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arXiv · 2109.00576

Spatially resolved Lyman-$α$ emission around radio bright quasars

Gitika Shukla·Raghunathan Srianand·Neeraj Gupta·Patrick Petitjean·Andrew J. Baker·Jens-Kristian Krogager·Pasquier Noterdaeme
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Abstract

We use Southern African Large Telescope (SALT) to perform long-slit spectroscopic observations of 23 newly discovered radio-loud quasars (RLQs) at $2.7 $1000 km/s in all, except one). Using the samples of high-$z$ radio-loud quasars and galaxies from literature, we confirm the correlation between the Ly$α$ halo luminosity and its size with radio power ($L_{\rm 420MHz}$). The same quantities are found to be correlating weakly with the projected linear size of the radio emission. Our sample is the second largest sample of RLQs being studied for the presence of diffuse Ly$α$ emission and fills in a redshift gap between previous such studies. Integral Field Spectroscopy is required to fully understand the relationship between the large scale radio emission and the overall distribution, kinematics and over density of Ly$α$ emission in the field of these RLQs.

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Gitika Shukla, Raghunathan Srianand, Neeraj Gupta, Patrick Petitjean, Andrew J. Baker, Jens-Kristian Krogager, Pasquier Noterdaeme. 2021-11-29. Spatially resolved Lyman-$α$ emission around radio bright quasars. https://doi.org/10.1093/mnras%2Fstab3467

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