We present deep (265 ks) Chandra X-ray observations of PSO
J352.4034$-$15.3373, a quasar at z=5.831 that, with a radio-to-optical flux
ratio of R>1000, is one of the radio-loudest quasars in the early universe and
is the only quasar with observed extended radio jets of kpc-scale at $z \gtrsim
6$. Modeling the X-ray spectrum of the quasar with a power law, we find a best
fit of $\Gamma = 1.99^+0.29_-0.28$, leading to an X-ray luminosity of
$L_2-10 = 1.26^+0.45_-0.33 10^45\ erg\ s^-1$ and
an X-ray to UV brightness ratio of $\alpha_OX = -1.36 0.11$. We
identify a diffuse structure 50 kpc ($\sim8^\prime\prime$) to the NW of the
quasar along the jet axis that corresponds to a $3\sigma$ enhancement in the
angular density of emission and can be ruled out as a background fluctuation
with a probability of P=0.9985. While with few detected photons the spectral
fit of the structure is uncertain, we find that it has a luminosity of
$L_2-10\sim10^44\ erg\ s^-1$. These observations therefore
potentially represent the most distant quasar jet yet seen in X-rays. We find
no evidence for excess X-ray emission where the previously-reported radio jets
are seen (which have an overall linear extent of $0.^\prime\prime28$), and a
bright X-ray point source located along the jet axis to the SE is revealed by
optical and NIR imaging to not be associated with the quasar.
Description
Enhanced X-ray Emission from the Most Radio-Powerful Quasar in the Universe's First Billion Years
%0 Generic
%1 connor2021enhanced
%A Connor, Thomas
%A Bañados, Eduardo
%A Stern, Daniel
%A Carilli, Chris
%A Fabian, Andrew
%A Momjian, Emmanuel
%A Rojas-Ruiz, Sofía
%A Decarli, Roberto
%A Farina, Emanuele Paolo
%A Mazzucchelli, Chiara
%A Earnshaw, Hannah P.
%D 2021
%K library
%T Enhanced X-ray Emission from the Most Radio-Powerful Quasar in the
Universe's First Billion Years
%U http://arxiv.org/abs/2103.03879
%X We present deep (265 ks) Chandra X-ray observations of PSO
J352.4034$-$15.3373, a quasar at z=5.831 that, with a radio-to-optical flux
ratio of R>1000, is one of the radio-loudest quasars in the early universe and
is the only quasar with observed extended radio jets of kpc-scale at $z \gtrsim
6$. Modeling the X-ray spectrum of the quasar with a power law, we find a best
fit of $\Gamma = 1.99^+0.29_-0.28$, leading to an X-ray luminosity of
$L_2-10 = 1.26^+0.45_-0.33 10^45\ erg\ s^-1$ and
an X-ray to UV brightness ratio of $\alpha_OX = -1.36 0.11$. We
identify a diffuse structure 50 kpc ($\sim8^\prime\prime$) to the NW of the
quasar along the jet axis that corresponds to a $3\sigma$ enhancement in the
angular density of emission and can be ruled out as a background fluctuation
with a probability of P=0.9985. While with few detected photons the spectral
fit of the structure is uncertain, we find that it has a luminosity of
$L_2-10\sim10^44\ erg\ s^-1$. These observations therefore
potentially represent the most distant quasar jet yet seen in X-rays. We find
no evidence for excess X-ray emission where the previously-reported radio jets
are seen (which have an overall linear extent of $0.^\prime\prime28$), and a
bright X-ray point source located along the jet axis to the SE is revealed by
optical and NIR imaging to not be associated with the quasar.
@misc{connor2021enhanced,
abstract = {We present deep (265 ks) Chandra X-ray observations of PSO
J352.4034$-$15.3373, a quasar at z=5.831 that, with a radio-to-optical flux
ratio of R>1000, is one of the radio-loudest quasars in the early universe and
is the only quasar with observed extended radio jets of kpc-scale at $z \gtrsim
6$. Modeling the X-ray spectrum of the quasar with a power law, we find a best
fit of $\Gamma = 1.99^{+0.29}_{-0.28}$, leading to an X-ray luminosity of
$L_{2-10} = 1.26^{+0.45}_{-0.33} \times 10^{45}\ {\rm erg}\ {\rm s}^{-1}$ and
an X-ray to UV brightness ratio of $\alpha_{\rm OX} = -1.36 \pm 0.11$. We
identify a diffuse structure 50 kpc (${\sim}8^{\prime\prime}$) to the NW of the
quasar along the jet axis that corresponds to a $3\sigma$ enhancement in the
angular density of emission and can be ruled out as a background fluctuation
with a probability of P=0.9985. While with few detected photons the spectral
fit of the structure is uncertain, we find that it has a luminosity of
$L_{2-10}\sim10^{44}\ {\rm erg}\ {\rm s}^{-1}$. These observations therefore
potentially represent the most distant quasar jet yet seen in X-rays. We find
no evidence for excess X-ray emission where the previously-reported radio jets
are seen (which have an overall linear extent of $0.^{\prime\prime}28$), and a
bright X-ray point source located along the jet axis to the SE is revealed by
optical and NIR imaging to not be associated with the quasar.},
added-at = {2021-03-09T06:35:34.000+0100},
author = {Connor, Thomas and Bañados, Eduardo and Stern, Daniel and Carilli, Chris and Fabian, Andrew and Momjian, Emmanuel and Rojas-Ruiz, Sofía and Decarli, Roberto and Farina, Emanuele Paolo and Mazzucchelli, Chiara and Earnshaw, Hannah P.},
biburl = {https://www.bibsonomy.org/bibtex/27fb8ea90d6b24784c141a8c5b6ff1a96/gpkulkarni},
description = {Enhanced X-ray Emission from the Most Radio-Powerful Quasar in the Universe's First Billion Years},
interhash = {899fb1bb0588db4135c5e91498ae7a62},
intrahash = {7fb8ea90d6b24784c141a8c5b6ff1a96},
keywords = {library},
note = {cite arxiv:2103.03879Comment: 16 pages, 7 Figures. Accepted for publication the Astrophysical Journal},
timestamp = {2021-03-09T06:35:34.000+0100},
title = {Enhanced X-ray Emission from the Most Radio-Powerful Quasar in the
Universe's First Billion Years},
url = {http://arxiv.org/abs/2103.03879},
year = 2021
}