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Astrophysics Notre Dame’S Partnership in the Large Binocular Telescope NOTRE DAME ASTROPHYSICS NOTRE DAME’S PARTNERSHIP IN THE LARGE BINOCULAR TELESCOPE The Large Binocular Telescope (LBT) stands on carbon and oxygen are created, and the LBT will Mt. Graham in Arizona, at 10,700 feet above sea support our quest for understanding. level, and next to the 1.8-m Vatican Advanced Technology Telescope. The unique facility is Telescopes not only look at distant objects, actually two 8.4-m telescopes that act in tandem but also act as time machines. Because light to produce images unlike any seen before. The may travel for billions of years before being LBT has the equivalent collecting power of a captured by the LBT’s mirrors, the images 12-m and the resolution of a 22-m telescope, far reveal the Universe as it was long ago. One of better than any other telescope today. It is the the big mysteries uncovered by the Hubble forerunner of the next generation of ultra-large Space Telescope program is the existence of telescopes. fully formed galaxies in the early universe, much earlier than physicists predicted. Their formation The LBT has extraordinary capabilities. will be a key research program for the LBT and Its design allows it to directly observe distant Origins Institute faculty Dinshaw Balsara and stars systems and to actually see planets in the Christopher Howk, who aim to understand the systems. Its ability to measure very precise atomic dynamics that govern the formation of galaxies spectra even enables researchers to determine the and with them the beginnings of life. chemical makeup of the planets’ atmospheres. Exploiting the LBT’s unique design, Justin With a total cost of $200 million, the LBT Crepp is currently building a novel spectrometer is one of the world’s greatest observatories. Its that will detect the small wobble of an Earth-size suite of instruments allows for versatility and planet in the habitable zone of a cool star. the ability to study an extremely wide range of astrophysical research topics. The LBT has the Notre Dame faculty are using the LBT world’s best adaptive optics (AO) system, which to study distant supernovae so they can better reduces the blur caused by the Earth’s atmosphere understand the nature of dark energy. These to the point that LBT imaging rivals that of the same exploding stars are the fiery furnaces that Hubble Space Telescope. Soon, a state-of-the-art produce most of the elements that make up laser guide star system will form points of light in our bodies. We have incomplete knowledge of the upper atmosphere to allow the AO system to how such simple and important elements as work anywhere on the sky. 1 Fig. 1 Fig. 2 CONTENTS DINSHAW BALSARA Associate Professor Notre Dame’s Partnership in the Large Binocular Concurrent Associate Professor, Applied and Computational Mathematics and Statistics Telescope ......................................................................... 1 Dinshaw Balsara ............................................................. 3 Timothy Beers ................................................................ 4 M.S. in Physics, Indian Inst. of Tech., relativistic astrophysics and he continues to insights into the nature of the multi-phase Justin Crepp .................................................................... 5 Kanpur, 1982 work in all of those areas of research. ISM and the evolution of magnetic fields in M.S. in Astronomy, University of Chicago, Balsara has also played a seminal role it. Keith Davis ..................................................................... 6 1989 in formulating our modern conception of Star formation in turbulent, magnetized Ph.D. in Computational Astrophysics, computational astrophysics. His work on environments has also been a topic of Peter Garnavich ............................................................... 7 Univ. of Illinois at Urbana-Champaign, divergence-free adaptive mesh refinement significant recent focus. Balsara’s theories J. Christopher Howk ....................................................... 8 1990 for magnetohydrodynamics (MHD) has and simulations of two-fluid magnetized broken new ground for our understanding of turbulence have been used to decipher the Nicolas Lehner ................................................................ 9 Defense Department Award of Excellence numerical MHD. He has also produced some role of ambipolar diffusion in star formation. for significant contributions to the of the best, most accurate and most robust Fig. 2 shows linewidth-size relations from Grant Mathews .............................................................. 10 Stockpile Stewardship Program, 2014 methods for numerical MHD and has recently observations and Balsara’s simulations, Lara Phillips .................................................................. 11 begun extending this expertise to radiative indicating a good match between the two. Balsara has a dual training in physics and transfer as well as non-ideal processes that are The dynamics of dust and its role Vinicius Placco .............................................................. 12 astrophysics. After earning a Ph.D. in often very useful in regulating astrophysical in building planets within turbulent, computational astrophysics, he subsequently phenomena. Several of Balsara’s papers have magnetized, protostellar accretion disks has Terrence Rettig .............................................................. 13 worked on several problems in active galactic been cited over a hundred times. also been a topic of recent study. In-Saeng Suh ................................................................. 14 nuclei, studying the accretion on to black The above-mentioned numerical expertise Balsara also has a significant scientific holes and compact objects, starburst galaxies is routinely applied to problems in all areas interest in PetaScale and ExaScale computing Rebecca Surman ............................................................ 15 and galaxies in clusters. More recently, he of computational astrophysics. In fact, the and has worked with some of the world’s fastest has developed computational applications in robust numerics was central to the process of supercomputers. He serves on the editorial Digital Visualization Theater ........................................ 16 the areas of interstellar medium, turbulence, carrying out path-breaking simulations of the boards of the Journal of Computational Physics star formation, planet formation, the physics supernova explosion-driven ISM turbulence, and also Computational Astrophysics and of accretion disks, compact objects and Fig. 1. That work has resulted in many new Cosmology. 2 3 Fig 1: BD+44:493, the brightest CEMP star in the sky, discovered by Beers and his colleagues. This star has been observed using the world’s largest telescopes, as well as the Hubble Space Telescope, to provide measures of the elemental abundance patterns produced by the very first stars in the Universe. TIMOTHY BEERS JUSTIN CREPP Notre Dame Chair of Astrophysics Freimann Assistant Professor B.S. in Physics, Purdue University, 1979 thorium and uranium, used to establish a nuclear- His work has led to: B.S. in Metallurgical Engineering, Purdue decay lower limit on the age of the Universe. University, 1979 • The discovery of over 30,000 stars in the Galaxy Beers now leads the involvement of Notre Ph.D. in Astronomy, Harvard University, with heavy-element abundances less than 1 percent Dame astronomers in SDSS-IV, the third B.S. in Physics, Penn State, 2003 80 exoplanets, including the first one found planet-finding spectrometer is being built for 1983 of the metal abundance of the Sun, including the extension of the Sloan Digital Sky Survey. Beers’ Ph.D. in Physics, University of Florida, in the habitable zone. Crepp was named to the Large Binocular Telescope in Arizona. most chemically primitive stars yet found. These particular interest in SDSS-IV is the APOGEE- 2008 NASA’s Transiting Exoplanet Survey Satellite The work is searching for the presence of life Bantrell Postdoctoral Fellow, Caltech ancient stars are the “fossils of creation” that have II project, which is obtaining high-resolution (TESS) science team in 2014. elsewhere in the universe. Humboldt Senior Research Award, 2009 recorded the chemical history of the Universe. near-infrared spectroscopy of several hundred Justin Crepp, the Frank M. Freimann Crepp designs and builds instruments Crepp also leads a new observing program Director, Kitt Peak National Observatory, thousand stars in the Milky Way. These stars with Assistant Professor of Physics, is an that operate at visible and near-infrared called TRENDS that combines the Doppler University Distinguished Professor • The discovery of carbon-enhanced metal-poor help constrain the chemical evolution of all of the experimental astrophysicist. His research wavelengths to directly image and study method with high-contrast imaging to yield Emeritus, Michigan State University (CEMP) stars, whose properties are revealing the stellar populations in our Galaxy, including the involves developing new technologies to brown dwarfs and extrasolar planets. He highly accurate measures of the mass of Fellow of the American Physical Society origin of the first elements heavier than helium in thin disk, the thick disk, the bulge, and the inner detect and study planets orbiting stars other also uses the Doppler method to measure objects orbiting stars. In 2016, his laboratory the Universe. These stars include objects shown and outer halo. than the Sun, called “exoplanets.”
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