Department of Astronomy Center for Radiophysics & Space Research

Dominik Riechers

Assistant Professor of Astronomy
Dominik Riechers
Specialty areas

Observational astronomy; physical properties of distant galaxies; galaxy formation and evolution through cosmic times.

Research Projects

Molecular gas and dust as drivers for star formation and black hole growth in the early universe; total molecular gas masses and gas composition of high-redshift galaxies; searches for H2O in the first generation of starbursts in the universe; high-resolution molecular line imaging of distant galaxies (EVLA/ALMA); "blind" CO redshift searches; molecular "deep fields"/measuring the CO luminosity function; the "star formation law" for distant galaxies; active galactic nucleus-starburst connection in high redshift galaxies.


Dominik A. Riechers' research combines astronomical data sets from many observatories on Earth and in space with physical modeling to better understand the initial conditions for star formation in galaxies in the early universe, and their evolution with cosmic time. These studies place particular emphasis on the physical and chemical properties of the (molecular) gas out of which stars and circumstellar environments (the birth sites of planets) form. Studies of the molecular gas content of galaxies throughout cosmic times offer crucial insight into the initial conditions for active star formation and the buildup of stellar mass (the result of star formation) at different cosmic epochs, providing a means to understand the origins of the universe as we see it at present day. It thus is of the utmost importance to develop a detailed understanding of the gas properties of galaxies back to the earliest cosmic epochs (lookback times of almost 13 billion years, when the infant universe had only 5% of its current age), and to trace their general evolution as a function of age of the universe.

Such investigations require observations of the cold and distant universe, when most of the baryons in and around galaxies were still in the form of gas and dust, rather than stars. Due to the low energy of the radiation emitted by cold molecular gas and technical limitations, such studies were extremely challenging in the past, and have left even some of the basic questions in this field largely unanswered. Thus, this exciting field strives with enormous discovery potential, and new and upcoming facilities such as the Atacama Large Millimeter/submillimeter Array (ALMA), the Expanded Very Large Array (EVLA) and the Cerro Chajnantor Atacama Telescope (CCAT) render the current decade the one where most of the mysteries in this exciting field will ultimately be solved. The search for our cosmic origins and the physical properties of the universe as traced by the dynamical properties of galaxies and the stars that from out of the gas reservoirs in them are what drive Dominik A. Riechers' primal research interest in this enigmatic area of science.

Selected Publications
 (Full Publication List on ADS:

- Riechers, D. A., Carilli, C. L., Maddalena, R. J., Hodge, J., Harris, 
A. I., Baker, A. J., Walter, F., Wagg, J., Vanden Bout, P. A., Weiss, A., & Sharon, C. E., "CO(1-0) in z>2 Quasar Host Galaxies: No Evidence for Extended Molecular Gas Reservoirs", 2011, ApJ, 739, L32
- Riechers, D. A., Hodge, J., Walter, F., Carilli, C. L., & Bertoldi, 
F., "Extended Cold Molecular Gas Reservoirs in z~3.4 Submillimeter Galaxies", 2011, ApJ, 739, L31
- Riechers, D. A., "Molecular Gas in Lensed z>2 Quasar Host Galaxies 
and the Star Formation Law for Galaxies with Active Galactic Nuclei", 2011, ApJ, 730, 108
- Smolcic, V., & Riechers, D. A., "The Molecular Gas Content of z~4 
Quasar Host Galaxies: No Evidence for Extended Molecular Gas
Reservoirs", 2006, ApJ, 650, 604