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Title: Rotation Curve Measurement of Dark Matter Content of a z ∼ 0.5 Galaxy
Abstract Measurements of galaxy rotation curves provide direct measurements of the distribution of baryonic and dark matter in galaxies. Here, we present spectroscopic confirmation and one such rotation curve for az = 0.5325 galaxy observed with Keck I/MOSFIRE as a filler target for the Web Epoch of Reionization Survey. The rotation curve was derived from Hα6563 Å emission out to a galactocentric radius of approximately 24 kpc. The target's rotation curve is well fit by an arctangent curve, that when combined with broadbanned photometric constraints on the galaxy’s stellar mass, predicts a dark matter fraction consistent with results from the literature forz ∼ 0.5. We constrain the estimate for this galaxy's dark matter fraction to be 93%, out to a galactocentric radius of 30 kpc.  more » « less
Award ID(s):
2009577
PAR ID:
10559977
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Research Notes of the American Astronomical Society
Date Published:
Journal Name:
Research Notes of the AAS
Volume:
7
Issue:
5
ISSN:
2515-5172
Page Range / eLocation ID:
110
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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