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arXiv · 1909.00027

The z=7.54 Quasar ULAS J1342+0928 Is Hosted by a Galaxy Merger

Eduardo Banados·Mladen Novak·Marcel Neeleman·Fabian Walter·Roberto Decarli·Bram P. Venemans·Chiara Mazzucchelli·Chris Carilli·Feige Wang·Xiaohui Fan·Emanuele P. Farina·Hans-Walter Rix
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Abstract

We present ALMA 0.28"x0.20" (1.4kpc x 1.0kpc) resolution observations of the [CII] 158um line and underlying dust continuum in the host galaxy of the most distant quasar currently known, ULAS J1342+0928 at z=7.5413. Both the [CII] and continuum are detected and spatially resolved. The [CII] line is ~1.5 times more extended than the continuum emission, showing an elongated and complex structure of approximately 3.2kpc x 6.4kpc. Two separate peaks are clearly seen (>6sigma each) in three 100 km/s width [CII] channel maps. The velocity field of the [CII] gas does not show evidence of a coherent rotation field but rather chaotic motion, reminiscent of an on-going merger.

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Eduardo Banados, Mladen Novak, Marcel Neeleman, Fabian Walter, Roberto Decarli, Bram P. Venemans, Chiara Mazzucchelli, Chris Carilli, Feige Wang, Xiaohui Fan, Emanuele P. Farina, Hans-Walter Rix. 2019-08-30. The z=7.54 Quasar ULAS J1342+0928 Is Hosted by a Galaxy Merger. https://doi.org/10.3847/2041-8213%2Fab3659

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