NOAO > Observing Info > Approved Programs > 2012A-0391
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NOAO > Observing Info > Approved Programs > 2012A-0391 |
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PI: Paco Najarro, Center of Astrobiology, CAB, CSIC-INTA, Spain, najarro@cab.inta-csic.es
Address: Spain
CoI: Donald Figer, Rochester Institute of Technology (CIS)
CoI: Tom Geballe, Gemini Observatory - North
CoI: Diego de la Fuente, Center of Astrobiology, CAB, CSIC, Spain
Title: Metallicity in the Quintuplet Cluster and the Galactic Center: Evidence for a top-heavy star formation history?
Abstract:
The Quintuplet Cluster, in our Galaxy, is one of the most massive resolved
young clusters in the Local Group and is a test bed for understanding the
star formation history of the region and for the top-heavy star formation
scenario, via its alpha-elements and iron absolute abundances and their
corresponding ratios. We have developed two different techniques to derive
metallicity from infrared observations of LBVs and WR stars. For LBVs,
absolute alpha-element (Si, Mg) and iron abundances may be obtained, while
for WRs it is possible to derive the alpha-element (oxygen) abundance of the
natal cloud. We propose to finish our partially completed 2011A Gemini
program to obtain near-infrared spectra of the high-mass stars in the
Quintuplet cluster and isolated massive stars in the inner Galactic Center
region in order to extract stellar properties, ages, and abundances and hence
address the top-heavy question. The excellent performance of GNIRS,
especially at the shorter NIR wavelengths where extinction to the Galactic
center is high allows us to extend spectral coverage of the Quintuplet
Cluster stars to shorter wavelengths than previously and obtain for some
stars new and crucial information on the Nitrogen abundance (metallicity) and
temperature (stellar luminosity).
National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360
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NOAO > Observing Info > Approved Programs > 2012A-0391 |
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