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  • richardmitnick 4:52 pm on January 5, 2022 Permalink | Reply
    Tags: "Scientists discover leftovers of Earth’s dramatic formation", , , , , The Australian National University (AU), The chemicals; rocks and layers that make up ULVZs have largely been sitting unchanged for billions of years and the early days of the planet's formation.,   

    From The Australian National University (AU) : “Scientists discover leftovers of Earth’s dramatic formation” 

    ANU Australian National University Bloc

    From The Australian National University (AU)

    1
    Researchers have uncovered the most detail ever of the mysterious structures laying between the Earth’s mantle and core, also providing the strongest evidence yet they started life as an ocean of molten magma that eventually sunk.

    A team of international researchers, including scientists from The Australian National University (ANU), used thousands of computer-modelled seismic waves to examine Ultra-Low Velocity Zones (ULVZs) beneath the Coral Sea between Australia and New Zealand. The area was selected because of the high frequency of earthquakes and the seismic waves these events unleash.

    ULVZs sit at the bottom of the planet’s mantle and on top of its liquid metal outer core, and are so thin that they are normally invisible to tomographic imaging. For decades, scientists have speculated they are leftovers of the violent processes that shaped the early Earth.

    Study co-author, Professor Hrvoje Tkalčić from ANU, said the team’s findings confirm the chemicals, rocks and layers that make up ULVZs have largely been sitting unchanged for billions of years and the early days of the planet’s formation.

    “For a long time no-one really knew for sure what these mysterious ULVZs were made up of. Now, we’ve developed the clearest picture yet. Using advances in seismology and mathematical geophysics made at ANU we’ve shown that ULVZs are made up of layers,” Professor Tkalčić said.

    “Over billions years of the Earth’s shaping and reshaping, these zones have churned close to the planet’s core but largely remained intact.

    “It’s like an egg in a cake that doesn’t get mixed in with the rest of the ingredients but stays as yoke and egg white, despite the constant mixing all around it.

    “This is a really significant breakthrough as we have unlocked not only a clue as to how the early Earth formed but confirmed ULVZs are clumps of leftovers from this process that are pretty much the same as they were billions of years ago.”

    The study, published in Nature Geoscience, was led by Dr Surya Pachhai from The University of Utah (US), with much of the research completed as part of his PhD at ANU.

    According to Dr Pachhai the most surprising finding in the study is that ULVZs are made up of a lot more diverse materials than first thought.

    “ULVZs are not homogenous but contain strong structural and compositional variations within them,” he said.

    “We found that this type of ULVZs can be explained by chemical heterogeneities created at the very beginning of the Earth’s history and that they are still not well mixed after 4.5 billion years of mantle convection.”

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    ANU Campus

    The Australian National University (AU) is a world-leading university in Australia’s capital city, Canberra. Our location points to our unique history, ties to the Australian Government and special standing as a resource for the Australian people.

    Our focus on research as an asset, and an approach to education, ensures our graduates are in demand the world-over for their abilities to understand, and apply vision and creativity to addressing complex contemporary challenges.

    Australian National University is regarded as one of the world’s leading research universities, and is ranked as the number one university in Australia and the Southern Hemisphere by the 2021 QS World University Rankings. It is ranked 31st in the world by the 2021 QS World University Rankings, and 59th in the world (third in Australia) by the 2021 Times Higher Education.

    In the 2020 Times Higher Education Global Employability University Ranking, an annual ranking of university graduates’ employability, Australian National University was ranked 15th in the world (first in Australia). According to the 2020 QS World University by Subject, the university was also ranked among the top 10 in the world for Anthropology, Earth and Marine Sciences, Geography, Geology, Philosophy, Politics, and Sociology.

    Established in 1946, Australian National University is the only university to have been created by the Parliament of Australia. It traces its origins to Canberra University College, which was established in 1929 and was integrated into Australian National University in 1960. Australian National University enrolls 10,052 undergraduate and 10,840 postgraduate students and employs 3,753 staff. The university’s endowment stood at A$1.8 billion as of 2018.

    Australian National University counts six Nobel laureates and 49 Rhodes scholars among its faculty and alumni. The university has educated two prime ministers, 30 current Australian ambassadors and more than a dozen current heads of government departments of Australia. The latest releases of ANU’s scholarly publications are held through ANU Press online.

     
  • richardmitnick 11:01 pm on November 30, 2021 Permalink | Reply
    Tags: "Mysterious clouds could offer new clues on dark matter", Boson clouds-made up of ultralight subatomic particles that are almost impossible to detect-have been suggested as a possible source of Dark Matter., Gravitational wave science has opened doors that were previously locked to scientists., The Australian National University (AU), The hunt for gravitational waves could help solve one of the Universe's other burning mysteries - boson clouds and whether they are a leading contender for dark matter.   

    From The Australian National University (AU) : “Mysterious clouds could offer new clues on dark matter” 

    ANU Australian National University Bloc

    From The Australian National University (AU)

    1 December 2021
    James Giggacher
    +61 2 6125 7979
    media@anu.edu.au

    1
    Dr. Lilli Sun is on the hunt for boson clouds. Photo Tracey Nearmy/ ANU.

    The hunt for gravitational waves, ripples in space and time caused by major cosmic cataclysms, could help solve one of the Universe’s other burning mysteries – boson clouds and whether they are a leading contender for dark matter.

    Researchers are using powerful instruments, like the advanced Laser Interferometer Gravitational-Wave Observatory (LIGO), advanced Virgo, and KAGRA, that detect gravitational waves up to billions of light years away to locate potential boson clouds.
    _____________________________________________________________________________________
    LIGOVIRGOKAGRA

    Caltech /MIT Advanced aLigo

    Caltech/MIT Advanced aLigo detector installation Livingston, LA, USA.

    Caltech/MIT Advanced aLigo Hanford, WA, USA installation.

    VIRGO Gravitational Wave interferometer, near Pisa, Italy

    KAGRA Large-scale Cryogenic Gravitational Wave Telescope Project (JP)
    _____________________________________________________________________________________

    LIGO Virgo Kagra Masses in the Stellar Graveyard. Credit: Frank Elavsky and Aaron Geller at Northwestern University(US)

    Boson clouds-made up of ultralight subatomic particles that are almost impossible to detect-have been suggested as a possible source of Dark Matter – which accounts for about 85 per cent of all matter in the Universe.

    Now a major new international study [see science paper below] carried out in the LIGO-Virgo-KAGRA collaboration and co-led by researchers from The Australian National University (ANU), offers one of the best leads yet to hunt down these subatomic particles by searching for gravitational waves caused by boson clouds circling black holes.

    Dr Lilli Sun, from the ANU Centre for Gravitational Astrophysics, said the study was the first all-sky survey in the world tailored to look for predicted gravitational waves coming from possible boson clouds near rapidly spinning black holes.

    “It is almost impossible to detect these ultralight boson particles on Earth,” Dr Sun said.

    “The particles, if they exist, have extremely small mass and rarely interact with other matter — which is one of the key properties that dark matter seems to have. Dark matter is material that cannot be seen directly, but we know that dark matter exists because of the effect it has on objects that we can observe.

    “But by searching for gravitational waves emitted by these clouds we may be able to track down these elusive boson particles and possibly crack the code of dark matter. Our searches could also allow to rule out certain ultralight boson particles that our theories say could exist but actually don’t.”

    Dr Sun, also an Associate Investigator at the ARC Centre of Excellence for Gravitational Wave Discovery (OzGrav), said gravitational wave detectors allowed researchers to examine the energy of rapidly rotating black holes extracted by such clouds if they exist.

    “We believe these black holes trap a huge number of boson particles in their powerful gravity field, creating a cloud corotating with them. This delicate dance continues for millions of years and keeps generating gravitational waves that hurtle through space,” she said.

    While the researchers haven’t yet detected gravitational waves from boson clouds, Dr Sun said gravitational wave science had “opened doors that were previously locked to scientists”.

    “Gravitational-wave discoveries not only provide information about mysterious compact objects in the Universe, like black holes and neutron stars, they also allow us to look for new particles and dark matter,” she said.

    “Future gravitational wave detectors will certainly open more possibilities. We will be able to reach deeper into the Universe and discover more insights about these particles.

    “For example, the discovery of boson clouds using gravitational wave detectors would bring important insights about dark matter and help advance other searches for dark matter. It would also advance our understanding of particle physics more broadly.”

    In another significant breakthrough, the study also shed more light on the chance of boson clouds existing in our own galaxy by taking into consideration their ages.

    Dr Sun said the strength of any gravitational wave depends on the age of the cloud, with older ones sending out weaker signals.

    “The boson cloud shrinks as it loses energy by sending out gravitational waves,” Dr Sun said.

    “We learnt that a particular type of boson cloud younger than 1,000 years is not likely to exist anywhere in our galaxy, while clouds that are up to 10 million years old are not likely to exist within about 3,260 light years from Earth.”

    Science paper:
    All-sky search for gravitational wave emission from scalar boson clouds aroundspinning black holes in LIGO O3 data

    ______________________________________________________
    Dark Matter Background
    Fritz Zwicky discovered Dark Matter in the 1930s when observing the movement of the Coma Cluster., Vera Rubin a Woman in STEM, denied the Nobel, some 30 years later, did most of the work on Dark Matter.

    Fritz Zwicky.
    Coma cluster via NASA/ESA Hubble, the original example of Dark Matter discovered during observations by Fritz Zwicky and confirmed 30 years later by Vera Rubin.
    In modern times, it was astronomer Fritz Zwicky, in the 1930s, who made the first observations of what we now call dark matter. His 1933 observations of the Coma Cluster of galaxies seemed to indicated it has a mass 500 times more than that previously calculated by Edwin Hubble. Furthermore, this extra mass seemed to be completely invisible. Although Zwicky’s observations were initially met with much skepticism, they were later confirmed by other groups of astronomers.

    Thirty years later, astronomer Vera Rubin provided a huge piece of evidence for the existence of dark matter. She discovered that the centers of galaxies rotate at the same speed as their extremities, whereas, of course, they should rotate faster. Think of a vinyl LP on a record deck: its center rotates faster than its edge. That’s what logic dictates we should see in galaxies too. But we do not. The only way to explain this is if the whole galaxy is only the center of some much larger structure, as if it is only the label on the LP so to speak, causing the galaxy to have a consistent rotation speed from center to edge.

    Vera Rubin, following Zwicky, postulated that the missing structure in galaxies is dark matter. Her ideas were met with much resistance from the astronomical community, but her observations have been confirmed and are seen today as pivotal proof of the existence of dark matter.
    Astronomer Vera Rubin at the Lowell Observatory in 1965, worked on Dark Matter (The Carnegie Institution for Science).

    Vera Rubin measuring spectra at the Department of Terrestrial Magnetism at the Carnegie Institution in Washington in about 1970. (Emilio Segre Visual Archives AIP SPL).

    Vera Rubin, with Department of Terrestrial Magnetism (DTM) image tube spectrograph attached to the Kitt Peak 84-inch telescope, 1970.

    Dark Matter Research

    LBNL LZ Dark Matter Experiment (US) xenon detector at Sanford Underground Research Facility(US) Credit: Matt Kapust.

    Lamda Cold Dark Matter Accerated Expansion of The universe http scinotions.com the-cosmic-inflation-suggests-the-existence-of-parallel-universes. Credit: Alex Mittelmann.

    DAMA at Gran Sasso uses sodium iodide housed in copper to hunt for dark matter LNGS-INFN.

    Yale HAYSTAC axion dark matter experiment at Yale’s Wright Lab.

    DEAP Dark Matter detector, The DEAP-3600, suspended in the SNOLAB (CA) deep in Sudbury’s Creighton Mine

    The LBNL LZ Dark Matter Experiment (US) Dark Matter project at SURF, Lead, SD, USA.

    DAMA-LIBRA Dark Matter experiment at the Italian National Institute for Nuclear Physics’ (INFN’s) Gran Sasso National Laboratories (LNGS) located in the Abruzzo region of central Italy.

    DARWIN Dark Matter experiment. A design study for a next-generation, multi-ton dark matter detector in Europe at the University of Zurich.

    PandaX II Dark Matter experiment at Jin-ping Underground Laboratory (CJPL) in Sichuan, China.

    Inside the Axion Dark Matter eXperiment U Washington (US) Credit : Mark Stone U. of Washington. Axion Dark Matter Experiment.
    ______________________________________________________

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    ANU Campus

    The Australian National University (AU) is a world-leading university in Australia’s capital city, Canberra. Our location points to our unique history, ties to the Australian Government and special standing as a resource for the Australian people.

    Our focus on research as an asset, and an approach to education, ensures our graduates are in demand the world-over for their abilities to understand, and apply vision and creativity to addressing complex contemporary challenges.

    Australian National University is regarded as one of the world’s leading research universities, and is ranked as the number one university in Australia and the Southern Hemisphere by the 2021 QS World University Rankings. It is ranked 31st in the world by the 2021 QS World University Rankings, and 59th in the world (third in Australia) by the 2021 Times Higher Education.

    In the 2020 Times Higher Education Global Employability University Ranking, an annual ranking of university graduates’ employability, Australian National University was ranked 15th in the world (first in Australia). According to the 2020 QS World University by Subject, the university was also ranked among the top 10 in the world for Anthropology, Earth and Marine Sciences, Geography, Geology, Philosophy, Politics, and Sociology.

    Established in 1946, Australian National University is the only university to have been created by the Parliament of Australia. It traces its origins to Canberra University College, which was established in 1929 and was integrated into Australian National University in 1960. Australian National University enrolls 10,052 undergraduate and 10,840 postgraduate students and employs 3,753 staff. The university’s endowment stood at A$1.8 billion as of 2018.

    Australian National University counts six Nobel laureates and 49 Rhodes scholars among its faculty and alumni. The university has educated two prime ministers, 30 current Australian ambassadors and more than a dozen current heads of government departments of Australia. The latest releases of ANU’s scholarly publications are held through ANU Press online.

     
  • richardmitnick 11:01 am on November 8, 2021 Permalink | Reply
    Tags: "Scientists detect a "tsunami" of gravitational waves", , , , OzGrav-ARC CENTRE OF EXCELLENCE FOR GRAVITATIONAL WAVE DISCOVERY (AU), The Australian National University (AU),   

    From The Australian National University (AU) : “Scientists detect a “tsunami” of gravitational waves” 

    ANU Australian National University Bloc

    From The Australian National University (AU)

    8 November 2021
    James Giggacher
    +61 2 6125 7979
    media@anu.edu.au

    1
    Black Holes to merge. Credit: The National Aeronautics and Space Agency (US).
    Artist’s by now iconic conception of two merging black holes similar to those detected by LIGO. Credit: Aurore Simonnet /Caltech MIT Advanced aLIGO(US)/Sonoma State University (US).

    3
    Graphic by Carl Knox, OzGrav-ARC CENTRE OF EXCELLENCE FOR GRAVITATIONAL WAVE DISCOVERY (AU)The Swinburne University of Technology (AU), 90 detections!

    A team of international scientists, including researchers from The Australian National University (ANU), and researchers from the ARC Centre of Excellence for Gravitational Wave Discovery (OzGrav) have unveiled the largest number of gravitational waves ever detected.

    The discoveries will help solve some of the most complex mysteries of the Universe, including the building blocks of matter and the workings of space and time.

    The global team’s study, published today on Physical Review X, made 35 new detections of gravitational waves caused by pairs of black holes merging or neutron stars and black holes smashing together, using the LIGO and Virgo observatories between November 2019 and March 2020.

    _____________________________________________________________________________________
    LIGOVIRGOKAGRA

    Caltech /MIT Advanced aLigo

    Caltech/MIT Advanced aLigo detector installation Livingston, LA, USA.

    Caltech/MIT Advanced aLigo Hanford, WA, USA installation.

    VIRGO Gravitational Wave interferometer, near Pisa, Italy

    KAGRA Large-scale Cryogenic Gravitational Wave Telescope Project (JP)
    _____________________________________________________________________________________

    LIGO Virgo Kagra Masses in the Stellar Graveyard. Credit: Frank Elavsky and Aaron Geller at Northwestern University(US)

    This brings the total number of detections to 90 after three observing runs between 2015 and 2020.

    The new detections are from massive cosmic events, most of them billions of light years away, which hurl ripples through space-time. They include 32 black hole pairs merging, and likely three collisions between neutron stars and black holes.

    ANU is one of the key players in the international team making the observations and developing the sophisticated technology to hunt down elusive gravitational waves across the vast expanse of the Universe.

    Distinguished Professor Susan Scott, from the ANU Centre for Gravitational Astrophysics, said the latest discoveries represented “a tsunami” and were a “major leap forward in our quest to unlock the secrets of the Universe’s evolution”.

    “These discoveries represent a tenfold increase in the number of gravitational waves detected by LIGO and Virgo since they started observing,” Distinguished Professor Scott said.

    “We’ve detected 35 events. That’s massive! In contrast, we made three detections in our first observing run, which lasted four months in 2015-16.

    “This really is a new era for gravitational wave detections and the growing population of discoveries is revealing so much information about the life and death of stars throughout the Universe.

    “Looking at the masses and spins of the black holes in these binary systems indicates how these systems got together in the first place.

    “It also raises some really fascinating questions. For example, did the system originally form with two stars that went through their life cycles together and eventually became black holes? Or were the two black holes thrust together in a very dense dynamical environment such as at the centre of a galaxy?”

    Distinguished Professor Scott, who is also a Chief Investigator of the ARC Centre of Excellence for Gravitational Wave Discovery (OzGrav), said the continual improvement of gravitational wave detector sensitivity was helping drive an increase in detections.

    “This new technology is allowing us to observe more gravitational waves than ever before,” she said.

    “We are also probing the two black hole mass gap regions and providing more tests of Einstein’s theory of general relativity.

    “The other really exciting thing about the constant improvement of the sensitivity of the gravitational wave detectors is that this will then bring into play a whole new range of sources of gravitational waves, some of which will be unexpected.”

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    ANU Campus

    The Australian National University (AU) is a world-leading university in Australia’s capital city, Canberra. Our location points to our unique history, ties to the Australian Government and special standing as a resource for the Australian people.

    Our focus on research as an asset, and an approach to education, ensures our graduates are in demand the world-over for their abilities to understand, and apply vision and creativity to addressing complex contemporary challenges.

    Australian National University is regarded as one of the world’s leading research universities, and is ranked as the number one university in Australia and the Southern Hemisphere by the 2021 QS World University Rankings. It is ranked 31st in the world by the 2021 QS World University Rankings, and 59th in the world (third in Australia) by the 2021 Times Higher Education.

    In the 2020 Times Higher Education Global Employability University Ranking, an annual ranking of university graduates’ employability, Australian National University was ranked 15th in the world (first in Australia). According to the 2020 QS World University by Subject, the university was also ranked among the top 10 in the world for Anthropology, Earth and Marine Sciences, Geography, Geology, Philosophy, Politics, and Sociology.

    Established in 1946, Australian National University is the only university to have been created by the Parliament of Australia. It traces its origins to Canberra University College, which was established in 1929 and was integrated into Australian National University in 1960. Australian National University enrolls 10,052 undergraduate and 10,840 postgraduate students and employs 3,753 staff. The university’s endowment stood at A$1.8 billion as of 2018.

    Australian National University counts six Nobel laureates and 49 Rhodes scholars among its faculty and alumni. The university has educated two prime ministers, 30 current Australian ambassadors and more than a dozen current heads of government departments of Australia. The latest releases of ANU’s scholarly publications are held through ANU Press online.

     
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