NOAO >   Observing Info >   Approved Programs >   2012A-0451

Small NOAO Logo

Proposal Information for 2012A-0451


PI: Richard McDermid, Gemini Observatory - North, rmcdermid@gemini.edu
Address: Gemini Observatory, 670 N. Aohoku Place, Hilo, HI 96720, USA

CoI: Claudia Maraston, University of Portsmouth
CoI: Lisa Young, New Mexico Institute of Mining and Technology
CoI: Harald Kuntschner, ESO, Germany
CoI: Tom Geballe, Gemini Observatory - North
CoI: Michele Cappellari, University of Oxford
CoI: Eric Emsellem, ESO, Germany
CoI: Davor Krajnovic, ESO, Germany
CoI: Roger Davies, University of Oxford
CoI: Martin Bureau, University of Oxford
CoI: Leo Blitz, UC Berkeley (Astronomy)
CoI: Alison Crocker, University of Massachusetts
CoI: Katherine Alatalo, UC Berkeley (Astronomy)

Title: Characterizing the Near-Infrared SEDs of Early-Type Galaxies with Atlas3D: Answering the TP-AGB Question

Abstract: The near-infrared (NIR) region (1-2.4 micron) contains signatures of AGN, molecular gas, ionization mechanisms, stellar evolution phases and dust. Moreover, the NIR range offers significantly lower dust obscuration, high spatial resolution with adaptive optics, and will be the standard spectral regime for future studies using JWST. Despite its enormous information content and importance, the NIR is largely unexplored in galaxies, and remarkably little is known about how NIR diagnostics contrast with optical tracers. We propose to undertake crucial groundwork in characterizing the NIR spectral energy distribution of nearby galaxies, drawing from the Atlas3D sample of early-type galaxies (ETGs). The sample has excellent supporting data, including optical integral-field spectroscopy, interferometric CO maps, UV to mid-IR photometry, making these the best understood ETGs available. In this pilot program, we focus on stellar populations, and propose a GNIRS cross-dispersed 'snapshot' survey of 26 galaxies from Atlas3D spanning mean ages of 1-14 Gyr, at similar velocity dispersion and metallicity. This will provide a conclusive view on the debated importance of TP-AGB stars in the young stellar populations of galaxies. We will simultaneously investigate the interactions of putative AGN and molecular gas - a mechanism for 'feedback' quenching star formation, often quoted but little understood.


National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360



NOAO >   Observing Info >   Approved Programs >   2012A-0451

noaoprop-help@noao.edu

Small NOAO Logo