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Title: The Space Density of Intermediate-redshift, Extremely Compact, Massive Starburst Galaxies
Abstract

We present a measurement of the intrinsic space density of intermediate-redshift (z∼ 0.5), massive (M*∼ 1011M), compact (Re∼ 100 pc) starburst (ΣSFR∼ 1000Myr−1kpc−1) galaxies with tidal features indicative of them having undergone recent major mergers. A subset of them host kiloparsec-scale, > 1000 km s−1outflows and have little indication of AGN activity, suggesting that extreme star formation can be a primary driver of large-scale feedback. The aim for this paper is to calculate their space density so we can place them in a better cosmological context. We do this by empirically modeling the stellar populations of massive, compact starburst galaxies. We determine the average timescale on which galaxies that have recently undergone an extreme nuclear starburst would be targeted and included in our spectroscopically selected sample. We find that massive, compact starburst galaxies targeted by our criteria would be selectable for14824+27Myr and have an intrinsic space densitynCS(1.10.3+0.5)×106Mpc3. This space density is broadly consistent with ourz∼ 0.5 compact starbursts being the most extremely compact and star-forming low-redshift analogs of the compact star-forming galaxies in the early universe, as well as them being the progenitors to a fraction of intermediate-redshift, post-starburst, and compact quiescent galaxies.

 
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Award ID(s):
1813702 1813299
NSF-PAR ID:
10377481
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astronomical Journal
Volume:
164
Issue:
5
ISSN:
0004-6256
Format(s):
Medium: X Size: Article No. 222
Size(s):
["Article No. 222"]
Sponsoring Org:
National Science Foundation
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