2015MNRAS.446.2483S

Query : 2015MNRAS.446.2483S

2015MNRAS.446.2483S - Mon. Not. R. Astron. Soc., 446, 2483-2489 (2015/January-3)

Blazar candidates beyond redshift 4 observed by Swift.

SBARRATO T., GHISELLINI G., TAGLIAFERRI G., FOSCHINI L., NARDINI M., TAVECCHIO F. and GEHRELS N.

Abstract (from CDS):

We have selected SDSS J222032.50+002537.5 and SDSS J142048.01+120545.9 as best blazar candidates out of a complete sample of extremely radio-loud quasars at z > 4, with highly massive black holes. We observed them and a third serendipitous candidate with similar features (PMN J2134-0419) in the X-rays with the Swift/XRT telescope, to confirm their blazar nature. We observed strong and hard X-ray fluxes (i.e. α_X  \lower.75ex∼ ///<   0.6, where F(ν)∝ν^-α_X in the 0.3-10 keV observed energy range, ∼ 1-40 keV rest frame) in all three cases. This allowed us to classify our candidates as real blazars, being characterized by large Lorentz factors ( ∼ 13) and very small viewing angles ( ∼ 3°). All three sources have black hole masses exceeding 109M☉ and their classification provides intriguing constraints on supermassive black hole formation and evolution models. We confirm our earlier suggestion that there are different formation epochs of extremely massive black holes hosted in jetted (z ∼ 4) and non-jetted systems (z ∼ 2.5).

Abstract Copyright: © 2014 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society (2014)

Journal keyword(s): radiation mechanisms: thermal - galaxies: active - quasars: general - X-rays: general

Simbad objects: 10

goto Full paper

goto View the references in ADS

Number of rows : 10
N Identifier Otype ICRS (J2000)
RA 		ICRS (J2000)
DEC 		Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2026 		#notes
1 [VV2006] J083946.1+511203 QSO 08 39 46.2164854008 +51 12 02.827270296   22.29 20.66 18.9 18.3 ~ 72 1
2 QSO J0906+6930 Bla 09 06 30.74874670 +69 30 30.8287169       21.65   ~ 96 1
3 7C 102336.6+255813 QSO 10 26 23.62115 +25 42 59.4292   24.98 23.18     ~ 86 1
4 QSO B1026-084 Bla 10 28 38.79646593 -08 44 38.5362663     21.00 19.6   ~ 77 1
5 QSO J1146+4037 QSO 11 46 57.7910518704 +40 37 08.602166820   24.80 22.78     ~ 60 0
6 SDSS J142048.01+120545.9 QSO 14 20 48.0094133568 +12 05 45.979158120   21.96 20.94     ~ 39 1
7 7C 1428+4218 Bla 14 30 23.74163471 +42 04 36.4910561   24.43 22.04 20.2   ~ 157 1
8 QSO B1508+572 QSO 15 10 02.92237321 +57 02 43.3759220   22.73 21.38 19.23   ~ 223 1
9 QSO J2134-0419 QSO 21 34 12.0103883184 -04 19 09.866519544     19.98     ~ 31 1
10 SDSS J222032.50+002537.5 QSO 22 20 32.5027007856 +00 25 37.508561724   23.9669 21.5403 20.2745 20.2655 ~ 39 1

To bookmark this query, right click on this link: simbad:objects in 2015MNRAS.446.2483S and select 'bookmark this link' or equivalent in the popup menu