TY - JOUR
T1 - Host galaxies of high-redshift extremely red and obscured quasars
AU - Zakamska, Nadia L.
AU - Sun, Ai Lei
AU - Strauss, Michael A.
AU - Alexandroff, Rachael M.
AU - Brandt, W. N.
AU - Chiaberge, Marco
AU - Greene, Jenny E.
AU - Hamann, Fred
AU - Liu, Guilin
AU - Perrotta, Serena
AU - Ross, Nicholas P.
AU - Wylezalek, Dominika
N1 - Funding Information:
NLZ acknowledges support by the Catalyst Award at Johns Hopkins University and by the Deborah Lunder and Alan Ezekowitz Founders’ Circle Membership at the Institute for Advanced Study where part of this work was conducted. WNB acknowledges support by the NASA ADP program and NSF grant AST-1516784. GL is supported by the National Thousand Young Talents Program of China and acknowledges the grant from the National Natural Science Foundation of China (No. 11673020 and No. 11421303) and the Ministry of Science and Technology of China (National Key Program for Science and Technology Research and Development, No. 2016YFA0400700). NPR acknowledges support from the STFC and the Ernest Rutherford Fellowship scheme.
Funding Information:
Based on observations made with the NASA/ESA HST, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with programmes GO-14608 and GO-13014. Support for these programmes was provided by NASA through grants HST-GO-14608 and HST-GO-13014 from the STScI. NLZ acknowledges support by the Catalyst Award at Johns Hopkins University and by the Deborah Lunder and Alan Ezekowitz Founders' Circle Membership at the Institute for Advanced Study where part of this work was conducted. WNB acknowledges support by the NASA ADP program and NSF grant AST-1516784. GL is supported by the National Thousand Young Talents Program of China and acknowledges the grant from the National Natural Science Foundation of China (No. 11673020 and No. 11421303) and the Ministry of Science and Technology of China (National Key Program for Science and Technology Research and Development, No. 2016YFA0400700). NPR acknowledges support from the STFC and the Ernest Rutherford Fellowship scheme.
Funding Information:
Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with programmes GO-14608 and GO-13014. Support for these programmes was provided by NASA through grants HST-GO-14608 and HST-GO-13014 from the STScI.
Publisher Copyright:
© 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society
PY - 2019/10/11
Y1 - 2019/10/11
N2 - We present Hubble Space Telescope 1.4-1.6 μm images of the hosts of 10 extremely red quasars (ERQs) and six type 2 quasar candidates at z = 2-3. ERQs, whose bolometric luminosities range between 1047 and 1048 erg s−1, show spectroscopic signs of powerful ionized winds, whereas type 2 quasar candidates are less luminous and show only mild outflows. After performing careful subtraction of the quasar light, we clearly detect almost all host galaxies. The median rest-frame B-band luminosity of the ERQ hosts in our sample is 1011.2 L☉, or ∼4L∗ at this redshift. Two of the 10 hosts of ERQs are in ongoing mergers. The hosts of the type 2 quasar candidates are 0.6 dex less luminous, with 2/6 in likely ongoing mergers. Intriguingly, despite some signs of interaction and presence of low-mass companions, our objects do not show nearly as much major merger activity as do high-redshift radio-loud galaxies and quasars. In the absence of an overt connection to major ongoing gas-rich merger activity, our observations are consistent with a model in which the near-Eddington accretion and strong feedback of ERQs are associated with relatively late stages of mergers resulting in early-type remnants. These results are in some tension with theoretical expectations of galaxy formation models, in which rapid black hole growth occurs within a short time of a major merger. Type 2 quasar candidates are less luminous, so they may instead be powered by internal galactic processes.
AB - We present Hubble Space Telescope 1.4-1.6 μm images of the hosts of 10 extremely red quasars (ERQs) and six type 2 quasar candidates at z = 2-3. ERQs, whose bolometric luminosities range between 1047 and 1048 erg s−1, show spectroscopic signs of powerful ionized winds, whereas type 2 quasar candidates are less luminous and show only mild outflows. After performing careful subtraction of the quasar light, we clearly detect almost all host galaxies. The median rest-frame B-band luminosity of the ERQ hosts in our sample is 1011.2 L☉, or ∼4L∗ at this redshift. Two of the 10 hosts of ERQs are in ongoing mergers. The hosts of the type 2 quasar candidates are 0.6 dex less luminous, with 2/6 in likely ongoing mergers. Intriguingly, despite some signs of interaction and presence of low-mass companions, our objects do not show nearly as much major merger activity as do high-redshift radio-loud galaxies and quasars. In the absence of an overt connection to major ongoing gas-rich merger activity, our observations are consistent with a model in which the near-Eddington accretion and strong feedback of ERQs are associated with relatively late stages of mergers resulting in early-type remnants. These results are in some tension with theoretical expectations of galaxy formation models, in which rapid black hole growth occurs within a short time of a major merger. Type 2 quasar candidates are less luminous, so they may instead be powered by internal galactic processes.
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U2 - 10.1093/mnras/stz2071
DO - 10.1093/mnras/stz2071
M3 - Article
AN - SCOPUS:85081554822
VL - 489
SP - 497
EP - 516
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
SN - 0035-8711
IS - 1
ER -