Research Programs and Observing Facilities

From the mountains of Chile to the glaciers of the South Pole, Ohio State astronomy faculty travel the world as they work at the cutting edge of astronomical research. The research themes and interests of the faculty overlap considerably, providing an opportunity for students and postdocs to work closely with a variety of experts in many areas.

The main research programs of the department are:

Research Programs

Extrasolar Planetary Systems

Artists depiction of extrasolar planetary system HD70642Observational searches for extrasolar planets using gravitational microlensing, and cluster and field star transit surveys. Observational and theoretical studies of the demographics of planetary systems, and the possible linkages with the systematic properties like age and metallicity of the host stars of planetary systems. Follow-up studies of transiting planet systems, and surveys for new extra-solar planets as part of the SDSS-III Collaboration.

Affiliated Faculty: Scott Gaudi, Andrew Gould, Richard Pogge

Stellar Structure & Evolution

GONG rendering of solar oscillationsTheoretical and observational studies of the structure and evolution of stars, with applications that include helioseismology, the solar neutrino problem, the influence of stellar nucleosynthesis on chemical abundances, the properties of star clusters, and the measurement of fundamental stellar properties (mass, radius, rotation and activity, etc.)

Affiliated Faculty: Jennifer Johnson, Marc Pinsonneault, Donald Terndrup

Star Formation & Interstellar Chemistry

TIFKAM near-infrared image of Galactic star forming region W3Theoretical, observational, and experimental studies of molecules and dust grains in interstellar and circumstellar environments, with attention to formation processes and diagnostics of physical conditions. Includes observational and theoretical investigations of interstellar gas and dust in the Milky Way and other galaxies, and the use of optical, and especially infrared observations to probe star formation activity.

Affiliated Faculty: Adam Leroy, Laura Lopez


Supernovae, Gamma-Ray Bursts & Compact Objects

Crab Nebula taken with MODS1 on the LBTObservational studies of core-collapse supernovae, Type-Ia supernovae (the thermonuclear detonation of carbon-oxygen white dwarfs),  gamma-ray bursts, new and exotic transients, their progenitors, and their evolving remnants.  Theoretical investigations of the mechanism of core-collapse supernovae, the birth of neutron stars, neutrino physics, nucleosynthesis of the heavy elements, mass loss from their progenitors, thermal and non-thermal emission from their blast waves, and the engine of gamma-ray bursts, including relativistic winds from newborn rapidly rotating magnetars. Population studies, census, and demographics of compact objects, supernovae, and progenitors.

Affiliated Faculty: John Beacom, Christopher Kochanek, Laura Lopez, Krzysztof Stanek, Todd Thompson

Galactic Structure

Near-infrared image of the Galactic Center taken with OSIRISObservational investigations of the stellar contents, chemical abundances, and dynamics of the Galactic Center. Observational studies of the stellar populations of the bulge, disk, and halo of the Milky Way, and interpretation of observational data in light of dynamical models. Analysis of Galactic structure using SDSS-II and SDSS-III data (SEGUE and APOGEE).

Affiliated Faculty: Jennifer Johnson, Donald Terndrup, David Weinberg

 

Gravitational Lensing and Microlensing

Hubble H-band image of the gravitationally lensed quasar PG1115Theoretical and observational studies of gravitational lensing from scales ranging from microlensing due to stars to strong lensing due to clusters of galaxies, with applications for determining the nature of dark matter, measuring limb darkening in stellar atmospheres, probing the structures of quasars and dark-matter halos, and searching for extra-solar planets using gravitational microlensing.

Affiliated Faculty: Scott Gaudi, Andrew Gould, Christopher Kochanek, Richard Pogge

 

Galaxy Formation & Evolution

OSU bright galaxy survey color composite image of the Antennae interactive galaxy pairObservational studies of the structure and stellar content of external galaxies, from the Local Group to young galaxies at cosmological distances. Modeling of the dynamics and shapes of different types of galaxies. Theoretical investigations of galaxy formation and galaxy transformations (e.g., via major or minor mergers), using analytic methods and numerical simulations on supercomputers.

Affiliated Faculty: Adam Leroy, Laura Lopez, Paul Martini, Annika Peter, Richard Pogge, Todd Thompson, David Weinberg

 

Active Galactic Nuclei & Quasars

Hubble image of the center of M87 showing the active nucleus and jetTime-series analysis of multiwavelength monitoring campaigns, to constrain the sizes, structures, and central black hole masses of active galaxies and quasars, investigations of the causes of nuclear activity and the physical state of active nuclei using optical, infrared, ultraviolet, and X-ray imaging and spectroscopy. Surveys for high-redshift quasars and the evolution of the cosmic quasar population, and observational studies of accretion and outflow phenomena in active galaxies. Work on active galaxies is carried out using ground-based telescopes, the Hubble Space Telescope, and various orbiting observatories including the Chandra and XMM/Newton X-ray observatory.

Affiliated Faculty: Christopher Kochanek, Paul Martini, Smita Mathur, Patrick Osmer, Bradley Peterson, 

Cosmology & Large-Scale Structure

N-body simulation of large-scale structure formationObservational studies of the cosmic distance scale and the high-redshift universe. Theoretical studies of Big Bang nucleosynthesis, the cosmic microwave background, large-scale structure, and the intergalactic medium, with goals that include testing the standard models of particle physics and cosmology, determining the baryon content of the universe and other fundamental cosmological parameters, and providing a theoretical framework for interpreting the observed evolution and clustering of galaxies, quasars, and quasar absorption-line systems at UV, visible, and X-ray wavelengths. Analysis of large-scale structure and galaxy and quasar properties in the Sloan Digital Sky Survey (SDSS), Dark Energy Survey (DES), and Dark Energy Spectroscopic Instrument (DESI). 

Affiliated Faculty: Chris Hirata, Paul Martini, Barbara Ryden, Annika Peter, Gary Steigman, David Weinberg

Astronomical Instrumentation

Computer rendering of the MODS spectrograph for the LBTOSU is one of the world's leading centers for the design and construction of advanced, state-of-the-art optical and infrared instruments for small and large telescopes, instrument control and detector systems, and large-mirror coating systems. Since 1990, we have deployed more than a dozen instruments at observatories on six continents, most of which are still in active research use.

Affiliated Faculty: Paul Martini, Richard Pogge

 

Nuclear & Particle Astrophysics

Graph showing big-bang nucleosynthesis yieldsTheoretical and experimental investigations of astrophysically important nuclear and particle processes, with applications that include stellar and Big Bang nucleosynthesis, solar neutrinos, interactions of cosmic rays with the cosmic background radiation, the nature of particle dark matter, and the emission and detection of neutrinos from supernovae.

Affiliated Faculty: John Beacom, Jim Beatty, Annika Peter, Todd Thompson

 

Atomic Astrophysics

Theoretical calculations and measurement of Fe++ cross-sectionsTheoretical studies of atomic physics and spectral-line formation in astrophysical environments such as gaseous nebulae, stellar atmospheres and interiors, supernovae, and active galactic nuclei. Work at OSU is focused on the precise calculation of atomic parameters using large-scale quantum mechanical calculations carried out at the Ohio Supercomputer Center. Prof. Anil Pradhan and his group are members of the international collaboration to compute fundamental atomic parameters (excitation, photoionization, and recombination) for all iron-peak elements.

Affiliated Faculty: Sultana Nahar, Anil Pradhan

Observing Facilities

MDM Observatory

Panoramic view of the MDM Observatory in winter

OSU is a 25% partner in the MDM Observatory at Kitt Peak, Arizona.  Along with partners Dartmouth College, Columbia University, Ohio University, and the University of Michigan, MDM operates a 2.4-meter and a 1.3-meter telescope equipped with modern optical and infrared imagers and spectrometers. The 2.4-meter Hiltner telescope is one of the best in its class anywhere, routinely delivering subarcsecond imaging, while the 1.3-meter McGraw Hill telescope can be flexibly scheduled to undertake long-term observational monitoring programs.  MDM is the primary small-project and student training telescope used by OSU astronomers.

In an age of giant 8- and 10-meter diameter telescopes, the smaller MDM telescopes are ideal for observations of the brighter nearby stars and galaxies, and for follow-up studies of X-ray sources discovered by space observatories like Chandra or XMM/Newton. They are also excellent for long-term studies of variable stars, active galaxies, and searches for extrasolar planetary systems. OSU is a leader in the development of new instrumentation and observing techniques designed to keep these smaller telescopes at the forefront of astronomical research.

The Large Binocular Telescope

Large Binocular Telescope on Mount Graham in southeastern arizona

Ohio State is a 16% partner in the Large Binocular Telescope (LBT), a twin 8.4-meter mirror telescope on Mt. Graham in Southern Arizona. OSU developed the large-mirror coating system for the twin 8.4-meter mirrors, built a fixed-secondary mirror system to help LBT begin operations before the arrival of the adaptive secondaries, and has commissioned two advanced Multi-Object Double Spectrographs (MODS), the facility optical spectrometers for the LBT.

The LBT, with its twin 8.4-meter diameter prime mirrors, is currently the world's largest optical/IR telescope on a single mount. With nearly 24 times the light gathering power of the Hubble Space Telescope, the LBT can obtain spectra of objects the Hubble can only image. Such spectra provide the essential information for determining distances, evolutionary state, and chemical composition of the most distant galaxies known in the universe. With the two MODS spectrographs built by OSU, LBT astronomers can study objects that were formed when the universe was less than 10% of its present age, and study how they have evolved into the galaxies and stars that we see around us today.

SMARTS

SMARTS observatory at Cerro Tololo Chile

OSU is a founding member of the SMARTS Consortium, which operates the small and medium aperture research telescopes at the Cerro Tololo Interamerican Observatory in Chile. Specifically, we have provided the ANDICAM dual optical/IR imager for the CTIO 1.3-meter telescope, and built the Y4KCam 4Kx4K CCD imager for the CTIO 1.0-meter telescope.

Sloan Digital Sky Survey

SDSS Sky Survey Redshift Slice

OSU is a long-standing partner in the Sloan Digital Sky Survey. Our involvement has included the Sloan Supernova Survey, the study of the content and structure of the Milky Way through the 250,000 stellar spectra from the SEGUE project, chemical abundances from the APOGEE project, planet detection from MARVELS, and the extraction of cosmological and galaxy formation parameters from SDSS databases, including most recently the SDSS-IV eBOSS project.

Dark Energy Survey

Simulated DECam Field of View

The OSU Astronomy Department and CCAPP are members of the Dark Energy Survey (DES) collaboration.  DES is designed to probe the origin of the accelerating universe and help uncover the nature of dark energy by measuring the 14-billion-year history of cosmic expansion with high precision.  The DECam survey camera was comissioned at the CTIO 4-meter Blanco Telescope in 2012 and the five-year survey began in 2013. 

Dark Energy Spectroscopic Instrument

Illustration of the Dark Energy Spectroscopic Instrument

The OSU Astronomy Department and CCAPP joined the Dark Energy Spectroscopic Instrument (DESI) collaboration in 2014.  DESI is a large new survey that aims to measure redshifts for over 35 million galaxies and quasars, and use the techniques of baryon acoustic oscilliations and redshift space distortions to investigate dark energy and modifications to general relativity. Astronomers and physicists at Ohio State are playing major roles in the construction of instrumentation for DESI, as well as planning for the survey. DESI is scheduled to begin in 2019 on the KPNO 4-m Mayall telescope and extend for five years. 

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