_version_ 1866914795303731200
author Loiacono, Federica
Decarli, Roberto
Mignoli, Marco
Farina, Emanuele Paolo
Bañados, Eduardo
Bosman, Sarah
Eilers, Anna-Christina
Schindler, Jan-Torge
Strauss, Michael A.
Vestergaard, Marianne
Wang, Feige
Blecha, Laura
Carilli, Chris L.
Comastri, Andrea
Connor, Thomas
Costa, Tiago
Dotti, Massimo
Fan, Xiaohui
Gilli, Roberto
Jun, Hyunsung D.
Liu, Weizhe
Lupi, Alessandro
Marshall, Madeline A.
Mazzucchelli, Chiara
Meyer, Romain A.
Neeleman, Marcel
Overzier, Roderik
Pensabene, Antonio
Riechers, Dominik A.
Trakhtenbrot, Benny
Trebitsch, Maxime
Venemans, Bram
Walter, Fabian
Yang, Jinyi
author_facet Loiacono, Federica
Decarli, Roberto
Mignoli, Marco
Farina, Emanuele Paolo
Bañados, Eduardo
Bosman, Sarah
Eilers, Anna-Christina
Schindler, Jan-Torge
Strauss, Michael A.
Vestergaard, Marianne
Wang, Feige
Blecha, Laura
Carilli, Chris L.
Comastri, Andrea
Connor, Thomas
Costa, Tiago
Dotti, Massimo
Fan, Xiaohui
Gilli, Roberto
Jun, Hyunsung D.
Liu, Weizhe
Lupi, Alessandro
Marshall, Madeline A.
Mazzucchelli, Chiara
Meyer, Romain A.
Neeleman, Marcel
Overzier, Roderik
Pensabene, Antonio
Riechers, Dominik A.
Trakhtenbrot, Benny
Trebitsch, Maxime
Venemans, Bram
Walter, Fabian
Yang, Jinyi
contents We present JWST/NIRSpec integral field data of the quasar PJ308-21 at $z=6.2342$. As shown by previous ALMA and HST imaging, the quasar has two companion sources, interacting with the quasar host galaxy. The high-resolution G395H/290LP NIRSpec spectrum covers the $2.87-5.27\ \rm μm$ wavelength range and shows the rest-frame optical emission of the quasar with exquisite quality ($S/N\sim 100-400$ per spectral element). Based on the H$β$ line from the broad line region, we obtain an estimate of the black hole mass $M_{\rm BH,Hβ}\sim 2.7\times 10^{9}\ \rm M_{\odot}$. This value is within a factor $\lesssim 1.5$ of the H$α$-based black hole mass from the same spectrum ($M_{\rm BH, Hα}\sim 1.93\times 10^{9}\ \rm M_{\odot}$) and is consistent with a previous estimate relying on the MgII $λ2799$ ($M_{\rm BH, MgII}\sim 2.65\times 10^{9}\ \rm M_{\odot}$). All these $M_{\rm BH}$ are within the $\sim 0.5$ dex intrinsic scatter of the adopted mass calibrations. The high Eddington ratio of PJ308-21 $λ_{\rm Edd,Hβ}\sim 0.67$ ($λ_{\rm Edd,Hα}\sim 0.96$) is in line with the overall quasar population at $z \gtrsim 6$. The relative strengths of the [OIII], FeII and H$β$ lines are consistent with the empirical "Eigenvector 1" correlations as observed for low redshift quasars. We find evidence for blueshifted [OIII] $λ5007$ emission with a velocity offset $Δv_{\rm [OIII]}=-1922\pm 39$ km s$^{-1}$ from the systemic velocity and a $\rm FWHM([OIII])=2776^{+75}_{-74}$ km s$^{-1}$. This may be the signature of an outflow from the nuclear region, despite the true values of $Δv_{\rm [OIII]}$ and $\rm FWHM([OIII])$ are likely more uncertain due to the blending with H$β$ and FeII lines. Our study demonstrates the unique capabilities of NIRSpec in capturing quasar spectra at cosmic dawn and studying their properties in unprecedented detail.
format Preprint
id arxiv_https___arxiv_org_abs_2402_13319
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle A quasar-galaxy merger at $z\sim6.2$: black hole mass and quasar properties from the NIRSpec spectrum
Loiacono, Federica
Decarli, Roberto
Mignoli, Marco
Farina, Emanuele Paolo
Bañados, Eduardo
Bosman, Sarah
Eilers, Anna-Christina
Schindler, Jan-Torge
Strauss, Michael A.
Vestergaard, Marianne
Wang, Feige
Blecha, Laura
Carilli, Chris L.
Comastri, Andrea
Connor, Thomas
Costa, Tiago
Dotti, Massimo
Fan, Xiaohui
Gilli, Roberto
Jun, Hyunsung D.
Liu, Weizhe
Lupi, Alessandro
Marshall, Madeline A.
Mazzucchelli, Chiara
Meyer, Romain A.
Neeleman, Marcel
Overzier, Roderik
Pensabene, Antonio
Riechers, Dominik A.
Trakhtenbrot, Benny
Trebitsch, Maxime
Venemans, Bram
Walter, Fabian
Yang, Jinyi
Astrophysics of Galaxies
Cosmology and Nongalactic Astrophysics
We present JWST/NIRSpec integral field data of the quasar PJ308-21 at $z=6.2342$. As shown by previous ALMA and HST imaging, the quasar has two companion sources, interacting with the quasar host galaxy. The high-resolution G395H/290LP NIRSpec spectrum covers the $2.87-5.27\ \rm μm$ wavelength range and shows the rest-frame optical emission of the quasar with exquisite quality ($S/N\sim 100-400$ per spectral element). Based on the H$β$ line from the broad line region, we obtain an estimate of the black hole mass $M_{\rm BH,Hβ}\sim 2.7\times 10^{9}\ \rm M_{\odot}$. This value is within a factor $\lesssim 1.5$ of the H$α$-based black hole mass from the same spectrum ($M_{\rm BH, Hα}\sim 1.93\times 10^{9}\ \rm M_{\odot}$) and is consistent with a previous estimate relying on the MgII $λ2799$ ($M_{\rm BH, MgII}\sim 2.65\times 10^{9}\ \rm M_{\odot}$). All these $M_{\rm BH}$ are within the $\sim 0.5$ dex intrinsic scatter of the adopted mass calibrations. The high Eddington ratio of PJ308-21 $λ_{\rm Edd,Hβ}\sim 0.67$ ($λ_{\rm Edd,Hα}\sim 0.96$) is in line with the overall quasar population at $z \gtrsim 6$. The relative strengths of the [OIII], FeII and H$β$ lines are consistent with the empirical "Eigenvector 1" correlations as observed for low redshift quasars. We find evidence for blueshifted [OIII] $λ5007$ emission with a velocity offset $Δv_{\rm [OIII]}=-1922\pm 39$ km s$^{-1}$ from the systemic velocity and a $\rm FWHM([OIII])=2776^{+75}_{-74}$ km s$^{-1}$. This may be the signature of an outflow from the nuclear region, despite the true values of $Δv_{\rm [OIII]}$ and $\rm FWHM([OIII])$ are likely more uncertain due to the blending with H$β$ and FeII lines. Our study demonstrates the unique capabilities of NIRSpec in capturing quasar spectra at cosmic dawn and studying their properties in unprecedented detail.
title A quasar-galaxy merger at $z\sim6.2$: black hole mass and quasar properties from the NIRSpec spectrum
topic Astrophysics of Galaxies
Cosmology and Nongalactic Astrophysics
url https://arxiv.org/abs/2402.13319