Bahram Mobasher

Research Interests:

• Observational Astronomy

Education:

Ph.D. 1988, University of Durham, Durham, U.K.

Current Research:

My main research interest is focused on the study of formation and evolution of galaxies using multi-waveband galaxy surveys obtained with 8-10 meter ground-based telescopes (Gemini, VLT, Subaru, Keck) and space facilities (HST, Spitzer, GALEX, Chandra). Using the observational data and stellar synthesis models, I study properties of galaxies as a function of star formation rate, morphology, environment, color, luminosity and redshift. Over the past two years I have been involved in the following studies: developing the Balmer Break technique for identifying very high redshift massive galaxies, using the combined HST and Spitzer data; discovery of an extremely massive and evolved galaxy at z ~ 7 (this has been the subject of extensive press release); study of the density-morphology relation over the largest dynamic range in density, and its evolution with redshift; planning and execution of the new Hubble Ultra Deep Field (HUDF), doubling the area and increasing the depth of the original HUDF; finding candidates for galaxies at z ~ 8 through searches for J-band dropouts in the new HUDF; study of the properties (SFR, mass, extinction) of high redshift galaxies selected through narrow-band Lyman emission (LAE) at z = 5.7 and comparison with Lyman Break Galaxies at the same redshift; developing a photometric redshift code to calculate redshift, spectral types and stellar masses of galaxies. I have been seriously involved in the Great Observatories Origins Deep Survey (GOODS) and The Cosmic Evolution Survey (COSMOS) projects. I have also been leading parts of the new HST treasury project to survey the core and outskirt of the Coma cluster.

Selected Publications:

1. Mobasher, B.; Jogee, S.; Dahlen, T.; De Mallo, D.; Lucas, R.A.; Conselice, C.; Grogin, N.; Livio, M., Structure and Evolution of Starburst and Normal Galaxies, Ap. J. 2004, 600, 143.
2. Mobasher, B., et al., Photometric Redshifts to Galaxies in the Southern GOODS Field, Ap. J. 2004, 600, 167.
3. Riess, A.G., Strolger, L., Tonry, J., Casertano, S., Ferguson, H.C., Mobasher, B., Challis, P., Fillipenko, A.V., Saurabh, J., et al., Type Ia Supernovae Discoveries at z > 1 from the Hubble Space Telescope: Evidence for Past Deceleration and Constraints on Dark-Energy Evolution, Ap. J. 2004, 607, 665. (Ranked as the second most cited paper in astrophysics in 2005).
4. Dahlen, T., Strolger, L., Riess, A.G., Mobasher, R, Chary, R., et al., High Redshift Supernovae Rates, Ap. J. 2004, 613, 189.
5. Dahlen, T., Mobasher, B., Dickinson, M., Ferguson, H., and Giavalisco, M., Evolution of Rest-Frame Optical and Near-Infrared Galaxy Luminosity Functions and Their Type-Dependence, Ap. J. 2005, 631, 126.
6. Mobasher, B., et al., Evidence for a Massive Post-Starburst Galaxy at z ~ 6.5, Ap. J 2005, 635, 832. (This was ranked among the top 100 most outstanding science results in 2005, selected by the Science News and Discover magazines).
7. Panagia, N., Fall, M., Mobasher, B., Dickinson, M., Ferguson, R., Giavalisco, M., and Wiklind, T., Direct Evidence for an Early Reionization of the Universe?, Ap. J. Lett., 2005, 633, 1.
8. Ajiki, M., Mobasher, B., Taniguchi, Y., Shioya, Y. et al., Narrow-band Survey of the GOODS Fields: Search for Lyman α Emitters at z = 5.7, Ap.J. 2006, 638, 596.
9. Capak, P., Abraham, R., Ellis, R.S., Mobasher, B., Scoville, N.Z., Sheth, K., The Effects of Environment on Morphological Evolution at 0 < z < 1.2 in the COSMOS Survey, Ap. J. Suppl. 2007, 172, 284.