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Title: The HI Content of Galaxies as a Function of Local Density and Large-Scale Environment
We examine the HI content of galaxies as a function of environment, based on a catalogue of 41527 galaxies that are part of the 70% complete Arecibo Legacy Fast-ALFA (ALFALFA) survey. We use nearest-neighbor methods to characterize local environment, and a modified version of the algorithm developed for the Galaxy and Mass Assembly (GAMA) survey to classify large-scale environment as group, filament, tendril, or void. We compare the HI content in these environments using statistics that include both HI detections and the upper limits on detections from ALFALFA. The large size of the sample allows to statistically compare the HI content in different environments for early-type galaxies as well as late-type galaxies. This work is supported by NSF grants AST-1211005 and AST-1637339, the Skidmore Faculty-Student Summer Research program, and the Schupf Scholars program.  more » « less
Award ID(s):
1637339
NSF-PAR ID:
10030119
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Date Published:
Journal Name:
American Astronomical Society ... meeting
Volume:
229
ISSN:
2152-887X
Page Range / eLocation ID:
347.39
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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