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Redshift measurement of Fermi Blazars for the Cherenkov Telescope Array
- Source :
- PoS, 34th International Cosmic Ray Conference, 34th International Cosmic Ray Conference, Jul 2015, The Hague, Netherlands. pp.835, ⟨10.22323/1.236.0835⟩, AIP Conf.Proc., 6th International Symposium on High-Energy Gamma-Ray Astronomy, 6th International Symposium on High-Energy Gamma-Ray Astronomy, Jul 2016, Heidelberg, Germany. pp.050025, ⟨10.1063/1.4968971⟩, 34th International Cosmic Ray Conference, Jul 2015, The Hague, Netherlands. PoS, ICRC2015, pp.835, 2016, 〈10.22323/1.236.0835〉
- Publication Year :
- 2015
- Publisher :
- HAL CCSD, 2015.
-
Abstract
- Blazars are active galactic nuclei, and the most numerous High Energy (HE) and Very High Energy (VHE) gamma-ray emitters. Their optical emission is often dominated by non-thermal, and, in the case of BL Lacs, featureless continuum radiation. This renders the determination of their redshift extremely difficult. Indeed, as of today only about 50 % of gamma-ray blazars have a measured spectroscopic redshift. The knowledge of redshift is fundamental because it allows the precise modeling of the VHE emission and also of its interaction with the extragalactic background light (EBL). The beginning of the Cherenkov Telescope Array (CTA) operations in the near future will allow the detection of several hundreds of new BL Lacs. Using the first Fermi catalogue of sources above 10 GeV (1FHL), we performed simulations which demonstrate that at least half of the 1FHL BL Lacs detectable by CTA will not have a measured redshift. Indeed the organization of observing campaigns to measure the redshift of these blazars has been recognized as a necessary support for the AGN Key Science Project of CTA. Taking advantage of the recent success of an X-shooter GTO observing campaign, we thus devised an observing campaign to measure the redshifts of as many as possible of these candidates. The main characteristic of this campaign with respect to previous ones will be the use of higher resolution spectrographs and of 8 meter class telescopes. We are starting submitting proposals for these observations. In this paper we will briefly describe the selection of the candidates, the characteristics of these observation and the expected results.<br />Comment: 8 pages, 2 figures, In Proceedings of the 34th International Cosmic Ray Conference (ICRC2015), The Hague, The Netherlands. All CTA contributions at arXiv:1508.05894
- Subjects :
- High energy
Active galactic nucleus
Cherenkov Telescope Array
[ PHYS.ASTR ] Physics [physics]/Astrophysics [astro-ph]
Astrophysics::High Energy Astrophysical Phenomena
FOS: Physical sciences
Astrophysics
Astrophysics::Cosmology and Extragalactic Astrophysics
01 natural sciences
GLAST
VHE
spectrum
blazar
0103 physical sciences
optical
AGN
Blazar
010303 astronomy & astrophysics
Astrophysics::Galaxy Astrophysics
Physics
High Energy Astrophysical Phenomena (astro-ph.HE)
energy: high
ta115
010308 nuclear & particles physics
background
Resolution (electron density)
Astronomy
imaging
resolution
Gamma-ray astronomy
Galaxy
Redshift
Cherenkov counter
gamma ray: emission
Extragalactic background light
gamma ray: VHE
photon: background
galaxy
Astrophysics - High Energy Astrophysical Phenomena
redshift: measured
[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
upper limit
Fermi Gamma-ray Space Telescope
Subjects
Details
- Language :
- English
- Database :
- OpenAIRE
- Journal :
- PoS, 34th International Cosmic Ray Conference, 34th International Cosmic Ray Conference, Jul 2015, The Hague, Netherlands. pp.835, ⟨10.22323/1.236.0835⟩, AIP Conf.Proc., 6th International Symposium on High-Energy Gamma-Ray Astronomy, 6th International Symposium on High-Energy Gamma-Ray Astronomy, Jul 2016, Heidelberg, Germany. pp.050025, ⟨10.1063/1.4968971⟩, 34th International Cosmic Ray Conference, Jul 2015, The Hague, Netherlands. PoS, ICRC2015, pp.835, 2016, 〈10.22323/1.236.0835〉
- Accession number :
- edsair.doi.dedup.....a07475812a1760360f3d8eb45c49d015