The Properties of Quasar Hosts at the Peak of the Quasar Activity

Kotilainen, Jari; Falomo, R.; Decarli, Roberto; Treves, A.; Uslenghi, M.; Scarpa, Riccardo

doi:10.1088/0004-637x/703/2/1663

Cited by 32 publications

(58 citation statements)

References 73 publications

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“…One source of information about the cosmic structures at high redshifts is the distribution of quasars. Quasars lie at centres of massive galaxies (Hutchings et al 2002;Kotilainen et al 2009;Padmanabhan et al 2009;Letawe et al 2010;Kotilainen et al 2013;Falomo et al 2013;Floyd et al 2013;Falomo et al 2014;Karhunen et al 2014, and references therein), which typically lie in small groups and poor clusters of galaxies (Wold et al 2000;Soechting et al 2002;Söchting et al 2004;Coldwell & Lambas 2006;Hutchings et al 2009;Trainor & Steidel 2012;Ueda et al 2013). Nearby quasars are typically located in a relatively lowdensity, large-scale environment near superclusters of galaxies (Coldwell & Lambas 2006;Lietzen et al 2009Lietzen et al , 2011.…”

Section: Introductionmentioning

confidence: 99%

Tracing a high redshift cosmic web with quasar systems

Einasto

Tago

Lietzen

et al. 2014

A&A

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Context. To understand the formation, evolution, and present-day properties of the cosmic web we need to study it at low and high redshifts. Aims. We trace the cosmic web at redshifts that range from 1.0 ≤ z ≤ 1.8 by using the quasar (QSO) data from the SDSS DR7 QSO catalogue. Methods. We apply a friend-of-friend algorithm to the quasar and random catalogues to determine systems at a series of linking length and analyse richness and sizes of these systems. Results. At the linking lengths l ≤ 30 h −1 Mpc, the number of quasar systems is larger than the number of systems detected in random catalogues, and the systems themselves have smaller diameters than random systems. The diameters of quasar systems are comparable to the sizes of poor galaxy superclusters in the local Universe. The richest quasar systems have four members. The mean space density of quasar systems, ≈10−7 (h −1 Mpc) −3 , is close to the mean space density of local rich superclusters. At intermediate linking lengths (40 ≤ l ≤ 70 h −1 Mpc), the richness and length of quasar systems are similar to those derived from random catalogues. Quasar system diameters are similar to the sizes of rich superclusters and supercluster chains in the local Universe. The percolating system, which penetrate the whole sample volume appears in a quasar sample at a smaller linking length than in random samples (85 h −1 Mpc). At the linking length 70 h −1 Mpc, the richest systems of quasars have diameters exceeding 500 h −1 Mpc. Quasar luminosities in systems are not correlated with the system richness. Conclusions. Quasar system catalogues in our web pages and at the Strasbourg Astronomical Data Center (CDS) serve as a database for searching superclusters of galaxies and for tracing the cosmic web at high redshifts.

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Section: Introductionmentioning

confidence: 99%

Tracing a high redshift cosmic web with quasar systems

Einasto

Tago

Lietzen

et al. 2014

A&A

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show abstract

“…One source of information about the cosmic structures at high redshifts is the distribution of quasars. Quasars lie at centres of massive galaxies (Hutchings et al 2002; Send offprint requests to: M. Einasto Kotilainen et al 2009;Padmanabhan et al 2009;Letawe et al 2010;Kotilainen et al 2013;Falomo et al 2013;Floyd et al 2013;Falomo et al 2014;Karhunen et al 2014a, and references therein), being members of galaxy systems, usually small groups and poor clusters (Wold et al 2000;Soechting et al 2002;Söchting et al 2004;Coldwell & Lambas 2006;Hutchings et al 2009;Trainor & Steidel 2012;Ueda et al 2013). Nearby quasars are typically located in a relatively low-density large-scale environment near superclusters of galaxies (Coldwell & Lambas 2006;Lietzen et al 2009Lietzen et al , 2011.…”

Section: Introductionmentioning

confidence: 99%

Tracing high redshift cosmic web with quasar systems

Einasto¹

2014

Proc. IAU

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Context. To understand the formation, evolution, and present-day properties of the cosmic web we need to study it at low and high redshifts. Aims. We trace the cosmic web at redshifts 1.0 ≤ z ≤ 1.8 using the quasar (QSO) data from the SDSS DR7 QSO catalogue (Schneider et al. 2010). Methods. We apply a friend-of-friend (FoF) algorithm to the quasar and random catalogues to determine systems at a series of linking lengths, and analyse richness and sizes of these systems. Results. At the linking lengths l ≤ 30 h −1 Mpc the number of quasar systems is larger than the number of systems detected in random catalogues, and systems themselves have smaller diameters than random systems. The diameters of quasar systems are comparable to the sizes of poor galaxy superclusters in the local Universe, the richest quasar systems have four members. The mean space density of quasar systems, ≈ 10 −7 (h −1 Mpc) −3 , is close to the mean space density of local rich superclusters. At intermediate linking lengths (40 ≤ l ≤ 70 h −1 Mpc) the richness and length of quasar systems are similar to those derived from random catalogues. Quasar system diameters are similar to the sizes of rich superclusters and supercluster chains in the local Universe. The percolating system which penetrate the whole sample volume appears in quasar sample at smaller linking length than in random samples (85 h −1 Mpc). At the linking length 70 h −1 Mpc the richest systems of quasars have diameters exceeding 500 h −1 Mpc, three systems in our catalogue are the same as described in Clowes et al. (2012Clowes et al. ( , 2013. Quasar luminosities in systems are not correlated with the system richness. Conclusions. Quasar system catalogues at our web pages serve as a database to search for superclusters of galaxies and to trace the cosmic web at high redshifts.

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“…They find that the average Γ is higher than observed locally, consistent with the trend observed in our 38 J. K. Kotilainen et al study. Jahnke et al (2009) observed 10 targets with HST and independently derived host galaxy luminosities with a procedure similar to that adopted here (see, e.g., Kotilainen et al 2009). They find no evolution in the total M BH -M host ratio.…”

Section: Comparison With Previous Resultsmentioning

confidence: 99%

“…On the other hand, the nuclei in quasars outshine the emission from the host galaxies, making their detection challenging. Only recently have the intrinsic (e.g., the nucleus-to-host luminosity ratio N/H) and extrinsic (e.g., the angular size of the host with respect to the angular resolution of the observations) limitations have been overcome, with the current total of ∼ 300 resolved quasar host galaxies up to z ∼ 3 (e.g., Kotilainen et al 2009).…”

mentioning

confidence: 99%

Co-Evolution of Supermassive Black Holes and Their Host Galaxies

et al. 2009

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Abstract.We study the evolution of the MBH /M h ost relation up to z = 3 for a sample of 96 quasars with known host galaxy luminosities. Black hole masses are estimated assuming virial equilibrium in the broad-line regions, while the host galaxy masses are inferred from their luminosities. With this data, we are able to pin down the evolution of the M B H /M h ost relation over 85% of the age of the universe. While the MBH /L h ost relation remains nearly unchanged, taking into account the aging of the stellar population, we find that the MBH /M h ost ratio (Γ) increases by a factor ∼ 7 from z = 0 to z = 3. We show that the evolution of Γ is independent of radio loudness and quasar luminosity. We propose that the most massive black holes, in their quasar phase at high-redshift, become extremely rare objects in host galaxies of similar mass in the local universe.

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The Properties of Quasar Hosts at the Peak of the Quasar Activity

Cited by 32 publications

References 73 publications

Tracing a high redshift cosmic web with quasar systems

Tracing a high redshift cosmic web with quasar systems

Tracing high redshift cosmic web with quasar systems

Co-Evolution of Supermassive Black Holes and Their Host Galaxies

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