Infrared Galaxies in the Field of the Massive Cluster Abell S1063: Discovery of a Luminous Kiloparsec-Sized HII Region in a Gravitationally Lensed IR-Luminous Galaxy at $z=0.6$. (arXiv:1904.07256v1 [astro-ph.GA])
<a href="http://arxiv.org/find/astro-ph/1/au:+Walth_G/0/1/0/all/0/1">Gregory L. Walth</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Egami_E/0/1/0/all/0/1">Eiichi Egami</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Clement_B/0/1/0/all/0/1">Benjamin Clément</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Rawle_T/0/1/0/all/0/1">Timothy D. Rawle</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Rex_M/0/1/0/all/0/1">Marie Rex</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Richard_J/0/1/0/all/0/1">Johan Richard</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Perez_Gonzalez_P/0/1/0/all/0/1">Pablo Pérez-González</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Boone_F/0/1/0/all/0/1">Frédéric Boone</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Dessauges_Zavadsky_M/0/1/0/all/0/1">Miroslava Dessauges-Zavadsky</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Portouw_J/0/1/0/all/0/1">Jeff Portouw</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Weiner_B/0/1/0/all/0/1">Benjamin Weiner</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+McGreer_I/0/1/0/all/0/1">Ian McGreer</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Schneider_E/0/1/0/all/0/1">Evan Schneider</a>
Using the Spitzer Space Telescope and Herschel Space Observatory, we have
conducted a survey of infrared galaxies in the field of the galaxy cluster
Abell S1063 (AS1063) at $z=0.347$, which is one of the most massive clusters
known and a target of the HST CLASH and Frontier-Field surveys. The
Spitzer/MIPS 24 $mu$m and Herschel/PACS & SPIRE images revealed that the core
of AS1063 is surprisingly devoid of infrared sources, showing only a few
detectable sources within the central r$sim1^{prime}$. There is, however, one
particularly bright source (2.3 mJy at 24 $mu$m; 106 mJy at 160 $mu$m), which
corresponds to a background galaxy at $z=0.61$. The modest magnification factor
(4.0$times$) implies that this galaxy is intrinsically IR-luminous (L$_{rm
IR}=3.1times10^{11} rm L_{odot}$). What is particularly interesting about
this galaxy is that HST optical/near-infrared images show a remarkably bright
and large (1 kpc) clump at one edge of the disk. Our follow-up
optical/near-infrared spectroscopy shows Balmer (H$alpha$-H8) and forbidden
emission from this clump ([OII] $lambda$3727, [OIII]
$lambdalambda$4959,5007, [NII] $lambdalambda$6548,6583), indicating that it
is a HII region. The HII region appears to have formed in-situ, as
kinematically it is part of a rotating disk, and there is no evidence of nearby
interacting galaxies. With an extinction correction of A$_{rm V}=1.5$ mag, the
star formation rate of this giant HII region is $sim$10 M$_{odot}$ yr$^{-1}$,
which is exceptionally large, even for high redshift HII regions. Such a large
and luminous HII region is often seen at $zsim2$ but quite rare in the nearby
Universe.
Using the Spitzer Space Telescope and Herschel Space Observatory, we have
conducted a survey of infrared galaxies in the field of the galaxy cluster
Abell S1063 (AS1063) at $z=0.347$, which is one of the most massive clusters
known and a target of the HST CLASH and Frontier-Field surveys. The
Spitzer/MIPS 24 $mu$m and Herschel/PACS & SPIRE images revealed that the core
of AS1063 is surprisingly devoid of infrared sources, showing only a few
detectable sources within the central r$sim1^{prime}$. There is, however, one
particularly bright source (2.3 mJy at 24 $mu$m; 106 mJy at 160 $mu$m), which
corresponds to a background galaxy at $z=0.61$. The modest magnification factor
(4.0$times$) implies that this galaxy is intrinsically IR-luminous (L$_{rm
IR}=3.1times10^{11} rm L_{odot}$). What is particularly interesting about
this galaxy is that HST optical/near-infrared images show a remarkably bright
and large (1 kpc) clump at one edge of the disk. Our follow-up
optical/near-infrared spectroscopy shows Balmer (H$alpha$-H8) and forbidden
emission from this clump ([OII] $lambda$3727, [OIII]
$lambdalambda$4959,5007, [NII] $lambdalambda$6548,6583), indicating that it
is a HII region. The HII region appears to have formed in-situ, as
kinematically it is part of a rotating disk, and there is no evidence of nearby
interacting galaxies. With an extinction correction of A$_{rm V}=1.5$ mag, the
star formation rate of this giant HII region is $sim$10 M$_{odot}$ yr$^{-1}$,
which is exceptionally large, even for high redshift HII regions. Such a large
and luminous HII region is often seen at $zsim2$ but quite rare in the nearby
Universe.
http://arxiv.org/icons/sfx.gif
