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Title: Deep Ultraviolet, Emission-line Imaging of the Makani Galactic Wind
Abstract The Ovi1032, 1038 Å line is a key probe of cooling gas in the circumgalactic medium (CGM) of galaxies but has been observed to date primarily in absorption along single sight lines. We present deep Hubble Space Telescope (HST) Solar Blind Channel of the Advanced Camera for Surveys observations of the compact, massive starburst Makani. Makani hosts a 100 kpc, [Oii]-emitting galactic wind driven by two episodes of star formation over 400 Myr. We detect Oviand Lyαemission across the [Oii] nebula with similar morphology and extent, out tor≈ 50 kpc. Using differential narrowband imaging, we separate Lyαand Oviand show that the Oviemission is comparable in brightness to [Oii], withLO VI= 4 × 1042erg s−1. The similar hourglass morphology and size of [Oii] and Oviimplicate radiative cooling atT= 105.5K in a hot–cold interface. This may occur as theT> 107K CGM—or the hot fluid driving the wind—exchanges mass with theT≈ 104K clouds entrained in (or formed by) the wind. The optical/UV line ratios may be consistent with shock ionization, although uncertain attenuation and Lyαradiative transfer complicate the interpretation. The detection of Oviin Makani lies at the bleeding edge of the UV imaging capabilities of HST and provides a benchmark for future emission-line imaging of the CGM with a wide-area UV telescope.  more » « less
Award ID(s):
2206473
PAR ID:
10638720
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
The Astrophysical Journal
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
986
Issue:
1
ISSN:
0004-637X
Page Range / eLocation ID:
87
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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