We present the results of a multifrequency campaign on the high-redshift (z =
3.1) blazar PKS 0537-286. The source was observed at different epochs from 2006
to 2008 with INTEGRAL and Swift, and nearly simultaneously with ground-based
near-IR/optical telescopes. The SEDs are compatible with a model based on
synchrotron radiation and external inverse Compton scattering. The campaign
gives an insight into the physical environment of the blazar.Comment: 8 pages, 5 figures, accepted for publication in A&

Afonso, P.

Ajello, M.

Bottacini, E.

Cappelluti, N.

Covin, S.

Ghisellini, G.

Greiner, J.

Krühler, T.

Palazzi, E.

Pian, E.

Rau, A.

Yoldas, A. Küpcü

English

arXiv

BOTTACINI, EUGENIO ALESSIO

Covino, S.

Krühler, T.

Küpcü Yoldaş, A.

Archivio istituzionale della ricerca - Università di Padova

PKS 0537-286, carrying the information of the environment of SMBHs in the early universe

Context. The high-redshift (z = 3.1) blazar PKS 0537-286, belonging to the flat spectrum radio quasar blazar subclass, is one of the most luminous active galactic nuclei (AGN) in the Universe. Blazars are very suitable candidates for multiwavelength observations. Indeed, the relativistic beaming effect at work within the jet enhances their luminosity. This in turn allows the properties of the extragalactic jets, the powering central engine, and the surrounding environment to be derived. Aims. Our aim is to present the results of a multifrequency campaign from the near-IR to hard X-ray energies on PKS 0537-286 and give insight into the physical environment where the radiation processes take place. Methods. We observed the source at different epochs from 2006 to 2008 with INTEGRAL and Swift, and nearly simultaneously with ground-based optical telescopes. We also analyzed two archival spectra taken with XMM-Newton in 1999 and 2005. A comparative analysis of the results is performed. Results. The X-ray continuum of the blazar, as sampled by XMM, is described by a power law of index $\Gamma = 1.2$, modified by variable absorption at the soft X-rays, as found in other high-redshift QSOs. Modest X-ray continuum variability is found in the Swift observations. The combined Swift/BAT and Swift/XRT spectrum is very hard ($\Gamma = 1.3$). This, together with the non simultaneous EGRET detection and the more recent non detection by Fermi-LAT, constrains the peak of the high-energy component robustly. The optical/UV data, heavily affected by intervening Ly α absorption, indicate the presence of a bright thermal accretion disk that decreased in luminosity between 2006 and 2008. We infer from this a reduction of the BLR radius. When taking this into account, the 2006 and 2008 SEDs are compatible with a model based on synchrotron radiation and external inverse Compton scattering where the accretion-disk luminosity decreases between the 2 epochs by a factor 2, while the bulk Lorentz factor remains unchanged and the magnetic field changed only marginally

Bottacini, E

Ajello, M

Greiner, J

Pian, E

Rau, A

Palazzi, E

Covino, S

Ghisellini, G

Krühler, T

Küpcü Yoldaş, A

Cappelluti, N

Afonso, P

University of Miami: Scholarship Miami

Astronomy and Astrophysics

PKS 0537-286, carrying the information of the environment of SMBHs in the early Universe

E. Bottacini

M. Ajello

J. Greiner

E. Pian

A. Rau

E. Palazzi

S. Covino

G. Ghisellini

T. Krühler

A. Küpcü Yoldaş

N. Cappelluti

P. Afonso

Crossref

Context. The high-redshift (z = 3.1) blazar PKS 0537-286, belonging to the flat spectrum radio quasar blazar subclass, is one of the most luminous active galactic nuclei (AGN) in the Universe. Blazars are very suitable candidates for multiwavelength observations. Indeed, the relativistic beaming effect at work within the jet enhances their luminosity. This in turn allows the properties of the extragalactic jets, the powering central engine, and the surrounding environment to be derived.
        Aims. 
Our aim is to present the results of a multifrequency campaign from the near-IR to hard X-ray energies on PKS 0537-286 and give insight into the physical environment where the radiation processes take place.
        Methods. 
We observed the source at different epochs from 2006 to 2008 with INTEGRAL and Swift, and nearly simultaneously with ground-based optical telescopes. We also analyzed two archival spectra taken with XMM-Newton in 1999 and 2005. A comparative analysis of the results is performed.
        Results. 
The X-ray continuum of the blazar, as sampled by XMM, is described by a power law of index $\Gamma = 1.2$, modified by variable absorption at the soft X-rays, as found in other high-redshift QSOs. Modest X-ray continuum variability is found in the Swift observations. The combined Swift/BAT and Swift/XRT spectrum is very hard 
($\Gamma = 1.3$). This, together with the non simultaneous EGRET detection and the more recent non detection by Fermi-LAT, constrains the peak of the high-energy component robustly. The optical/UV data, heavily affected by intervening Ly α absorption, indicate the presence of a bright thermal accretion disk that decreased in luminosity between 2006 and 2008. We infer from this a reduction of the BLR radius. When taking this into account, the 2006 and 2008 SEDs are compatible with a model based on synchrotron radiation and external inverse Compton scattering where the accretion-disk luminosity decreases between the 2 epochs by a factor 2, while the bulk Lorentz factor remains unchanged and the magnetic field changed only marginally

EDP Sciences OAI-PMH repository (1.2.0)

PKS 0537-286, carrying the information of the environment  of SMBHs in the early Universe

Küpcü Yoldas, A.

MPG.PuRe

Context. The high-redshift (z = 3.1) blazar PKS 0537-286, belonging to the flat spectrum radio quasar blazar subclass, is one of the

most luminous active galactic nuclei (AGN) in the Universe. Blazars are very suitable candidates for multiwavelength observations.

Indeed, the relativistic beaming effect at work within the jet enhances their luminosity. This in turn allows the properties of the

extragalactic jets, the powering central engine, and the surrounding environment to be derived.

Aims. Our aim is to present the results of a multifrequency campaign from the near-IR to hard X-ray energies on PKS 0537-286 and

give insight into the physical environment where the radiation processes take place.

Methods. We observed the source at different epochs from 2006 to 2008 with INTEGRAL and Swift, and nearly simultaneously with

ground-based optical telescopes. We also analyzed two archival spectra taken with XMM-Newton in 1999 and 2005. A comparative

analysis of the results is performed.

Results. The X-ray continuum of the blazar, as sampled by XMM, is described by a power law of index Γ = 1.2, modified by

variable absorption at the soft X-rays, as found in other high-redshift QSOs. Modest X-ray continuum variability is found in the Swift

observations. The combined Swift/BAT and Swift/XRT spectrum is very hard (Γ = 1.3). This, together with the non simultaneous

EGRET detection and the more recent non detection by Fermi-LAT, constrains the peak of the high-energy component robustly.

The optical/UV data, heavily affected by intervening Ly α absorption, indicate the presence of a bright thermal accretion disk that

decreased in luminosity between 2006 and 2008. We infer from this a reduction of the BLR radius. When taking this into account,

the 2006 and 2008 SEDs are compatible with a model based on synchrotron radiation and external inverse Compton scattering where

the accretion-disk luminosity decreases between the 2 epochs by a factor 2, while the bulk Lorentz factor remains unchanged and the

magnetic field changed only marginally

Küpcü Yoldaş, A.

Caltech Authors - Main

Space Sci.

http://authors.library.caltech.edu/17569/1/Bottacini2010p7151Astron_Astrophys.pdf

PKS 0537-286, carrying the information of the environment of SMBHs in
  the early Universe

PKS 0537-286, carrying the information of the environment of SMBHs in the early Universe

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