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  • richardmitnick 2:02 pm on November 7, 2019 Permalink | Reply
    Tags: "Astronomers Catch Wind Rushing Out of Galaxy", , , , , , Makani, UCSD - University of Californa San Diego   

    From Keck Observatory: “Astronomers Catch Wind Rushing Out of Galaxy” 

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

    From Keck Observatory

    Researchers Directly Observe for the First Time a Huge Outflow of Gas Extending Far Beyond a Galaxy.

    Exploring the influence of galactic winds from a distant galaxy called Makani, University of California, San Diego’s Alison Coil, Rhodes College’s David Rupke and a group of collaborators from around the world made a novel discovery using W. M. Keck Observatory on Hawaii Island.

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    Makani. Astronomers Observe Giant Outflow of Gas Extending Far Beyond Compact Galaxy

    Published online today in the journal Nature, their study’s findings provide direct evidence for the first time of the role of galactic winds—ejections of gas from galaxies—in creating the circumgalactic medium (CGM). It exists in the regions around galaxies, and it plays an active role in their cosmic evolution. The unique composition of Makani—meaning ‘wind’ in Hawaiian—uniquely lent itself to the breakthrough findings.

    “Makani is not a typical galaxy,” noted Coil, a physics professor at UC San Diego. “It’s what’s known as a late-stage major merger—two recently combined similarly massive galaxies, which came together because of the gravitational pull each felt from the other as they drew nearer. Galaxy mergers often lead to starburst events, when a substantial amount of gas present in the merging galaxies is compressed, resulting in a burst of new star births. Those new stars, in the case of Makani, likely caused the huge outflows—either in stellar winds or at the end of their lives when they exploded as supernovae.”

    A volume rendering of the KCWI data cube revealing the structure of Makani. Credit: David Tree & Peter Richardson, Games and Visual Effects Research Lab, University of Hertfordshire

    Coil explained that most of the gas in the universe inexplicably appears in the regions surrounding galaxies—not in the galaxies. Typically, when astronomers observe a galaxy, they are not witnessing it undergoing dramatic events—big mergers, the rearrangement of stars, the creation of multiple stars or driving huge, fast winds.

    “While these events may occur at some point in a galaxy’s life, they’d be relatively brief,” noted Coil. “Here, we’re actually catching it all right as it’s happening through these huge outflows of gas and dust.”

    Coil and Rupke, the paper’s first author, used data collected from one of Keck Observatory’s newest instruments – the Keck Cosmic Web Imager (KCWI) – combined with images from the Hubble Space Telescope and the Atacama Large Millimeter Array (ALMA), to draw their conclusions.

    Keck Cosmic Web Imager on Keck 2

    NASA/ESA Hubble Telescope

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

    The KCWI data provided what the researchers call the “stunning detection” of the ionized oxygen gas to extremely large scales, well beyond the stars in the galaxy. It allowed them to distinguish a fast gaseous outflow launched from the galaxy a few million years ago, from a gas outflow launched hundreds of millions of years earlier that has since slowed significantly.

    “The earlier outflow has flowed to large distances from the galaxy, while the fast, recent outflow has not had time to do so,” summarized Rupke, associate professor of physics at Rhodes College.

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    Figure 1: The giant galactic wind surrounding the massive, compact galaxy Makani. The colors and white contour lines show the amount of light emitted by the ionized gas from different parts of the oxygen nebula, from brightest (white) to faintest (purple). The middle part of the image (black) shows the full extent of the galaxy, though most of the galaxy is concentrated at the center (the tiny green circle). The axes show distance from the center of the galaxy in kiloparsecs. Figure by: Gene Leung (UC San Diego)

    From Hubble, the researchers procured images of Makani’s stars, showing it to be a massive, compact galaxy that resulted from a merger of two once separate galaxies. From ALMA, they could see that the outflow contains molecules as well as atoms. The data sets indicated that with a mixed population of old, middle-age and young stars, the galaxy might also contain a dust-obscured accreting supermassive black hole. This suggests to the scientists that Makani’s properties and timescales are consistent with theoretical models of galactic winds.

    “In terms of both their size and speed of travel, the two outflows are consistent with their creation by these past starburst events; they’re also consistent with theoretical models of how large and fast winds should be if created by starbursts. So observations and theory are agreeing well here,” noted Coil.

    Rupke noticed that the hourglass shape of Makani’s nebula is strongly reminiscent of similar galactic winds in other galaxies, but that Makani’s wind is much larger than in other observed galaxies.

    “This means that we can confirm it’s actually moving gas from the galaxy into the circumgalactic regions around it, as well as sweeping up more gas from its surroundings as it moves out,” Rupke explained. “And it’s moving a lot of it—at least one to 10 percent of the visible mass of the entire galaxy—at very high speeds, thousands of kilometers per second.”

    Rupke also noted that while astronomers are converging on the idea that galactic winds are important for feeding the CGM, most of the evidence has come from theoretical models or observations that don’t encompass the entire galaxy.

    “Here we have the whole spatial picture for one galaxy, which is a remarkable illustration of what people expected,” he said. “Makani’s existence provides one of the first direct windows into how a galaxy contributes to the ongoing formation and chemical enrichment of its CGM.”

    3
    Figure 2: The multiphase galactic wind: comparison of the ionized, neutral atomic and molecular gas. In the zoomed-in view of the inner 40 kiloparsecs at the upper right, molecular gas emission from carbon monoxide (green contours) is plotted on emission from magnesium atoms that trace neutral atomic gas (color, with white contours) in the same velocity range (-500 to +500 kilometers per second, where negative velocities are blueshifted and positive velocities redshifted with respect to the galaxy). The zoomed-in view at the lower left compares the emission from low-velocity molecules and ionized oxygen atoms, and the high-velocity molecular and ionized gas are shown at lower right. The molecules, neutral atoms and ionized gas all correspond well spatially, though the ionized gas extends far beyond the other two gas phases. Figure by: David Rupke (Rhodes College)

    This study was supported by the National Science Foundation (collaborative grant AST-1814233, 1813365, 1814159 and 1813702), NASA (award SOF-06-0191, issued by USRA), Rhodes College and the Royal Society.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    Stem Education Coalition

    Mission
    To advance the frontiers of astronomy and share our discoveries with the world.

    The W. M. Keck Observatory operates the largest, most scientifically productive telescopes on Earth. The two, 10-meter optical/infrared telescopes on the summit of Mauna Kea on the Island of Hawaii feature a suite of advanced instruments including imagers, multi-object spectrographs, high-resolution spectrographs, integral-field spectrometer and world-leading laser guide star adaptive optics systems. Keck Observatory is a private 501(c) 3 non-profit organization and a scientific partnership of the California Institute of Technology, the University of California and NASA.

    Today Keck Observatory is supported by both public funding sources and private philanthropy. As a 501(c)3, the organization is managed by the California Association for Research in Astronomy (CARA), whose Board of Directors includes representatives from the California Institute of Technology and the University of California, with liaisons to the board from NASA and the Keck Foundation.


    Keck UCal

     
  • richardmitnick 4:47 pm on November 6, 2018 Permalink | Reply
    Tags: Physicists Race to Demystify Einstein’s ‘Spooky’ Science, , UCSD - University of Californa San Diego   

    From UC San Diego: “Physicists Race to Demystify Einstein’s ‘Spooky’ Science” 

    UC San Diego bloc

    From UC San Diego

    August 20, 2018

    Cynthia Dillon
    858-822-0142
    cdillon@ucsd.edu

    International research team recasts timeline, dating from the Big Bang, of possible quantum theory alternatives.

    When it comes to fundamental physics, things can get spooky. At least that’s what Albert Einstein said when describing the phenomenon of quantum entanglement—the linkage of particles in such a way that measurements performed on one particle seem to affect the other, even when separated by great distances. “Spooky action at a distance” is how Einstein described what he couldn’t explain.

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    Schematic of the 2018 “Cosmic Bell” experiment at the Roque de Los Muchachos Observatory in the Canary Islands, where two large telescopes observed the fluctuating color of light from distant quasars (red and blue galaxies). The green beams indicate polarization-entangled photons sent through the open air between stations separated by about one kilometer. Image by Andrew S. Friedman and Dominik Rauch.

    While quantum mechanics includes many mysterious phenomena like entanglement, it remains the best fundamental physical theory describing how matter and light behave at the smallest scales. Quantum theory has survived numerous experimental tests in the past century while enabling many advanced technologies: modern computers, digital cameras and the displays of TVs, laptops and smartphones. Quantum entanglement itself is also the key to several next-generation technologies in computing, encryption and telecommunications. Yet, there is no clear consensus on how to interpret what quantum theory says about the true nature of reality at the subatomic level, or to definitively explain how entanglement actually works.

    2
    Diagram of a run of the Cosmic Bell test. The regions of space and time where an alternative, non-quantum mechanism could still have acted (limited to the red and/or blue regions) corresponds to at least 7.78 billion years ago (blue region). Light from the more distant quasar was emitted 12.21 billion years ago (red region). Compared to the gray region, representing all of space and time prior to the experiment, the alternatives are limited to within four percent of the space-time volume since the Big Bang. Image by Andrew Friedman and David Leon.

    According to Andrew Friedman, a research scientist at the University of California San Diego Center for Astrophysics and Space Sciences (CASS), “the race is on” around the globe to identify and experimentally close potential loopholes that could still allow alternative theories, distinct from quantum theory, to explain perplexing phenomena like quantum entanglement. Such loopholes could potentially allow future quantum encryption schemes to be hacked. So, Friedman and his fellow researchers conducted a “Cosmic Bell” test with polarization-entangled photons designed to further close the “freedom-of-choice” or “free will” loophole in tests of Bell’s inequality, a famous theoretical result derived by physicist John S. Bell in the 1960s. Published in the Aug. 20 issue of Physical Review Letters, their findings are consistent with quantum theory and push back to at least 7.8 billion years ago the most recent time by which any causal influences from alternative, non-quantum mechanisms could have exploited the freedom-of-choice loophole.

    “Our findings imply that any such mechanism is excluded from explaining the results from within a whopping 96% of the space-time volume in the causal past of our experiment, stretching all the way from the Big Bang until today,” said Friedman. “While these alternatives to quantum theory have not been completely ruled out, we are pushing them into a progressively smaller corner of space and time.”

    In their experiment, the researchers outsourced the choice of entangled photon measurements to the universe. They did this by using the color of light that has been traveling to Earth for billions of years from distant galaxies—quasars—as a “cosmic random number generator.”

    “This is a rare experiment that comes along only very seldomly in a scientist’s career: a pioneering experiment that sets the bar so high few, if any, competitors can ever match it,” noted UC San Diego astrophysicist Brian Keating. “I’m so proud that my graduate student David Leon had the chance to make a significant contribution to this fascinating research, co-led by CASS research scientist, Dr. Andrew Friedman.”

    Besides UC San Diego’s Friedman and Leon, the full research team included lead author and Ph.D. student Dominik Rauch, along with Anton Zeilinger and his experimental quantum optics group from the University of Vienna; theoretical physicists David Kaiser and Alan Guth at MIT; Jason Gallicchio and his experimental physics group at Harvey Mudd College, and others. Expanding upon their previous quantum entanglement experiments [Physical Review Letters], Friedman and colleagues went to great effort to choose entangled particle measurements using 3.6 and 4.2 meter telescopes in the Canary Islands, allowing them to collect sufficient light from the much fainter, distant quasars.

    To conduct their test, they shined laser light into a special crystal that generated pairs of entangled photons, which the scientists repeatedly sent through the open air toward both telescopes. From the quasar light collected, the scientists could choose polarization measurement settings while each entangled photon was in mid-flight. The group was allotted three nights and a few hours at the Roque de los Muchachos Observatory in La Palma, amidst operationally challenging conditions including freezing rain, high winds, and uncertainty about whether they would have enough time to complete the experiment. Additionally, Friedman and colleagues had to write software that could choose the best quasars to observe on-the-fly—from a database of more than 1.5 million—and predict the observation time needed to obtain a statistically significant result.

    “We pushed to the limit what could be done within the time constraints,” said Friedman. “The experiment would not have been possible without an amazing international collaboration. It was a roller coaster experience to see it actually work.”

    The research was funded by the Austrian Academy of Sciences; The Austrian Science Fund with SFB F40 (FOQUS) and project COQuS (W1210-N16); the Austrian Federal Ministry of Education, Science and Research; the University of Vienna (via the project QUESS); the National Science Foundation INSPIRE Grant (PHY-1541160); the U.S. Department of Energy (DE-SC0012567); the U.S. Department of Defense, through the National Defense Science & Engineering Graduate Fellowship Program, and UC San Diego’s Ax Center for Experimental Cosmology.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    UC San Diego Campus

    The University of California, San Diego (also referred to as UC San Diego or UCSD), is a public research university located in the La Jolla area of San Diego, California, in the United States.[12] The university occupies 2,141 acres (866 ha) near the coast of the Pacific Ocean with the main campus resting on approximately 1,152 acres (466 ha).[13] Established in 1960 near the pre-existing Scripps Institution of Oceanography, UC San Diego is the seventh oldest of the 10 University of California campuses and offers over 200 undergraduate and graduate degree programs, enrolling about 22,700 undergraduate and 6,300 graduate students. UC San Diego is one of America’s Public Ivy universities, which recognizes top public research universities in the United States. UC San Diego was ranked 8th among public universities and 37th among all universities in the United States, and rated the 18th Top World University by U.S. News & World Report ‘s 2015 rankings.

     
  • richardmitnick 10:54 am on February 16, 2018 Permalink | Reply
    Tags: , , Study ocean currents and the tiny creatures they transport, Swarm of Underwater Robots Mimics Ocean Life, UCSD - University of Californa San Diego   

    From Scripps Institution of Oceanography: “Swarm of Underwater Robots Mimics Ocean Life” Jan 2017 

    Scripps Institution of Oceanography

    Jan 24, 2017 [Just found this]

    Mario Aguilera
    858-534-3624
    scrippsnews@ucsd.edu

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    Miniature autonomous underwater explorers.

    Underwater robots developed by researchers at Scripps Institution of Oceanography at the University of California San Diego offer scientists an extraordinary new tool to study ocean currents and the tiny creatures they transport. Swarms of these underwater robots helped answer some basic questions about the most abundant life forms in the ocean—plankton.

    Scripps research oceanographer Jules Jaffe designed and built the miniature autonomous underwater explorers, or M-AUEs, to study small-scale environmental processes taking place in the ocean. The ocean-probing instruments are equipped with temperature and other sensors to measure the surrounding ocean conditions while the robots “swim” up and down to maintain a constant depth by adjusting their buoyancy. The M-AUEs could potentially be deployed in swarms of hundreds to thousands to capture a three-dimensional view of the interactions between ocean currents and marine life.

    In a new study published in the Jan. 24 [2017] issue of the journal Nature Communications, Jaffe and Scripps biological oceanographer Peter Franks deployed a swarm of 16 grapefruit-sized underwater robots programmed to mimic the underwater swimming behavior of plankton, the microscopic organisms that drift with the ocean currents. The research study was designed to test theories about how plankton form dense patches under the ocean surface, which often later reveal themselves at the surface as red tides.

    “These patches might work like planktonic singles bars,” said Franks, who has long suspected that the dense aggregations could aid feeding, reproduction, and protection from predators.

    Two decades ago Franks published a mathematical theory predicting that swimming plankton would form dense patches when pushed around by internal waves—giant, slow-moving waves below the ocean surface. Testing his theory would require tracking the movements of individual plankton—each smaller than a grain of rice—as they swam in the ocean, which is not possible using available technology.

    Jaffe instead invented “robotic plankton” that drift with the ocean currents, but are programmed to move up and down by adjusting their buoyancy, imitating the movements of plankton. A swarm of these robotic plankton was the ideal tool to finally put Franks’ mathematical theory to the test.

    “The big engineering breakthroughs were to make the M-AUEs small, inexpensive, and able to be tracked continuously underwater,” said Jaffe. The low cost allowed Jaffe and his team to build a small army of the robots that could be deployed in a swarm.

    Tracking the individual M-AUEs was a challenge, as GPS does not work underwater. A key component of the project was the development by researchers at UC San Diego’s Qualcomm Institute and Department of Computer Science and Engineering of mathematical techniques to use acoustic signals to track the M-AUE vehicles while they were submerged.

    During a five-hour experiment, the Scripps researchers along with UC San Diego colleagues deployed a 300-meter (984-foot) diameter swarm of 16 M-AUEs programmed to stay 10-meters (33-feet) deep in the ocean off the coast of Torrey Pines, near La Jolla, Calif. The M-AUEs constantly adjusted their buoyancy to move vertically against the currents created by the internal waves. The three-dimensional location information collected every 12 seconds revealed where this robotic swarm moved below the ocean surface.

    The results of the study were nearly identical to what Franks predicted. The surrounding ocean temperatures fluctuated as the internal waves passed through the M-AUE swarm. And, as predicted by Franks, the M-AUE location data showed that the swarm formed a tightly packed patch in the warm waters of the internal wave troughs, but dispersed over the wave crests.

    “This is the first time such a mechanism has been tested underwater,” said Franks.

    The experiment helped the researchers confirm that free-floating plankton can use the physical dynamics of the ocean—in this case internal waves—to increase their concentrations to congregate into swarms to fulfill their fundamental life needs.

    “This swarm-sensing approach opens up a whole new realm of ocean exploration,” said Jaffe. Augmenting the M-AUEs with cameras would allow the photographic mapping of coral habitats, or “plankton selfies,” according to Jaffe.

    The research team has hopes to build hundreds more of the miniature robots to study the movement of larvae between marine protected areas, monitor harmful red tide blooms, and to help track oil spills. The onboard hydrophones that help track the M-AUEs underwater could also allow the swarm to act like a giant “ear” in the ocean, listening to and localizing ambient sounds in the ocean.

    Jaffe, Franks, and their colleagues were awarded nearly $1 million from the National Science Foundation in 2009 to develop and test the new breed of ocean-probing instruments. The study’s coauthors include: Paul Roberts, principal development engineer at Scripps, Ryan Kastner, professor in the Department of Computer Science and Engineering; Diba Mirza, postdoctoral researcher in computer science; and Curt Schurgers, principal development engineer at the Qualcomm Institute, and Scripps student intern Adrien Boch.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    A department of UC San Diego, Scripps Institution of Oceanography is one of the oldest, largest, and most important centers for ocean, earth and atmospheric science research, education, and public service in the world.

    Research at Scripps encompasses physical, chemical, biological, geological, and geophysical studies of the oceans, Earth, and planets. Scripps undergraduate and graduate programs provide transformative educational and research opportunities in ocean, earth, and atmospheric sciences, as well as degrees in climate science and policy and marine biodiversity and conservation.

     
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