Home > Research > Publications & Outputs > ALMA reveals metals yet no dust within multiple...

### Electronic data

• 1709.06569v1

Rights statement: This is an author-created, un-copyedited version of an article accepted for publication/published in The Astrophysical Journal. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The Version of Record is available online at doi: 10.3847/1538-4357/aa9931

Accepted author manuscript, 6.51 MB, PDF document

## ALMA reveals metals yet no dust within multiple components in CR7

Research output: Contribution to journalJournal article

Published
• J. Matthee
• D. Sobral
• F. Boone
• H. Röttgering
• D. Schaerer
• M. Girard
• A. Pallottini
• L. Vallini
• A. Ferrara
• B. Darvish
• B. Mobasher
Close
Article number 145 20/12/2017 The Astrophysical Journal 2 851 14 Published English

### Abstract

We present spectroscopic follow-up observations of CR7 with ALMA, targeted at constraining the infrared (IR) continuum and [CII]$_{158 \mu \rm m}$ line-emission at high spatial resolution matched to the HST/WFC3 imaging. CR7 is a luminous Ly$\alpha$ emitting galaxy at $z=6.6$ that consists of three separated UV-continuum components. Our observations reveal several well-separated components of [CII] emission. The two most luminous components in [CII] coincide with the brightest UV components (A and B), blue-shifted by $\approx 150$ km s$^{-1}$ with respect to the peak of Ly$\alpha$ emission. Other [CII] components are observed close to UV clumps B and C and are blue-shifted by $\approx300$ and $\approx80$ km s$^{-1}$ with respect to the systemic redshift. We do not detect FIR continuum emission due to dust with a 3$\sigma$ limiting luminosity L$_{\rm IR} (T_d = 35 \rm \, K) CR7s clumps have metallicities of$0.1\rm Z/Z_{\odot}0.2\$. The observed ISM structure of CR7 indicates that we are likely witnessing the build up of a central galaxy in the early Universe through complex accretion of satellites.

### Bibliographic note

This is an author-created, un-copyedited version of an article accepted for publication/published in The Astrophysical Journal. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The Version of Record is available online at doi: 10.3847/1538-4357/aa9931