J/A+A/698/A145 Luminous quasars at z∼5 absorbers (Brazzini+, 2025)
Multi-phase investigation of outflows in the circumgalactic and interstellar
media of luminous quasars at z∼5.
Brazzini M., D'Odorico V., Bischetti M., Feruglio C., Cupani G., Becker G.,
Tripodi R.
<Astron. Astrophys. 698, A145 (2025)>
=2025A&A...698A.145B 2025A&A...698A.145B (SIMBAD/NED BibCode)
ADC_Keywords: QSOs ; Redshifts ; Spectroscopy ; Equivalent widths
Keywords: galaxies: active - galaxies: evolution - galaxies: high-redshift -
quasars: absorption lines - quasars: emission lines - quasars: general
Abstract:
Outflows from active galactic nuclei are invoked as the principal
feedback process regulating the co-evolution of supermassive black
holes and their host galaxies. Because of their multi-phase and
multi-scale nature, an exhaustive description of these winds should
exploit multiple tracers. However, connecting various outflow features
remains a challenge. The aim of this work is to provide a complete
characterisation of outflows in a sample of z∼5 quasars, by exploiting
the combination of different emission and absorption tracers.
We analysed the UV/optical and FIR continuum, line emission, and
absorption in a sample of 39 z∼5 quasars observed with VLT/X-Shooter
and ALMA (available for six objects). We identified broad and narrow
absorption lines associated with the quasar and emission lines to
determine black hole masses and bolometric luminosities.
Our sample encompasses massive (MBH,MgII=108.5-10M☉) and
luminous (Lbol=1046.9-48erg/s) quasars at redshift 5∼5.7.
They display powerful ionised outflows detected in both emission and
absorption, with velocities exceeding 48000km/s in some cases, and lie
above the local black hole - host galaxy mass relation, exhibiting a
behaviour similar to that of z∼6 quasars. These findings suggest a
phase of efficient black hole feedback occurring at redshift
z∼6 and likely persisting down to z∼5, characterised by rapid
black hole growth exceeding that of the host galaxy. The fraction of
quasars with outflow detections in absorption is higher for larger
CIV-MgII velocity shifts, suggesting that while the physical
mechanisms powering the two outflow phenomena detected in emission and
absorption may differ, a correlation exists between them.
Description:
We consider 39 quasars at 4.99≲z≲5.70 observed using the X-Shooter
spectrograph at the Very Large Telescope (VLT). These objects are
retrieved from the programmes 098.A-0111 and 0100.A-0243 (PI:
Rafelski, M.), which were originally designed to conduct a blind
search for DLAs at z≳5, without any prior information on
intervening absorption systems.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
tablea1.dat 110 50 Properties of our sample of CIV absorption systems
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tablea1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Quasar Quasar name
12- 16 F5.3 --- zem Emission redshift
18- 24 F7.5 --- CIVzabs Absorption redshift
26- 33 F8.3 km/s CIVvabs Velocity of the absorption system with
respect to zem
35- 42 F8.6 0.1nm EW(CIV)r CIV rest equivalent width
44- 51 F8.6 0.1nm e_EW(CIV)r CIV rest equivalent width error
53- 59 F7.4 [cm-2] logN(CIV) Logarithm of CIV absorbers column density
61- 68 F8.6 [cm-2] e_logN(CIV) Error on CIV column density
70 I1 --- FlagNV [0/1] 1 if an associated NV absorption is
detected, 0 otherwise
72- 79 F8.4 [cm-2] logN(NV) ?=-1 Logarithm of NV absorbers column
density, when detected, -1 otherwise
81- 89 F9.6 [cm-2] e_logN(NV) ?=-1 Error on NV column density
91 I1 --- FlagSiIV [0/1] 1 if an associated SiIV absorption is
detected, 0 otherwise
93-100 F8.4 [cm-2] logN(SiIV) ?=-1 Logarithm of SiIV absorbers column
density, when detected, -1 otherwise
102-110 F9.6 [cm-2] e_logN(SiIV) ?=-1 Error on SiIV column density
--------------------------------------------------------------------------------
Acknowledgements:
Matilde Brazzini, matilde.brazzini(at)inaf.it
(End) Patricia Vannier [CDS] 18-Apr-2025