and tools could be used to demonstrate that periodically windowed — but random, as well, within an activity window — behavior was present in the soft gamma ray burst data of the SGR1935+2154 magnetar. The Konus instrument aboard the WIND spacecraft, launched in 1994, has recorded soft gamma ray bursts from that object — which also exhibits fast radio bursts — since 2014 and likely never missed a bright one.

    NASA Wind Spacecraft

    Linder, a member of the Supernova Cosmology Project based at DOE’s Lawrence Berkeley National Laboratory, had used advanced statistical techniques to study the clustering in space of galaxies in the universe, and he and Denissenya adapted these techniques to analyze the clustering of bursts in time. Their analysis, the first to use such techniques for repeated events, showed an unusual windowed periodicity distinct from the very precise repetition produced by bodies rotating or in orbit, which most astronomers think of when they think of periodic behavior.

    “So far, we have observed bursts over 10 windowed periods since 2014, and the probability is 3 in 10,000 that while we think it is periodic windowed, it is actually random,” he said, meaning there’s a 99.97% chance they’re right. He noted that a Monte Carlo simulation indicated that the chance they’re seeing a pattern that isn’t really there is likely well under 1 in a billion.

    The recent observation of five bursts within their predicted window, seen by WIND and other spacecraft monitoring gamma ray bursts, adds to their confidence. However, a single future burst observed outside the window would disprove the whole theory, or cause them to redo their analysis completely.

    “The most intriguing and fun part for me was to make predictions that could be tested in the sky. We then ran simulations against real and random patterns and found it really did tell us about the bursts,” Denissenya said.

    As for what causes this pattern, Grossan and Linder can only guess. Soft gamma ray bursts from magnetars are thought to involve starquakes, perhaps triggered by interactions between the neutron star’s crust and its intense magnetic field. Magnetars rotate once every few seconds, and if the rotation is accompanied by a precession — a wobble in the rotation — that might make the source of burst emission point to Earth only within a certain window. Another possibility, Grossan said, is that a dense, rotating cloud of obscuring material surrounds the magnetar but has a hole that only periodically allows bursts to come out and reach Earth.

    “At this stage of our knowledge of these sources, we can’t really say which it is,” Grossan said. “This is a rich phenomenon that will likely be studied for some time.”

    Linder agrees and points out that the advances were made by the cross-pollination of techniques from high energy astrophysics observations and theoretical cosmology.

    “UC Berkeley is a great place where diverse scientists can come together,” he said. “They will continue to watch and learn and even ‘listen’ with their instruments for more dogs in the night.”

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The University of California-Berkeley US) is a public land-grant research university in Berkeley, California. Established in 1868 as the state’s first land-grant university, it was the first campus of the University of California (US) system and a founding member of the Association of American Universities (US). Its 14 colleges and schools offer over 350 degree programs and enroll some 31,000 undergraduate and 12,000 graduate students. Berkeley is ranked among the world’s top universities by major educational publications.

    Berkeley hosts many leading research institutes, including the Mathematical Sciences Research Institute and the Space Sciences Laboratory. It founded and maintains close relationships with three national laboratories at DOE’s Lawrence Berkeley National Laboratory(US), DOE’s Lawrence Livermore National Laboratory(US) and DOE’s Los Alamos National Lab(US), and has played a prominent role in many scientific advances, from the Manhattan Project and the discovery of 16 chemical elements to breakthroughs in computer science and genomics. Berkeley is also known for student activism and the Free Speech Movement of the 1960s.

    Berkeley alumni and faculty count among their ranks 110 Nobel laureates (34 alumni), 25 Turing Award winners (11 alumni), 14 Fields Medalists, 28 Wolf Prize winners, 103 MacArthur “Genius Grant” recipients, 30 Pulitzer Prize winners, and 19 Academy Award winners. The university has produced seven heads of state or government; five chief justices, including Chief Justice of the United States Earl Warren; 21 cabinet-level officials; 11 governors; and 25 living billionaires. It is also a leading producer of Fulbright Scholars, MacArthur Fellows, and Marshall Scholars. Berkeley alumni, widely recognized for their entrepreneurship, have founded many notable companies.

    Berkeley’s athletic teams compete in Division I of the NCAA, primarily in the Pac-12 Conference, and are collectively known as the California Golden Bears. The university’s teams have won 107 national championships, and its students and alumni have won 207 Olympic medals.

    Made possible by President Lincoln’s signing of the Morrill Act in 1862, the University of California was founded in 1868 as the state’s first land-grant university by inheriting certain assets and objectives of the private College of California and the public Agricultural, Mining, and Mechanical Arts College. Although this process is often incorrectly mistaken for a merger, the Organic Act created a “completely new institution” and did not actually merge the two precursor entities into the new university. The Organic Act states that the “University shall have for its design, to provide instruction and thorough and complete education in all departments of science, literature and art, industrial and professional pursuits, and general education, and also special courses of instruction in preparation for the professions”.

    Ten faculty members and 40 students made up the fledgling university when it opened in Oakland in 1869. Frederick H. Billings, a trustee of the College of California, suggested that a new campus site north of Oakland be named in honor of Anglo-Irish philosopher George Berkeley. The university began admitting women the following year. In 1870, Henry Durant, founder of the College of California, became its first president. With the completion of North and South Halls in 1873, the university relocated to its Berkeley location with 167 male and 22 female students.

    Beginning in 1891, Phoebe Apperson Hearst made several large gifts to Berkeley, funding a number of programs and new buildings and sponsoring, in 1898, an international competition in Antwerp, Belgium, where French architect Émile Bénard submitted the winning design for a campus master plan.

    20th century

    In 1905, the University Farm was established near Sacramento, ultimately becoming the University of California, Davis. In 1919, Los Angeles State Normal School became the southern branch of the University, which ultimately became the University of California, Los Angeles. By 1920s, the number of campus buildings had grown substantially and included twenty structures designed by architect John Galen Howard.

    In 1917, one of the nation’s first ROTC programs was established at Berkeley and its School of Military Aeronautics began training pilots, including Gen. Jimmy Doolittle. Berkeley ROTC alumni include former Secretary of Defense Robert McNamara and Army Chief of Staff Frederick C. Weyand as well as 16 other generals. In 1926, future fleet admiral Chester W. Nimitz established the first Naval ROTC unit at Berkeley.

    In the 1930s, Ernest Lawrence helped establish the Radiation Laboratory (now DOE’s Lawrence Berkeley National Laboratory (US)) and invented the cyclotron, which won him the Nobel physics prize in 1939. Using the cyclotron, Berkeley professors and Berkeley Lab researchers went on to discover 16 chemical elements—more than any other university in the world. In particular, during World War II and following Glenn Seaborg’s then-secret discovery of plutonium, Ernest Orlando Lawrence’s Radiation Laboratory began to contract with the U.S. Army to develop the atomic bomb. Physics professor J. Robert Oppenheimer was named scientific head of the Manhattan Project in 1942. Along with the Lawrence Berkeley National Laboratory, Berkeley founded and was then a partner in managing two other labs, Los Alamos National Laboratory (1943) and Lawrence Livermore National Laboratory (1952).

    By 1942, the American Council on Education ranked Berkeley second only to Harvard University (US) in the number of distinguished departments.

    In 1952, the University of California reorganized itself into a system of semi-autonomous campuses, with each campus given its own chancellor, and Clark Kerr became Berkeley’s first Chancellor, while Sproul remained in place as the President of the University of California.

    Berkeley gained a worldwide reputation for political activism in the 1960s. In 1964, the Free Speech Movement organized student resistance to the university’s restrictions on political activities on campus—most conspicuously, student activities related to the Civil Rights Movement. The arrest in Sproul Plaza of Jack Weinberg, a recent Berkeley alumnus and chair of Campus CORE, in October 1964, prompted a series of student-led acts of formal remonstrance and civil disobedience that ultimately gave rise to the Free Speech Movement, which movement would prevail and serve as precedent for student opposition to America’s involvement in the Vietnam War.

    In 1982, the Mathematical Sciences Research Institute (MSRI) was established on campus with support from the National Science Foundation and at the request of three Berkeley mathematicians — Shiing-Shen Chern, Calvin Moore and Isadore M. Singer. The institute is now widely regarded as a leading center for collaborative mathematical research, drawing thousands of visiting researchers from around the world each year.

    21st century

    In the current century, Berkeley has become less politically active and more focused on entrepreneurship and fundraising, especially for STEM disciplines.

    Modern Berkeley students are less politically radical, with a greater percentage of moderates and conservatives than in the 1960s and 70s. Democrats outnumber Republicans on the faculty by a ratio of 9:1. On the whole, Democrats outnumber Republicans on American university campuses by a ratio of 10:1.

    In 2007, the Energy Biosciences Institute was established with funding from BP and Stanley Hall, a research facility and headquarters for the California Institute for Quantitative Biosciences, opened. The next few years saw the dedication of the Center for Biomedical and Health Sciences, funded by a lead gift from billionaire Li Ka-shing; the opening of Sutardja Dai Hall, home of the Center for Information Technology Research in the Interest of Society; and the unveiling of Blum Hall, housing the Blum Center for Developing Economies. Supported by a grant from alumnus James Simons, the Simons Institute for the Theory of Computing was established in 2012. In 2014, Berkeley and its sister campus, Univerity of California-San Fransisco (US), established the Innovative Genomics Institute, and, in 2020, an anonymous donor pledged $252 million to help fund a new center for computing and data science.

    Since 2000, Berkeley alumni and faculty have received 40 Nobel Prizes, behind only Harvard and Massachusetts Institute of Technology (US) among US universities; five Turing Awards, behind only MIT and Stanford; and five Fields Medals, second only to Princeton University (US). According to PitchBook, Berkeley ranks second, just behind Stanford University, in producing VC-backed entrepreneurs.

    UC Berkeley Seal

     
  • richardmitnick 7:52 am on June 11, 2021 Permalink | Reply
    Tags: "June Grad Student of the Month: Amanda Cook, , , FRB's Fast radio Bursts, Measuring the extent of the plasma in the Milky Way using FRBs., , Women in STEM-Amanda Cook   

    From Dunlap Institute for Astronomy and Astrophysics (CA) :Women in STEM-Amanda Cook “June Grad Student of the Month: Amanda Cook 

    From Dunlap Institute for Astronomy and Astrophysics (CA)

    At

    University of Toronto (CA)

    6.2.21

    1
    Amanda is a second year PhD student at the University of Toronto, specializing in Astrostatistics. Before U of T, Amanda received an Honours Mathematics and Physics degree from McGill University (CA), and held summer research positions at NASA JPL (US) and the Kyoto University [京都大学](JP).

    How did you first become interested in Astronomy and Astrophysics?

    I feel a great sense of wonder and awe gazing into the night sky, and I have ever since I was a child. But I must admit, I was actually interested in the physical sciences more broadly initially, since – like most of the graduate students here – I excelled in math and physics in grade school. I think my path was cemented in astrophysics specifically by all the inspiring women I had as role models and mentors during my undergraduate degree. I could really see myself being happy and supported in this field.

    Can you tell us a little bit about your specific field of research?

    I am most interested in transient astrophysics. Lately I’ve been working on learning more about mysterious “Fast Radio Bursts”, or FRBs. FRBs are super bright radio flashes from distant galaxies, and astronomers do not know what is causing them yet. I am a part of a great team on the Canadian experiment called CHIME/FRB which has discovered hundreds of new FRBs.

    So I’m interested in harnessing the statistical power of that large sample to learn more about FRBs as well as use them as probes of the plasma they travel through.

    What’s the most exciting thing about your research?

    Right now I am trying to measure the extent of the plasma in the Milky Way using FRBs. It’s so cool to be starting to resolve the ‘edge’ of our Galaxy, which is too distant for us to ever visit, using these enigmatic signals that were emitted millions of years ago. And all of this is being accomplished using a telescope in BC and doing analysis from my living room. More generally though I think the most exciting part is waking up and knowing that at any moment we could make a new discovery or put together another piece of the FRB puzzle. The feeling among colleagues when something game-changing is found is truly one of the best parts of this job.

    What do you hope will be your next step, professionally?

    I hope to go on to be an astrophysicist, the typical next step after a PhD is to be a post-doctoral researcher. It has always been my dream to make a career out of discovery, learning, and teaching. As for this moment, I’m focusing on passing all my qualifying exams and publishing my first research paper.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.


    Stem Education Coalition

    Dunlap Institute campus

    The Dunlap Institute for Astronomy & Astrophysics (CA) at University of Toronto (CA) is an endowed research institute with nearly 70 faculty, postdocs, students and staff, dedicated to innovative technology, ground-breaking research, world-class training, and public engagement. The research themes of its faculty and Dunlap Fellows span the Universe and include: optical, infrared and radio instrumentation; Dark Energy; large-scale structure; the Cosmic Microwave Background; the interstellar medium; galaxy evolution; cosmic magnetism; and time-domain science.

    The Dunlap Institute (CA), University of Toronto Department of Astronomy & Astrophysics (CA), Canadian Institute for Theoretical Astrophysics (CA), and Centre for Planetary Sciences (CA) comprise the leading centre for astronomical research in Canada, at the leading research university in the country, the University of Toronto (CA).

    The Dunlap Institute (CA) is committed to making its science, training and public outreach activities productive and enjoyable for everyone, regardless of gender, sexual orientation, disability, physical appearance, body size, race, nationality or religion.

    Our work is greatly enhanced through collaborations with the Department of Astronomy & Astrophysics (CA), Canadian Institute for Theoretical Astrophysics (CA), David Dunlap Observatory (CA), Ontario Science Centre (CA), Royal Astronomical Society of Canada (CA), the Toronto Public Library (CA), and many other partners.

    The University of Toronto(CA) is a public research university in Toronto, Ontario, Canada, located on the grounds that surround Queen’s Park. It was founded by royal charter in 1827 as King’s College, the oldest university in the province of Ontario.

    Originally controlled by the Church of England, the university assumed its present name in 1850 upon becoming a secular institution.

    As a collegiate university, it comprises eleven colleges each with substantial autonomy on financial and institutional affairs and significant differences in character and history. The university also operates two satellite campuses located in Scarborough and Mississauga.

    University of Toronto has evolved into Canada’s leading institution of learning, discovery and knowledge creation. We are proud to be one of the world’s top research-intensive universities, driven to invent and innovate.

    Our students have the opportunity to learn from and work with preeminent thought leaders through our multidisciplinary network of teaching and research faculty, alumni and partners.

    The ideas, innovations and actions of more than 560,000 graduates continue to have a positive impact on the world.

    Academically, the University of Toronto is noted for movements and curricula in literary criticism and communication theory, known collectively as the Toronto School.

    The university was the birthplace of insulin and stem cell research, and was the site of the first electron microscope in North America; the identification of the first black hole Cygnus X-1; multi-touch technology, and the development of the theory of NP-completeness.

    The university was one of several universities involved in early research of deep learning. It receives the most annual scientific research funding of any Canadian university and is one of two members of the Association of American Universities (US) outside the United States, the other being McGill(CA).

    The Varsity Blues are the athletic teams that represent the university in intercollegiate league matches, with ties to gridiron football, rowing and ice hockey. The earliest recorded instance of gridiron football occurred at University of Toronto’s University College in November 1861.

    The university’s Hart House is an early example of the North American student centre, simultaneously serving cultural, intellectual, and recreational interests within its large Gothic-revival complex.

    The University of Toronto has educated three Governors General of Canada, four Prime Ministers of Canada, three foreign leaders, and fourteen Justices of the Supreme Court. As of March 2019, ten Nobel laureates, five Turing Award winners, 94 Rhodes Scholars, and one Fields Medalist have been affiliated with the university.

    Early history

    The founding of a colonial college had long been the desire of John Graves Simcoe, the first Lieutenant-Governor of Upper Canada and founder of York, the colonial capital. As an University of Oxford (UK)-educated military commander who had fought in the American Revolutionary War, Simcoe believed a college was needed to counter the spread of republicanism from the United States. The Upper Canada Executive Committee recommended in 1798 that a college be established in York.

    On March 15, 1827, a royal charter was formally issued by King George IV, proclaiming “from this time one College, with the style and privileges of a University … for the education of youth in the principles of the Christian Religion, and for their instruction in the various branches of Science and Literature … to continue for ever, to be called King’s College.” The granting of the charter was largely the result of intense lobbying by John Strachan, the influential Anglican Bishop of Toronto who took office as the college’s first president. The original three-storey Greek Revival school building was built on the present site of Queen’s Park.

    Under Strachan’s stewardship, King’s College was a religious institution closely aligned with the Church of England and the British colonial elite, known as the Family Compact. Reformist politicians opposed the clergy’s control over colonial institutions and fought to have the college secularized. In 1849, after a lengthy and heated debate, the newly elected responsible government of the Province of Canada voted to rename King’s College as the University of Toronto and severed the school’s ties with the church. Having anticipated this decision, the enraged Strachan had resigned a year earlier to open Trinity College as a private Anglican seminary. University College was created as the nondenominational teaching branch of the University of Toronto. During the American Civil War the threat of Union blockade on British North America prompted the creation of the University Rifle Corps which saw battle in resisting the Fenian raids on the Niagara border in 1866. The Corps was part of the Reserve Militia lead by Professor Henry Croft.

    Established in 1878, the School of Practical Science was the precursor to the Faculty of Applied Science and Engineering which has been nicknamed Skule since its earliest days. While the Faculty of Medicine opened in 1843 medical teaching was conducted by proprietary schools from 1853 until 1887 when the faculty absorbed the Toronto School of Medicine. Meanwhile the university continued to set examinations and confer medical degrees. The university opened the Faculty of Law in 1887, followed by the Faculty of Dentistry in 1888 when the Royal College of Dental Surgeons became an affiliate. Women were first admitted to the university in 1884.

    A devastating fire in 1890 gutted the interior of University College and destroyed 33,000 volumes from the library but the university restored the building and replenished its library within two years. Over the next two decades a collegiate system took shape as the university arranged federation with several ecclesiastical colleges including Strachan’s Trinity College in 1904. The university operated the Royal Conservatory of Music from 1896 to 1991 and the Royal Ontario Museum from 1912 to 1968; both still retain close ties with the university as independent institutions. The University of Toronto Press was founded in 1901 as Canada’s first academic publishing house. The Faculty of Forestry founded in 1907 with Bernhard Fernow as dean was Canada’s first university faculty devoted to forest science. In 1910, the Faculty of Education opened its laboratory school, the University of Toronto Schools.

    World wars and post-war years

    The First and Second World Wars curtailed some university activities as undergraduate and graduate men eagerly enlisted. Intercollegiate athletic competitions and the Hart House Debates were suspended although exhibition and interfaculty games were still held. The David Dunlap Observatory in Richmond Hill opened in 1935 followed by the University of Toronto Institute for Aerospace Studies in 1949. The university opened satellite campuses in Scarborough in 1964 and in Mississauga in 1967. The university’s former affiliated schools at the Ontario Agricultural College and Glendon Hall became fully independent of the University of Toronto and became part of University of Guelph (CA) in 1964 and York University (CA) in 1965 respectively. Beginning in the 1980s reductions in government funding prompted more rigorous fundraising efforts.

    Since 2000

    In 2000 Kin-Yip Chun was reinstated as a professor of the university after he launched an unsuccessful lawsuit against the university alleging racial discrimination. In 2017 a human rights application was filed against the University by one of its students for allegedly delaying the investigation of sexual assault and being dismissive of their concerns. In 2018 the university cleared one of its professors of allegations of discrimination and antisemitism in an internal investigation after a complaint was filed by one of its students.

    The University of Toronto was the first Canadian university to amass a financial endowment greater than c. $1 billion in 2007. On September 24, 2020 the university announced a $250 million gift to the Faculty of Medicine from businessman and philanthropist James C. Temerty- the largest single philanthropic donation in Canadian history. This broke the previous record for the school set in 2019 when Gerry Schwartz and Heather Reisman jointly donated $100 million for the creation of a 750,000-square foot innovation and artificial intelligence centre.

    Research

    Since 1926 the University of Toronto has been a member of the Association of American Universities (US) a consortium of the leading North American research universities. The university manages by far the largest annual research budget of any university in Canada with sponsored direct-cost expenditures of $878 million in 2010. In 2018 the University of Toronto was named the top research university in Canada by Research Infosource with a sponsored research income (external sources of funding) of $1,147.584 million in 2017. In the same year the university’s faculty averaged a sponsored research income of $428,200 while graduate students averaged a sponsored research income of $63,700. The federal government was the largest source of funding with grants from the Canadian Institutes of Health Research; the Natural Sciences and Engineering Research Council; and the Social Sciences and Humanities Research Council amounting to about one-third of the research budget. About eight percent of research funding came from corporations- mostly in the healthcare industry.

    The first practical electron microscope was built by the physics department in 1938. During World War II the university developed the G-suit- a life-saving garment worn by Allied fighter plane pilots later adopted for use by astronauts.Development of the infrared chemiluminescence technique improved analyses of energy behaviours in chemical reactions. In 1963 the asteroid 2104 Toronto was discovered in the David Dunlap Observatory (CA) in Richmond Hill and is named after the university. In 1972 studies on Cygnus X-1 led to the publication of the first observational evidence proving the existence of black holes. Toronto astronomers have also discovered the Uranian moons of Caliban and Sycorax; the dwarf galaxies of Andromeda I, II and III; and the supernova SN 1987A. A pioneer in computing technology the university designed and built UTEC- one of the world’s first operational computers- and later purchased Ferut- the second commercial computer after UNIVAC I. Multi-touch technology was developed at Toronto with applications ranging from handheld devices to collaboration walls. The AeroVelo Atlas which won the Igor I. Sikorsky Human Powered Helicopter Competition in 2013 was developed by the university’s team of students and graduates and was tested in Vaughan.

    The discovery of insulin at the University of Toronto in 1921 is considered among the most significant events in the history of medicine. The stem cell was discovered at the university in 1963 forming the basis for bone marrow transplantation and all subsequent research on adult and embryonic stem cells. This was the first of many findings at Toronto relating to stem cells including the identification of pancreatic and retinal stem cells. The cancer stem cell was first identified in 1997 by Toronto researchers who have since found stem cell associations in leukemia; brain tumors; and colorectal cancer. Medical inventions developed at Toronto include the glycaemic index; the infant cereal Pablum; the use of protective hypothermia in open heart surgery; and the first artificial cardiac pacemaker. The first successful single-lung transplant was performed at Toronto in 1981 followed by the first nerve transplant in 1988; and the first double-lung transplant in 1989. Researchers identified the maturation promoting factor that regulates cell division and discovered the T-cell receptor which triggers responses of the immune system. The university is credited with isolating the genes that cause Fanconi anemia; cystic fibrosis; and early-onset Alzheimer’s disease among numerous other diseases. Between 1914 and 1972 the university operated the Connaught Medical Research Laboratories- now part of the pharmaceutical corporation Sanofi-Aventis. Among the research conducted at the laboratory was the development of gel electrophoresis.

    The University of Toronto is the primary research presence that supports one of the world’s largest concentrations of biotechnology firms. More than 5,000 principal investigators reside within 2 kilometres (1.2 mi) from the university grounds in Toronto’s Discovery District conducting $1 billion of medical research annually. MaRS Discovery District is a research park that serves commercial enterprises and the university’s technology transfer ventures. In 2008, the university disclosed 159 inventions and had 114 active start-up companies. Its SciNet Consortium operates the most powerful supercomputer in Canada.

     
  • richardmitnick 12:49 pm on June 9, 2021 Permalink | Reply
    Tags: "CHIME telescope detects more than 500 mysterious fast radio bursts in its first year of operation", , , , FRB's fall in two distinct classes: those that repeat and those that don’t., FRB's Fast radio Bursts, FRBs blaze for a few milliseconds before vanishing without a trace., , MIT’s Kavli Institute for Astrophysics and Space Research (US), Observations strongly suggest that repeaters and one-offs arise from separate mechanisms and astrophysical sources., , Since the first FRB was discovered in 2007 radio astronomers have only caught sight of around 140 bursts in their scopes., To catch sight of a fast radio burst is to be extremely lucky in where and when you point your radio dish.   

    From Massachusetts Institute of Technology (US): Women in STEM-Kaitlyn Shin “CHIME telescope detects more than 500 mysterious fast radio bursts in its first year of operation” 

    MIT News

    From Massachusetts Institute of Technology (US)

    June 9, 2021
    Jennifer Chu | MIT News Office

    The large radio telescope CHIME, pictured here, has detected more than 500 mysterious fast radio bursts in its first year of operation, MIT researchers report.
    Credits: Image: Courtesy of CHIME.

    To catch sight of a fast radio burst is to be extremely lucky in where and when you point your radio dish. Fast radio bursts, or FRBs, are oddly bright flashes of light, registering in the radio band of the electromagnetic spectrum, that blaze for a few milliseconds before vanishing without a trace.

    These brief and mysterious beacons have been spotted in various and distant parts of the universe, as well as in our own galaxy. Their origins are unknown, and their appearance is unpredictable. Since the first was discovered in 2007 radio astronomers have only caught sight of around 140 bursts in their scopes.

    Now, a large stationary radio telescope in British Columbia has nearly quadrupled the number of fast radio bursts discovered to date. The telescope, known as CHIME, for the Canadian Hydrogen Intensity Mapping Experiment, has detected 535 new fast radio bursts during its first year of operation, between 2018 and 2019.

    Scientists with the CHIME Collaboration, including researchers at MIT, have assembled the new signals in the telescope’s first FRB catalog, which they will present this week at the American Astronomical Society (US) Meeting.

    The new catalog significantly expands the current library of known FRBs, and is already yielding clues as to their properties. For instance, the newly discovered bursts appear to fall in two distinct classes: those that repeat and those that don’t. Scientists identified 18 FRB sources that burst repeatedly, while the rest appear to be one-offs. The repeaters also look different, with each burst lasting slightly longer and emitting more focused radio frequencies than bursts from single, nonrepeating FRBs.

    These observations strongly suggest that repeaters and one-offs arise from separate mechanisms and astrophysical sources. With more observations, astronomers hope soon to pin down the extreme origins of these curiously bright signals.

    “Before CHIME, there were less than 100 total discovered FRBs; now, after one year of observation, we’ve discovered hundreds more,” says CHIME member Kaitlyn Shin, a graduate student in MIT’s Department of Physics. “With all these sources, we can really start getting a picture of what FRBs look like as a whole, what astrophysics might be driving these events, and how they can be used to study the universe going forward.”

    Seeing flashes

    CHIME comprises four massive cylindrical radio antennas, roughly the size and shape of snowboarding half-pipes, located at the Dominion Radio Astrophysical Observatory, operated by the National Research Council of Canada in British Columbia, Canada. CHIME is a stationary array, with no moving parts. The telescope receives radio signals each day from half of the sky as the Earth rotates.

    While most radio astronomy is done by swiveling a large dish to focus light from different parts of the sky, CHIME stares, motionless, at the sky, and focuses incoming signals using a correlator — a powerful digital signaling processor that can work through huge amounts of data, at a rate of about 7 terabits per second, equivalent to a few percent of the world’s internet traffic.

    “Digital signal processing is what makes CHIME able to reconstruct and ‘look’ in thousands of directions simultaneously,” says Kiyoshi Masui, assistant professor of physics at MIT, who will lead the group’s conference presentation. “That’s what helps us detect FRBs a thousand times more often than a traditional telescope.”

    Over the first year of operation, CHIME detected 535 new fast radio bursts. When the scientists mapped their locations, they found the bursts were evenly distributed in space, seeming to arise from any and all parts of the sky. From the FRBs that CHIME was able to detect, the scientists calculated that bright fast radio bursts occur at a rate of about 800 per day across the entire sky — the most precise estimate of FRBs overall rate to date.

    “That’s kind of the beautiful thing about this field — FRBs are really hard to see, but they’re not uncommon,” says Masui, who is a member of MIT’s Kavli Institute for Astrophysics and Space Research (US). “If your eyes could see radio flashes the way you can see camera flashes, you would see them all the time if you just looked up.”

    Mapping the universe

    As radio waves travel across space, any interstellar gas, or plasma, along the way can distort or disperse the wave’s properties and trajectory. The degree to which a radio wave is dispersed can give clues to how much gas it passed through, and possibly how much distance it has traveled from its source.

    For each of the 535 FRBs that CHIME detected, Masui and his colleagues measured its dispersion, and found that most bursts likely originated from far-off sources within distant galaxies. The fact that the bursts were bright enough to be detected by CHIME suggests that they must have been produced by extremely energetic sources. As the telescope detects more FRBs, scientists hope to pin down exactly what kind of exotic phenomena could generate such ultrabright, ultrafast signals.

    Scientists also plan to use the bursts, and their dispersion estimates, to map the distribution of gas throughout the universe.

    “Each FRB gives us some information of how far they’ve propagated and how much gas they’ve propagated through,” Shin says. “With large numbers of FRBs, we can hopefully figure out how gas and matter are distributed on very large scales in the universe. So, alongside the mystery of what FRBs are themselves, there’s also the exciting potential for FRBs as powerful cosmological probes in the future.”

    This research was supported by various institutions including the Canada Foundation for Innovation, the Dunlap Institute for Astronomy and Astrophysics at the University of Toronto, the Canadian Institute for Advanced Research, McGill University and the McGill Space Institute via the Trottier Family Foundation, and the University of British Columbia.

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    MIT Seal

    USPS “Forever” postage stamps celebrating Innovation at MIT.

    MIT Campus

    Massachusetts Institute of Technology (MIT)(US) is a private land-grant research university in Cambridge, Massachusetts. The institute has an urban campus that extends more than a mile (1.6 km) alongside the Charles River. The institute also encompasses a number of major off-campus facilities such as the MIT Lincoln Laboratory, the Bates Center, and the Haystack Observatory, as well as affiliated laboratories such as the Broad and Whitehead Institutes.

    Founded in 1861 in response to the increasing industrialization of the United States, MIT adopted a European polytechnic university model and stressed laboratory instruction in applied science and engineering. It has since played a key role in the development of many aspects of modern science, engineering, mathematics, and technology, and is widely known for its innovation and academic strength. It is frequently regarded as one of the most prestigious universities in the world.

    As of December 2020, 97 Nobel laureates, 26 Turing Award winners, and 8 Fields Medalists have been affiliated with MIT as alumni, faculty members, or researchers. In addition, 58 National Medal of Science recipients, 29 National Medals of Technology and Innovation recipients, 50 MacArthur Fellows, 80 Marshall Scholars, 3 Mitchell Scholars, 22 Schwarzman Scholars, 41 astronauts, and 16 Chief Scientists of the U.S. Air Force have been affiliated with MIT. The university also has a strong entrepreneurial culture and MIT alumni have founded or co-founded many notable companies. MIT is a member of the Association of American Universities (AAU).

    Foundation and vision

    In 1859, a proposal was submitted to the Massachusetts General Court to use newly filled lands in Back Bay, Boston for a “Conservatory of Art and Science”, but the proposal failed. A charter for the incorporation of the Massachusetts Institute of Technology, proposed by William Barton Rogers, was signed by John Albion Andrew, the governor of Massachusetts, on April 10, 1861.

    Rogers, a professor from the University of Virginia (US), wanted to establish an institution to address rapid scientific and technological advances. He did not wish to found a professional school, but a combination with elements of both professional and liberal education, proposing that:

    “The true and only practicable object of a polytechnic school is, as I conceive, the teaching, not of the minute details and manipulations of the arts, which can be done only in the workshop, but the inculcation of those scientific principles which form the basis and explanation of them, and along with this, a full and methodical review of all their leading processes and operations in connection with physical laws.”

    The Rogers Plan reflected the German research university model, emphasizing an independent faculty engaged in research, as well as instruction oriented around seminars and laboratories.

    Early developments

    Two days after MIT was chartered, the first battle of the Civil War broke out. After a long delay through the war years, MIT’s first classes were held in the Mercantile Building in Boston in 1865. The new institute was founded as part of the Morrill Land-Grant Colleges Act to fund institutions “to promote the liberal and practical education of the industrial classes” and was a land-grant school. In 1863 under the same act, the Commonwealth of Massachusetts founded the Massachusetts Agricultural College, which developed as the University of Massachusetts Amherst (US)). In 1866, the proceeds from land sales went toward new buildings in the Back Bay.

    MIT was informally called “Boston Tech”. The institute adopted the European polytechnic university model and emphasized laboratory instruction from an early date. Despite chronic financial problems, the institute saw growth in the last two decades of the 19th century under President Francis Amasa Walker. Programs in electrical, chemical, marine, and sanitary engineering were introduced, new buildings were built, and the size of the student body increased to more than one thousand.

    The curriculum drifted to a vocational emphasis, with less focus on theoretical science. The fledgling school still suffered from chronic financial shortages which diverted the attention of the MIT leadership. During these “Boston Tech” years, MIT faculty and alumni rebuffed Harvard University (US) president (and former MIT faculty) Charles W. Eliot’s repeated attempts to merge MIT with Harvard College’s Lawrence Scientific School. There would be at least six attempts to absorb MIT into Harvard. In its cramped Back Bay location, MIT could not afford to expand its overcrowded facilities, driving a desperate search for a new campus and funding. Eventually, the MIT Corporation approved a formal agreement to merge with Harvard, over the vehement objections of MIT faculty, students, and alumni. However, a 1917 decision by the Massachusetts Supreme Judicial Court effectively put an end to the merger scheme.

    In 1916, the MIT administration and the MIT charter crossed the Charles River on the ceremonial barge Bucentaur built for the occasion, to signify MIT’s move to a spacious new campus largely consisting of filled land on a one-mile-long (1.6 km) tract along the Cambridge side of the Charles River. The neoclassical “New Technology” campus was designed by William W. Bosworth and had been funded largely by anonymous donations from a mysterious “Mr. Smith”, starting in 1912. In January 1920, the donor was revealed to be the industrialist George Eastman of Rochester, New York, who had invented methods of film production and processing, and founded Eastman Kodak. Between 1912 and 1920, Eastman donated $20 million ($236.6 million in 2015 dollars) in cash and Kodak stock to MIT.

    Curricular reforms

    In the 1930s, President Karl Taylor Compton and Vice-President (effectively Provost) Vannevar Bush emphasized the importance of pure sciences like physics and chemistry and reduced the vocational practice required in shops and drafting studios. The Compton reforms “renewed confidence in the ability of the Institute to develop leadership in science as well as in engineering”. Unlike Ivy League schools, MIT catered more to middle-class families, and depended more on tuition than on endowments or grants for its funding. The school was elected to the Association of American Universities (US)in 1934.

    Still, as late as 1949, the Lewis Committee lamented in its report on the state of education at MIT that “the Institute is widely conceived as basically a vocational school”, a “partly unjustified” perception the committee sought to change. The report comprehensively reviewed the undergraduate curriculum, recommended offering a broader education, and warned against letting engineering and government-sponsored research detract from the sciences and humanities. The School of Humanities, Arts, and Social Sciences and the MIT Sloan School of Management were formed in 1950 to compete with the powerful Schools of Science and Engineering. Previously marginalized faculties in the areas of economics, management, political science, and linguistics emerged into cohesive and assertive departments by attracting respected professors and launching competitive graduate programs. The School of Humanities, Arts, and Social Sciences continued to develop under the successive terms of the more humanistically oriented presidents Howard W. Johnson and Jerome Wiesner between 1966 and 1980.

    MIT’s involvement in military science surged during World War II. In 1941, Vannevar Bush was appointed head of the federal Office of Scientific Research and Development and directed funding to only a select group of universities, including MIT. Engineers and scientists from across the country gathered at MIT’s Radiation Laboratory, established in 1940 to assist the British military in developing microwave radar. The work done there significantly affected both the war and subsequent research in the area. Other defense projects included gyroscope-based and other complex control systems for gunsight, bombsight, and inertial navigation under Charles Stark Draper’s Instrumentation Laboratory; the development of a digital computer for flight simulations under Project Whirlwind; and high-speed and high-altitude photography under Harold Edgerton. By the end of the war, MIT became the nation’s largest wartime R&D contractor (attracting some criticism of Bush), employing nearly 4000 in the Radiation Laboratory alone and receiving in excess of $100 million ($1.2 billion in 2015 dollars) before 1946. Work on defense projects continued even after then. Post-war government-sponsored research at MIT included SAGE and guidance systems for ballistic missiles and Project Apollo.

    These activities affected MIT profoundly. A 1949 report noted the lack of “any great slackening in the pace of life at the Institute” to match the return to peacetime, remembering the “academic tranquility of the prewar years”, though acknowledging the significant contributions of military research to the increased emphasis on graduate education and rapid growth of personnel and facilities. The faculty doubled and the graduate student body quintupled during the terms of Karl Taylor Compton, president of MIT between 1930 and 1948; James Rhyne Killian, president from 1948 to 1957; and Julius Adams Stratton, chancellor from 1952 to 1957, whose institution-building strategies shaped the expanding university. By the 1950s, MIT no longer simply benefited the industries with which it had worked for three decades, and it had developed closer working relationships with new patrons, philanthropic foundations and the federal government.

    In late 1960s and early 1970s, student and faculty activists protested against the Vietnam War and MIT’s defense research. In this period MIT’s various departments were researching helicopters, smart bombs and counterinsurgency techniques for the war in Vietnam as well as guidance systems for nuclear missiles. The Union of Concerned Scientists was founded on March 4, 1969 during a meeting of faculty members and students seeking to shift the emphasis on military research toward environmental and social problems. MIT ultimately divested itself from the Instrumentation Laboratory and moved all classified research off-campus to the MIT (US) Lincoln Laboratoryfacility in 1973 in response to the protests. The student body, faculty, and administration remained comparatively unpolarized during what was a tumultuous time for many other universities. Johnson was seen to be highly successful in leading his institution to “greater strength and unity” after these times of turmoil. However six MIT students were sentenced to prison terms at this time and some former student leaders, such as Michael Albert and George Katsiaficas, are still indignant about MIT’s role in military research and its suppression of these protests. (Richard Leacock’s film, November Actions, records some of these tumultuous events.)

    In the 1980s, there was more controversy at MIT over its involvement in SDI (space weaponry) and CBW (chemical and biological warfare) research. More recently, MIT’s research for the military has included work on robots, drones and ‘battle suits’.

    Recent history

    MIT has kept pace with and helped to advance the digital age. In addition to developing the predecessors to modern computing and networking technologies, students, staff, and faculty members at Project MAC, the Artificial Intelligence Laboratory, and the Tech Model Railroad Club wrote some of the earliest interactive computer video games like Spacewar! and created much of modern hacker slang and culture. Several major computer-related organizations have originated at MIT since the 1980s: Richard Stallman’s GNU Project and the subsequent Free Software Foundation were founded in the mid-1980s at the AI Lab; the MIT Media Lab was founded in 1985 by Nicholas Negroponte and Jerome Wiesner to promote research into novel uses of computer technology; the World Wide Web Consortium standards organization was founded at the Laboratory for Computer Science in 1994 by Tim Berners-Lee; the MIT OpenCourseWare project has made course materials for over 2,000 MIT classes available online free of charge since 2002; and the One Laptop per Child initiative to expand computer education and connectivity to children worldwide was launched in 2005.

    MIT was named a sea-grant college in 1976 to support its programs in oceanography and marine sciences and was named a space-grant college in 1989 to support its aeronautics and astronautics programs. Despite diminishing government financial support over the past quarter century, MIT launched several successful development campaigns to significantly expand the campus: new dormitories and athletics buildings on west campus; the Tang Center for Management Education; several buildings in the northeast corner of campus supporting research into biology, brain and cognitive sciences, genomics, biotechnology, and cancer research; and a number of new “backlot” buildings on Vassar Street including the Stata Center. Construction on campus in the 2000s included expansions of the Media Lab, the Sloan School’s eastern campus, and graduate residences in the northwest. In 2006, President Hockfield launched the MIT Energy Research Council to investigate the interdisciplinary challenges posed by increasing global energy consumption.

    In 2001, inspired by the open source and open access movements, MIT launched OpenCourseWare to make the lecture notes, problem sets, syllabi, exams, and lectures from the great majority of its courses available online for no charge, though without any formal accreditation for coursework completed. While the cost of supporting and hosting the project is high, OCW expanded in 2005 to include other universities as a part of the OpenCourseWare Consortium, which currently includes more than 250 academic institutions with content available in at least six languages. In 2011, MIT announced it would offer formal certification (but not credits or degrees) to online participants completing coursework in its “MITx” program, for a modest fee. The “edX” online platform supporting MITx was initially developed in partnership with Harvard and its analogous “Harvardx” initiative. The courseware platform is open source, and other universities have already joined and added their own course content. In March 2009 the MIT faculty adopted an open-access policy to make its scholarship publicly accessible online.

    MIT has its own police force. Three days after the Boston Marathon bombing of April 2013, MIT Police patrol officer Sean Collier was fatally shot by the suspects Dzhokhar and Tamerlan Tsarnaev, setting off a violent manhunt that shut down the campus and much of the Boston metropolitan area for a day. One week later, Collier’s memorial service was attended by more than 10,000 people, in a ceremony hosted by the MIT community with thousands of police officers from the New England region and Canada. On November 25, 2013, MIT announced the creation of the Collier Medal, to be awarded annually to “an individual or group that embodies the character and qualities that Officer Collier exhibited as a member of the MIT community and in all aspects of his life”. The announcement further stated that “Future recipients of the award will include those whose contributions exceed the boundaries of their profession, those who have contributed to building bridges across the community, and those who consistently and selflessly perform acts of kindness”.

    In September 2017, the school announced the creation of an artificial intelligence research lab called the MIT-IBM Watson AI Lab. IBM will spend $240 million over the next decade, and the lab will be staffed by MIT and IBM scientists. In October 2018 MIT announced that it would open a new Schwarzman College of Computing dedicated to the study of artificial intelligence, named after lead donor and The Blackstone Group CEO Stephen Schwarzman. The focus of the new college is to study not just AI, but interdisciplinary AI education, and how AI can be used in fields as diverse as history and biology. The cost of buildings and new faculty for the new college is expected to be $1 billion upon completion.

    The Caltech/MIT Advanced aLIGO (US) was designed and constructed by a team of scientists from California Institute of Technology, MIT, and industrial contractors, and funded by the National Science Foundation (US) .

    MIT/Caltech Advanced aLigo .

    It was designed to open the field of gravitational-wave astronomy through the detection of gravitational waves predicted by general relativity. Gravitational waves were detected for the first time by the LIGO detector in 2015. For contributions to the LIGO detector and the observation of gravitational waves, two Caltech physicists, Kip Thorne and Barry Barish, and MIT physicist Rainer Weiss won the Nobel Prize in physics in 2017. Weiss, who is also an MIT graduate, designed the laser interferometric technique, which served as the essential blueprint for the LIGO.

    The mission of MIT is to advance knowledge and educate students in science, technology, and other areas of scholarship that will best serve the nation and the world in the twenty-first century. We seek to develop in each member of the MIT community the ability and passion to work wisely, creatively, and effectively for the betterment of humankind.

     
  • richardmitnick 11:03 am on November 17, 2020 Permalink | Reply
    Tags: "ASKAP Finds a Real-Time Radio Burst, , , , , but No Glow", , FRB 191001, FRB's Fast radio Bursts   

    From AAS NOVA: “ASKAP Finds a Real-Time Radio Burst, but No Glow” 

    AASNOVA

    From AAS NOVA

    16 November 2020
    Susanna Kohler

    Australian Square Kilometre Array Pathfinder (ASKAP) is a radio telescope array located at Murchison Radio-astronomy Observatory (MRO) in the Australian Mid West. ASKAP consists of 36 identical parabolic antennas, each 12 metres in diameter, working together as a single instrument with a total collecting area of approximately 4,000 square metres.

    As powerful millisecond bursts of radio emission continue to light up our detectors from across the universe, the hunt for the origins of these fast radio bursts continues. It’s the search for light before and after the burst, however, that might prove key to unraveling their mystery.

    2
    Artist’s impression of the ASKAP radio telescope finding a fast radio burst. Other observatories are shown joining in follow-up observations. Credit:CSIRO/Andrew Howells.

    An Extragalactic Puzzle

    Since the first discovery of fast radio bursts (FRBs) more than a decade ago, we’ve found ~100 of them, including more than 20 that have been observed to repeat. Despite this growing sample — and though we’ve now localized repeating and non-repeating FRBs to distant host galaxies — we still don’t know with certainty what causes them.

    Many of the leading origin theories for FRBs come with predictions of other emission that should complement the radio flash. The birth of a magnetized neutron star, for instance, should produce not only an FRB, but also a radio afterglow — steadier radio emission that appears after the burst and then slowly fades over time.

    The fact that we haven’t yet found any radio afterglows definitively associated with FRBs means one of three things: 1) they don’t happen, 2) they’re fainter than we can detect, or 3) they evolve on quicker timescales than we’ve been surveying, so they’ve already faded by the time we look. A new radio array enterprise is focusing on ruling out the third of these possibilities.

    Real-Time Eyes on the Skies

    To catch a quickly evolving afterglow, we need real-time observations of FRBs — allowing us to monitor the source for radio emission before, during, and immediately after the burst. To this end, a new survey was begun in mid-2019 with the The Australian Square Kilometre Array Pathfinder (ASKAP): the Commensal Real-time ASKAP Fast Transients Survey (CRAFT).

    CRAFT runs continuous low-time-resolution observations of the sky while ASKAP is being used for other survey science projects. When an FRB is spotted, the survey automatically saves the data from before and after the FRB itself, so that the survey team can search it for radio precursor and afterglow emission.

    In a new study, a team of scientists led by Shivani Bhandari (Australia Telescope National Facility, CSIRO (AU) reports the first detection of an FRB in this mode: FRB 191001.

    The Verdict: No Glow

    From the CRAFT data, the authors were able to localize FRB 191001 to the outskirts of a star-forming spiral galaxy at a redshift of z = 0.234 (that’s nearly 3 billion light-years away!). The CRAFT data revealed neither a persistent, compact radio source before the burst, nor a slowly varying radio afterglow after the burst.

    What does this mean? The lack of detectable afterglow for FRB 191001 alone doesn’t yet rule out any formation scenarios — but it does demonstrate that the afterglow was either fainter than our detection thresholds, or it didn’t occur at all.

    And this CRAFT detection is just the start! With more observations like this one — especially of closer FRBs that would be expected to appear with correspondingly brighter afterglows — we may soon be able to narrow down the options of what causes these mysterious flashes.

    Citation

    “Limits on Precursor and Afterglow Radio Emission from a Fast Radio Burst in a Star-forming Galaxy,” Shivani Bhandari et al 2020 ApJL 901 L20.

    https://iopscience.iop.org/article/10.3847/2041-8213/abb462

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    1

    AAS Mission and Vision Statement

    The mission of the American Astronomical Society is to enhance and share humanity’s scientific understanding of the Universe.

    The Society, through its publications, disseminates and archives the results of astronomical research. The Society also communicates and explains our understanding of the universe to the public.
    The Society facilitates and strengthens the interactions among members through professional meetings and other means. The Society supports member divisions representing specialized research and astronomical interests.
    The Society represents the goals of its community of members to the nation and the world. The Society also works with other scientific and educational societies to promote the advancement of science.
    The Society, through its members, trains, mentors and supports the next generation of astronomers. The Society supports and promotes increased participation of historically underrepresented groups in astronomy.
    The Society assists its members to develop their skills in the fields of education and public outreach at all levels. The Society promotes broad interest in astronomy, which enhances science literacy and leads many to careers in science and engineering.

    Adopted June 7, 2009

     
  • richardmitnick 1:49 pm on November 16, 2020 Permalink | Reply
    Tags: "Cosmic flashes come in all different sizes", , , , , , FRB's Fast radio Bursts, , ,   

    From Chalmers tekniska högskola (SE): “Cosmic flashes come in all different sizes” 

    From Chalmers tekniska högskola (SE)

    Nov 16, 2020
    Robert Cumming, communicator
    Onsala Space Observatory, Chalmers
    +46 31-772 5500 or
    +46 70 493 3114,
    robert.cumming@chalmers.se.

    Franz Kirsten, astronomer,
    Onsala Space Observatory, Chalmers,
    +46 31-772 5532,
    franz.kirsten@chalmers.se

    Joshua Worth
    Press officer
    +46-31-772 6379
    joshua.worth@chalmers.se

    1

    By studying the site of a spectacular stellar explosion seen in April 2020, a Chalmers-led team of scientists have used four European radio telescopes to confirm that astronomy’s most exciting puzzle is about to be solved. Fast radio bursts, unpredictable millisecond-long radio signals seen at huge distances across the universe, are generated by extreme stars called magnetars – and are astonishingly diverse in brightness.

    For over a decade, the phenomenon known as FRB’s -fast radio bursts has excited and mystified astronomers. These extraordinarily bright but extremely brief flashes of radio waves – lasting only milliseconds – reach Earth from galaxies billions of light years away.

    In April 2020, one of the bursts was for the first time detected from within our galaxy, the Milky Way, by radio telescopes CHIME and STARE2.

    CHIME Canadian Hydrogen Intensity Mapping Experiment -A partnership between the University of British Columbia (CA), the University of Toronto (CA), McGill University (CA), Yale and the National Research Council in British Columbia (CA), at the Dominion Radio Astrophysical Observatory in Penticton, British Columbia, (CA) Altitude 545 m (1,788 ft).

    Caltech STARE2 Radio telescope at Owens Valley Radio Observatory, located near Big Pine, California (US) in Owens Valley. It lies east of the Sierra Nevada, approximately 350 kilometers (220 mi) north of Los Angeles and 20 kilometers (12 mi) southeast of Bishop. It was established in 1956, and is owned and operated by the California Institute of Technology (Caltech), Altitude 1,222 m (4,009 ft).

    The unexpected flare was traced to a previously-known source only 25 000 light years from Earth in the constellation of Vulpecula, the Fox, and scientists all over the world coordinated their efforts to follow up the discovery.

    In May, a team of scientists led by Franz Kirsten, from Chalmers University of Technology, pointed four of Europe’s best radio telescopes towards the source, known as SGR 1935+2154. Their results are published today in a paper in the journal Nature Astronomy, by Franz Kirsten (Onsala Space Observatory, Chalmers (SE)), M. P. Snelders, M. Jenkins (Anton Pannekoek Institute for Astronomy, University of Amsterdam) (NL) K. Nimmo (Anton Pannekoek Institute for Astronomy, University of Amsterdam (NL), and ASTRON, Netherlands Institute for Radio Astronomy (NL)), J. van den Eijnden (Anton Pannekoek Institute for Astronomy, University of Amsterdam and Department of Physics, Astrophysics, University of Oxford (UK)), J. W. T. Hessels (Anton Pannekoek Institute for Astronomy, University of Amsterdam, and ASTRON, Netherlands Institute for Radio Astronomy (NL)), M. P. Gawroński (Institute of Astronomy, Nicolaus Copernicus University, Toruń, (PL)) and Jun Yang (Onsala Space Observatory, Chalmers).

    “We didn’t know what to expect. Our radio telescopes had only rarely been able to see fast radio bursts, and this source seemed to be doing something completely new. We were hoping to be surprised!”, said Mark Snelders, team member from the Anton Pannekoek Institute for Astronomy, University of Amsterdam.

    The radio telescopes, one dish each in the Netherlands and Poland and two at Onsala Space Observatory in Sweden, monitored the source every night for more than four weeks after the discovery of the first flash, a total of 522 hours of observation.

    On the evening of May 24, the team got the surprise they were looking for. At 23:19 local time, the Westerbork telescope in the Netherlands, the only one of the group on duty, caught a dramatic and unexpected signal: two short bursts, each one millisecond long but 1.4 seconds apart.

    Kenzie Nimmo, astronomer at Anton Pannekoek Institute for Astronomy and ASTRON, is a member of the team.

    “We clearly saw two bursts, extremely close in time. Like the flash seen from the same source on April 28, this looked just like the fast radio bursts we’d been seeing from the distant universe, only dimmer. The two bursts we detected on May 24 were even fainter than that”, she said.

    This was new, strong evidence connecting fast radio bursts with magnetars, the scientists thought. Like more distant sources of fast radio bursts, SGR 1935+2154 seemed to be producing bursts at random intervals, and over a huge brightness range.

    “The brightest flashes from this magnetar are at least ten million times as bright as the faintest ones. We asked ourselves, could that also be true for fast radio burst sources outside our galaxy? If so, then the universe’s magnetars are creating beams of radio waves that could be criss-crossing the cosmos all the time – and many of these could be within the reach of modest-sized telescopes like ours”, said team member Jason Hessels (Anton Pannekoek Institute for Astronomy and ASTRON, Netherlands).

    Neutron stars are the tiny, extremely dense remnants left behind when a short-lived star of more than eight times the mass of the Sun explodes as a supernova. For 50 years, astronomers have studied pulsars, neutron stars which with clock-like regularity send out pulses of radio waves and other radiation. All pulsars are believed to have strong magnetic fields, but the magnetars are the strongest known magnets in the universe, each with a magnetic field hundreds of trillions of times stronger than the Sun’s.

    In the future, the team aims to keep the radio telescopes monitoring SGR 1935+2154 and other nearby magnetars, in the hope of pinning down how these extreme stars actually make their brief blasts of radiation.

    Scientists have presented many ideas for how fast radio bursts are generated. Franz Kirsten, astronomer at Onsala Space Observatory, Chalmers University of Technology, who led the project, expects the rapid pace in understanding the physics behind fast radio bursts to continue.

    “The fireworks from this amazing, nearby magnetar have given us exciting clues about how fast radio bursts might be generated. The bursts we detected on May 24 could indicate a dramatic disturbance in the star’s magnetosphere, close to its surface. Other possible explanations, like shock waves further out from the magnetar, seem less likely, but I’d be delighted to be proved wrong. Whatever the answers, we can expect new measurements and new surprises in the months and years to come”, he said.

    The observations were carried out using the 25-metre RT1 telescope at Westerbork, Netherlands, both the 25-metre and 20-metre telescopes at Onsala Space Observatory, and the 32-metre telescope in Toruń, Poland.

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    Chalmers tekniska högskola (SE) is a Swedish university located in Gothenburg that focuses on research and education in technology, natural science, architecture, maritime and other management areas

    The University was founded in 1829 following a donation by William Chalmers, a director of the Swedish East India Company. He donated part of his fortune for the establishment of an “industrial school”. Chalmers was run as a private institution until 1937, when the institute became a state-owned university. In 1994, the school was incorporated as an aktiebolag under the control of the Swedish Government, the faculty and the Student Union. Chalmers is one of only three universities in Sweden which are named after a person, the other two being Karolinska Institutet and Linnaeus University.

     
  • richardmitnick 12:44 pm on November 4, 2020 Permalink | Reply
    Tags: "Astronomers report first detection of ultrabright radio flashes in our own galaxy", , , , , CHIME Experimental telescope a partnership of UBC (CA); UToronto (CA); McGill (CA); Yale and the National Research Council in British Columbia (CA) at the DRAO Penticton British Columbia (CA) Altitude, , FRB's Fast radio Bursts, , The observed radio pulses were produced by a magnetar - a type of neutron star with a hugely powerful magnetic field.   

    From MIT: “Astronomers report first detection of ultrabright radio flashes in our own galaxy” 

    MIT News

    From MIT News

    November 4, 2020
    Jennifer Chu

    The fast radio bursts are likely generated by a magnetar, the most magnetic type of star in the universe.

    Iconic depiction of Magnetar in Westerlund 1 ESO/L. Calçada.

    1
    This artist’s impression of a magnetar in outburst, showing complex magnetic field structure and beamed emission, is here imagined as following a crust-cracking episode.
    Credit: McGill University Graphic Design Team.

    Fast radio bursts are extremely bright flashes of energy that last for a fraction of a second, during which they can blast out more than 100 million times more power than the sun.

    Since they were first detected in 2007, astronomers have observed traces of fast radio bursts, or FRBs, scattered across the universe, but their sources have been too far away to clearly make out. It has been a mystery, then, as to what astrophysical objects could possibly produce such brief though brilliant radio flares.

    Now astronomers at MIT, McGill University (CA), the University of British Columbia (CA), the University of Toronto (CA), the Perimeter Institute for Theoretical Physics (CA), and elsewhere report that they have observed fast radio bursts in our own galaxy, for the first time. The radio pulses are the closest FRBs detected to date, and their proximity has allowed the team to pinpoint their source.

    It appears that the observed radio pulses were produced by a magnetar — a type of neutron star with a hugely powerful magnetic field. Physicists have hypothesized that magnetars might produce FRBs. This is the first time scientists have direct observational proof that magnetars are indeed sources of fast radio bursts.

    “There’s this great mystery as to what would produce these great outbursts of energy, which until now we’ve seen coming from halfway across the universe,” says Kiyoshi Masui, assistant professor of physics at MIT, who led the team’s analysis of the FRB’s brightness. “This is the first time we’ve been able to tie one of these exotic fast radio bursts to a single astrophysical object.”

    The researchers have published their results today in the journal Nature. The authors are all members of the Canadian Hydrogen Intensity Mapping Experiment (CHIME) Collaboration, a team of over 50 scientists led by McGill University, the University of British Columbia, the University of Toronto, the Perimeter Institute for Theoretical Physics, and the National Research Council of Canada.

    CHIME Canadian Hydrogen Intensity Mapping Experiment -A partnership between the University of British Columbia (CA), the University of Toronto (CA), McGill University (CA), Yale and the National Research Council in British Columbia (CA), at the Dominion Radio Astrophysical Observatory in Penticton, British Columbia, (CA) Altitude 545 m (1,788 ft).

    Staccato bursts

    The astronomers picked up signals of an FRB using the CHIME radio telescope at the Dominion Radio Astrophysical Observatory in British Columbia (CA). CHIME is made up of four large reflectors, each as long as a football field and resembling skateboarding halfpipes, which focus incoming radio waves onto over a thousand antennas. Together, the antennas continuously monitor swaths of the sky for incoming radio waves — energy emitted within the radio band of the electromagnetic spectrum.

    Toward the end of April 2020, astronomers picked up some bursts of activity, in the X-ray band of the spectrum, from a magnetar in the Milky Way, toward the galaxy’s center and about 30,000 light years from Earth. The magnetar is among a handful of known magnetars in our galaxy, and until April, it was, as Masui describes, a “run-of-the-mill” magnetar. Astronomers labeled it SGR 1935+2154, for its coordinates in the sky.

    “There was some buzz in the astronomy community about this magnetar that had become active in the X-ray, and it had been mentioned within our collaboration that we should keep an eye out for something more from this magnetar,” Masui says.

    Sure enough, the team found that, shortly after the magnetar burst in the X-ray band, CHIME picked up two sharp staccato peaks in the radio band, within several milliseconds of each other, signaling a fast radio burst. The researchers were able to track the radio bursts to a point in the sky that was within a fraction of a degree of SGR 1935+2154 — the same magnetar that was blasting out X-rays around the same time.

    “If it was coming from any other object close to the magnetar, it would be a very big coincidence,” says Masui.

    Masui then led the effort to measure the brightness of the magnetar as it was generating the radio bursts — a tricky task, as the bursts were detected at CHIME’s periphery, where the telescope is less sensitive, and its instrumentation is trickier to interpret. So the team used calibration data from other astrophysical sources to estimate the magnetar’s brightness.

    In the end, they calculated that the magnetar, in the fraction of a second that the FRB flashed, was 3,000 times brighter than any other magnetar radio signal that has yet been observed.

    “Measuring its brightness was really what established this is not a normal pulse,” Masui says. “This is a fast radio burst happening in our own galaxy, that is thousands of times brighter than any other pulse we’ve ever seen.”

    “Eyes open”

    Now that it’s been shown that magnetars can produce fast radio bursts, the question remains: how? While proposals abound, scientists are unsure of exactly how FRBs are generated in the universe, and specifically, how magnetars might produce them.

    Most radio emissions in the universe are produced through a process known as synchrotron radiation, in which a gas of randomly moving high-energy electrons interacts with magnetic fields, in a way that emits energy at radio frequencies. Radio waves are often generated in this way by supermassive black holes, supernova remnants, and hot gas sitting in galaxies.

    But physicists suspect that magnetars may generate radio waves through an entirely different process, where electrons, instead of interacting randomly with a magnetic field, are doing so en masse. This “coherent” process would be similar to the way in which we generate radio waves on Earth, by directing electrons through a wire, in the same direction.

    “We think some sort of process like that, some coherent currents running through space, is causing this radio emission that we see,” Masui says. “The mechanics of how that happens astrophysically, in magnetars or pulsars, is not well-understood.”

    Since the team discovered the radio-bursting magnetar, other groups have trained different telescopes on the source, and have reported that the magnetar has emitted subsequent radio bursts, though not nearly as intense as the initial FRB.

    “It’s been doing interesting things, and we’re trying to piece together what it all means,” Masui says. “We’ve got our eyes open for other magnetars, but the big thing now is to study this one source and really drill down to see what it tells us about how FRBs are made.”

    This research was funded, in part by the Canada Foundation for Innovation, and other supporting institutions.

    See the full article here .
    See also the full article from U Toronto Dunlap Institute for Astronomy and Astrophysics (CA) here.

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  • richardmitnick 9:17 am on August 25, 2020 Permalink | Reply
    Tags: "Will Radio Bursts Reveal Hidden Baryons?", , , , , , , , FRB's Fast radio Bursts, ,   

    From AAS NOVA: “Will Radio Bursts Reveal Hidden Baryons?” 

    AASNOVA

    From AAS NOVA

    24 August 2020
    Susanna Kohler

    Australian Square Kilometre Array Pathfinder (ASKAP) is a radio telescope array located at Murchison Radio-astronomy Observatory (MRO) in the Australian Mid West. ASKAP consists of 36 identical parabolic antennas, each 12 metres in diameter, working together as a single instrument with a total collecting area of approximately 4,000 square metres.


    Transients like fast radio bursts, detected with telescopes like the ASKAP array may be the key to identifying how much matter is hiding in our galaxy’s diffuse halo.

    The Earth, your body, and the electronic device you’re reading this on are all made up of ordinary, baryonic matter. A new study has now used bursts of radio emission to probe whether the outskirts of our galaxy are hiding vast quantities of “missing” baryonic matter.

    Missing Matter

    2
    The relative amounts of the different constituents of the universe. Ordinary baryonic matter makes up less than 5%. [ESA/Planck.]

    We’ve long known that only about 5% of the content of the universe is ordinary baryonic matter; the remainder is dark matter and dark energy. But when scientists have searched for this baryonic matter in the nearby universe, they found a puzzle: galaxies’ gas, dust, and stars only accounted for a small fraction of their expected baryonic matter.

    Our own Milky Way is no exception — it also has a baryon fraction much lower than the overall baryon fraction in the universe. So where are its missing baryons? Were they expelled from our galaxy at some point in the past? Or did the Milky Way retain its baryons — but we haven’t detected them yet?

    An Elusive Halo

    If our galaxy’s baryons are still around, a likely hiding place is in the Milky Way’s outskirts, in the circumgalactic medium (CGM).

    3
    The Sombrero galaxy, M104, provides an example of a galaxy and its halo — the diffuse gas that extends above and below the galaxy’s disk. [ESA/C. Carreau.]

    When our galaxy formed, gas was dragged inward with the collapsing dark-matter halo, shock heating and forming a surrounding bubble of hot, diffuse plasma — the CGM. This surrounding galactic halo may well contain our galaxy’s missing baryons today, but it’s very difficult to probe; since the gas is diffuse, we can’t measure it directly from within the Milky Way.

    A new study led by Emma Platts (University of Cape Town, South Africa) has instead measured the galactic halo’s matter by observing how distant signals interact with the CGM as they travel to us.

    Clues from Transients

    Platts and collaborators use two types of radio transients to measure CGM distribution: pulsars, which are pulsating neutron stars that reside in our galaxy’s disk, and fast radio bursts, which are brief flashes of radio emission that originate far beyond our galaxy.

    4
    Pulsars, which typically lie in the galactic disk, emit radiation that sweeps over the Earth like a lighthouse, appearing as pulses. These pulses become dispersed as they travel through the galaxy to reach us. [Bill Saxton/NRAO/AUI/NSF]

    Dame Susan Jocelyn Bell Burnell, discovered pulsars with radio astronomy. Jocelyn Bell at the Mullard Radio Astronomy Observatory, Cambridge University, taken for the Daily Herald newspaper in 1968. Denied the Nobel.

    Light from these sources travels across space to us, interacting with matter distributed along the way. The interactions slow down longer wavelengths of light more than shorter, causing the signal to spread out. The dispersion measure — the quantification of this spread — therefore tells us how much matter the signal traveled through to get to us.

    Probing Our Surroundings

    By statistically analyzing the distribution of pulsar and fast radio burst dispersion measures, Platts and collaborators placed bounds on the Milky Way halo’s dispersion measure: its minimum is set by the farthest pulsars, which lie interior to the halo, and its maximum is set by the closest fast radio bursts, which lie far beyond our halo in neighboring galaxies.

    Milky Way Halo NASA/ESA STScI

    So are the Milky Way’s missing baryons hiding in the CGM? We can’t say for certain yet, but the results suggest no, if the baryons are distributed in the same way as the dark matter. The future should hold more certainty though! Our sample of fast radio bursts is rapidly growing, and the authors estimate that once we’ve cataloged several thousand, we’ll be able to bound the content of the Milky Way’s halo more definitively.

    5
    Schematic illustrating how transient radio signals travel to us. Pulsars (marked by sun symbols) lie in the galaxy, interior to the halo; their signals are dispersed only by the Milky Way’s interstellar matter. Fast radio bursts (marked by lightning symbol) lie in other galaxies; their signals are dispersed by the Milky Way’s interstellar matter, its halo, the intergalactic medium, the host galaxy’s halo, and the host itself. These two types of transients can therefore place upper and lower bounds on the matter in the Milky Way’s halo. [Platts et al. 2020]

    Citation

    “A Data-driven Technique Using Millisecond Transients to Measure the Milky Way Halo,” E. Platts et al 2020 ApJL 895 L49.

    https://iopscience.iop.org/article/10.3847/2041-8213/ab930a

    See the full article here .


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    1

    AAS Mission and Vision Statement

    The mission of the American Astronomical Society is to enhance and share humanity’s scientific understanding of the Universe.

    The Society, through its publications, disseminates and archives the results of astronomical research. The Society also communicates and explains our understanding of the universe to the public.
    The Society facilitates and strengthens the interactions among members through professional meetings and other means. The Society supports member divisions representing specialized research and astronomical interests.
    The Society represents the goals of its community of members to the nation and the world. The Society also works with other scientific and educational societies to promote the advancement of science.
    The Society, through its members, trains, mentors and supports the next generation of astronomers. The Society supports and promotes increased participation of historically underrepresented groups in astronomy.
    The Society assists its members to develop their skills in the fields of education and public outreach at all levels. The Society promotes broad interest in astronomy, which enhances science literacy and leads many to careers in science and engineering.

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  • richardmitnick 11:42 am on May 1, 2020 Permalink | Reply
    Tags: "Exclusive: We Might Have First-Ever Detection of a Fast Radio Burst in Our Own Galaxy", , , , , , FRB's Fast radio Bursts,   

    From Science Alert- “Exclusive: We Might Have First-Ever Detection of a Fast Radio Burst in Our Own Galaxy” 

    ScienceAlert

    From Science Alert

    1 MAY 2020
    MICHELLE STARR

    A Milky Way magnetar called SGR 1935+2154 may have just massively contributed to solving the mystery of powerful deep-space radio signals that have vexed astronomers for years.

    1
    ATel #13682: AGILE observations of the SGR 1935+2154 “burst forest”

    On 28 April 2020, the dead star – sitting just 30,000 light-years away – was recorded by radio observatories around the world, seemingly flaring with a single, millisecond-long burst of incredibly bright radio waves that would have been detectable from another galaxy.

    In addition, global and space X-ray observatories recorded a very bright X-ray counterpart.

    Work on this event is very preliminary, with astronomers madly scrambling to analyse the swathes of data. But many seem in agreement that it could finally point to the source of fast radio bursts (FRBs).

    “This sort of, in most people’s minds, settles the origin of FRBs as coming from magnetars,” astronomer Shrinivas Kulkarni of Caltech, and member of one of the teams, the STARE2 survey that also detected the radio signal, told ScienceAlert.

    Fast radio bursts are one of the most fascinating mysteries in the cosmos. They are extremely powerful radio signals from deep space, galaxies millions of light-years away, some discharging more energy than 500 million Suns. Yet they last less than the blink of an eye – mere milliseconds in duration – and most of them don’t repeat, making them very hard to predict, trace, and therefore understand.

    Potential explanations have ranged from supernovae to aliens (which, sorry, is extremely unlikely). But one possibility that has been picking up steam is that FRBs are produced by magnetars.

    These are a particularly odd type of neutron star, the extremely dense core remnants left over after a massive star goes supernova. But magnetars have much more powerful magnetic fields than ordinary neutron stars – around 1,000 times stronger. How they got that way is something we don’t understand well, but it has an interesting effect on the star itself.

    As gravitational force tries to keep the star together – an inward force – the magnetic field is so powerful, it distorts the star’s shape. This leads to an ongoing tension between the two forces, Kulkarni explained, which occasionally produces gargantuan starquakes and giant magnetar flares.

    On 27 April 2020, SGR 1935+2154 was detected and observed by multiple instruments undergoing a spurt of activity, including the Swift Burst Alert Telescope, the AGILE satellite and the NICER ISS payload. It initially looked relatively normal, consistent with behaviour observed in other magnetars.

    3
    NASA Neil Gehrels Swift Observatory

    Italian Space Agency AGILE Spacecraft

    NASA/NICER on the ISS

    But then, on April 28, the Canadian Hydrogen Intensity Mapping Experiment (CHIME) – a telescope designed to scan the skies for transient events – made an unprecedented detection, a signal so powerful the system couldn’t quite quantify it. The detection was reported on The Astronomer’s Telegram.

    CHIME Canadian Hydrogen Intensity Mapping Experiment -A partnership between the University of British Columbia, the University of Toronto, McGill University, Yale and the National Research Council in British Columbia, at the Dominion Radio Astrophysical Observatory in Penticton, British Columbia, CA Altitude 545 m (1,788 ft)

    But the STARE2 survey, a project started by Caltech graduate student Christopher Bochenek, is designed exactly for the detection of local FRBs. It consists of three dipole radio antennas located hundreds of kilometres apart, which firstly can rule out local signals produced by human activities, and can also allow for signal triangulation.

    It received the signal loud and clear, with a fluence of over a million jansky milliseconds. Typically, we receive extragalactic FRBs at a few tens of jansky milliseconds. Once corrected for distance, the SGR 1935+2154 would be on the low end of FRB power – but it fits the profile, Kulkarni said.

    “If the same signal came from a nearby galaxy, like one of the nearby typical FRB galaxies, it would look like an FRB to us,” he told ScienceAlert. “Something like this has never been seen before.”

    But we also saw something else we’ve never seen in an extragalactic FRB, and that’s the X-ray counterpart. These are quite common in magnetar outbursts, of course. In fact, it is far more normal for magnetars to emit X-ray and gamma radiation than radio waves.

    The X-ray counterpart to the SGR 1935+2154 burst was not particularly strong or unusual, said astrophysicist Sandro Mereghetti of the National Institute for Astrophysics in Italy, and research scientist with the ESA’s INTEGRAL satellite. But it could imply that there’s a lot more to FRBs than we can currently detect.

    ESA/Integral

    “This is a very intriguing result and supports the association between FRBs and magnetars,” Mereghetti told ScienceAlert.

    “The FRB identified up to now are extragalactic. They have never been detected at X/gamma rays. An X-ray burst with luminosity like that of SGR1935 would be undetectable for an extragalactic source.”

    But that radio signal was undeniable. And, according to Kulkarni, it’s absolutely possible for a magnetar to produce even larger outbursts. SGR 1935+2154’s burst did not require much energy, for a magnetar, and the star could easily handle a burst a thousand times stronger.

    It’s certainly giddying stuff. But it’s important to bear in mind that this is early days yet. Astronomers are still conducting follow-up observations of the star using some of the most powerful tools we have.

    And they have yet to analyse the spectrum of the burst, to determine if it bears any similarities to the spectra of extragalactic fast radio bursts. If it doesn’t, we may be back to square one.

    Of course, even if SGR 1935+2154 does turn out to confirm a magnetar origin for fast radio bursts, that won’t mean it’s the only origin. Some of the signals behave very differently, repeating unpredictably. One source was recently found to be repeating on a 16-day cycle.

    Whatever SGR 1935+2154 tells us, we are far from completely resolving the complicated enigma these incredible signals represent – but it’s an incredibly exciting step forward.

    See the full article here .


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  • richardmitnick 9:32 am on April 15, 2020 Permalink | Reply
    Tags: , , , , , , , FRB's Fast radio Bursts   

    From astrobites: “How It’s Made, Fast Radio Burst Edition” 

    Astrobites bloc

    From astrobites

    1
    Artist’s conception of the localization of a fast radio burst to its host galaxy. [Danielle Futselaar]

    Title: Spectropolarimetric analysis of FRB 181112 at microsecond resolution: Implications for Fast Radio Burst emission mechanism
    Authors: Hyerin Cho et al.
    First Author’s Institution: Gwangju Institute of Science and Technology, Korea
    Status: Published in ApJL

    Fast radio bursts (FRBs) are probably the fastest growing and most interesting field in radio astronomy right now. These extragalactic, incredibly energetic bursts last just a few milliseconds and come in two flavors, singular and repeating. Recently the number of known FRBs has exploded, as the ​Canadian Hydrogen Intensity Mapping Experiment (CHIME) radio telescope has discovered about 20 repeating FRBs (and also redetected the famous FRB 121102) and over 700 single bursts (hinted at here).

    CHIME Canadian Hydrogen Intensity Mapping Experiment -A partnership between the University of British Columbia, the University of Toronto, McGill University, Yale and the National Research Council in British Columbia, at the Dominion Radio Astrophysical Observatory in Penticton, British Columbia, CA Altitude 545 m (1,788 ft)

    However, despite the huge growth in the known FRB population, we still don’t know what the source(s) of these bursts is (are). Today’s paper looks at possible explanations for the properties of one FRB in particular to try to figure out what its source might be.

    Your Friendly Neighborhood FRB

    A number of previous astrobites have discussed the basics of FRBs (here, here, and here for example) but the FRB that the authors of this paper focus on is FRB 181112. FRB 181112 was found with the Australian Square Kilometer Array Pathfinder (ASKAP) and localized to a host galaxy about 2.7 Gpc away from us even though it has not been observed to repeat.

    Australian Square Kilometre Array Pathfinder (ASKAP) is a radio telescope array located at Murchison Radio-astronomy Observatory (MRO) in the Australian Mid West. ASKAP consists of 36 identical parabolic antennas, each 12 metres in diameter, working together as a single instrument with a total collecting area of approximately 4,000 square metres.

    That’s over a hundred times farther away than the closest galaxy cluster, the Virgo Cluster!

    Virgo Supercluster NASA


    Virgo Supercluster, Wikipedia

    One quality of FRB 181112 that makes it particularly interesting to study is that the way ASKAP records data allows the authors to study the polarization of the radio emission. Polarization of light is a measure of how much the electromagnetic wave (here the radio emission) rotates due to any magnetic fields it propagates through. The two types of polarization are linear polarization (Q for vertical/horizontal, or V for ±45°), which occurs if the electromagnetic wave rotates in a plane, and circular (either left- or right-handed depending on the rotation direction) if the light rotates on a circular path. By looking at the polarization of FRB 181112, shown in Figure 1, the authors can determine the strength of the magnetic field it traveled through.

    2
    Figure 1: a) The full polarization profile of FRB 181112 showing four profile components. The black line, I, is the sum of all the polarizations of light, or the total intensity of the burst. The red line, Q, is the profile using only (linearly) horizontally or vertically polarized light; the green line, U, is using only the (linearly) ±45° polarized light; and the blue line, V, is the profile using only circularly polarized light. Negative values describe the direction of the polarization. b) The polarization position angle of the zoomed in profiles from panel (a) seen in panel (c). Variation here suggests the emission is coming from different places in the source. d) A three second time series of the data where the FRB is clearly visible at about 1.8 seconds. [Cho et al. 2020]

    In addition to polarization, the dispersion measure (DM), or difference in time of arrival of the FRB at the telescope between the highest and lowest radio emission frequencies due to its journey through the interstellar medium (ISM), can provide information about the properties of the environment(s) the burst travels through. Each of the four components of FRB 181112 (visible in panel (a) of Figure 1 in three different polarizations, Q, U, and V, as well as total intensity, I) are shown in the bottom row of Figure 2, and each component has a slightly different DM. By looking at how the DM changes, the authors can not only look at different emission processes that could lead these apparent changes, but can also measure how scattered the radio emission of FRB 181112 might be due to the ISM. The intensity of the emission as a function of time and radio frequency for each of the four polarization profiles (I , Q, U, and V) are shown in the top row of Figure 2. The four different components that make up FRB 181112 are shown in total intensity, I, in the bottom row of Figure 2.

    3
    Figure 2: Top row: Intensity of the radio emission of each of the four polarization profiles, I, Q, U, and V (described in Figure 1) as a function of time and radio frequency. Bottom row: Close up of the four different pulse components of the total intensity polarization profile, I, of FRB 181112 as a function of time and radio frequency. All components have been assumed to have a DM of 589.265 pc cm-3 , and a slight slope in the intensity as a function of time and frequency can be seen in pulse 4, indicating it may have a slightly different DM. [Cho et al. 2020]

    Properties of FRB 181112

    4
    Figure 3: Degree of polarization of FRB 181112. The black line (P/I) shows the total polarization, the red line (L/I) shows the linear polarization, and the blue line (V/I) shows the circular polarization. The red and black lines show a large amount of polarization constant in time, while the blue line shows the circular polarization changes over the pulse. [Cho et al. 2020]

    The authors first find that FRB 181112 is highly polarized (see Figures 1 and 3), and while the degree of both the total (P/I) and linear (L/I) polarization is constant across all four components of the pulse, the degree of circular (V/I) polarization varies, as shown in Figure 3. This indicates that the FRB must have either traveled through a relativistic plasma, a cold plasma in the ISM that is moving at relativistic speeds, or that the emission was already highly polarized at the time it was emitted, meaning the source of FRB 181112 would have to be highly magnetized. However if the source of the polarization is due to the plasma in the ISM, the expected polarization would be almost completely linear (Q or U), whereas we observe significant circular polarization (V).

    The authors next analyzed the four different components shown in the bottom row of Figure 2 for variations in DM and find there are some small, but significant differences between each component. These differences could be due to some unmodeled structure in the ISM, again possibly a relativistic plasma, but is unlikely since the burst lasts for only 2 milliseconds. The authors also suggest these differences in DM could be due to gravitational lensing, the radio light being bent around a massive object.

    Gravitational Lensing

    Gravitational Lensing NASA/ESA

    This would mean different components travel through different paths in the ISM, accounting for the different DMs and four different components. However, gravitational lensing cannot explain the high degree of polarization seen in FRB 181112.

    The Million Dollar Question

    So how was FRB 181112 made? What caused the polarization and differences in DM? Well, the authors can’t say anything for certain. They suggest that the most likely model is a relativistic plasma close to the source of the emission, which has polarization properties similar to known magnetars (highly magnetized neutron stars known to emit radio bursts), but none of their models can fully explain all of the different properties of FRB 181112. The source of FRB 181112 remains a mystery for now, but with the huge number of FRBs now being detected, the answer may lie just around the corner.

    See the full article here .


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    What do we do?

    Astrobites is a daily astrophysical literature journal written by graduate students in astronomy. Our goal is to present one interesting paper per day in a brief format that is accessible to undergraduate students in the physical sciences who are interested in active research.
    Why read Astrobites?

    Reading a technical paper from an unfamiliar subfield is intimidating. It may not be obvious how the techniques used by the researchers really work or what role the new research plays in answering the bigger questions motivating that field, not to mention the obscure jargon! For most people, it takes years for scientific papers to become meaningful.
    Our goal is to solve this problem, one paper at a time. In 5 minutes a day reading Astrobites, you should not only learn about one interesting piece of current work, but also get a peek at the broader picture of research in a new area of astronomy.

     
  • richardmitnick 11:37 am on March 27, 2020 Permalink | Reply
    Tags: , , , , , , , FRB's Fast radio Bursts,   

    From AAS NOVA: ” Signals from Neutron Star Binaries” 

    AASNOVA

    From AAS NOVA

    27 March 2020
    Tarini Konchady

    1
    Artist’s illustration of a binary star system consisting of two highly magnetized neutron stars. [John Rowe Animations]

    Fast radio bursts (FRBs) are brief radio signals that last on the order of milliseconds. They appear to be extragalactic, coming from small, point-like areas on the sky. Some FRBs are one-off events, while others are periodic or “repeating”. The sources of FRBs are still unknown, but binary neutron star systems might be a piece of the puzzle.

    Wanted: A Reliable Source of Repeating Fast Radio Bursts

    Any proposed model for a repeating FRB must explain a number of observed behaviors. Among them are the following:

    Repeating bursts from a given FRB source are consistent in frequency and overall intensity on the timescale of years.
    Bursts exhibit small-scale variations in measures of the source’s magnetic environment.
    FRBs seem to be preferentially hosted in massive, Milky-Way-like galaxies.

    2
    Example of an FRB from a repeating source, showing the intensity and various frequencies contained in a single burst (darker means more intense, lighter means less intense). The red lines just below and above 550 MHz and those near 450 MHz and 650 MHz indicate frequencies that were unused due to other radio signals interfering [adapted from the CHIME/FRB Collaboration, Andersen et al. 2019].

    CHIME Canadian Hydrogen Intensity Mapping Experiment -A partnership between the University of British Columbia, the University of Toronto, McGill University, Yale and the National Research Council in British Columbia, at the Dominion Radio Astrophysical Observatory in Penticton, British Columbia, CA Altitude 545 m (1,788 ft)

    Binary neutron stars (BNSs) have been considered as possible solutions to the repeating FRB puzzle. Specifically, binary neutron star mergers might produce FRBs, along with gamma-ray bursts and gravitational waves. But how could BNSs produce repeating, consistent FRBs?

    In a recent study, Bing Zhang (University of Nevada Las Vegas; Kyoto University, Japan) attempts to explain repeating FRBs using BNSs in a novel way. Instead of considering the neutron-star merger itself, Zhang examined whether the years leading up to the merger could produce repeating FRBs.

    A Magnetic Dance

    Repeating FRBs put out an enormous amount of energy over a few milliseconds — at least as much energy as the Sun puts out over three days. To put constraints on the average FRB-producing BNS, Zhang used the double-pulsar system PSR J0737-3039A/B (pulsars are fast-rotating neutron stars with strong magnetic fields), which is very well characterized in terms of its component stars and overall structure.

    Aside from having enormous amounts of rotational energy intrinsically and in their orbits, BNSs also have strong magnetic fields. These magnetic fields are key to the production of FRBs in Zhang’s scenario — as the neutron stars orbit each other, their magnetic fields interact, possibly triggering a flow of particles that would produce FRBs.

    On the scale of centuries or even decades pre-merger, these triggers could occur repeatedly and consistently, satisfying a key requirement for repeating FRBs. This picture of interacting magnetic fields would also explain the small-scale variations in the magnetic environment measures, and there is an overlap between the sorts of galaxies that host FRBs and those that host the gamma-ray bursts that could be associated with BNS mergers.

    By Way of Gravitational Waves

    An observational test for this scenario is the detection of gravitational waves from an FRB source. Space-based gravitational wave detectors, such as the Laser Interferometer Space Antenna, would be well-suited for this.

    Gravity is talking. Lisa will listen. Dialogos of Eide

    ESA/NASA eLISA space based, the future of gravitational wave research

    Ground-based detectors would also play a role, picking up waves from the BNSs actually merging.

    MIT /Caltech Advanced aLigo


    VIRGO Gravitational Wave interferometer, near Pisa, Italy

    And of course, the more FRBs we observe, the more we can narrow down their properties and sources. Fortunately, the Canadian Hydrogen Intensity Mapping Experiment (CHIME) is predicted to detect 2 to 50 FRBs per day, and other radio telescopes are hard at work as well. So maybe this FRB mystery will be solved sooner than we think!

    Citation

    “Fast Radio Bursts from Interacting Binary Neutron Star Systems,” Bing Zhang 2020 ApJL 890 L24.

    https://iopscience.iop.org/article/10.3847/2041-8213/ab7244

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    1

    AAS Mission and Vision Statement

    The mission of the American Astronomical Society is to enhance and share humanity’s scientific understanding of the Universe.

    The Society, through its publications, disseminates and archives the results of astronomical research. The Society also communicates and explains our understanding of the universe to the public.
    The Society facilitates and strengthens the interactions among members through professional meetings and other means. The Society supports member divisions representing specialized research and astronomical interests.
    The Society represents the goals of its community of members to the nation and the world. The Society also works with other scientific and educational societies to promote the advancement of science.
    The Society, through its members, trains, mentors and supports the next generation of astronomers. The Society supports and promotes increased participation of historically underrepresented groups in astronomy.
    The Society assists its members to develop their skills in the fields of education and public outreach at all levels. The Society promotes broad interest in astronomy, which enhances science literacy and leads many to careers in science and engineering.

    Adopted June 7, 2009

     
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