Tagged: Radio Astronomy Toggle Comment Threads | Keyboard Shortcuts

  • richardmitnick 11:20 am on January 16, 2022 Permalink | Reply
    Tags: "Persistent radio source QRS121102 investigated in detail", , A persistent radio source known as QRS121102 that is associated with the fast radio burst FRB 121102., , , , FRB 121102 is the first repeating fast radio burst detected and one of the most extensively studied FRB sources., , Radio Astronomy, , The physical nature of FRBs is yet unknown.   

    From The California Institute of Technology (US) via phys.org : “Persistent radio source QRS121102 investigated in detail” 

    Caltech Logo

    From The California Institute of Technology (US)

    via

    phys.org

    January 11, 2022
    Tomasz Nowakowski

    1
    VLA images (in J2000 coordinates) of QRS121102 in seven epochs, with band indicated in parentheses. Credit: Ge Chen et al., 2022.

    National Radio Astronomy Observatory(US)Karl G Jansky Very Large Array located in central New Mexico on the Plains of San Agustin, between the towns of Magdalena and Datil, ~50 miles (80 km) west of Socorro. The VLA comprises twenty-eight 25-meter radio telescopes.

    Astronomers from the California Institute of Technology (Caltech) have investigated a persistent radio source known as QRS121102 that is associated with the fast radio burst FRB 121102. Results of the study, published January 4 in The Astrophysical Journal, shed more light on the origin of this source and could help us better understand the nature of fast radio bursts.

    Fast radio bursts (FRBs) are intense bursts of radio emission lasting milliseconds and showcasing characteristic dispersion sweep of radio pulsars. The physical nature of these bursts is yet unknown, and astronomers consider a variety of explanations ranging from synchrotron maser emission from young magnetars in supernova remnants to cosmic string cusps.

    FRB 121102 is the first repeating fast radio burst detected and one of the most extensively studied FRB sources. It exhibits complex burst morphology, sub-burst downward frequency drifts, and also complex pulse phenomenology. FRB 121102 is also one of only two FRBs reported to be spatially associated with persistent radio emission of unknown origin.

    A team of astronomers led by Caltech’s Ge Chen took a closer look at this persistent radio source. For this purpose, they observed QRS121102 with the G. Jansky Very Large Array (VLA)[above] and the Low-Resolution Imaging Spectrometer (LRIS) at the Keck Observatory.

    UCO Keck LRIS on Keck 1.

    W.M. Keck Observatory two ten meter telescopes operated by California Institute of Technology(US) and The University of California(US), at Mauna Kea Observatory, Hawaii USA, altitude 4,207 m (13,802 ft). Credit: Caltech.

    “In this work, we investigated the origin of the persistent radio source, QRS121102, associated with FRB 121102. We present new VLA monitoring data (12 to 26 GHz) and new spectra from Keck/LRIS,” the researchers wrote in the paper.

    The observations allowed the team to estimate the physical size of QRS121102. It was found that the emission radius is most likely between 0.1 and 1 light year. Such a relatively small size suggests a few compact radio source candidates, for instance, active galactic nuclei (AGN), pulsar wind nebulae (PWNe), very young supernova remnants (SNRs) and gamma-ray burst (GRB) afterglows.

    Given that QRS121102 may be an AGN, the astronomers constrained the mass of the potential black hole. They found that this mass would be lower than 100,000 solar masses, which does not support the AGN scenario as this source is too faint in the X-ray for its calculated low black hole mass and bright radio emission.

    The radio luminosity of QRS121102, from 400 MHz to 10 GHz, was measured to be approximately 20 billion TW/Hz. Therefore, according to the researchers, this source is too luminous to be an SNR. It was added that QRS121102 is also too bright to be a long-duration GRB (LGRB) radio afterglow.

    Summing up the results, the researchers noted that it is too early to draw final conclusions regarding the true origin of QRS121102 and further observations are required in order to get more insights into the nature of this source.

    “We urge continued broadband radio monitoring of QRS121102 to search for long-term evolution, and the detailed evaluation of potential analogs that may provide greater insight into the nature of this remarkable, mysterious class of object,” the authors of the paper concluded.

    See the full article here .


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


    Please help promote STEM in your local schools.

    Stem Education Coalition

    Caltech campus

    The The California Institute of Technology (US) is a private research university in Pasadena, California. The university is known for its strength in science and engineering, and is one among a small group of institutes of technology in the United States which is primarily devoted to the instruction of pure and applied sciences.

    The California Institute of Technology was founded as a preparatory and vocational school by Amos G. Throop in 1891 and began attracting influential scientists such as George Ellery Hale, Arthur Amos Noyes, and Robert Andrews Millikan in the early 20th century. The vocational and preparatory schools were disbanded and spun off in 1910 and the college assumed its present name in 1920. In 1934, The California Institute of Technology was elected to the Association of American Universities, and the antecedents of National Aeronautics and Space Administration (US)’s Jet Propulsion Laboratory, which The California Institute of Technology continues to manage and operate, were established between 1936 and 1943 under Theodore von Kármán.

    The California Institute of Technology has six academic divisions with strong emphasis on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. First-year students are required to live on campus, and 95% of undergraduates remain in the on-campus House System at The California Institute of Technology. Although The California Institute of Technology has a strong tradition of practical jokes and pranks, student life is governed by an honor code which allows faculty to assign take-home examinations. The The California Institute of Technology Beavers compete in 13 intercollegiate sports in the NCAA Division III’s Southern California Intercollegiate Athletic Conference (SCIAC).

    As of October 2020, there are 76 Nobel laureates who have been affiliated with The California Institute of Technology, including 40 alumni and faculty members (41 prizes, with chemist Linus Pauling being the only individual in history to win two unshared prizes). In addition, 4 Fields Medalists and 6 Turing Award winners have been affiliated with The California Institute of Technology. There are 8 Crafoord Laureates and 56 non-emeritus faculty members (as well as many emeritus faculty members) who have been elected to one of the United States National Academies. Four Chief Scientists of the U.S. Air Force and 71 have won the United States National Medal of Science or Technology. Numerous faculty members are associated with the Howard Hughes Medical Institute(US) as well as National Aeronautics and Space Administration(US). According to a 2015 Pomona College(US) study, The California Institute of Technology ranked number one in the U.S. for the percentage of its graduates who go on to earn a PhD.

    Research

    The California Institute of Technology is classified among “R1: Doctoral Universities – Very High Research Activity”. Caltech was elected to The Association of American Universities in 1934 and remains a research university with “very high” research activity, primarily in STEM fields. The largest federal agencies contributing to research are National Aeronautics and Space Administration(US); National Science Foundation(US); Department of Health and Human Services(US); Department of Defense(US), and Department of Energy(US).

    In 2005, The California Institute of Technology had 739,000 square feet (68,700 m^2) dedicated to research: 330,000 square feet (30,700 m^2) to physical sciences, 163,000 square feet (15,100 m^2) to engineering, and 160,000 square feet (14,900 m^2) to biological sciences.

    In addition to managing NASA-JPL/Caltech (US), The California Institute of Technology also operates the Caltech Palomar Observatory(US); the Owens Valley Radio Observatory(US);the Caltech Submillimeter Observatory(US); the W. M. Keck Observatory at the Mauna Kea Observatory(US); the Laser Interferometer Gravitational-Wave Observatory at Livingston, Louisiana and Richland, Washington; and Kerckhoff Marine Laboratory(US) in Corona del Mar, California. The Institute launched the Kavli Nanoscience Institute at The California Institute of Technology in 2006; the Keck Institute for Space Studies in 2008; and is also the current home for the Einstein Papers Project. The Spitzer Science Center(US), part of the Infrared Processing and Analysis Center(US) located on The California Institute of Technology campus, is the data analysis and community support center for NASA’s Spitzer Infrared Space Telescope [no longer in service].

    The California Institute of Technology partnered with University of California at Los Angeles(US) to establish a Joint Center for Translational Medicine (UCLA-Caltech JCTM), which conducts experimental research into clinical applications, including the diagnosis and treatment of diseases such as cancer.

    The California Institute of Technology operates several Total Carbon Column Observing Network(US) stations as part of an international collaborative effort of measuring greenhouse gases globally. One station is on campus.

     
  • richardmitnick 10:36 pm on January 12, 2022 Permalink | Reply
    Tags: "International collaboration offers new evidence of a gravitational wave background", , , , , EPTA European Pulsar Timing Array, ESA GAIA Release 2 map, ESA/GAIA (Gaia DR2 skymap), In the latest published results now all can clearly recover the common signal., International Pulsar Timing Array (IPTA), NANOGRAV-The North American Nanohertz Observatory for Gravitational Waves(US), PPTA Parkes Pulsar Timing Array, Radio Astronomy, The IPTA is optimistic for what can be achieved once these are combined into the IPTA Data Release 3., The signals from the pulsars measured with a network of global radio telescopes are affected by the gravitational waves and allow for the study of the origin of the background., These signature correlations between pulsar pairs are the “smoking gun” for a gravitational-wave background detection., This data set consists of precision timing data from 65 millisecond pulsars – stellar remnants which spin hundreds of times per second., To identify the gravitational-wave background as the origin of this ultra-low frequency signal the IPTA must also detect spatial correlations between pulsars.   

    From University of Birmingham (UK) : “International collaboration offers new evidence of a gravitational wave background” 

    From The University of Birmingham (UK)

    12 Jan 2022

    Beck Lockwood
    Press Office
    University of Birmingham
    +44 (0)781 3343348.
    r.lockwood@bham.ac.uk

    The results of a comprehensive search for a background of ultra-low frequency gravitational waves has been announced by an international team of astronomers including scientists from the Institute for Gravitational Wave Astronomy at the University of Birmingham.

    1
    Artist impression of the IPTA experiment – An array of pulsars around the Earth embedded in a gravitational wave background from supermassive black hole binaries. The signals from the pulsars measured with a network of global radio telescopes are affected by the gravitational waves and allow for the study of the origin of the background. The distances have been reduced for visual purposes, notably the supermassive black holes are much further away in reality. (Credits: C. Knox)

    These light-year-scale ripples, a consequence of Albert Einstein’s Theory of General Relativity, permeate all of spacetime and could originate from mergers of the most massive black holes in the Universe or from events occurring soon after the formation of the Universe in the Big Bang. Scientists have been searching for definitive evidence of these signals for several decades.

    The International Pulsar Timing Array (IPTA) [EPTA European Pulsar Timing Array; NANOGRAV-The North American Nanohertz Observatory for Gravitational Waves(US);PPTA Parkes Pulsar Timing Array], joining the work of several astrophysics collaborations from around the world, recently completed its search for gravitational waves in their most recent official data release, known as Data Release 2 (DR2), published in MNRAS.

    The river of stars in the southern sky. ESA/GAIA (Gaia DR2 skymap).

    ESA GAIA Release 2 map.

    This data set consists of precision timing data from 65 millisecond pulsars – stellar remnants which spin hundreds of times per second, sweeping narrow beams of radio waves that appear as pulses due to the spinning – obtained by combining the independent data sets from the IPTA’s three founding members: EPTA European Pulsar Timing Array, NANOGRAV-The North American Nanohertz Observatory for Gravitational Waves(US), and PPTA Parkes Pulsar Timing Array.

    These combined data reveal strong evidence for an ultra-low frequency signal detected by many of the pulsars in the combined data. The characteristics of this common-among-pulsars signal are in broad agreement with those expected from a gravitational wave “background”.

    The gravitational wave background is formed by many different overlapping gravitational-wave signals emitted from the cosmic population of supermassive binary black holes (i.e. two supermassive black holes orbiting each other and eventually merging) – similar to background noise from the many overlapping voices in a crowded hall.

    This result further strengthens the gradual emergence of similar signals that have been found in the individual data sets of the participating pulsar timing collaborations over the past few years.

    Professor Alberto Vecchio, Director of the Institute for Gravitational Wave Astronomy at the University of Birmingham, and member of the EPTA, says: “The detection of gravitational waves from a population of massive black hole binaries or from another cosmic source will give us unprecedented insights into how galaxy form and grow, or cosmological processes taking place in the infant universe. A major international effort of the scale of IPTA is needed to reach this goal, and the next few years could bring us a golden age for these explorations of the universe.”

    “This is a very exciting signal! Although we do not have definitive evidence yet, we may be beginning to detect a background of gravitational waves,” says Dr Siyuan Chen, a member of the EPTA and NANOGrav, and the leader of the IPTA DR2 search and publication.

    Dr Boris Goncharov from the PPTA cautions on the possible interpretations of such common signals: “We are also looking into what else this signal could be. For example, perhaps it could result from noise that is present in individual pulsars’ data that may have been improperly modeled in our analyses.”

    To identify the gravitational-wave background as the origin of this ultra-low frequency signal the IPTA must also detect spatial correlations between pulsars. This means that each pair of pulsars must respond in a very particular way to gravitational waves, depending on their separation on the sky.

    These signature correlations between pulsar pairs are the “smoking gun” for a gravitational-wave background detection. Without them, it is difficult to prove that some other process is not responsible for the signal. Intriguingly, the first indication of a gravitational wave background would be a common signal like that seen in the IPTA DR2. Whether or not this spectrally similar ultra-low frequency signal is correlated between pulsars in accordance with the theoretical predictions will be resolved with further data collection, expanded arrays of monitored pulsars, and continued searches of the resulting longer and larger data sets.

    Consistent signals like the one recovered with the IPTA analysis have also been published in individual data sets more recent than those used in the IPTA DR2, from each of the three founding collaborations. The IPTA DR2 analysis demonstrates the power of the international combination giving strong evidence for a gravitational wave background compared to the marginal or absent evidences from the constituent data sets. Additionally, new data from the MeerKAT telescope and from the Indian Pulsar Timing Array (InPTA), the newest member of the IPTA, will further expand future data sets.

    “The first hint of a gravitational wave background would be a signal like that seen in the IPTA DR2. Then, with more data, the signal will become more significant and will show spatial correlations, at which point we will know it is a gravitational wave background. We are very much looking forward to contributing several years of new data to the IPTA for the first time, to help achieve a gravitational wave background detection,” says Dr Bhal Chandra Joshi, a member of the InPTA.

    Given the latest published results from the individual groups who now all can clearly recover the common signal, the IPTA is optimistic for what can be achieved once these are combined into the IPTA Data Release 3. Work is already ongoing on this new data release, which at a minimum will include updated data sets from the four constituent PTAs of the IPTA. The analysis of the DR3 data set is expected to finish within the next few years.

    Gaia EDR3 StarTrails 600

    Dr Maura McLaughlin of the NANOGrav collaboration says, “If the signal we are currently seeing is the first hint of a gravitational wave background, then based on our simulations, it is possible we will have more definite measurements of the spatial correlations necessary to conclusively identify the origin of the common signal in the near future.”

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    University of Birmingham (UK) has been challenging and developing great minds for more than a century. Characterised by a tradition of innovation, research at the University has broken new ground, pushed forward the boundaries of knowledge and made an impact on people’s lives. We continue this tradition today and have ambitions for a future that will embed our work and recognition of the Birmingham name on the international stage.

    The University of Birmingham is a public research university located in Edgbaston, Birmingham, United Kingdom. It received its royal charter in 1900 as a successor to Queen’s College, Birmingham (founded in 1825 as the Birmingham School of Medicine and Surgery), and Mason Science College (established in 1875 by Sir Josiah Mason), making it the first English civic or ‘red brick’ university to receive its own royal charter. It is a founding member of both the Russell Group (UK) of British research universities and the international network of research universities, Universitas 21.

    The student population includes 23,155 undergraduate and 12,605 postgraduate students, which is the 7th largest in the UK (out of 169). The annual income of the institution for 2019–20 was £737.3 million of which £140.4 million was from research grants and contracts, with an expenditure of £667.4 million.

    The university is home to the Barber Institute of Fine Arts, housing works by Van Gogh, Picasso and Monet; the Shakespeare Institute; the Cadbury Research Library, home to the Mingana Collection of Middle Eastern manuscripts; the Lapworth Museum of Geology; and the 100-metre Joseph Chamberlain Memorial Clock Tower, which is a prominent landmark visible from many parts of the city. Academics and alumni of the university include former British Prime Ministers Neville Chamberlain and Stanley Baldwin, the British composer Sir Edward Elgar and eleven Nobel laureates.

    Scientific discoveries and inventions

    The university has been involved in many scientific breakthroughs and inventions. From 1925 until 1948, Sir Norman Haworth was Professor and Director of the Department of Chemistry. He was appointed Dean of the Faculty of Science and acted as Vice-Principal from 1947 until 1948. His research focused predominantly on carbohydrate chemistry in which he confirmed a number of structures of optically active sugars. By 1928, he had deduced and confirmed the structures of maltose, cellobiose, lactose, gentiobiose, melibiose, gentianose, raffinose, as well as the glucoside ring tautomeric structure of aldose sugars. His research helped to define the basic features of the starch, cellulose, glycogen, inulin and xylan molecules. He also contributed towards solving the problems with bacterial polysaccharides. He was a recipient of the Nobel Prize in Chemistry in 1937.

    The cavity magnetron was developed in the Department of Physics by Sir John Randall, Harry Boot and James Sayers. This was vital to the Allied victory in World War II. In 1940, the Frisch–Peierls memorandum, a document which demonstrated that the atomic bomb was more than simply theoretically possible, was written in the Physics Department by Sir Rudolf Peierls and Otto Frisch. The university also hosted early work on gaseous diffusion in the Chemistry department when it was located in the Hills building.

    Physicist Sir Mark Oliphant made a proposal for the construction of a proton-synchrotron in 1943, however he made no assertion that the machine would work. In 1945, phase stability was discovered; consequently, the proposal was revived, and construction of a machine that could surpass proton energies of 1 GeV began at the university. However, because of lack of funds, the machine did not start until 1953. The DOE’s Brookhaven National Laboratory (US) managed to beat them; they started their Cosmotron in 1952, and had it entirely working in 1953, before the University of Birmingham.

    In 1947, Sir Peter Medawar was appointed Mason Professor of Zoology at the university. His work involved investigating the phenomenon of tolerance and transplantation immunity. He collaborated with Rupert E. Billingham and they did research on problems of pigmentation and skin grafting in cattle. They used skin grafting to differentiate between monozygotic and dizygotic twins in cattle. Taking the earlier research of R. D. Owen into consideration, they concluded that actively acquired tolerance of homografts could be artificially reproduced. For this research, Medawar was elected a Fellow of the Royal Society. He left Birmingham in 1951 and joined the faculty at University College London (UK), where he continued his research on transplantation immunity. He was a recipient of the Nobel Prize in Physiology or Medicine in 1960.

     
  • richardmitnick 9:45 am on January 3, 2022 Permalink | Reply
    Tags: "The Tiny Dots in This Image Aren't Stars or Galaxies. They're Black Holes", , , , , LOFAR/LOL Survey, LoLSS: LOFAR LBA Sky Survey, Radio Astronomy, , The Leiden University [Universiteit Leiden] (NL), The University of Hamburg [Universität Hamburg] (DE)   

    From The University of Hamburg [Universität Hamburg] (DE) and The Leiden University [Universiteit Leiden] (NL) via Science Alert (US) : “The Tiny Dots in This Image Aren’t Stars or Galaxies. They’re Black Holes” 

    1
    From The University of Hamburg [Universität Hamburg] (DE)

    and

    The Leiden University [Universiteit Leiden] (NL)

    via

    ScienceAlert

    Science Alert (US)

    2 JANUARY 2022
    MICHELLE STARR

    1
    Credit: LOFAR/LOL Survey.

    The image above may look like a fairly normal picture of the night sky, but what you’re looking at is a lot more special than just glittering stars. Each of those white dots is an active supermassive black hole.

    And each of those black holes is devouring material at the heart of a galaxy millions of light-years away – that’s how they could be pinpointed at all.

    Totaling 25,000 such dots, astronomers created the most detailed map to date of black holes at low radio frequencies in early 2021, an achievement that took years and a Europe-sized radio telescope to compile.

    “This is the result of many years of work on incredibly difficult data,” explained astronomer Francesco de Gasperin [Astronomy & Astrophysics] of the University of Hamburg in Germany. “We had to invent new methods to convert the radio signals into images of the sky.”

    2
    Credit: LOFAR/LOL Survey.

    When they’re just hanging out not doing much, black holes don’t give off any detectable radiation, making them much harder to find. When a black hole is actively accreting material – spooling it in from a disc of dust and gas that circles it much as water circles a drain [Physical Review Letters] – the intense forces involved generate radiation across multiple wavelengths that we can detect across the vastness of space.

    What makes the above image so special is that it covers the ultra-low radio wavelengths, as detected by the LOw Frequency ARray (LOFAR) in Europe. This interferometric network consists of around 20,000 radio antennas, distributed throughout 52 locations across Europe.

    ASTRON Institute for Radio Astronomy(NL) LOFAR Radio Antenna Bank(NL)

    ASTRON (NL) LOFAR European Map.

    Currently, LOFAR is the only radio telescope network capable of deep, high-resolution imaging at frequencies below 100 megahertz, offering a view of the sky like no other. This data release, covering four percent of the Northern sky, was the first for the network’s ambitious plan to image the entire Northern sky in ultra-low-frequencies, the LOFAR LBA Sky Survey (LoLSS).

    Because it’s based on Earth, LOFAR does have a significant hurdle to overcome that doesn’t afflict space-based telescopes: the ionosphere. This is particularly problematic for ultra-low-frequency radio waves [Astronomy & Astrophysics], which can be reflected back into space. At frequencies below 5 megahertz, the ionosphere is opaque for this reason.

    The frequencies that do penetrate the ionosphere can vary according to atmospheric conditions. To overcome this problem, the team used supercomputers running algorithms to correct for ionospheric interference every four seconds. Over the 256 hours that LOFAR stared at the sky, that’s a lot of corrections.

    This is what has given us such a clear view of the ultra-low-frequency sky.

    “After many years of software development, it is so wonderful to see that this has now really worked out,” said astronomer Huub Röttgering of The Leiden Observatory [Sterrewacht Leiden](NL).

    Having to correct for the ionosphere has another benefit, too: It will allow astronomers to use LoLSS data to study the ionosphere itself. Ionospheric traveling waves, scintillations, and the relationship of the ionosphere with solar cycles could be characterized in much greater detail with the LoLSS. This will allow scientists to better constrain ionospheric models.

    And the survey will provide new data on all sorts of astronomical objects and phenomena, as well as possibly undiscovered or unexplored objects in the region below 50 megahertz.

    “The final release of the survey will facilitate advances across a range of astronomical research areas,” the researchers wrote in their paper.

    “[This] will allow for the study of more than 1 million low-frequency radio spectra, providing unique insights on physical models for galaxies, active nuclei, galaxy clusters, and other fields of research. This experiment represents a unique attempt to explore the ultra-low frequency sky at a high angular resolution and depth.”

    The results have been published in Astronomy & Astrophysics.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Universiteit Leiden Heijmans onderhoudt.

    The Leiden University [Universiteit Leiden] (NL) is a public research university in Leiden, Netherlands. Founded in 1575 by William, Prince of Orange as a reward to the town of Leiden for its defense against Spanish attacks during the Eighty Years’ War, it is the oldest institution of higher education in the Netherlands.

    Known for its historic foundations and emphasis on the social sciences, the university came into particular prominence during the Dutch Golden Age, when scholars from around Europe were attracted to the Dutch Republic due to its climate of intellectual tolerance and Leiden’s international reputation. During this time, Leiden became the home to individuals such as René Descartes, Rembrandt, Christiaan Huygens, Hugo Grotius, Baruch Spinoza and Baron d’Holbach.

    The university has seven academic faculties and over fifty subject departments while housing more than 40 national and international research institutes. Its historical primary campus consists of buildings scattered across the college town of Leiden, while a second campus located in The Hague houses a liberal arts college and several of its faculties. It is a member of The Coimbra Group Universities(EU), The Europaeum, and a founding member of The League of European Research Universities (EU).

    Leiden University consistently ranks among the top 100 universities in the world by major ranking tables. It was placed top 50 worldwide in thirteen fields of study in the 2020 QS World University Rankings: classics & ancient history, politics, archaeology, anthropology, history, pharmacology, law, public policy, public administration, religious studies, arts & humanities, linguistics, modern languages and sociology.

    The school has produced twenty-one Spinoza Prize Laureates and sixteen Nobel Laureates, including Enrico Fermi and Albert Einstein. It is closely associated with the Dutch Royal Family, with Queen Juliana, Queen Beatrix and King Willem-Alexander being alumni. Ten prime ministers of the Netherlands were also Leiden University alumni. Internationally, it is associated with nine foreign leaders, among them John Quincy Adams (the 6th President of the United States), two NATO Secretaries General, a President of the International Court of Justice, and a Prime Minister of the United Kingdom.

    In 1575, the emerging Dutch Republic did not have any universities in its northern heartland. The only other university in the Habsburg Netherlands was the University of Leuven [Universiteit Leuven](BE) in southern Leuven, firmly under Spanish control. The scientific renaissance had begun to highlight the importance of academic study, so Prince William founded the first Dutch university in Leiden, to give the Northern Netherlands an institution that could educate its citizens for religious purposes, but also to give the country and its government educated men in other fields. It is said the choice fell on Leiden as a reward for the heroic defence of Leiden against Spanish attacks in the previous year. Ironically, the name of Philip II of Spain, William’s adversary, appears on the official foundation certificate, as he was still the de jure count of Holland. Philip II replied by forbidding any subject to study in Leiden. Originally located in the convent of St Barbara, the university moved to the Faliede Bagijn Church in 1577 (now the location of the University museum) and in 1581 to the convent of the White Nuns, a site which it still occupies, though the original building was destroyed by fire in 1616.

    The presence within half a century of the date of its foundation of such scholars as Justus Lipsius; Joseph Scaliger; Franciscus Gomarus; Hugo Grotius; Jacobus Arminius; Daniel Heinsius; and Gerhard Johann Vossius rapidly made Leiden university into a highly regarded institution that attracted students from across Europe in the 17th century. Renowned philosopher Baruch Spinoza was based close to Leiden during this period and interacted with numerous scholars at the university. The learning and reputation of Jacobus Gronovius; Herman Boerhaave; Tiberius Hemsterhuis; and David Ruhnken, among others, enabled Leiden to maintain its reputation for excellence down to the end of the 18th century.

    At the end of the nineteenth century, Leiden University again became one of Europe’s leading universities. In 1896 the Zeeman effect was discovered there by Pieter Zeeman and shortly afterwards given a classical explanation by Hendrik Antoon Lorentz. At the world’s first university low-temperature laboratory, professor Heike Kamerlingh Onnes achieved temperatures of only one degree above absolute zero of −273 degrees Celsius. In 1908 he was also the first to succeed in liquifying helium and can be credited with the discovery of the superconductivity in metals.

    The University Library, which has more than 5.2 million books and fifty thousand journals, also has a number of internationally renowned special collections of western and oriental manuscripts, printed books, archives, prints, drawings, photographs, maps, and atlases. It houses the largest collections worldwide on Indonesia and the Caribbean. The research activities of the Scaliger Institute focus on these special collections and concentrate particularly on the various aspects of the transmission of knowledge and ideas through texts and images from antiquity to the present day.

    In 2005 the manuscript of Einstein on the quantum theory of the monatomic ideal gas (the Einstein-Bose condensation) was discovered in one of Leiden’s libraries.

    2

    The University of Hamburg [Universität Hamburg] (DE) is the largest institution for research and education in northern Germany. As one of the country’s largest universities, we offer a diverse range of degree programs and excellent research opportunities. The University boasts numerous interdisciplinary projects in a broad range of fields and an extensive partner network of leading regional, national, and international higher education and research institutions.

    Sustainable science and scholarship

    Universität Hamburg is committed to sustainability. All our faculties have taken great strides towards sustainability in both research and teaching.

    Excellent research

    As part of the Excellence Strategy of the Federal and State Governments, Universität Hamburg has been granted clusters of excellence for 4 core research areas: Advanced Imaging of Matter (photon and nanosciences), Climate, Climatic Change, and Society (CliCCS) (climate research), Understanding Written Artefacts (manuscript research) and Quantum Universe (mathematics, particle physics, astrophysics, and cosmology).

    An equally important core research area is Infection Research, in which researchers investigate the structure, dynamics, and mechanisms of infection processes to promote the development of new treatment methods and therapies.

    Outstanding variety: over 170 degree programs

    Universität Hamburg offers approximately 170 degree programs within its eight faculties:

    Faculty of Law
    Faculty of Business, Economics and Social Sciences
    Faculty of Medicine
    Faculty of Education
    Faculty of Mathematics, Informatics and Natural Sciences
    Faculty of Psychology and Human Movement Science
    Faculty of Business Administration (Hamburg Business School).

    Universität Hamburg is also home to several museums and collections, such as the Zoological Museum, the Herbarium Hamburgense, the Geological-Paleontological Museum, the Loki Schmidt Garden, and the Hamburg Observatory.
    History

    Universität Hamburg was founded in 1919 by local citizens. Important founding figures include Senator Werner von Melle and the merchant Edmund Siemers. Nobel Prize winners such as the physicists Otto Stern, Wolfgang Pauli, and Isidor Rabi taught and researched at the University. Many other distinguished scholars, such as Ernst Cassirer, Erwin Panofsky, Aby Warburg, William Stern, Agathe Lasch, Magdalene Schoch, Emil Artin, Ralf Dahrendorf, and Carl Friedrich von Weizsäcker, also worked here.

     
  • richardmitnick 9:14 am on December 26, 2021 Permalink | Reply
    Tags: "Astronomers find Milky Way analogue galaxy in the early universe", "The Cosmic Seahorse" galaxy, , , , , , , Radio Astronomy,   

    From IAC-The Institute of Astrophysics of the Canary Islands [Instituto de Astrofísica de Canarias] (ES) : “Astronomers find Milky Way analogue galaxy in the early universe” 

    Instituto de Astrofísica de Andalucía

    From IAC-The Institute of Astrophysics of the Canary Islands [Instituto de Astrofísica de Canarias] (ES)

    21/12/2021

    1
    Zoom-in on the Cosmic Seahorse in visual and near infrared light. The foreground giant elliptical galaxy, at the center of a galaxy cluster, magnifies and distorts the distant light coming from the strongly lensed galaxy. Credit: NASA/ESA Hubble.

    National Aeronautics and Space Administration(US)/European Space Agency [Agence spatiale européenne] [Europäische Weltraumorganisation](EU) Hubble Space Telescope.

    An international team, including researchers from the Instituto de Astrofísica de Canarias (IAC), used combined data from different radio telescopes located in Spain to probe the mode of star formation in a galaxy when the universe had less than 30% of its current age. They revealed that the properties of the molecular gas reservoir are similar to the one of our own Galaxy, unseen up to now in the distant universe. The paper is published in The Astrophysical Journal Letters.

    A major question in the study of galaxies is on the mode of star formation, how efficient the conversion of cold gas into stars is. Up to now, galaxies in the early universe seem to form stars in a different manner than observed in our own Galaxy which is puzzling. To shed light onto this question, the cold molecular gas, the fuel for the formation of stars, gets observed with radio telescopes.

    Due to the physical properties of the molecular hydrogen gas (H2), it cannot be observed directly in the radio regime but it can traced via the carbon monoxide molecule (CO). And that is what the team led by Nikolaus Sulzenauer, a PhD student at The MPG Institute for Radio Astronomy[MPG Institut für Radioastronomie](DE) has done.

    First, the researchers selected a galaxy whose brightness is boosted through gravitational lensing by an intervening cluster of galaxies. They then searched for archival data of infrared space missions in combination with the Hubble Space Telescope imaging.

    “The discovered galaxy is strongly lensed by a factor of about 10 and thus its morphology is distorted resembling a seahorse.

    Gravitational Lensing Gravitational Lensing National Aeronautics Space Agency (US) and European Space Agency [Agence spatiale européenne][Europäische Weltraumorganisation](EU).

    Therefore its nickname is “the Cosmic Seahorse” explains Sulzenauer, who carried out this study as a master’s thesis at The University of Vienna [Universität Wien](AT) under the supervision of IAC researcher Helmut Dannerbauer who is also co-author of the paper that is published in The Astrophysical Journal Letters.

    3
    Detail of the “cosmic seahorse”, a galaxy modified by gravitational lensing. Illustration: Carla Nicolin Schoder (Univ. Vienna)

    The researcher revealed the distance of this galaxy, the light travelled 9.6 billion years, through observations of the carbon monoxide lines with the 30 m radio telescope of the Instituto de Radioastronomía Milimétrica (IRAM) located in the Sierra Nevada.

    IRAM 30m Radio telescope in Spain.

    Together with observations of the Yebes 40 m radio telescope located at Yebes, 50 km north-east of Madrid and operated by the Instituto Geográfico Nacional (IGN), the physical properties of the fuel of star formation through the observations of several molecular gas lines could be derived as well.

    4
    Yebes 40 m radio telescope located at Yebes, 50 km north-east of Madrid.

    “That it is the most distant galaxy detected with the Yebes 40 m radio telescope up to now” notes Dannerbauer, who also highlights the advantage that the method used in the research has brought to these radio telescopes: “The gravitational lensing virtually transforms the IRAM and Yebes telescopes into radio telescopes with sizes of single dishes of 300 resp. 400 m, impossible to construct.”

    Through the analysis of the cold molecular gas, the researchers found the presence of previously unseen star-formation mechanism at cosmic noon, the peak epoch of star formation and black hole activity of the universe. “Our research has shown that this is a so-called main-sequence galaxy with slowly evolving star formation at the epoch of maximum star formation in the Universe” adds Bodo Ziegler from the University of Vienna and co-author of the article.

    “This seems to be the missing link between systems with high and low star formation rate such as the Cosmic Seahorse” explains Anastasio Díaz Sánchez of The Polytechnic University of Cartagena[Universidad Politécnica de Cartagena](ES) who also participated in the study. Likewise, Susana Iglesias Groth, IAC researcher and co-author of the article, emphasises the relevance of this discovery considering the difficulty of studying this type of galaxy: “Without the gravitational lensing it would have been impossible to detect this galaxy, with calm star formation activity, with these large radio telescopes.”

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    IAC-The Institute of Astrophysics of the Canary Islands [Instituto de Astrofísica de Canarias] (ES) operates two astronomical observatories in the Canary Islands:

    Roque de los Muchachos Observatory on La Palma
    Teide Observatory on Tenerife.

    The Instituto de Astrofísica the headquarters, which is in La Laguna (Tenerife).

    Observatorio del Roque de los Muchachos at La Palma (ES) at an altitude of 2400m.

    The seeing statistics at ORM make it the second-best location for optical and infrared astronomy in the Northern Hemisphere, after Mauna Kea Observatory Hawaii (US).

    Maunakea Observatories Hawai’i (US) altitude 4,213 m (13,822 ft).

    The site also has some of the most extensive astronomical facilities in the Northern Hemisphere; its fleet of telescopes includes the 10.4 m Gran Telescopio Canarias, the world’s largest single-aperture optical telescope as of July 2009, the William Herschel Telescope (second largest in Europe), and the adaptive optics corrected Swedish 1-m Solar Telescope.

    Gran Telescopio Canarias [Instituto de Astrofísica de Canarias ](ES) sited on a volcanic peak 2,267 metres (7,438 ft) above sea level.

    Isaac Newton Group 4.2 meter William Herschel Telescope at Roque de los Muchachos Observatory on La Palma in the Canary Islands(ES), 2,396 m (7,861 ft).

    The Swedish 1m Solar Telescope SST at the Roque de los Muchachos observatory on La Palma Spain, Altitude 2,360 m (7,740 ft).

    The observatory was established in 1985, after 15 years of international work and cooperation of several countries with the Spanish island hosting many telescopes from Britain, The Netherlands, Spain, and other countries. The island provided better seeing conditions for the telescopes that had been moved to Herstmonceux by the Royal Greenwich Observatory, including the 98 inch aperture Isaac Newton Telescope (the largest reflector in Europe at that time). When it was moved to the island it was upgraded to a 100-inch (2.54 meter), and many even larger telescopes from various nations would be hosted there.

    Tiede Observatory, Tenerife, Canary Islands (ES)

    Teide Observatory [Observatorio del Teide], IAU code 954, is an astronomical observatory on Mount Teide at 2,390 metres (7,840 ft), located on Tenerife, Spain. It has been operated by the Instituto de Astrofísica de Canarias since its inauguration in 1964. It became one of the first major international observatories, attracting telescopes from different countries around the world because of the good astronomical seeing conditions. Later the emphasis for optical telescopes shifted more towards Roque de los Muchachos Observatory on La Palma.

     
  • richardmitnick 1:13 pm on December 24, 2021 Permalink | Reply
    Tags: "Astronomers capture black hole eruption spanning 16 times the full Moon in the sky", , , , CCA: "Chaotic Cold Accretion", Centaurus A is the closest radio galaxy to our own Milky Way., , Radio Astronomy, SKA and SARAO, The black hole vigorously reacts by launching energy back via radio jets that inflate the spectacular lobes we see in the MWA image., The image reveals spectacular new details of the radio emission from the galaxy., , The Murchison Widefield Array is a precursor for the Square Kilometre Array (SKA)., These radio waves come from material being sucked into the supermassive black hole in the middle of the galaxy.   

    From The International Centre for Radio Astronomy Research – ICRAR (AU): “Astronomers capture black hole eruption spanning 16 times the full Moon in the sky” 

    ICRAR Logo

    From The International Centre for Radio Astronomy Research – ICRAR (AU)

    December 23, 2021

    Pete Wheeler
    ICRAR
    Pete.Wheeler@icrar.org
    +61 423 982 018

    Lucien Wilkinson
    Curtin University
    Lucien.Wilkinson@curtin.edu.au
    +61 413 070 925

    Astronomers have produced the most comprehensive image of radio emission from the nearest actively feeding supermassive black hole to Earth.

    The emission is powered by a central black hole in the galaxy Centaurus A, about 12 million light years away.

    1
    Centaurus A is a giant elliptical active galaxy 12 million light-years away. At its heart lies a black hole with a mass of 55 million suns. This image shows the galaxy at radio wavelengths, revealing vast lobes of plasma that reach far beyond the visible galaxy, which occupies only a small patch at the centre of the image. The dots in the background are not stars, but radio galaxies much like Centaurus A, at far greater distances. Credit: Ben McKinley, ICRAR/Curtin and Connor Matherne, The Louisiana State University (US).

    As the black hole feeds on in-falling gas, it ejects material at near light-speed, causing ‘radio bubbles’ to grow over hundreds of millions of years.

    Extending above and below the Milky Way’s disc are Fermi bubbles, enormous round structures of hot gas emanating from the galactic center.

    When viewed from Earth, the eruption from Centaurus A now extends eight degrees across the sky—the length of 16 full Moons laid side by side.

    It was captured using the Murchison Widefield Array (MWA) [below] telescope in outback Western Australia.

    The research was published today in the journal Nature Astronomy.

    Lead author Dr Benjamin McKinley, from the Curtin University node of the International Centre for Radio Astronomy Research (ICRAR), said the image reveals spectacular new details of the radio emission from the galaxy.

    “These radio waves come from material being sucked into the supermassive black hole in the middle of the galaxy,” he said.

    “It forms a disc around the black hole, and as the matter gets ripped apart going close to the black hole, powerful jets form on either side of the disc, ejecting most of the material back out into space, to distances of probably more than a million light years.

    “Previous radio observations could not handle the extreme brightness of the jets and details of the larger area surrounding the galaxy were distorted, but our new image overcomes these limitations.”

    Centaurus A is the closest radio galaxy to our own Milky Way.

    “We can learn a lot from Centaurus A in particular, just because it is so close and we can see it in such detail,” Dr McKinley said.

    “Not just at radio wavelengths, but at all other wavelengths of light as well.

    “In this research we’ve been able to combine the radio observations with optical and x-ray data, to help us better understand the physics of these supermassive black holes.”

    2
    Centaurus A is a giant elliptical active galaxy 12 million light-years away. At its heart lies a black hole with a mass of 55 million suns. This composite image shows the galaxy and the surrounding intergalactic space at several different wavelengths. The radio plasma is displayed in blue and appears to be interacting with hot X-ray emitting gas (orange) and cold neutral hydrogen (purple). Clouds emitting Halpha (red) are also shown above the main optical part of the galaxy which lies in between the two brightest radio blobs. The ‘background’ is at optical wavelengths, showing stars in our own Milky Way that are actually in the foreground. Credit: Connor Matherne, Louisiana State University (Optical/Halpha), Kraft et al. (X-ray), Struve et al. (HI), Ben McKinley, ICRAR/Curtin. (Radio).

    Astrophysicist Dr Massimo Gaspari, from INAF Italian National Institute for Astrophysics [Istituto Nazionale di Astrofisica](IT), said the study corroborated a novel theory known as “Chaotic Cold Accretion” (CCA), which is emerging in different fields.

    “In this model, clouds of cold gas condense in the galactic halo and rain down onto the central regions, feeding the supermassive black hole,” he said.

    “Triggered by this rain, the black hole vigorously reacts by launching energy back via radio jets that inflate the spectacular lobes we see in the MWA image. This study is one of the first to probe in such detail the multiphase CCA ‘weather’ over the full range of scales”, Dr Gaspari concluded.

    Dr McKinley said the galaxy appears brighter in the centre where it is more active and there is a lot of energy.

    “Then it’s fainter as you go out because the energy’s been lost and things have settled down,” he said.

    “But there are interesting features where charged particles have re-accelerated and are interacting with strong magnetic fields.”

    A video showing the radio galaxy, Centaurus A, which hosts the closest actively feeding black hole to Earth. The video shows the apparent size of the galaxy at optical, X-ray and submillimetre wavelengths from Earth when compared to the Moon. It then zooms out to show the enormous extent of the surrounding bubbles that are observed at radio wavelengths. Astronomers have produced the most comprehensive image of radio emission from the nearest actively feeding supermassive black hole to Earth. Find out more at: http://www.icrar.org/centaurus Credit: ESO/WFI (Optical) – MPIfR/ESO/APEX/A. Weiss et al. (Submillimetre) – The National Aeronautics and Space Administration (US)/Chandra X-ray Center (US)/ Harvard-Smithsonian Center for Astrophysics (US)/R.Kraft et al. (X-ray) – Ben McKinley, ICRAR/Curtin and Connor Matherne, Louisiana State University (radio).

    WFI Wide Field Imager on the 2.2 meter MPG/ESO telescope at Cerro LaSilla (CL)

    ESO operates the Atacama Pathfinder Experiment, APEX, for The MPG Institute for Radio Astronomy [MPG Institut für Radioastronomie](DE) at one of the highest observatory sites on Earth, at an elevation of 5100 metres, high on the Chajnantor plateau in Chile’s Atacama region.

    National Aeronautics and Space Administration Chandra X-ray telescope(US)

    MWA director Professor Steven Tingay said the research was possible because of the telescope’s extremely wide field-of-view, superb radio-quiet location, and excellent sensitivity.

    “The MWA is a precursor for the Square Kilometre Array (SKA)—a global initiative to build the world’s largest radio telescopes in Western Australia and South Africa,” he said.

    SKA-Square Kilometer Array

    SKA- South Africa

    “The wide field of view and, as a consequence, the extraordinary amount of data we can collect, means that the discovery potential of every MWA observation is very high. This provides a fantastic step toward the even bigger SKA.”

    4
    Composite image of the SKA-Low telescope in Western Australia. The image blends a real photo (on the left) of the SKA-Low prototype station AAVS2.0 which is already on-site, with an artist’s impression of the future SKA-Low stations as they will look when constructed. These dipole antennas, which will number in their hundreds of thousands, will survey the radio sky at frequencies as low as 50Mhz. Credit: ICRAR, SKAO.

    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 International Centre for Radio Astronomy Research – ICRAR (AU) is an equal joint venture between Curtin University and The University of Western Australia with funding support from the State Government of Western Australia. The Centre’s headquarters are located at UWA, with research nodes at both UWA and the Curtin Institute for Radio Astronomy (CIRA).
    ICRAR(AU) has strong support from the government of Australia and is working closely with industry and the astronomy community, including CSIRO(AU) and the Australian Telescope National Facility, <a
    ICRAR is:

    Playing a key role in the international Square Kilometre Array (SKA) project, the world's biggest ground-based telescope array.

    Attracting some of the world’s leading researchers in radio astronomy, who will also contribute to national and international scientific and technical programs for SKA and ASKAP.

    SKA ASKAP Pathfinder Radio Telescope.

    Creating a collaborative environment for scientists and engineers to engage and work with industry to produce studies, prototypes and systems linked to the overall scientific success of the SKA, MWA and ASKAP.

    SKA Murchison Widefield Array (AU), Boolardy station in outback Western Australia, at the Murchison Radio-astronomy Observatory (MRO), on the traditional lands of the Wajarri peoples.

    A Small part of the Murchison Widefield Array(AU)

    Enhancing Australia’s position in the international SKA program by contributing to the development process for the SKA in scientific, technological and operational areas.
    Promoting scientific, technical, commercial and educational opportunities through public outreach, educational material, training students and collaborative developments with national and international educational organisations.
    Establishing and maintaining a pool of emerging and top-level scientists and technologists in the disciplines related to radio astronomy through appointments and training.
    Making world-class contributions to SKA science, with emphasis on the signature science themes associated with surveys for neutral hydrogen and variable (transient) radio sources.
    Making world-class contributions to SKA capability with respect to developments in the areas of Data Intensive Science and support for the Murchison Radio-astronomy Observatory.

     
  • richardmitnick 8:24 pm on December 20, 2021 Permalink | Reply
    Tags: "ALMA’s Most Scientifically Productive Receiver Will Soon See Further than Ever Before", A multi-million dollar upgrade project for the Observatory’s 1.3mm (Band 6) receivers, A wider selection of diagnostic line transitions can be observed simultaneously with better sensitivity than ever before., ALMA will be able to make observations much faster as the new receivers will be much more sensitive., , Band 6v2 will be the first receiver upgraded as a part of the ALMA2030 Development Roadmap., , , , Phase 1 of the project—funded for $7.68 million—aims to produce a prototype receiver by 2026 ., Radio Astronomy, The Band 6v2 upgrade is the first in a long line of upgrades to come that will bring unparalleled sensitivity to this already immensely powerful observatory., , The upgrade will increase the overall wavelength range accessible by the receiver and improve its sensitivity which reduces the observing time required., The wavelength coverage of any one observation will more than double., These new Band 6v2 receivers will increase the quantity and quality of science measured in wavelengths between 1.4mm and 1.1mm.   

    From The National Radio Astronomy Observatory (US) : “ALMA’s Most Scientifically Productive Receiver Will Soon See Further than Ever Before” 

    NRAO Banner

    From The National Radio Astronomy Observatory (US)

    December 17, 2021

    Amy C. Oliver
    Public Information Officer, ALMA
    Public Information & News Manager, NRAO
    +1 434 242 9584
    aoliver@nrao.edu

    Multi-million dollar upgrade will increase sensitivity, seeing distance, and image clarity for Band 6 receivers

    1
    Patricio Escarate, a Cryogenics and Vacuum Technician at the Atacama Large Millimeter/submillimeter Array (ALMA) works on a front end, or chilled cooler that hold the cutting edge receivers for each ALMA antenna. Credit: M. Alexander, The European Southern Observatory [Observatoire européen austral][Europaiche Sûdsternwarte] (EU)(CL)

    The National Science Foundation (US) and the board of The Atacama Large Millimeter/submillimeter Array (ALMA (CL)) have approved a multi-million dollar upgrade project for the Observatory’s 1.3mm (Band 6) receivers through the North American ALMA Development Program. The receivers—originally built, and to be upgraded, by the Central Development Laboratory (CDL) at the National Radio Astronomy Observatory (NRAO)—are the most scientifically productive in ALMA’s lineup. Launching in 2021, Phase 1 of the project—funded for $7.68 million—aims to produce a prototype receiver by 2026 that will allow NRAO to plan for the build-out of an entirely upgraded set of Band 6 receivers for ALMA. These new Band 6v2 receivers will increase the quantity and quality of science measured in wavelengths between 1.4mm and 1.1mm.

    Crystal Brogan, ALMA-North America Program Scientist and the ALMA Development Program Coordinator at NRAO, said that for scientists, the upgrade—which will take place over a decade from design to completion—provides three significant improvements. The wavelength coverage of any one observation will more than double, which will allow many more spectral lines to be observed at once. In addition, the upgrade will increase the overall wavelength range accessible by the receiver and improve its sensitivity which reduces the observing time required. Brogan said, “What this means for scientists is that a wider selection of diagnostic line transitions can be observed simultaneously with better sensitivity than ever before, leading to more accurate and efficient scientific results.”

    The Band 6 upgrade is part of the ambitious “ALMA2030 Wideband Sensitivity Upgrade,” which seeks to at least double and eventually quadruple the correlated bandwidth of the Observatory’s antennas. Band 6v2 will be the first receiver upgraded as a part of the ALMA2030 Development Roadmap. Brogan noted that the receiver was chosen for the first upgrade because “Band 6 is currently ALMA’s most popular band in terms of the number of hours proposed each cycle. We see more ALMA publications reporting results from this band than any other in every observing year.”

    Technologically, the extensive project includes upgrading or replacing virtually every critical subsystem on the receivers, including the feed horn antennas, the polarization separators (also referred to as orthomode transducers, or OMTs), mixers and amplifiers, and local oscillators.

    2
    Extremely weak signals from space are collected by the ALMA antennas and focussed onto receivers, like these two shown here, which transform the faint radiation into an electrical signal. The upgraded Band 6v2 receivers will increase both the quality and quantity of science that ALMA can achieve in the band, allowing for more accurate and efficient science. Credit: ESO.

    3
    Behind the dish of each ALMA antenna sits one of these Front Ends, the chilled coolers that hold the suite of cutting-edge receivers. Each receiver was hand-crafted in one of three different laboratories around the world. They were brought together to be assembled into this cryogenic unit and shipped to Chile for installation inside each of ALMA’s 66 antennas. Credit: P. Carrillo, ALMA (ESO/The National Astronomical Observatory of Japan[[国立天文台](JP)/NRAO)

    The upgrade includes several new or improved technologies resulting from NRAO’s collaboration with The University of Virginia (US)’s Innovations in Fabrication (IFAB) Laboratory. Bert Hawkins, Director of CDL, said, “Our work with UVA includes the development of a new superconducting SIS mixer at the heart of the new receiver that extends the wavelength range the receiver will be sensitive to, thus increasing the scientific capabilities of Band 6. We’re also working together to develop a new class of superconducting hybrid couplers used inside the receiver to separate sidebands in the signal. In addition to our work with UVA, our internal teams are improving upon myriad technologies. Our low-noise amplifier team, for example, is developing a new generation of cryogenically-cooled amplifiers based on a commercially-available transistor.”

    Hawkins added, “The original Band 6 receiver was designed over 20 years ago. Since then, the National Science Foundation has invested in improving millimeter-wave receiver technology through NRAO. This effort has paid off, and now, by leveraging technology developed at CDL and with our partners at the University of Virginia, this upgrade answers the call of the ALMA2030 Development Roadmap to increase the bandwidth and wavelength coverage of ALMA receivers while improving sensitivity.” In addition to continuing a longstanding partnership with UVA, the upgrade will allow ALMA-North America to leverage its existing relationship with the Advanced Manufacturing Initiative at The Piedmont Virginia Community College (US), providing students with hands-on experiences like micro-assembly and wire bonding, the use of small software-defined radios to measure and characterize the electromagnetic spectrum, high-frequency measurements, and cryogenic measurements of electronics.

    “The international ALMA collaboration has a clear view for the future of radio astronomy, and the Band 6v2 upgrade is the first in a long line of upgrades to come that will bring unparalleled sensitivity to this already immensely powerful observatory,” said Tony Beasley, Director of NRAO. “The original Band 6 quickly became the most scientifically productive receiver at ALMA because of its capabilities. With this upgrade from CDL, Band 6v2 will hold that position at ALMA for years to come.”

    ALMA Director Sean Dougherty added, “This is a very exciting upgrade to the most productive receiver system at ALMA. Aside from the phenomenal new science capabilities, ALMA will be able to make observations much faster as the new receivers will be much more sensitive. This will substantially increase the amount of high-quality observations we can deliver to the community.”

    The North American ALMA Development Program is funded by the NSF and The National Research Council Canada [Conseil national de recherches Canada](CA). “These Band 6v2 upgrades point to the fantastic ability to make improvements as technology advances,” said Dr. Joe Pesce, ALMA Program Officer at the National Science Foundation. “The new science capabilities made possible by the upgrades will allow ALMA to remain at the cutting edge of millimeter science.”

    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 Atacama Large Millimeter/submillimeter Array (ALMA) (CL) , an international astronomy facility, is a partnership of Europe, North America and East Asia in cooperation with the Republic of Chile. ALMA is funded in Europe by the European Organization for Astronomical Research in the Southern Hemisphere (ESO), in North America by the U.S. National Science Foundation (NSF) in cooperation with the National Research Council of Canada (NRC) and the National Science Council of Taiwan (NSC) and in East Asia by the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Academia Sinica (AS) in Taiwan.

    ALMA construction and operations are led on behalf of Europe by ESO, on behalf of North America by the National Radio Astronomy Observatory (NRAO), which is managed by Associated Universities, Inc. (AUI) and on behalf of East Asia by the National Astronomical Observatory of Japan (NAOJ). The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

    NRAO Small
    ESO 50 Large

    ALMA is a time machine!

    ALMA-In Search of our Cosmic Origins

    The National Radio Astronomy Observatory (US) is a facility of The National Science Foundation (US), operated under cooperative agreement by The Associated Universities, Inc (US).


    National Radio Astronomy Observatory (US) Karl G Jansky Very Large Array located in central New Mexico on the Plains of San Agustin, between the towns of Magdalena and Datil, ~50 miles (80 km) west of Socorro. The VLA comprises twenty-eight 25-meter radio telescopes.

    ngVLA, to be located near the location of the NRAO Karl G. Jansky Very Large Array (US) site on the plains of San Agustin, fifty miles west of Socorro, NM, USA, at an elevation of 6970 ft (2124 m) with additional mid-baseline stations currently spread over greater New Mexico, Arizona, Texas, and Mexico.

    National Radio Astronomy Observatory (US)Very Long Baseline Array.

    European Southern Observatory [Observatoire européen austral][Europäische Südsternwarte] (EU)/National Radio Astronomy Observatory(US)/National Astronomical Observatory of Japan(JP) ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres.
    Access to ALMA observing time by the North American astronomical community will be through the North American ALMA Science Center (NAASC).

    *The Very Long Baseline Array (VLBA) comprises ten radio telescopes spanning 5,351 miles. It’s the world’s largest, sharpest, dedicated telescope array. With an eye this sharp, you could be in Los Angeles and clearly read a street sign in New York City!

    Astronomers use the continent-sized VLBA to zoom in on objects that shine brightly in radio waves, long-wavelength light that’s well below infrared on the spectrum. They observe blazars, quasars, black holes, and stars in every stage of the stellar life cycle. They plot pulsars, exoplanets, and masers, and track asteroids and planets.

     
  • richardmitnick 12:32 pm on December 20, 2021 Permalink | Reply
    Tags: "Diagnosing Dust Grain Survival in FU Ori", , , , Radio Astronomy,   

    From The National Radio Astronomy Observatory (US) : “Diagnosing Dust Grain Survival in FU Ori” 

    NRAO Banner

    From The National Radio Astronomy Observatory (US)

    12.20.21
    Hauyu Baobab Liu (
    The Academia Sinica Institute of Astronomy and Astrophysics(TW))

    1
    Schematic (top) to show how continuum observations (bottom) may diagnose the dust properties in protoplanetary disks. Adapted from Liu et al. (2021).

    It has long been considered that icy dust aggregates are very sticky. The rapid coagulation of the icy dust aggregates had been regarded as a potential solution to the long-term theoretical problem of how grain growth bypasses the bouncing and inward migration barriers, allowing the formation of centimeter-sized pebbles and kilometer-sized planetesimals (Okuzumi et al. 2012; Drążkowska et al. 2017). However, it is still difficult to understand how the Earth is so seriously deficient in water and carbon (see Bergin et al. 2015 and references therein for further discussion).

    Comparing Jansky Very Large Array (VLA) and Atacama Large Millimeter/submillimeter Array (ALMA) photometric measurements over ~ 1-30 mm wavelengths of an outbursting young stellar object, FU Ori – where dry silicate dust may be present over a spatially extended area – Liu et al. (2021) found that dry silicate grains may be considerably stickier than previously thought (see figure). This result agrees with the latest analytical calculations and laboratory experiments which indicated that dry silicate dust can be as sticky as, or even stickier than, icy dust (Kimura et al. 2015, Gundlach et al. 2018, Steinpilz et al. 2019, Musiolik et al. 2019, Pillich et al. 2021).

    To thoroughly understand the origin and the chemical composition of terrestrial planets and the Earth, it is clearly fundamental to investigate the radial dust surface density profile and the grain size distributions around the water snow lines (~ 170 K). In particular, to robustly test for the presence of icy or dry pebbles/chondrules and to map their spatial distributions, it is crucial to examine the spectral signatures of such “grown” dust at ~ 1-100 mm wavelengths. This is challenging with current observing facilities given that the water snow lines in the majority of protoplanetary disks are typically only around 1 AU from the host protostars (Mori et al. 2021).

    The next generation Very Large Array (ngVLA) will uniquely be the facility to resolve the nearby (e.g., < 150 pc) protoplanetary disks at the desired wavelengths with sub-AU spatial resolutions. It is expected that the ngVLA data will anchor the most important aspects in the theories of terrestrial planet-formation.

    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 National Radio Astronomy Observatory (US) is a facility of The National Science Foundation (US), operated under cooperative agreement by The Associated Universities, Inc (US).


    National Radio Astronomy Observatory (US) Karl G Jansky Very Large Array located in central New Mexico on the Plains of San Agustin, between the towns of Magdalena and Datil, ~50 miles (80 km) west of Socorro. The VLA comprises twenty-eight 25-meter radio telescopes.

    ngVLA, to be located near the location of the NRAO Karl G. Jansky Very Large Array (US) site on the plains of San Agustin, fifty miles west of Socorro, NM, USA, at an elevation of 6970 ft (2124 m) with additional mid-baseline stations currently spread over greater New Mexico, Arizona, Texas, and Mexico.

    National Radio Astronomy Observatory (US)Very Long Baseline Array.

    European Southern Observatory [Observatoire européen austral][Europäische Südsternwarte] (EU)/National Radio Astronomy Observatory(US)/National Astronomical Observatory of Japan(JP) ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres.
    Access to ALMA observing time by the North American astronomical community will be through the North American ALMA Science Center (NAASC).

    *The Very Long Baseline Array (VLBA) comprises ten radio telescopes spanning 5,351 miles. It’s the world’s largest, sharpest, dedicated telescope array. With an eye this sharp, you could be in Los Angeles and clearly read a street sign in New York City!

    Astronomers use the continent-sized VLBA to zoom in on objects that shine brightly in radio waves, long-wavelength light that’s well below infrared on the spectrum. They observe blazars, quasars, black holes, and stars in every stage of the stellar life cycle. They plot pulsars, exoplanets, and masers, and track asteroids and planets.

     
  • richardmitnick 11:57 am on December 20, 2021 Permalink | Reply
    Tags: "ngVLA Project News", , , Call for proposals-the fifth ngVLA Community Studies Program, , Radio Astronomy,   

    From The National Radio Astronomy Observatory (US) : “ngVLA Project News” 

    NRAO Banner

    From The National Radio Astronomy Observatory (US)

    12.20.21
    Eric Murphy

    ngVLA Science Advisory Council Changes

    The next generation Very Large Array (ngVLA) [depicted below] Science Advisory Council (SAC) is the interface between the scientific community and the Project Office. Since the SAC’s formation in 2016, its members have provided invaluable guidance and feedback on many aspects of the ngVLA, helping shape it and underpin its strong endorsement from the Astro2020 Decadal Survey.

    With the Project now past this critical milestone, we have begun to reconstitute the SAC, starting with its leadership. It gives us great pleasure to announce that Brenda Matthews (The National Research Council of Canada [Conseil national de recherches Canada](CA)) and David Wilner (Center for Astrophysics | Harvard & Smithsonian) will serve as the new SAC Co-Chairs. They have been deeply engaged in the SAC and its Science Working Groups, and know the ngVLA well.

    We wish to thank the founding Co-Chairs of the SAC, Alberto Bolatto (University of Maryland) and Andrea Isella (Rice University). Their leadership was incredibly effective and a primary reason for the ngVLA's success with Astro2020. To ensure a smooth Co-Chair transition, Alberto and Andrea will serve as ex-officio members of the SAC's Executive Committee, a steering body. The full SAC membership will be announced in due course.
    ngVLA Community Studies Program Call for Proposals

    As the ngVLA Project heads towards the completion of its Conceptual Design and starts to begin work on the Preliminary Design, we are pleased to announce this call for proposals, the fifth ngVLA Community Studies Program. The proposal receipt deadline is 14 February 2022, 23:59 EST.

    Community Studies are designed to further develop the most pressing science questions that can be addressed by the ngVLA. As with previous rounds, we expect that all approved Community Studies will document their findings as part of a peer-reviewed journal article or ngVLA memo, and present their progress/final results at an appropriate science meeting, such as the January 2023 American Astronomical Society meeting. Consequently, we anticipate funding most formally approved proposals at a modest level to offset possible travel expenses, as well as for publication charges for papers expected to result from the study. We also expect to fund a small number of these Community Studies at a more significant level (up to $30,000 per award) through the ngVLA Community Studies Grants program.

    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 National Radio Astronomy Observatory (US) is a facility of The National Science Foundation (US), operated under cooperative agreement by The Associated Universities, Inc (US).


    National Radio Astronomy Observatory (US) Karl G Jansky Very Large Array located in central New Mexico on the Plains of San Agustin, between the towns of Magdalena and Datil, ~50 miles (80 km) west of Socorro. The VLA comprises twenty-eight 25-meter radio telescopes.

    ngVLA, to be located near the location of the NRAO Karl G. Jansky Very Large Array (US) site on the plains of San Agustin, fifty miles west of Socorro, NM, USA, at an elevation of 6970 ft (2124 m) with additional mid-baseline stations currently spread over greater New Mexico, Arizona, Texas, and Mexico.

    National Radio Astronomy Observatory (US)Very Long Baseline Array.

    European Southern Observatory [Observatoire européen austral][Europäische Südsternwarte] (EU)/National Radio Astronomy Observatory(US)/National Astronomical Observatory of Japan(JP) ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres.
    Access to ALMA observing time by the North American astronomical community will be through the North American ALMA Science Center (NAASC).

    *The Very Long Baseline Array (VLBA) comprises ten radio telescopes spanning 5,351 miles. It’s the world’s largest, sharpest, dedicated telescope array. With an eye this sharp, you could be in Los Angeles and clearly read a street sign in New York City!

    Astronomers use the continent-sized VLBA to zoom in on objects that shine brightly in radio waves, long-wavelength light that’s well below infrared on the spectrum. They observe blazars, quasars, black holes, and stars in every stage of the stellar life cycle. They plot pulsars, exoplanets, and masers, and track asteroids and planets.

     
  • richardmitnick 5:26 pm on December 19, 2021 Permalink | Reply
    Tags: "Closing in on the first light in the Universe", , , , , , , , Radio Astronomy, Research using new antennas in the Australian hinterland has reduced background noise and brought us closer to finding a 13-billion-year-old signal.,   

    From ARC Centres of Excellence for All Sky Astrophysics in 3D (AU) : “Closing in on the first light in the Universe” 

    arc-centers-of-excellence-bloc

    From ARC Centres of Excellence for All Sky Astrophysics in 3D (AU)

    15 December, 2021

    Tamzin Byrne
    tamzin@scienceinpublic.com.au
    +61 432 47 42 48

    Niall Byrne
    niall@scienceinpublic.com.au
    +61 417 131 977

    1
    Dr Christene Lynch at MWA.

    Research using new antennas in the Australian hinterland has reduced background noise and brought us closer to finding a 13-billion-year-old signal.

    The early Universe was dark, filled with a hot soup of opaque particles. These condensed to form neutral hydrogen which coalesced to form the first stars in what astronomers call the Epoch of Reionisation (EoR).

    “Finding the weak signal of this first light will help us understand how the early stars and galaxies formed,” says Dr Christene Lynch from ASTRO 3D, the ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions.

    Dr Lynch is first author on a paper published in Publications of the Astronomical Society of Australia. She and her colleagues from Curtin University (AU) and the International Centre for Radio Astronomy Research (AU) have reduced the background noise in their observations allowing them to home in on the elusive signal.

    The team worked with new equipment installed on the Murchison Widefield Array (MWA)[below], a radio telescope situated inland and some 800 kilometres north of Perth.

    The MWA started operation a decade ago. One of its aims is to find the radio wave signature of that first light, known as the Epoch of Reionisation, or “EoR.”

    Universe Atacama Large Millimiter/submillimeter Array (CL) [ALMA] Years After the Big Bang Credit: National Astronomical Observatory of Japan[国立天文台] (JP).

    It comprises multiple low-frequency “antenna tiles” which work together to search the sky for the faint remnant of the out-pouring of ionised hydrogen atoms that accompanied first light, which began around 500 million to one billion years after the Big Bang.

    Recently the number of antenna tiles was doubled from 128 to 256, significantly extending the land area occupied by the facility – and greatly upping its power.

    By combining some of the existing tiles with 56 of the new ones, ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions scientist Dr Christene Lynch and her team were able to run a new sky experiment, called the Long Baseline Epoch of Reionisation Survey (LoBES), to refine the hunt for the long-sought signal.

    “Our challenge is that the Universe is very, very crowded,” Dr Lynch explained.

    “There are too many other radio sources that are much brighter than the EoR signal lying between it and us. It is like trying to hear someone whispering from across the room, when between you and that person there are thousands of other people shouting as loudly as possible.

    “By using the new tiles and thus expanding the physical area over which the antenna work we were able to reduce a lot of that interference. As more and more of the tiles are added in, we’ll have a much better chance of finding the echo of that first light.”

    Dr Lynch worked with colleagues from ASTRO 3D and the Curtin University (AU) node of the International Centre for Radio Astronomy Research [ICRAR].

    They surveyed more than 80,000 radio signal sources, taking 16 spectral measurements for each. Running the results, they produced real and simulated models in which the noisiest foreground radio signals were reduced by a factor of three.

    “The Epoch of Reionisation signal started life as a hydrogen atom radio wavelength of 21 centimetres,” explained Dr Lynch.

    “Over the intervening billions of years it has been stretched and grown very, very faint. It’s clear that our new LoBES sky model will significantly improve efforts to properly locate it.”

    Co-author Professor Cathryn Trott, an ASTRO 3D Chief Investigator with ICRAR and Curtin, added: “This is our deepest and most detailed view to-date of the radio sky in these EoR fields, and this new catalogue provides us with a cleaner path to locating the EoR signal – a detection that will be a very major achievement for astronomy.”

    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 ARC Centre of Excellence in All Sky Astrophysics in 3 Dimensions (AU)

    Unifies over 200 world-leading astronomers to understand the evolution of the matter, light, and elements from the Big Bang to the present day.

    We are combining Australian innovative 3D optical and radio technology with new theoretical supercomputer simulations on a massive scale, requiring new big data techniques.

    Through our nationwide training and education programs, we are training young scientific leaders and inspiring high-school students into STEM sciences to prepare Australia for the next generation of telescopes: the Square Kilometre Array and the Extremely Large Optical telescopes.

    The objectives for the ARC Centres of Excellence (AU) are to to:

    Undertake highly innovative and potentially transformational research that aims to achieve international standing in the fields of research envisaged and leads to a significant advancement of capabilities and knowledge.

    Link existing Australian research strengths and build critical mass with new capacity for interdisciplinary, collaborative approaches to address the most challenging and significant research problems.

    Develop relationships and build new networks with major national and international centres and research programs to help strengthen research, achieve global competitiveness and gain recognition for Australian research

    Build Australia’s human capacity in a range of research areas by attracting and retaining, from within Australia and abroad, researchers of high international standing as well as the most promising research students.

    Provide high-quality postgraduate and postdoctoral training environments for the next generation of researchers.

    Offer Australian researchers opportunities to work on large-scale problems over long periods of time.

    Establish Centres that have an impact on the wider community through interaction with higher education institutes, governments, industry and the private and non-profit sector.

    SKA Murchison Widefield Array (AU), Boolardy station in outback Western Australia, at the Murchison Radio-astronomy Observatory (MRO), on the traditional lands of the Wajarri peoples.

    The Murchison Radio-astronomy Observatory,on the traditional lands of the Wajarri peoples, in outback Western Australia will house up to 130,000 antennas like these and the associated advanced technologies.

    EDGES telescope in a radio quiet zone at the Murchison Radio-astronomy Observatory in Western Australia, on the traditional lands of the Wajarri peoples.

    SKA ASKAP Pathfinder Radio Telescope.

     
  • richardmitnick 6:27 pm on December 18, 2021 Permalink | Reply
    Tags: , , , , Radio Astronomy, The Netherlands Institute for Radio Astronomy (ASTRON) (NL)   

    From The Netherlands Institute for Radio Astronomy (ASTRON) (NL) : “Most detailed-ever images of galaxies revealed using LOFAR” 

    ASTRON bloc

    From The Netherlands Institute for Radio Astronomy (ASTRON) (NL)

    17 August 2021

    After almost a decade of work, an international team of astronomers has published the most detailed images yet seen of galaxies beyond our own, revealing their inner workings in unprecedented detail. The images were created from data collected by the Low Frequency Array (LOFAR), a radio telescope built and maintained by ASTRON, LOFAR is a network of more than 70,000 small antennae spread across nine European counties, with its core in Exloo, the Netherlands. The results come from the team’s years of work, led by Dr Leah Morabito at Durham University. The team was supported by The STFC [Science & Technology Facilities Council] (UK).

    Revealing a hidden universe of light in HD

    The universe is awash with electromagnetic radiation, of which visible light comprises just the tiniest slice. From short-wavelength gamma rays and X-rays, to long-wavelength microwave and radio waves, each part of the light spectrum reveals something unique about the universe.

    The LOFAR network captures images at FM radio frequencies that, unlike shorter wavelength sources like visible light, are not blocked by the clouds of dust and gas that can cover astronomical objects. Regions of space that seem dark to our eyes, actually burn brightly in radio waves – allowing astronomers to peer into star-forming regions or into the heart of galaxies themselves.

    The new images, made possible because of the international nature of the collaboration, push the boundaries of what we know about galaxies and super-massive black holes. A special issue of the scientific journal Astronomy & Astrophysics is dedicated to 11 research papers describing these images and the scientific results.

    1
    A compilation of the science results. Credit from left to right starting at the top: N. Ramírez-Olivencia et el. [radio];The National Aeronautics and Space Agency(US), The European Space Agency [Agence spatiale européenne][Europäische Weltraumorganisation](EU), the Hubble Heritage Team (The Space Telescope Science Institute (US)/The Association of Universities for Research in Astronomy (AURA)(US))-ESA/Hubble Collaboration and A. Evans (The University of Virginia (US)/The National Radio Astronomy Observatory (US)/The University at Stony Brook-SUNY (US) ), edited by R. Cumming [optical], C. Groeneveld, R. Timmerman; LOFAR & Hubble Space Telescope,. Kukreti; LOFAR & The Sloan Digital Sky Survey (US), A. Kappes, F. Sweijen; LOFAR & DESI Legacy Imaging Survey, S. Badole; NASA, ESA & L. Calcada, Graphics: W.L. Williams.

    Better resolution by working together

    The images reveal the inner-workings of nearby and distant galaxies at a resolution 20 times sharper than typical LOFAR images. This was made possible by the unique way the team made use of the array.

    The 70,000+ LOFAR antennae are spread across Europe, with the majority being located in the Netherlands. In standard operation, only the signals from antennae located in the Netherlands are combined, and creates a ‘virtual’ telescope with a collecting ‘lens’ with a diameter of 120 km. By using the signals from all of the European antennae, the team have increased the diameter of the ‘lens’ to almost 2,000 km, which provides a twenty-fold increase in resolution.

    Unlike conventional array antennae that combine multiple signals in real time to produce images, LOFAR uses a new concept where the signals collected by each antenna are digitised, transported to central processor, and then combined to create an image. Each LOFAR image is the result of combining the signals from more than 70,000 antennae, which is what makes their extraordinary resolution possible.

    3
    This shows real radio galaxies from Morabito et al. (2021). The gif fades from the standard resolution to the high resolution, showing the detail we can see by using the new techniques. Credit: L.K. Morabito; LOFAR Surveys KSP.

    After almost a decade of work, an international team of astronomers has published the most detailed images yet seen of galaxies beyond our own, revealing their inner workings in unprecedented detail. The images were created from data collected by the Low Frequency Array (LOFAR), a radio telescope built and maintained by ASTRON, LOFAR is a network of more than 70,000 small antennae spread across nine European counties, with its core in Exloo, the Netherlands. The results come from the team’s years of work, led by Dr Leah Morabito at Durham University. The team was supported in the UK by the Science and Technology Facilities Council (STFC).

    As well as supporting science exploitation, STFC also funds the UK subscription to LOFAR including upgrade costs and operation of its LOFAR station in Hampshire.

    Published by the editorial team, 17 August 2021
    Revealing a hidden universe of light in HD

    The universe is awash with electromagnetic radiation, of which visible light comprises just the tiniest slice. From short-wavelength gamma rays and X-rays, to long-wavelength microwave and radio waves, each part of the light spectrum reveals something unique about the universe.

    The LOFAR network captures images at FM radio frequencies that, unlike shorter wavelength sources like visible light, are not blocked by the clouds of dust and gas that can cover astronomical objects. Regions of space that seem dark to our eyes, actually burn brightly in radio waves – allowing astronomers to peer into star-forming regions or into the heart of galaxies themselves.

    The new images, made possible because of the international nature of the collaboration, push the boundaries of what we know about galaxies and super-massive black holes. A special issue of the scientific journal Astronomy & Astrophysics is dedicated to 11 research papers describing these images and the scientific results.

    A compilation of the science results. Credit from left to right starting at the top: N. Ramírez-Olivencia et el. [radio]; NASA, ESA, the Hubble Heritage Team (STScI/AURA)-ESA/Hubble Collaboration and A. Evans (University of Virginia, Charlottesville/NRAO/Stony Brook University), edited by R. Cumming [optical], C. Groeneveld, R. Timmerman; LOFAR & Hubble Space Telescope,. Kukreti; LOFAR & Sloan Digital Sky Survey, A. Kappes, F. Sweijen; LOFAR & DESI Legacy Imaging Survey, S. Badole; NASA, ESA & L. Calcada, Graphics: W.L. Williams.
    Better resolution by working together

    The images reveal the inner-workings of nearby and distant galaxies at a resolution 20 times sharper than typical LOFAR images. This was made possible by the unique way the team made use of the array.

    The 70,000+ LOFAR antennae are spread across Europe, with the majority being located in the Netherlands. In standard operation, only the signals from antennae located in the Netherlands are combined, and creates a ‘virtual’ telescope with a collecting ‘lens’ with a diameter of 120 km. By using the signals from all of the European antennae, the team have increased the diameter of the ‘lens’ to almost 2,000 km, which provides a twenty-fold increase in resolution.

    Unlike conventional array antennae that combine multiple signals in real time to produce images, LOFAR uses a new concept where the signals collected by each antenna are digitised, transported to central processor, and then combined to create an image. Each LOFAR image is the result of combining the signals from more than 70,000 antennae, which is what makes their extraordinary resolution possible.

    This shows real radio galaxies from Morabito et al. (2021). The gif fades from the standard resolution to the high resolution, showing the detail we can see by using the new techniques. Credit: L.K. Morabito; LOFAR Surveys KSP.

    Revealing jets and outflows from super-massive black holes

    Super-massive black holes can be found lurking at the heart of many galaxies and many of these are ‘active’ black holes that devour in-falling matter and belch it back out into the cosmos as powerful jets and outflows of radiation. These jets are invisible to the naked eye, but they burn bright in radio waves and it is these that the new high-resolution images have focused upon.

    Dr Neal Jackson of The University of Manchester (UK), said: “These high resolution images allow us to zoom in to see what’s really going on when super-massive black holes launch radio jets, which wasn’t possible before at frequencies near the FM radio band,”

    The team’s work forms the basis of nine scientific studies that reveal new information on the inner structure of radio jets in a variety of different galaxies.

    3
    Hercules A is powered by a supermassive black hole located at its centre, which feeds on the surrounding gas and channels some of this gas into extremely fast jets. Our new high-resolutions observations taken with LOFAR have revealed that this jet grows stronger and weaker every few hundred thousand years. This variability produces the beautiful structures seen in the giant lobes, each of which is about as large as the Milky Way galaxy. Credit: R. Timmerman; LOFAR & Hubble Space Telescope.

    A decade-long challenge

    Even before LOFAR started operations in 2012, the European team of astronomers began working to address the colossal challenge of combining the signals from more than 70,000 antennae located as much as 2,000 km apart. The result, a publicly-available data-processing pipeline, which is described in detail in one the scientific papers, will allow astronomers from around the world to use LOFAR to make high-resolution images with relative ease.

    Dr Leah Morabito of Durham University (UK), said: “Our aim is that this allows the scientific community to use the whole European network of LOFAR telescopes for their own science, without having to spend years to become an expert.”

    Super images require supercomputers

    The relative ease of the experience for the end user belies the complexity of the computational challenge that makes each image possible. Because LOFAR doesn’t just ‘take pictures’ of the night sky, it must stitch together the data gathered by more than 70,000 antennae, which is a huge computational task. To produce a single image, more than 13 terabits of raw data per second – the equivalent of more than a three hundred DVDs – must be digitised, transported to a central processor and then combined.

    Frits Sweijen of The Leiden University [Universiteit Leiden](NL), said: “To process such immense data volumes we have to use supercomputers. These allow us to transform the terabytes of information from these antennas into just a few gigabytes of science-ready data, in only a couple of days.”

    All images and video’s belonging to this press release can be found in high resolution here.

    Links to Arxiv (free) papers can be found here. Or, here they are, with links:

    Sub-arcsecond imaging with the Low Frequency Array I. Foundational calibration strategy and
    pipeline
    ◦ Lead author: L. Morabito, Durham University
    https://arxiv.org/abs/2108.07283
    Sub-arcsecond imaging with the Low Frequency Array II. the Long Baseline Calibrator Survey
    ◦ Lead author: N. Jackson, University of Manchester
    https://arxiv.org/abs/2108.07284
    High-resolution international LOFAR observations of 4C 43.15: spectral ages and injection indices
    in a high-z radio galaxy
    ◦ Lead author: F. Sweijen, Leiden University
    https://arxiv.org/abs/2108.07290
    Subarcsecond LOFAR imaging of Arp299 at 150 MHz. Tracing the nuclear and diffuse extended
    emission of a bright LIRG
    ◦ Lead author: N. Ramírez-Olivencia, IAA-CSIC
    https://arxiv.org/abs/2108.07291
    Origin of the ring structures in Hercules A — sub-arcsecond 144 MHz to 7 GHz observations
    ◦ Lead author: R. Timmerman, Leiden University
    https://arxiv.org/abs/2108.07287
    Unmasking the history of 3C293 with LOFAR sub-arcsecond imaging
    ◦ Lead author: P. Kukreti, University of Groningen
    https://arxiv.org/abs/2108.07289
    High-resolution imaging with the Low-Frequency Array:international baseline observations of the
    gravitational lenses MG 0751+2716 and CLASS B1600+434
    ◦ Lead author: S. Badole, University of Manchester
    https://arxiv.org/abs/2108.07293
    The resolved jet of 3C 273 at 150 MHz: Sub-arcsecond imaging with the LOFAR international
    baselines
    ◦ Lead author: J. Harwood, University of Hertfordshire
    https://arxiv.org/abs/2108.07288
    Sub-arcsecond imaging of 3C sources at 50 MHz with LOFAR-VLBI
    ◦ Lead author: C. Groeneveld, Leiden University
    https://arxiv.org/abs/2108.07286
    Spectral analysis of spatially-resolved 3C295 (sub-acsec resolution) using LOFAR-VLBI &
    archival eMERLIN+VLA data.
    ◦ Lead author: E. Bonnassieux, INAF
    https://arxiv.org/abs/2108.07294


    In this video by Dr Becky Smethurst she explains what LOFAR is and what is so significant to this press release. She also interviews Leah Morabito, Shruti Baldoe and Frits Sweijen.
    27 minutes.


    The full interview with Dr Leah Morabito by Dr Becky Smethurst.
    15 minutes.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    ASTRON is the ASTRON- The Netherlands Institute for Radio Astronomy [Nederlands Instituut voor Radioastronomie] (NL). Its main office is in Dwingeloo in the Dwingelderveld National Park in the province of Drenthe. ASTRON is part of Netherlands Organisation for Scientific Research (NWO).

    ASTRON’s main mission is to make discoveries in radio astronomy happen, via the development of new and innovative technologies, the operation of world-class radio astronomy facilities, and the pursuit of fundamental astronomical research. Engineers and astronomers at ASTRON have an outstanding international reputation for novel technology development, and fundamental research in galactic and extra-galactic astronomy. Its main funding comes from NWO.

    ASTRON’s programme has three principal elements:

    The operation of front line observing facilities, including especially the Westerbork Synthesis Radio Telescope and LOFAR,
    The pursuit of fundamental astronomical research using ASTRON facilities, together with a broad range of other telescopes around the world and space-borne instruments (e.g. Sptizer, HST etc.)
    A strong technology development programme, encompassing both innovative instrumentation for existing telescopes and the new technologies needed for future facilities.

    In addition, ASTRON is active in the international science policy arena and is one of the leaders in the international SKA project. The Square Kilometre Array will be the world’s largest and most sensitive radio telescope with a total collecting area of approximately one square kilometre. The SKA will be built in Southern Africa and in Australia. It is a global enterprise bringing together 11 countries from the 5 continents.

    Radio telescopes

    ASTRON operates the Westerbork Synthesis Radio Telescope (WSRT), one of the largest radio telescopes in the world. The WSRT and the International LOFAR Telescope (ILT) are dedicated to explore the universe at radio frequencies ranging from 10 MHz to 8 GHz.

    Westerbork Synthesis Radio Telescope, an aperture synthesis interferometer near World War II Nazi detention and transit camp Westerbork, north of the village of Westerbork, Midden-Drenthe, in the northeastern Netherlands.

    In addition to its use as a stand-alone radio telescope, the Westerbork array participates in the European Very Long Baseline Interferometry Network (EVN) of radio telescopes.

    ASTRON is the host institute for the Joint Institute for VLBI in Europe (JIVE).

    European Very Long Baseline Interferometry Network

    Its primary task is to operate the EVN MkIV VLBI Data Processor (correlator). JIVE also provides a high-level of support to astronomers and the Telescope Network. ASTRON also hosts the NOVA Optical/ Infrared instrumentation group.

    LOFAR is a radio telescope composed of an international network of antenna stations and is designed to observe the universe at frequencies between 10 and 250 MHz. Operated by ASTRON (NL), the network includes stations in the Netherlands, Germany, Sweden, the U.K., France, Poland and Ireland.

    ASTRON Institute for Radio Astronomy (NL) LOFAR Radio Antenna Bank(NL)

     
c
Compose new post
j
Next post/Next comment
k
Previous post/Previous comment
r
Reply
e
Edit
o
Show/Hide comments
t
Go to top
l
Go to login
h
Show/Hide help
shift + esc
Cancel
%d bloggers like this: