The DiskMass Survey. III. Stellar Kinematics Via Cross-Correlation

Type Journal Article
Names Kyle B. Westfall, Matthew A. Bershady, Marc A. W. Verheijen
Publication The Astrophysical Journal Supplement Series
Volume 193
Pages 21
Journal Abbreviation The Astrophysical Journal Supplement Series
Date March 1, 2011
DOI 10.1088/0067-0049/193/1/21
ISSN 0067-0049
URL http://adsabs.org/2011ApJS.193.21W
Library Catalog labs.adsabs.harvard.edu
Abstract We describe a new cross-correlation (CC) approach used by our survey to derive stellar kinematics from galaxy-continuum spectroscopy. This approach adopts the formal error analysis derived by Statler, but properly handles spectral masks. Thus, we address the primary concerns regarding application of the CC method to censored data, while maintaining its primary advantage by consolidating kinematic and template-mismatch information toward different regions of the CC function. We identify a systematic error in the nominal CC method of approximately 10% in velocity dispersion incurred by a mistreatment of detector-censored data, which is eliminated by our new method. We derive our approach from first principles, and we use Monte Carlo simulations to demonstrate its efficacy. An identical set of Monte Carlo simulations performed using the well-established penalized-pixel-fitting code of Cappellari & Emsellem compares favorably with the results from our newly implemented software. Finally, we provide a practical demonstration of this software by extracting stellar kinematics from SparsePak spectra of UGC 6918.
Tags Techniques: Spectroscopic, galaxies: kinematics and dynamics, galaxies: spiral, methods: data analysis
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