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  • richardmitnick 12:57 pm on April 28, 2020 Permalink | Reply
    Tags: A new technique to reduce quantum noise in detectors., , , NAOJ, TAMA300 gravitational wave detector in Mitaka Tokyo   

    From National Astronomical Observatory of Japan: “TAMA300 Blazes Trail for Improved Gravitational Wave Astronomy” 

    Figure: Vacuum chambers in the infrastructure of the former TAMA300 detector used in this experiment. (Credit: NAOJ)

    From National Astronomical Observatory of Japan

    April 28, 2020

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    Figure: Vacuum chambers in the infrastructure of the former TAMA300 detector used in this experiment. (Credit: NAOJ)

    Researchers at the National Astronomical Observatory of Japan (NAOJ) have used the infrastructure of the former TAMA300 gravitational wave detector in Mitaka, Tokyo to demonstrate a new technique to reduce quantum noise in detectors. This new technique will help increase the sensitivity of the detectors comprising a collaborative worldwide gravitational wave network, allowing them to observe fainter waves.

    When it began observations in 2000, TAMA300 was one of the world’s first large-scale interferometric gravitational wave detectors. At that time TAMA300 had the highest sensitivity in the world, setting an upper limit on the strength of gravitational wave signals; but the first detection of actual gravitational waves was made 15 years later in 2015 by LIGO. Since then detector technology has improved to the point that modern detectors are observing several signals per month. The scientific results obtained from these observations are already impressive and many more are expected in the next decades. TAMA300 is no longer participating in observations, but is still active, acting as a testbed for new technologies to improve other detectors.

    The sensitivity of current and future gravitational wave detectors is limited at almost all the frequencies by quantum noise caused by the effects of vacuum fluctuations of the electromagnetic fields. But even this inherent quantum noise can be sidestepped. It is possible to manipulate the vacuum fluctuations to redistribute the quantum uncertainties, deceasing one type of noise at the expense of increasing a different, less obstructive type of noise. This technique, known as vacuum squeezing, has already been implemented in gravitational wave detectors, greatly increasing their sensitivity to higher frequency gravitational waves. But the optomechanical interaction between the electromagnetic field and the mirrors of the detector cause the effects of vacuum squeezing to change depending on the frequency. So at low frequencies vacuum squeezing increases the wrong type of noise, actually degrading sensitivity.

    To overcome this limitation and achieve reduced noise at all frequencies, a team at NAOJ composed of members of the in-house Gravitational Wave Science Project and the KAGRA collaboration (but also including researchers of the Virgo and GEO collaborations) has recently demonstrated the feasibility of a technique known as frequency dependent vacuum squeezing, at the frequencies useful for gravitational wave detectors. Because the detector itself interacts with the electromagnetic fields differently depending on the frequency, the team used the infrastructure of the former TAMA300 detector to create a field which itself varies depending on frequency. A normal (frequency independent) squeezed vacuum field is reflected off an optical cavity 300-m long, such that a frequency dependence is imprinted and it is able counteract the optomechanical effect of the interferometer.

    This technique will allow improved sensitivity at both high and low frequencies simultaneously. This is a crucial result demonstrating a key-technology to improve the sensitivity of future detectors. Its implementation, planned as a near term upgrade together with other improvements, is expected to double the observation range of second-generation detectors.

    These results will appear as Zhao, Y., et al. “Frequency-dependent squeezed vacuum source for broadband quantum noise reduction in advanced gravitational-wave detectors” in Physical Review Letters on April 28, 2020. A similar result has been obtained by a group in MIT using a 16-m filter cavity, and the two papers will be published jointly.

    See the full article here .

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    NAOJ

    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

    NAOJ/Subaru Telescope at Mauna Kea Hawaii, USA,4,207 m (13,802 ft) above sea level


    ESO/NRAO/NAOJ ALMA Array
    ESO/NRAO/NAOJ ALMA Array
    sft
    Solar Flare Telescope

    Nobeyama Millimeter Array Radioheliograph, located near Minamimaki, Nagano at an elevation of 1350m

    Mizusawa VERA Observatory

    Okayama Astrophysical Observatory

     
  • richardmitnick 4:10 pm on February 14, 2020 Permalink | Reply
    Tags: , , , , , , NAOJ,   

    From ALMA:”Galactic Cosmic Rays Affect Titan’s Atmosphere” 

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres

    From ALMA

    2020.02.14

    Planetary scientists using the Atacama Large Millimeter/submillimeter Array (ALMA) revealed the secrets of the atmosphere of Titan, the largest moon of Saturn. The team found a chemical footprint in Titan’s atmosphere indicating that cosmic rays coming from outside the Solar System affect the chemical reactions involved in the formation of nitrogen-bearing organic molecules. This is the first observational confirmation of such processes, and impacts the understanding of the intriguing environment of Titan.

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    Optical image of Titan taken by NASA Cassini spacecraft. Credit: NASA/JPL-Caltech/Space Science Institute

    NASA/ESA/ASI Cassini-Huygens Spacecraft

    Titan is attracting much interest because of its unique atmosphere with a number of organic molecules that form a pre-biotic environment.

    Takahiro Iino, a scientist at the University of Tokyo, and his team used ALMA to reveal the chemical processes in Titan’s atmosphere. They found faint but firm signals of acetonitrile (CH3CN) and its rare isotopomer CH3C^15N in the ALMA data.

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    ALMA spectra of CH3CN and CH3C^15N Titan’s atmosphere. Dotted vertical lines indicate the frequency of emission lines of two molecules predicted by a theoretical model.
    Credit: Iino et al. (The University of Tokyo)

    “We found that the abundance of 14N in acetonitrile is higher than those in other nitrogen bearing species such as HCN and HC3N,” says Iino. “It well matches the recent computer simulation of chemical processes with high energy cosmic rays.”

    There are two important players in the chemical processes of the atmosphere;
    ultraviolet (UV) light from the Sun and cosmic rays coming from outside the Solar System. In the upper atmosphere, UV light selectively destroys nitrogen molecules containing 15N because the UV light with the specific wavelength that interacts with 14N14N is easily absorbed at that altitude. Thus, nitrogen-bearing species produced at that altitude tend to exhibit a high 15N abundance. On the other hand, cosmic rays penetrate deeper and interact with nitrogen molecules containing 14N. As a result, there is a difference in the abundance of molecules with 14N and 15N. The team revealed that acetonitrile in the stratosphere is more abundant in 14N than those of other previously measured nitrogen-bearing molecules.

    “We suppose that galactic cosmic rays play an important role in the atmospheres of other solar system bodies,” says Hideo Sagawa, an associate professor at Kyoto Sangyo University and a member of the research team. “The process could be universal, so understanding the role of cosmic rays in Titan is crucial in overall planetary science.”

    Titan is one of the most popular objects in ALMA observations. The data obtained with ALMA needs to be calibrated to remove fluctuations due to variations of on-site weather and mechanical glitches. For referencing, the observatory staff often points the telescope at bright sources, such as Titan, from time to time in science observations. Therefore, a large amount of Titan data is stored in the ALMA Science Archive. Iino and his team have dug into the archive and re-analyzed the Titan data and found subtle fingerprints of very tiny amounts of CH3C15N.

    Paper and the research team
    These observation results are published as T. Iino et al. “14N/15N isotopic ratio in CH3CN of Titan’s atmosphere measured with ALMA” in The Astrophysical Journal published on February 2019.

    The research team members are:
    Takahiro Iino (The University of Tokyo), Hideo Sagawa (Kyoto Sangyo University) and Takashi Tsukagoshi (National Astronomical Observatory of Japan).

    This research was supported by the JSPS KAKENHI (No. 17K14420 and 19K14782), the Telecommunication Advancement Foundation, and the Astrobiology Center, National Institutes of Natural Sciences.

    See the full article here .

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    The Atacama Large Millimeter/submillimeter Array (ALMA), 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

     
  • richardmitnick 4:20 pm on February 5, 2020 Permalink | Reply
    Tags: Artificial Intelligence tool developed to predict the structure of the Universe, , NAOJ, The Kavli Institute for the Physics and Mathematics of the Universe - Tokyo, Yukawa Institute for Theoretical Physics   

    From The Kavli Institute for the Physics and Mathematics of the Universe – Tokyo: “Artificial Intelligence tool developed to predict the structure of the Universe” 

    KavliFoundation

    From The Kavli Institute for the Physics and Mathematics of the Universe – Tokyo

    Kavli IPMU
    From Kavli IMPU

    Artificial Intelligence tool developed to predict the structure of the Universe

    February 5, 2020
    Research contact
    Masahiro Takada
    Principal Investigator
    Kavli Institute for the Physics and Mathematics of the Universe
    University of Tokyo
    E-mail: masahiro.takada@ipmu.jp

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    Image 1: The way in which galaxies cluster together in the Universe is made clear in this image of the Universe as observed by the Sloan Digital Sky Survey (SDSS).

    SDSS Telescope at Apache Point Observatory, near Sunspot NM, USA, Altitude2,788 meters (9,147 ft)


    The yellow dots represent the position of individual galaxies, while the orange loop shows the area of the Universe spanning 1 billion light-years. At the center is Earth, and around it is a three-dimensional map of where different galaxies are. The image reveals how galaxies are not uniformly spread out throughout the Universe, and how they cluster together to create areas called filaments, or are completely absent in areas called voids. (Credit: Tsunehiko Kato, ARC and SDSS, NAOJ Four-Dimensional Digital Universe Project)

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    Image 2: The conceptual design of Dark Emulator. Left: an example of the virtual Universe created by “ATERUI II” supercomputer.

    NAOJ ATERUI II Cray XC50 supercomputer located at the National Astronomical Observatory in Japan (NAOJ)


    It shows the distribution of about 10 billion particles in a volume encompassing about 4.9 billion light years evolved until today. It takes about 2 days using 800 CPU cores in “ATERUI II”. Center: The architecture of Dark Emulator. It learns the correspondence between the fundamental cosmological parameters employed at the beginning of a simulation and its outcome based on a machine-learning architecture with hybrid implementation of multiple statistical methods. After training, the machine now immediately predicts accurately the expected observational signals for a new set of cosmological parameters without running a new simulation. This allows us to drastically reduce the computational cost needed for the extraction of cosmological parameters from observational data. (Credit: YITP, NAOJ)

    3
    An example of the virtual Universe created by “ATERUI II” supercomputer. It shows the distribution of about 10 billion particles in a volume encompassing about 4.9 billion light years evolved until today. It takes about 2 days using 800 CPU cores in “ATERUI II”. (Credit: YITP) From NAOJ

    The origin of how the Universe created its voids and filaments can now be studied within seconds after researchers developed an artificial intelligence tool called Dark Emulator.

    Advancements in telescopes have enabled researchers to study the Universe with greater detail, and to establish a standard cosmological model that explains various observational facts simultaneously. But there are many things researchers still do not understand. Remarkably, the majority of the Universe is made up of dark matter and dark energy, of which no one has been able to identify its nature. A promising avenue to solve these mysteries is the structure of the Universe. Today’s Universe is made up of filaments where galaxies cluster together and look like threads from far away, and voids where there appears to be nothing (image 1). The discovery of the cosmic microwave background has given researchers a snapshot of what the Universe looked like close to its beginning, and understanding how its structure evolved to what it is today would reveal valuable characteristics about what dark matter and dark energy is.

    A team of researchers, including Kyoto University Yukawa Institute for Theoretical Physics Project Associate Professor Takahiro Nishimichi, and Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU) Principal Investigator Masahiro Takada, used the world’s fastest astrophysical simulation supercomputers ATERUI and ATERUI II to develop the Dark Emulator. Using the emulator on data recorded by several of the world’s largest observational surveys allows researchers to study possibilities concerning the origin of cosmic structures, and how dark matter distribution could have changed over time.

    “We built an extraordinarily large database using a supercomputer, which took us three years to finish, but now we can recreate it on a laptop in a matter of seconds. I feel like there is great potential in data science. Using this result, I hope we can work our way towards uncovering the greatest mystery of modern physics, which is to uncover what dark energy is. I also think this method we’ve developed will be useful in other fields such as natural sciences or social sciences,” says lead author Nishimichi.

    This tool uses an aspect of artificial intelligence called machine learning. By changing several important characteristics of the Universe, such as those of dark matter and dark energy, ATERUI and ATERUI II have created hundreds of virtual Universes. Dark Emulator learns from the data, and guesses outcomes for new sets of characteristics without having to create entirely new simulations every time. When testing the resulting tool with real life surveys, it was able to successfully predict weak gravitational lensing effects in the Hyper Suprime-Cam survey, along with the three-dimensional galaxy distribution patterns recorded in the Sloan Digital Sky Survey to within 2 to 3 per cent accuracy, in a matter of seconds. In comparison, running simulations individually through a supercomputer without the AI, would take several days.

    The researchers hope to apply their tool using data from upcoming surveys in the 2020s, enabling deeper studies of the origin on the Universe.

    Details of their study were published in The Astrophysical Journal on 8 October, 2019.

    See the full Kavli IPMU article here .
    See the full NAOJ article here .
    See the full Center for Computational Astrophysics here .

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    Kavli IPMU (Kavli Institute for the Physics and Mathematics of the Universe -Tokyo) is an international research institute with English as its official language. The goal of the institute is to discover the fundamental laws of nature and to understand the Universe from the synergistic perspectives of mathematics, astronomy, and theoretical and experimental physics. The Institute for the Physics and Mathematics of the Universe (IPMU) was established in October 2007 under the World Premier International Research Center Initiative (WPI) of the Ministry of Education, Sports, Science and Technology in Japan with the University of Tokyo as the host institution. IPMU was designated as the first research institute within the University of Tokyo Institutes for Advanced Study (UTIAS) in January 2011. It received an endowment from The Kavli Foundation and was renamed the “Kavli Institute for the Physics and Mathematics of the Universe” in April 2012. Kavli IPMU is located on the Kashiwa campus of the University of Tokyo, and more than half of its full-time scientific members come from outside Japan. http://www.ipmu.jp/

    The Kavli Foundation, based in Oxnard, California, is dedicated to the goals of advancing science for the benefit of humanity and promoting increased public understanding and support for scientists and their work.

    The Foundation’s mission is implemented through an international program of research institutes, professorships, and symposia in the fields of astrophysics, nanoscience, neuroscience, and theoretical physics as well as prizes in the fields of astrophysics, nanoscience, and neuroscience.

     
  • richardmitnick 8:27 am on December 30, 2019 Permalink | Reply
    Tags: "Planets Around a Black Hole?―Calculations Show Possibility of Bizarre Worlds", , , , , NAOJ   

    From National Astronomical Observatory of Japan: “Planets Around a Black Hole?―Calculations Show Possibility of Bizarre Worlds” 

    NAOJ

    From National Astronomical Observatory of Japan

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    Artist’s impression of planets orbiting a supermassive black hole. (Credit: Kagoshima University)

    Theoreticians in two different fields defied the common knowledge that planets orbit stars like the Sun. They proposed the possibility of thousands of planets around a supermassive black hole.

    “With the right conditions, planets could be formed even in harsh environments, such as around a black hole,” says Keiichi Wada, a professor at Kagoshima University researching active galactic nuclei which are luminous objects energized by black holes.

    According to the latest theories, planets are formed from fluffy dust aggregates in a protoplanetary disk around a young star. But young stars are not the only objects that possess dust disks. In a novel approach, the researchers focused on heavy disks around supermassive black holes in the nuclei of galaxies.

    “Our calculations show that tens of thousands of planets with 10 times the mass of the Earth could be formed around 10 light-years from a black hole,” says Eiichiro Kokubo, a professor at the National Astronomical Observatory of Japan who studies planet formation. “Around black holes there might exist planetary systems of astonishing scale.”

    Some supermassive black holes have large amounts of matter around them in the form of a heavy, dense disk. A disk can contain as much as a hundred thousand times the mass of the Sun worth of dust. This is a billion times the dust mass of a protoplanetary disk.

    n a low temperature region of a protoplanetary disk, dust grains with ice mantles stick together and evolve into fluffy aggregates. A dust disk around a black hole is so dense that the intense radiation from the central region is blocked and low temperature regions are formed. The researchers applied the planet formation theory to circumnuclear disks and found that planets could be formed in several hundred million years.

    Currently there are no techniques to detect these planets around black holes. However, the researchers expect this study to open a new field of astronomy.

    This research published on November 26, 2019 in The Astrophysical Journal.

    See the full article here .

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    Please help promote STEM in your local schools.

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    NAOJ

    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

    NAOJ/Subaru Telescope at Mauna Kea Hawaii, USA,4,207 m (13,802 ft) above sea level


    ESO/NRAO/NAOJ ALMA Array
    ESO/NRAO/NAOJ ALMA Array
    sft
    Solar Flare Telescope

    Nobeyama Radio Telescope - Copy
    Nobeyama Radio Observatory

    Nobeyama Solar Radio Telescope Array
    Nobeyama Radio Observatory: Solar

    Misuzawa Station Japan
    Mizusawa VERA Observatory

    NAOJ Okayama Astrophysical Observatory Telescope
    Okayama Astrophysical Observatory

     
  • richardmitnick 10:14 am on December 19, 2019 Permalink | Reply
    Tags: "The ‘cores’ of massive galaxies had already formed 1.5 billion years after the Big Bang", , , , , NAOJ   

    From National Astronomical Observatory of Japan: “The ‘cores’ of massive galaxies had already formed 1.5 billion years after the Big Bang” 

    NAOJ

    From National Astronomical Observatory of Japan

    December 19, 2019

    1
    A blow-up of a small portion of the Subaru/XMM-Newton Deep Field. The red galaxy at the center is a dying galaxy at 12 billion years ago. Astronomers measured the motion of stars in the galaxy and found that the core of the galaxy is nearly fully formed.

    A distant galaxy more massive than our Milky Way—with more than a trillion stars—has revealed that the ‘cores’ of massive galaxies in the Universe had formed already 1.5 billion years after the Big Bang, about 1 billion years earlier than previous measurements revealed.

    Researchers published their analysis on November 6 in The Astrophysical Journal Letters, a journal of the American Astronomical Society.

    “If we point a telescope to the sky and take a deep image, we can see so many galaxies out there,” said Masayuki Tanaka, paper author and associate professor of astronomical science in the Graduate University for Advanced Studies and the National Astronomical Observatory of Japan. “But our understanding of how these galaxies form and grow is still quite limited—especially when it comes to massive galaxies.”

    Galaxies are broadly categorized as dead or alive: dead galaxies are no longer forming stars, while living galaxies are still bright with star formation activity. A ‘quenching’ galaxy is a galaxy in the process of dying—meaning its star formation is significantly suppressed. Quenching galaxies are not as bright as fully alive galaxies, but they’re not as dark as dead galaxies. Researchers use this spectrum of brightness as the first line of identification when observing the Universe.

    The researchers used the telescopes at the W.M. Keck Observatory in Hawai‘i to observe a quenching galaxy in what is called the Subaru/XMM-Newton Deep Field.

    Keck Observatory, operated by Caltech and the University of California, Maunakea Hawaii USA, 4,207 m (13,802 ft)

    This region of the sky has been closely observed by several telescopes, producing a wealth of data for scientists to study. Tanaka and his team used an instrument called MOSFIRE on the Keck I telescope to obtain measurements of the galaxy.

    Keck/MOSFIRE on Keck 1, Mauna Kea, Hawaii, USA

    They obtained a two-micron measurement in the near-infrared spectrum, which the human eye cannot see, but it confirmed that the light from the galaxy was emitted just 1.5 billion years after the Big Bang. The team also confirmed that the galaxy’s star formation was suppressed.

    “The suppressed star formation tells you that a galaxy is dying, sadly, but that is exactly the kind of galaxy we want to study in detail to understand why quenching occurs,” said Francesco Valentino, a co-author of the paper and an assistant professor at the Cosmic Dawn Center in Copenhagen.

    According to Valentino, astronomers believe that massive galaxies are the first to die in the history of the Universe and that they hold the key to understanding why quenching occurs in the first place.

    “We also found that the ‘cores’ of massive galaxies today seem to be fully formed in the early Universe,” Tanaka said. How stars move within a galaxy depends on how much mass that object contains. Tanaka and his team found that the stars in the distant galaxy seem to move just as quickly as those closer to home. “The previous measurement of this kind was made when the Universe was 2.5 billion years old. We pushed the record up to 1.5 billion years and found, to our surprise, that the core was already pretty mature.”

    The researchers are continuing to investigate how massive galaxies form and how they die in the early Universe, and they are searching for more massive quenching galaxies in the distant Universe that may shed light on earlier phases of the process.

    “When did the first dead galaxy appear in the Universe?” Tanaka asked. “This is a very interesting question for us to address. To do so, we will continue to observe the deep sky with the largest telescopes and expand our search as more advanced facilities become available.”

    See the full article here .

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    Please help promote STEM in your local schools.

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    NAOJ

    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

    NAOJ/Subaru Telescope at Mauna Kea Hawaii, USA,4,207 m (13,802 ft) above sea level


    ESO/NRAO/NAOJ ALMA Array
    ESO/NRAO/NAOJ ALMA Array
    sft
    Solar Flare Telescope

    Nobeyama Radio Telescope - Copy
    Nobeyama Radio Observatory

    Nobeyama Solar Radio Telescope Array
    Nobeyama Radio Observatory: Solar

    Misuzawa Station Japan
    Mizusawa VERA Observatory

    NAOJ Okayama Astrophysical Observatory Telescope
    Okayama Astrophysical Observatory

     
  • richardmitnick 11:37 am on July 24, 2019 Permalink | Reply
    Tags: "Production Sites of Stars are Rare", , , , , High-density gas- the material for stars- accounts for only 3% of the total mass of gas distributed in the Milky Way, , NAOJ, Nobeyama Radio Obeservatory (NRO) 45-m telescope   

    From National Astronomical Observatory of Japan: “Production Sites of Stars are Rare” 

    NAOJ

    From National Astronomical Observatory of Japan

    1
    Distribution of gas clouds obtained from the FUGIN project. The high-density gas (right) is detected only in small parts of the low-density gas (left). (Credit: NAOJ)

    Astronomers using the Nobeyama Radio Obeservatory (NRO) 45-m telescope [below] found that high-density gas, the material for stars, accounts for only 3% of the total mass of gas distributed in the Milky Way. This result provides key information for understanding the unexpectedly low production rate of stars.

    Milky Way Credits: NASA/JPL-Caltech /ESO R. Hurt. The bar is visible in this image

    Stars are born in gas clouds. The high-density gas pockets form in the extended, low-density gas clouds, and stars form in the very dense gas cores which evolve within the high-density gas. However, observations of distant galaxies detected 1000 times fewer stars than the production value expected from the total amount of low-density gas. To interpret the discrepancy, observations which detect both of the high-density and low-density gas with high-spatial resolution and wide area coverage were needed. However, such observations are difficult, because the high-density gas structures are dozens of times smaller than the low-density gas structures.

    The Milky Way survey project “FUGIN” conducted using the NRO 45-m telescope and the multi-beam receiver FOREST overcame these difficulties. Kazufumi Torii, a project assistant professor at NAOJ, and his team analyzed the big data obtained in the FUGIN project, and measured the accurate masses of the low-density and high-density gas for a large span of 20,000 light-years along the Milky Way. They revealed for the first time that the high-density gas accounts for only 3% of the total gas.

    These results imply the production rate of high-density gas in the low-density gas clouds is small, creating only a small number of opportunities to form stars. The researcher team will continue working on the FUGIN data to investigate the cause of inefficient formation of the high-density gas.

    Science paper PASJ

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    NAOJ

    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

    NAOJ/Subaru Telescope at Mauna Kea Hawaii, USA,4,207 m (13,802 ft) above sea level


    ESO/NRAO/NAOJ ALMA Array
    ESO/NRAO/NAOJ ALMA Array
    sft
    Solar Flare Telescope

    Nobeyama Radio Telescope - Copy
    Nobeyama Radio Observatory

    Nobeyama Solar Radio Telescope Array
    Nobeyama Radio Observatory: Solar

    Misuzawa Station Japan
    Mizusawa VERA Observatory

    NAOJ Okayama Astrophysical Observatory Telescope
    Okayama Astrophysical Observatory

     
  • richardmitnick 2:21 pm on June 26, 2019 Permalink | Reply
    Tags: "ALMA Pinpoints the Formation Site of Planet around Nearest Young Star", , , , , , NAOJ   

    From ALMA via NAOJ: “ALMA Pinpoints the Formation Site of Planet around Nearest Young Star” 

    NAOJ

    From National Astronomical Observatory of Japan

    NAOJ

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres

    From ALMA

    June 26, 2019

    1
    ALMA image of the protoplanetary disk around the young star TW Hydrae. A small clump of dust was found in the southwestern (bottom right) part of the otherwise highly symmetric disk.

    Researchers using ALMA (Atacama Large Millimeter/submillimeter Array) found a small dust concentration in the disk around TW Hydrae, the nearest young star. It is highly possible that a planet is growing or about to be formed in this concentration. This is the first time that the exact place where cold materials are forming the seed of a planet has been pinpointed in the disk around a young star.

    The young star TW Hydrae, located194 light-years away in the constellation Hydra, is the closest star around which planets may be forming. Its surrounding dust disk is the best target to study the process of planet formation.

    Previous ALMA observations revealed that the disk is composed of concentric rings. Now, new higher sensitivity ALMA observations revealed a previously unknown small clump in the planet forming disk. The clump is elongated along the direction of the disk rotation, with a width approximately equal to the distance between the Sun and the Earth, and a length of about four-and-a-half times that.

    “The true nature of the clump is still not clear,” says Takashi Tsukagoshi at the National Astronomical Observatory of Japan and the lead author of the research paper. “It could be a ‘circumplanetary’ disk feeding a Neptune-sized infant planet. Or it might be that swirling gas is raking up the dust particles.”

    Planets form in disks of gas and dust around young stars. Micrometer-sized dust particles stick together to grow to larger grains, rocks, and finally a planet. Theoretical studies predict that an infant planet is surrounded by a ‘circumplanetary’ disk, a small structure within the larger dust disk around the star. The planet collects material through this circumplanetary disk. It is important to find such a circumplanetary disk to understand the final stage of planet growth.

    Cold dust and gas in the disks around young stars are difficult to see in visible light, but they emit radio waves. With its high sensitivity and resolution for such radio waves, ALMA is one of the most powerful instruments to study the genesis of planets.

    However, the brightness and elongated shape of the structure revealed by ALMA don’t exactly match theoretical predictions for circumplanetary disks. It might be a gas vortex, which are also expected to form here and there around a young star. Finding only a single dust clump at this time is also contrary to theoretical studies. So the research team could not reach a definitive answer on the nature of the dusty clump.

    “Although we do not have a robust conclusion,” says Tsukagoshi. “Pinpointing the exact place of planet formation is highly valuable to us. Next we’ll obtain even higher resolution ALMA images to reveal the temperature distribution in the clump to look for hints of a planet inside. Also we plan to observe it with the Subaru Telescope in infrared to see if there is hot gas around a potential planet.”

    These observation results were published as T. Tsukagoshi et al. “Discovery of an au-scale excess in millimeter emission from the protoplanetary disk around TW Hya” in the Astrophysical Journal Letters on June 10, 2019.

    The research team members are:
    Takashi Tsukagoshi (National Astronomical Observatory of Japan), Takayuki Muto (Kogakuin University), Hideko Nomura (Tokyo Institute of Technology/National Astronomical Observatory of Japan), Ryohei Kawabe (National Astronomical Observatory of Japan/SOKENDAI/The University of Tokyo), Kazuhiro D. Kanagawa (The University of Tokyo), Satoshi Okuzumi (Tokyo Institute of Technology), Shigeru Ida (Tokyo Institute of Technology), Catherine Walsh (University of Leeds), Tom J. Millar (Queen’s University Belfast), Sanemichi Z. Takahashi (National Astronomical Observatory of Japan/Kogakuin University), Jun Hashimoto (Astrobiology Center), Taichi Uyama (California Institute of Technology/The University of Tokyo/National Astronomical Observatory of Japan), and Motohide Tamura (The University of Tokyo/Astrobiology Center)

    This research was supported by JSPS KAKENHI (No. 17K14244, 17H01103, 18H05441, 19K03932), STFC (ST/P000321/1, ST/R000549/1).

    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), 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

    NAOJ

    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

     
  • richardmitnick 11:04 am on June 2, 2019 Permalink | Reply
    Tags: "Subaru Telescope Captures 1800 Exploding Stars", , , , , NAOJ,   

    From National Astronomical Observatory of Japan: “Subaru Telescope Captures 1800 Exploding Stars” 

    NAOJ

    From National Astronomical Observatory of Japan

    2
    Some supernovae discovered in this study. There are three images for each supernova: before it exploded (left), after it exploded (middle), and the supernova itself (difference between the first two images).

    Astronomers using the Subaru Telescope identified about 1800 new supernovae in the distant Universe, including 58 Type Ia supernovae over 8 billion light-years away. These findings will help elucidate the expansion of the Universe.

    A supernova is a powerful explosion at the end of the life of a massive star. The star often becomes as bright as its host galaxy, shining one billion times brighter than the Sun for one to six months before dimming down. Type Ia supernovae are particularly useful because their consistent maximum brightness allows researchers to calculate how far the star is from Earth. This is particularly useful for researchers who want to measure the expansion of the Universe.

    But supernovae are rare events. To spot as many supernovae as possible, a team led by Professor Naoki Yasuda of the Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU) used the Subaru Telescope equipped with Hyper Suprime-Cam, an 870 mega-pixel digital camera, to capture sharp stellar images over a very wide area of the night sky. By taking repeated images of the same area of the night sky over a six month period, the researchers could identify new supernovae by looking for stars that suddenly appeared brighter before gradually fading out.

    The team identified about 400 Type Ia supernovae. Fifty-eight of these Type Ia supernovae are located more than 8 billion light-years away from Earth. In comparison, the Hubble Space Telescope took about 10 years to discover a total of 50 supernovae located more than 8 billion light-years away.

    “The Subaru Telescope and Hyper Suprime-Cam have already helped researchers create a 3D map of dark matter, and observation of primordial black holes, but now this result proves that this instrument has a very high capability finding supernovae very, very far away from Earth.” said Yasuda.

    Next, researchers will use the data to calculate the expansion of the Universe more accurately and study how dark energy’s effect on that expansion has changed over time.

    These findings were published as “The Hyper Suprime-Cam SSP Transient Survey in COSMOS: Overview” in the PASJ on May 30, 2019.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    NAOJ

    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

    NAOJ/Subaru Telescope at Mauna Kea Hawaii, USA,4,207 m (13,802 ft) above sea level


    ESO/NRAO/NAOJ ALMA Array
    ESO/NRAO/NAOJ ALMA Array
    sft
    Solar Flare Telescope

    Nobeyama Radio Telescope - Copy
    Nobeyama Radio Observatory

    Nobeyama Solar Radio Telescope Array
    Nobeyama Radio Observatory: Solar

    Misuzawa Station Japan
    Mizusawa VERA Observatory

    NAOJ Okayama Astrophysical Observatory Telescope
    Okayama Astrophysical Observatory

     
  • richardmitnick 11:21 am on January 16, 2019 Permalink | Reply
    Tags: Astronomers Have Found Evidence of a Big Black Hole Wandering Our Galaxy, , , , , NAOJ   

    From National Astronomical Observatory of Japan via Science Alert: “Astronomers Have Found Evidence of a Big Black Hole Wandering Our Galaxy” 

    NAOJ

    From National Astronomical Observatory of Japan

    via

    ScienceAlert

    Science Alert

    16 JAN 2019
    MICHELLE STARR

    1
    (OzGrav ARC Centre of Excellence/YouTube)

    The peculiar movement of gas at the galactic centre could be the smoking gun that finally leads astronomers to the most elusive type of black hole – the middleweight.

    Black holes are pretty hard to find unless they’re actively feeding (or colliding), since they don’t emit any electromagnetic radiation (except perhaps for Hawking radiation, which, if it exists, we can’t detect).

    That’s because electromagnetic radiation can’t achieve escape velocity from beyond the event horizon; thus black holes are invisible to our detection methods when they’re not doing something noticeable.

    Still, we know there are stellar mass black holes, formed from the core collapse of a massive star, up to about 100 times the mass of the Sun; and supermassive black holes, starting from about 100,000 times the mass of the Sun.

    Between these two extremes, though, is a whopping question mark. Although there has been pretty good indirect evidence that points to the existence of black holes between 100 and 100,000 solar masses, their existence has yet to be confirmed.

    In other words, those black holes of unusual size? We’re not sure they exist.

    In a new paper published on preprint resource arXiv, and yet to be peer-reviewed, astronomers from the National Astronomical Observatory of Japan (NAOJ) have described evidence that points to one of these mythical beasts drifting around about 20 light-years from the centre of the Milky Way.

    Using the Atacama Large Millimeter/Submillimeter Array (ALMA) radio telescope, they found streams of molecular gas orbiting what seems to be an invisible massive object.

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres

    “When I checked the ALMA data for the first time,” astrophysicist Shunya Takekawa of the NAOJ told New Scientist, “I was really excited because the observed gas showed obvious orbital motions, which strongly suggest an invisible massive object lurking.”

    Similar high-velocity compact clouds have been observed as a result of collisions between supernova clouds, but the object – called HCN–0.009–0.044 – shows neither the shape nor the expansion pattern associated with a collision of this type.

    Moreover, previous research, also from the NAOJ and co-authored by the team conducting this new research, had already identified HCN–0.009–0.044 as a possible black hole.

    But now they’ve done something new. Based on the shape and movement of the gas streams, the team was able to infer that the object has a mass equivalent of around 32,000 Suns.

    This makes it – if the paper passes peer review – a very strong contender for a black hole missing link, packing all that mass into an object roughly the size of Jupiter.

    In addition to potentially discovering an intermediate black hole, the research points to what could be a new method of discovering inactive black holes.

    As well as the motion of the gas, ionisation of the gas in the inner part of the orbit suggests that at some point, either photoionisation, dissociative shock, or both took place – ionisation processes seen in active black holes.

    So if a black hole is intermittently active, it may produce ionisation that can be detected after it has quietened down again.

    “Our results provide new circumstantial evidences for a wandering intermediate-mass black hole in the Galactic centre, suggesting also that high-velocity compact clouds can be probes of quiescent black holes abound in our Galaxy,” the researchers wrote in their paper.

    “[H]igh-resolution observations of compact high-velocity gas features have the potential to increase the number of candidates for non-luminous black holes, providing a new perspective to search for the missing black holes.”

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    NAOJ

    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

    NAOJ/Subaru Telescope at Mauna Kea Hawaii, USA,4,207 m (13,802 ft) above sea level


    ESO/NRAO/NAOJ ALMA Array
    ESO/NRAO/NAOJ ALMA Array
    sft
    Solar Flare Telescope

    Nobeyama Radio Telescope - Copy
    Nobeyama Radio Observatory

    Nobeyama Solar Radio Telescope Array
    Nobeyama Radio Observatory: Solar

    Misuzawa Station Japan
    Mizusawa VERA Observatory

    NAOJ Okayama Astrophysical Observatory Telescope
    Okayama Astrophysical Observatory

     
  • richardmitnick 6:25 pm on December 17, 2018 Permalink | Reply
    Tags: 1.52-m Telescopio Carlos Sánchez at the Teide Observatory Canaries Spain, MuSCAT2-a powerful 4-color simultaneous camera, NAOJ,   

    From National Astronomical Observatory of Japan: “MuSCAT2 to find Earth-like Planets in the TESS Era” 

    NAOJ

    From National Astronomical Observatory of Japan

    December 17, 2018

    1
    Newly Developed simultaneous multi-color camera MuSCAT2 on the 1.52-m Telescopio Carlos Sánchez at the Teide Observatory, Canaries, Spain

    2
    3
    1.52-m Telescopio Carlos Sánchez at the Teide Observatory, Canaries, Spain

    A Japan-Spain team has developed a powerful 4-color simultaneous camera named MuSCAT2 for the 1.52-m Telescopio Carlos Sánchez at the Teide Observatory, Canaries, Spain. The instrument aims to find a large number of transiting exoplanets, including Earth-like habitable planets orbiting stars near the Sun, in collaboration with NASA’s Transiting Exoplanet Survey Satellite (TESS) launched in April 2018.

    NASA/MIT TESS

    In April 2018, NASA launched a new satellite named Transiting Exoplanet Survey Satellite (TESS) to discover new exoplanets around stars near the Sun. TESS finds exoplanets by observing planetary transits, a phenomenon in which a planet passes in front of its host star and blocks part of the star’s light.

    Planet transit. NASA/Ames

    Transiting exoplanets are especially valuable targets for exoplanet studies, since they provide information about the true mass, radius, density, orbital obliquity, and atmosphere of such planets.

    However, transiting exoplanet candidates discovered by TESS are not always real planets. An eclipsing binary, a pair of stars orbiting and eclipsing each other, can also produce transit-like signals. For the TESS mission, the false positive rate caused by eclipsing binaries is predicted to be 30-70% depending on the direction observed. Follow up observations can help distinguish actual exoplanets from false positives.

    Multi-color transit observations are one way to separate exoplanets from eclipsing binary stars. This is because in the case of an eclipsing binary, the light coming from the system changes color as it dims, while for an exoplanet transit the light stays the same color as it dims.

    For this reason, an international team, consisting of Japanese researchers from the Astrobiology Center (ABC) and the University of Tokyo and Spanish researchers from the Instituto de Astrofísica de Canarias (IAC), has developed a 4-color simultaneous camera named MuSCAT2 (2nd generation Multi-color Simultaneous Camera for studying Atmospheres of Transiting exoplanets) on the 1.52-m Telescopio Carlos Sánchez at the Teide Observatory, Canaries, Spain.

    The team will use MuSCAT2 more than 162 nights per year until at least 2022. They will work to confirm a large number of new transiting exoplanets, including Earth-like habitable planets orbiting stars near the Sun, in collaboration with the ongoing TESS mission.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    NAOJ

    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

    NAOJ/Subaru Telescope at Mauna Kea Hawaii, USA,4,207 m (13,802 ft) above sea level


    ESO/NRAO/NAOJ ALMA Array
    ESO/NRAO/NAOJ ALMA Array
    sft
    Solar Flare Telescope

    Nobeyama Radio Telescope - Copy
    Nobeyama Radio Observatory

    Nobeyama Solar Radio Telescope Array
    Nobeyama Radio Observatory: Solar

    Misuzawa Station Japan
    Mizusawa VERA Observatory

    NAOJ Okayama Astrophysical Observatory Telescope
    Okayama Astrophysical Observatory

     
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