2018 NHFP Fellows

Host Institution: Northwestern University

Proposal Title: Quantifying the Diversity of Relativistic Transients with Radio Observations

Kate Alexander grew up in New Jersey and California. She completed her bachelor’s degree in physics at Brown University in 2012 and will earn her PhD in astronomy and astrophysics from Harvard University in May 2018. At Harvard, Kate was an National Science Foundation Graduate Research Fellow and completed her thesis with Professor Edo Berger.

Kate’s research centers on astrophysical transients, including long and short gamma-ray bursts (GRBs) and tidal disruption events (TDEs) in which a star is torn apart by a supermassive black hole (SMBH). In particular, she studies the formation of relativistic jets and outflows with radio observations, which give the best constraints on the fastest-moving ejecta and the surrounding density. The advent of sensitive radio facilities like the Karl G. Jansky Very Large Array and the Atacama Large Millimeter/submillimeter Array (ALMA) in combination with deep all-sky optical surveys means that for the first time, it is possible to identify and study complete populations of relativistic transients, not just the brightest outliers. As an Einstein Fellow, Kate will leverage these new observational capabilities to place TDEs in the context of SMBH variability and growth, long GRBs in the context of stellar evolution, and short GRBs in the context of the first unbiased sample of binary neutron star mergers, provided by Advanced LIGO and Virgo.

Host Institution: Carnegie Observatories

Proposal Title: Driving the Growth of Joint Gravitational Wave and Electromagnetic Astronomy

Philip Cowperthwaite grew up in Maryland and received his undergraduate degrees in astronomy and physics from the University of Maryland, College Park in 2013. Philip then entered graduate studies at Harvard University as a National Science Foundation Graduate Research Fellow. Philip will earn his PhD in astronomy and astrophysics under the advisement of Professor Edo Berger.

Philip’s research focuses on planning and conducting electromagnetic follow-up of gravitational wave events discovered by the Advanced LIGO and Virgo interferometers. In particular, his work focuses on discovering and characterizing the optical transients that result from the merger of systems containing at least one neutron star, such as the kilonova associated with the binary neutron star merger GW170817. The modeling of such events provides unique insight into the merger dynamics, the production of r-process heavy elements in the universe, the neutron star equation of state, and even local cosmology. As a Hubble Fellow at the Carnegie Observatories, Philip will continue to follow up gravitational wave events discovered during future observing runs with Advanced LIGO and Virgo.

Host Institution: University of California, Berkeley

Proposal Title: A Uniform Measurement of Pre-Main Sequence Stellar Masses and System Architectures Using Protoplanetary Disks

Ian Czekala grew up on Long Island, New York. For his undergraduate studies, he attended the University of Virginia as a Jefferson Scholar, and graduated with bachelor’s degrees in aerospace engineering and astronomy. With the assistance of a National Science Foundation Graduate Fellowship, Ian completed his PhD at the Harvard-Smithsonian Center for Astrophysics, where he was advised by Sean Andrews. Ian’s thesis focused on understanding pre-main sequence stellar evolution by developing and applying novel inference techniques to high-resolution optical and infrared spectra and sub-millimeter interferometric datasets, with the goal of precisely measuring stellar masses. Accurate, empirical measurements of fundamental stellar properties (like mass) are key to understanding stellar evolution, but at young ages (< 10 Myr) are currently available for only a few dozen “benchmark” systems. Ian is currently a postdoctoral fellow at Stanford University’s Kavli Institute for Particle Astrophysics and Cosmology, where he works with Bruce Macintosh and the Gemini Planet Imager group to understand protoplanetary disk and stellar dynamics.

As a Sagan Fellow at University of California, Berkeley, Ian will work on expanding this benchmark sample of pre-main sequence stars by using the Atacama Large Millimeter/submillimeter Array (ALMA) to map the kinematics of a large sample of gas-rich protoplanetary disks. The protoplanetary disk-based dynamical mass technique directly yields precise measurements of the central stellar mass(es), avoids the error inherent to photospherically derived masses, and helps to resolve open questions about the processes that sculpt primordial material into solar systems. Ian will also use ALMA to directly probe the dynamically interesting circumstellar environments of pre-main sequence binary and triple stars to understand how stellar orbits impact the evolution of the protoplanetary disks in these systems and, ultimately, the planets that form within them.

Host Institution: Harvard University

Proposal Title: Mapping the True Boundary of Dark Matter Halos with the Splashback Radius

Benedikt Diemer grew up in Munich, Germany, but spent his undergraduate years at the University of Manchester and at University of California, Santa Barbara. After a brief stint in the software industry, he began his PhD at the University of Chicago under the supervision of Andrey Kravtsov. Since his graduation in 2015, he has been an Institute for Theory and Computation (ITC) fellow at Harvard University.

Benedikt is a computational astrophysicist with a diverse range of interests related to the formation of dark matter halos and galaxies, including large N-body simulations, halo structure, star formation, and magneto-hydrodynamics. His focus over the coming years will be to investigate and develop the splashback radius, a novel, physical definition of the boundary of dark matter halos. As a side project, Benedikt is part of the art and science collaboration “Fabric of the Universe,” where he explores artistic expressions of the cosmic web.

Host Institution: Stanford University

Proposal Title: The Highest-energy Electromagnetic Counterparts to Neutron Star Mergers

Ke Fang was born in Huangshan, China. She received her bachelor’s in physics from the University of Science and Technology of China. She received her PhD from the University of Chicago in 2015 and was advised by Angela V. Olinto. 

During her PhD, Ke focused on the role of newborn pulsars as sources of the highest-energy particles in the universe. As part of her thesis, she developed numerical techniques for simulating three-dimensional cosmic ray propagation and interaction in dense astrophysical environments. As an associated, full member of the GRAND, HAWC, IceCube, and JEM-EUSO collaborations, Ke’s current research contributes to understanding sources of astroparticles by taking three approaches: theoretical modeling, data analysis, and future experiments.. As an Einstein Fellow, she will work on building up the theory of cosmic ray sources using numerical tools, including studying astroparticle emission from compact objects and binary mergers. She will also analyze astroparticle data for point sources with an efficient source-finding algorithm she developed with a collaborator. Finally, she will continue to actively participate in developing the future ultrahigh-energy neutrino detector GRAND.

Host Institution: California Institute of Technology

Proposal Title: Putting a New Generation of Strongly Lensed Supernovae to Work

Danny Goldstein grew up in Bethesda, Maryland. In 2013, he graduated summa cum laude from the University of Pennsylvania, where he obtained a bachelor’s with distinction in physics and was inducted into Phi Beta Kappa. Danny received his PhD in astrophysics from the University of California, Berkeley in 2018, where he was advised by Peter Nugent and Dan Kasen.

Danny’s research focuses on strong gravitational lensing, cosmology, and the discovery, observation and theoretical modeling of astrophysical transients. As a Hubble Fellow, Danny will use the Zwicky Transient Facility to produce the first statistical sample of strongly gravitationally lensed supernovae. Arrival time delays between the multiple images of these systems will enable a precise, independent measurement of the Hubble constant, which is currently in tension, as well as an unprecedented look into the earliest moments of supernova explosions.

Host Institution: University of California, Santa Barbara

Proposal Title: Casting (Lyman-Alpha) Light on Galaxy Formation

Max Gronke grew up in Schramberg, a small town in the black forest area in Germany, and moved to Berlin for his undergraduate studies. For his graduate studies, Max moved north to Oslo, Norway, where he obtained his PhD from the Institute of Theoretical Astrophysics in 2017.

Max is a theorist with a broad range of interests ranging from modified gravity, over the epoch of reionization, to resonant line transfer, and small-scale (magneto) hydrodynamics. During his fellowship, Max hopes to work on problems that connect the latter two fields, in particular, to use the Lyman-alpha line of neutral hydrogen to learn more about gas dynamics in and around high-redshift galaxies.

Host Institution: Massachusetts Institute of Technology

Proposal Title: Fundamental Physics in the Era of Gravitational Wave Astronomy

Maximiliano Isi was born and raised in Montevideo, Uruguay, where he lived until moving to Los Angeles for university in 2010. Four years later, Max received his bachelor’s degree summa cum laude in physics and applied mathematics from Loyola Marymount University. He is currently finishing his PhD in Physics at the California Institute of Technology, where he is part of Alan Weinstein’s LIGO Laboratory Astrophysics group.

Max specializes in the phenomenological study of the basic properties of gravitational waves to learn about gravity in its most interesting, highly dynamic regime. This includes the analysis of past and future detections from compact-binary coalescences, as well as the development of methods and theoretical work for the study of persistent, almost-monochromatic signals and stochastic backgrounds. As an Einstein Fellow at the Massachusetts Institute of Technology, he will develop novel techniques to extract fundamental physics and astrophysics from gravitational waves in the new and exciting era of multi-messenger astronomy, using present and future detectors. This will include measuring the polarization of gravitational waves, studying their propagation properties (speed and dispersion), and using rigorous statistics to learn from large numbers of detections.

Host Institution: Arizona State University

Proposal Title: How do Substellar Objects Generate Magnetic Fields?

Melodie Kao grew up in North Carolina, Connecticut, and Illinois before returning to New England to receive her bachelor’s in physics from the Massachusetts Institute of Technology in 2011. As a graduate student, Melodie held a National Radio Astronomy Observatory (NRAO) Grote Reber Doctoral Fellowship at the NRAO in Socorro, New Mexico. In June 2017, she earned her PhD in astrophysics from the California Institute of Technology, where she was advised by Gregg Hallinan. 

Melodie’s dissertation research focused on developing brown dwarf radio emission into a viable tool for measuring the magnetic fields of very cold brown dwarfs. She is very interested in brown dwarf magnetic fields because the magnetic dynamo mechanisms occurring in brown dwarfs can also occur in low mass stars, gas giant planets, and even terrestrial planets. The magnetic fields generated by these dynamo mechanisms play a pervasive role in planetary systems, impacting interior structure, atmospheric evolution, and habitability. As a Hubble Fellow at Arizona State University, Melodie will harness the methods she developed during graduate school to characterize the magnetic fields of very cold brown dwarfs with the goal of understanding the physical processes that generate the magnetic fields in the mass regime bridging planets and stars.

Host Institution: University of California, Berkeley

Proposal Title: Interpreting the Diverse Transient Sky

Ben Margalit was born in California, but spent most of his life in northern Israel and Jerusalem. He obtained his bachelor’s and master’s degrees at the Hebrew University of Jerusalem. Ben will earn a PhD from Columbia University in summer 2018.

In his research, Ben uses analytic and numerical tools to model and interpret transient astrophysical phenomena ranging from kilonovae to peculiar supernovae, fast radio bursts, and gamma-ray bursts. He is particularly interested in the electromagnetic signatures resulting from the merger of compact objects such as neutron stars and white dwarfs. These events have outstanding astrophysical implications and provide a unique probe of fundamental physics such as the (uncertain) equation of state of dense nuclear matter. 

As an Einstein Fellow, Ben will continue studying compact object mergers, exploring the increasing wealth of information that can be extracted from upcoming neutron star merger observations, while looking toward the future of multi-messenger astronomy by modelling white dwarf neutron star mergers.

Host Institution: Smithsonian Astrophysical Observatory

Proposal Title: Revolutionizing Reionization with JWST

Charlotte Mason grew up near Oxford, England. She earned an undergraduate degree in physics from the University of Oxford in 2013 and a master’s in physics from the University of California, Santa Barbara in 2015. She will complete her PhD at UCLA spring 2018, advised by Tommaso Treu. Her PhD was supported by a NASA Earth and Space Science Fellowship.

Charlotte’s research focuses on the evolution of galaxies in the early universe, and the reionization of intergalactic hydrogen in the first billion years, processes that set the stage for the modern universe. However, the very first stars and galaxies are too faint to detect directly so we need ways to infer their properties. Charlotte combines empirical and semi-analytical modelling with statistical analyses of observations to ask what galaxies at our current frontiers can tell us about star formation and physical conditions in the early universe. As a Hubble Fellow at the Harvard-Smithsonian Center for Astrophysics, Charlotte will develop new modelling frameworks required to interpret upcoming observations with NASA’s James Webb Space Telescope to better understand when and how cosmic reionization happened, and how galaxies formed and evolved in the universe’s first billion years.

Host Institution: Jet Propulsion Laboratory

Proposal Title: Can We Detect Exo-Earths with Future Large Space-Based Coronagraphic Instruments?

Johan Mazoyer was born in Paris, France, and spent most of his life there. He received his bachelor’s in 2010 from École Polytechnique and his PhD at Université Paris Diderot in 2014. After the completion of his thesis, Johan spent three years in Baltimore, Maryland, as a postdoctoral fellow at the Space Telescope Science Institute and Johns Hopkins University. 

As a student, he hesitated for a long time between space system engineering and astronomy, between building objects that go to outer space or studying it directly. After getting a master in each of these fields, Johan decided to work in the field of astronomical instrumentation, specifically for exoplanets, which allows him to combine these two passions: building the most challenging space instruments to observe distant worlds.

He intends to pursue this dual interest in space instrumentation and exoplanets as a Sagan Fellow at the Jet Propulsion Laboratory. Both as an observer and as an instrumentalist, Johan will investigate crucial limitations that have to be studied and understood long before the development of the next generation of space telescopes for the imaging and characterization of exo-Earths. He will first study exozodis using interferometry and NASA’s James Webb Space Telescope to understand if this hot dust can be the ultimate limitation to the detection of planets in the innermost part of the stellar systems. He will also develop innovative, active methods on the Jet Propulsion Laboratory’s testbeds to increase the yield of exoplanets analyzed and discovered by the next generation of space-based telescopes.

Host Institution: California Institute of Technology

Proposal Title: Revealing the Sun's Coolest, Nearest Neighbors with NEOWISE-Reactivation

Aaron Meisner grew up in Bellevue, Washington. He majored in physics at Stanford University, graduating in 2010. He completed his PhD in physics at Harvard University in 2015, supported by National Science Foundation and National Defense Science and Engineering graduate research fellowships. Following that, he was a postdoctoral fellow at the Berkeley Center for Cosmological Physics.

Aaron specializes in making and analyzing full-sky, high-resolution maps based on large data sets from wide-area astronomical surveys. He has been leading an ambitious effort to reprocess millions of images from NASA’s asteroid-hunting NEOWISE mission, unlocking the full value of this vast data set for astrophysics beyond the inner solar system. Through this work, he co-founded the popular Backyard Worlds citizen science project, while also playing a key role in wide-area imaging surveys that will enable the upcoming Dark Energy Spectroscopic Instrument (DESI). As a Hubble Fellow, Aaron will leverage NEOWISE data to discover extremely cold brown dwarfs in the solar neighborhood, improving our understanding of the galactic substellar population and identifying nearby giant exoplanet analogs.

Host Institution: Harvard University

Proposal Title: The Emergence of Galactic Structure

Born and raised in Minneapolis, Minnesota, Erica Nelson is a proud product of the Minneapolis public school system and as well as Pomona College in Claremont, California. After completing her PhD at Yale University in 2016, she was a postdoctoral fellow at the Max Planck Institut für Extraterrestrische Physik in Munich.

Erica’s research program focuses on understanding the emergence of galactic structure: how the universe evolved from its uniform state shortly after the big bang to the rich diversity of galaxies today. Using grism spectroscopy with NASA’s Hubble Space Telescope, she pioneered a new method to directly image emerging galactic structure in the distant past. Because a significant fraction of all star formation occurs in optically thick regimes, Erica is currently leading a program to probe dust-obscured bulge building using millimeter interferometry. With the launch of NASA’s James Webb Space Telescope, in conjunction with state-of-the-art cosmological hydrodynamical simulations, she is excited to uncover the physical processes that drive the structural and kinematic evolution of early galaxies.

Host Institution: California Institute of Technology

Proposal Title: The Origin of Small Planets

Erik Petigura grew up in Palo Alto, California. When he was about 5 years old, he watched Carl Sagan’s “Cosmos,” which inspired a lifelong passion for science and astronomy. Erik received his PhD from the University of California, Berkeley in 2015. His thesis focused on measuring the prevalence of planets as small as Earth using NASA’s Kepler mission. This work helped to constrain the frequency of planets similar to Earth in size and temperature.

One of the biggest surprises from Kepler was that nearly every Sun-like star has a planet larger than Earth but smaller than Neptune. Given the lack of such planets orbiting the Sun, Kepler has demonstrated that the Solar System is not a typical outcome of planet formation, in at least that respect. Therefore, in the post-Kepler era, we are compelled to ask: “Why does nature produce super-Earths and sub-Neptunes so efficiently?” and “Why do we lack such planets in our own Solar System?”

As a Sagan Fellow at the California Institute of Technology, Erik will work to understand the origin of super-Earths and sub-Neptunes through observational surveys that leverage the large collecting area and unique instrument capabilities of the 10-meter W. M. Keck Observatory telescopes. He will investigate how rocky cores are assembled, why some planets manage to acquire and retain gaseous envelopes, and how often planetary systems undergo violent episodes of mergers and ejections.

Host Institution: University of Texas at Austin

Proposal Title: Minihaloes: Formation Sites of the First Stars and the Onset of Reionization

Anna T. P. Schauer grew up in Munich, Germany, where she completed her bachelor’s in physics in 2012 and two masters’ degrees in physics and astrophysics in 2014. For her PhD, she moved to Universität Heidelberg. She defended her PhD thesis in October 2017 and will move as a Hubble Fellow to the University of Texas at Austin in fall 2018.

Anna’s research focuses on the formation of the first stars. With hydrodynamic simulations, she studies large-scale effects that influence the early building blocks of galaxies: minihaloes. By investigating these first objects, she aims to understand how the universe underwent the transition from metal-free to metal-enriched. As a Hubble Fellow, one of Anna’s goals is to study the combined effect of the large-scale Lyman-Werner radiation field and the relative motion of baryons and dark matter imprinted from recombination, which both delay the formation of the first stars. She will further investigate how the ionizing radiation of these first stars and the spread of metals from the subsequent supernovae can enrich the environment.

Host Institution: University of Arizona

Proposal Title: The Evolution of Volatile Molecules from Protoplanetary Disks to Exoplanet Atmospheres

Kamber Schwarz grew up Hereford, Arizona, and received her bachelor’s in astronomy and physics from the University of Arizona in 2012. She will earn her PhD in astronomy and astrophysics from the University of Michigan in summer 2018. Her research combines millimeter and sub-millimeter observations with chemical modeling to study the molecular content and physical properties of protoplanetary disks. During her PhD research, her work has focused on characterizing the abundance of volatile molecular gas in disks. Moving forward, Kamber is interested in constraining the timescales and mechanisms for the reprocessing of volatile molecules, with the goal of determining the amount of volatile carbon, nitrogen, and oxygen available to forming planets.

Host Institution: University of Arizona

Proposal Title: Unveiling the Obscured Early Universe in the JWST Era

Irene Shivaei was born and raised in Tehran, Iran. Influenced by astronomy teachers during high school, she was first an amateur astronomer before entering university to pursue professional astronomy. In 2011, she received her bachelor’s degree in physics from the University of Tehran, and moved to the U.S. to continue her graduate studies at the University of California, Riverside. She received a National Science Foundation Graduate Research Fellowship in 2013 and graduated with a PhD in physics in July 2017 under the supervision of Dr. Naveen Reddy. Her thesis is titled “A multi-wavelength spectroscopic and photometric study of star formation and dust in galaxies in the early universe.” In September 2017, Irene started a postdoctoral researcher position for NASA’s James Webb Space Telescope (JWST) MIRI and NIRCam teams at the University of Arizona.

Most of her graduate work was part of the MOSDEF survey to use MOSFIRE multi-object near-infrared spectrograph on the W. M. Keck Observatory’s Keck I telescope to study galaxies at the peak epoch of star formation activity in the universe (z~1.5-3.5). By incorporating NASA’s Spitzer and the European Space Agency’s Herschel Space Observatory infrared data, Irene focused on determining accurate star formation rates, the behavior of mid-infrared aromatic features (commonly described as PAH molecules) with interstellar medium (ISM) excitation properties, and ionizing photon production efficiencies at z~2. 

As a Hubble Fellow at the University of Arizona and a member of the JWST MIRI and NIRCam GTO extragalactic science teams, she plans to study the characteristics of dust and obscured star-forming regions at high redshifts. Studying dust absorption and emission features reveals valuable information about the ISM conditions and stellar populations of high-redshift galaxies, and enhances our understanding of galaxy formation and evolution throughout cosmic time. Besides research, she enjoys outreach activities. In 2014, she and a colleague started an astrobites sister website in Persian (www.staryab.com), which reflects recent astronomy literature for undergraduate students on a weekly basis. In the fall of 2017, she established the MESCIT mentorship program for Native American high school students in Tucson, Arizona.

Host Institution: Massachusetts Institute of Technology

Proposal Title: Radiation Signatures of the First Galaxies and Supermassive Black Holes

Aaron Smith grew up in the mountains of San Diego, California, and received bachelor degrees in physics and mathematics from Brigham Young University. He was awarded a National Science Foundation Graduate Research Fellowship to study theoretical astrophysics with Volker Bromm at the University of Texas at Austin. He will finish his PhD in summer 2018 and continue his research as an Einstein Fellow at the Massachusetts Institute of Technology.

Aaron’s dissertation focused on modeling the Lyman-alpha line of atomic hydrogen, which is a powerful probe of the high-redshift universe due to its characteristic strength and spectral properties. He has developed novel methods to significantly accelerate Lyman-alpha simulations, so that full three-dimensional radiation hydrodynamical coupling for resonance lines becomes feasible. As an Einstein Fellow, he will apply multiple state-of-the-art radiative transfer schemes to a wide range of astrophysical settings, including high-resolution cosmological simulations to illuminate the galaxy and supermassive black hole formation process.

Host Institution: Ohio State University

Proposal Title: Core-Collapse Supernovae across Metallicities and Engines

Tuguldur Sukhbold was born and raised in Mongolia. In 2007, he moved to U.S. to pursue his education in astrophysics. He received his bachelor’s degree from the University of Arizona in 2011, and his PhD from University of California Santa Cruz in 2016, working with Stan Woosley. After completing his thesis, Tuguldur became a Center for Cosmology and AstroParticle Physics (CCAPP) fellow at Ohio State University.

While he had a keen interest in science from a young age, Tuguldur decided to become a scientist after pondering existential questions as a teenager. He figured life is worth living only if he spends it trying to understand our utterly mysterious universe.

Tuguldur is interested in theoretical and computational high-energy astrophysics, with an emphasis on massive stars and supernovae. As a Hubble Fellow, he plans to investigate the evolution and explosion of massive stars through numerical and semi-analytical tools to improve our understanding of the origin of heavy elements, compact objects and the mechanism of core-collapse supernova explosions. This work will lay the theoretical groundwork for the interpretation of diverse results expected from various current and upcoming instruments such as the Large Synoptic Survey Telescope (LSST), the Zwicky Transient Facility, NASA’s James Webb Space Telescope, and the Laser Interferometer Gravitational-Wave Observatory (LIGO).

Host Institution: Princeton University

Proposal Title: A Million-Fold Speedup in the Dynamical Characterization of Exoplanet Systems

Daniel Tamayo grew up in Spain and Michigan, where he majored in physics, mathematics, and philosophy at the University of Michigan. He then served two years with the Peace Corps in Otjimbingwe, a small village in Namibia, teaching mathematics and physical science. He earned his PhD from Cornell University in 2015, working with Joe Burns and Phil Nicholson.

Dan’s graduate work focused on observational and dynamical modeling of collisional debris from irregular satellites around giant planets. The material from these gravitationally captured remnants from the era of planet formation have dramatically altered the surfaces of the icy satellites closer to their host planets. His current work focuses on the dynamics of exoplanets, developing numerical and analytical approaches to understand this quickly growing population. As a Sagan Fellow, Dan will work on combining analytical and machine learning techniques to predict instability timescales in chaotic planetary systems to both help characterize new discoveries and to elucidate how orbital architectures change over billions of years of evolution.

Host Institution: University of Hawaii

Proposal Title: Subgiants: Models, Rotation, Convection, and Planets

Jamie Tayar grew up in Florida and earned a bachelor’s degree in astrophysics from the California Institute of Technology. She will earn her PhD in Astronomy from Ohio State University in summer 2018.

Jamie’s research focuses on using a combination of observational data and stellar evolution models to better understand the structure and evolution of evolved stars. She has identified important differences between the predictions of stellar models and the available data, and worked to find ways to reconcile the two. She has also been particularly interested in what the core and surface rotation rates of red giants can tell us about angular momentum transport and loss. As a Hubble Fellow, Jamie plans to combine asteroseismic and spectroscopic measurements of subgiants in the Transiting Exoplanet Survey Satellite (TESS) continuous viewing zones to calibrate stellar models, and better understand the rotational evolution of low-mass stars and the properties of their convection.

Host Institution: Institute for Advanced Study

Proposal Title: Chemically Tagging the Milky Way

Yuan-Sen Ting grew up in the beautiful country of Malaysia. His father’s broad interest in reading piqued his interest in interdisciplinary science at a very young age. As an undergraduate, he went through a concurrent double degree program from Singapore and France. He received his bachelor’s and master’s degrees in physics from the National University of Singapore and an engineer’s degree (Diplôme d'Ingénieur) from École Polytechnique in Paris, France. He received his PhD in astrophysics in 2017 from Harvard University funded through a NASA Earth and Space Science Fellowship and under the guidance of Professor Charlie Conroy. He is currently jointly affiliated with the Institute for Advanced Study, Princeton University, and the Carnegie Observatories.

Yuan-Sen’s research operates at the cross-section between theoretical modeling, observational astronomy, machine learning and statistical tools to unravel the history of the Milky Way. In particular, he is developing tools to maximally extract information from the vastly abundant low-resolution spectra and to implement the powerful concept known as chemical tagging. Like twins separated at birth, stars in the Milky Way are torn apart after they form. Yuan-Sen aims to use their chemical fingerprints to reconstruct the origins of individual stars, unwinding the cosmic clock. In addition to shedding light on star formation, this research will reveal the dynamic and chemical history of the Milky Way, and has motivated the collection of a large amount of data from billions of stars in the Milky Way. Yuan-Sen hopes to help realize the total potential of these large surveys through his statistical and machine learning skills, and bring the full life cycle of the Milky Way into greater focus.

Host Institution: Princeton University

Proposal Title: First-Principles Modeling of Astrophysical Turbulence in Collisionless, Nonthermal Plasmas

Vladimir Zhdankin was raised by chemists in Duluth, Minnesota. He completed his bachelor’s and PhD in physics in 2015 at the University of Wisconsin–Madison. He has been a postdoctoral research associate at JILA at the University of Colorado at Boulder for three years.

Vladimir’s research is focused on theoretical high-energy astrophysics. He is interested in understanding the role of nonlinear plasma physical processes, such as turbulence, magnetic reconnection, and shocks, in a variety of systems. His work has involved developing numerical methods to study dissipative events in magnetohydrodynamic turbulence and performing kinetic “particle-in-cell” simulations to study nonthermal particle acceleration in relativistic plasmas (similar to those in pulsar wind nebulae and jets of active galactic nuclei). As an Einstein Fellow at Princeton University, Vladimir will apply kinetic simulations and analytic theory to investigate the properties of turbulence in collisionless plasmas consisting of sub-relativistic ions and relativistic electrons (which emit synchrotron and inverse Compton radiation), with applications for hot accretion flows around black holes and for cosmic ray acceleration.

➤ Last updated: April 4, 2019