PI: Eiichi Egami, University of Arizona, email@example.com
Address: Steward observatory, 933 N. Cherry Ave., Tucson, AZ 85750, USA
CoI: Alexander Lisetsky, University of Arizona
CoI: Jeff Portouw, University of Arizona
Title: Gemini/Palomar Near-IR Spectroscopy of Powerful H_2 Emission from Brightest Cluster Galaxies
Abstract: One big surprise with recent Spitzer/IRS observations is the discovery of extragalactic sources showing extremely powerful mid-IR molecular hydrogen (\molh) emission. The most spectacular is the brightest cluster galaxy (BCG) in the cluster Zwicky 3146 with a corresponding warm \molh gass mass of ~10^10M_\odot. Its brightest mid-IR \molh lines are so luminous (~ 10^9 L_\odot) that they would be detectable up to z~ 10 with the next generation of space infrared observatories (e.g., with BLISS on SPICA). Considering that \molh molecules were the main coolant in the metal-free evironment that might have existed in the first generation of galaxies, these \molh-luminous BCGs might hold a key to understanding forming galaxies at high redshift. Here, we propose to conduct near-IR sepctroscopy of 10 \molh-luminous BCGs, newly found in our Spitzer/IRS survey, using (1) Gemini-N/NIFS in the Altair+LGS AO mode (3 BCGs) and seeing-limited mode (7 BCGs), and (2) Hale/TripleSpec (9 BCGs). We will examine the spatial distribution and kinematics of \molh-emitting gas, and will investigate the excitation mechanism by constructing accurate \molh level population diagrams.
National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360