TY - GEN
T1 - Prospect on intergalactic magnetic field measurements with gamma-ray instruments
AU - Sol, Hélène
AU - Zech, Andreas
AU - Boisson, Catherine
AU - Krawczynski, Henric
AU - Fallon, Lisa
AU - De Gouveia Dal Pino, Elisabete
AU - Hinton, Jim
AU - Inoue, Susumu
AU - Neronov, Andrii
AU - White, Richard
PY - 2012/8
Y1 - 2012/8
N2 - Observing high-energy gamma-rays from Active Galactic Nuclei (AGN) offers a unique potential to probe extremely tiny values of the intergalactic magnetic field (IGMF), a long standing question of astrophysics, astroparticle physics and cosmology. Very high energy (VHE) photons from blazars propagating along the line of sight interact with the extragalactic background light (EBL) and produce e + e - pairs. Through inverse-Compton interaction, mainly on the cosmic microwave background (CMB), these pairs generate secondary GeV-TeV components accompanying the primary VHE signal. Such secondary components would be detected in the gamma-ray range as delayed pair echos for very weak IGMF (B < 10-16 G), while they should result in a spatially extended gamma-ray emission around the source for higher IGMF values (B > 10-16 G). Coordinated observations with space (i.e. Fermi) and ground-based gamma-ray instruments, such as the present Cherenkov experiments H.E.S.S., MAGIC and VERITAS, the future Cherenkov Telescope Array (CTA) Observatory, and the wide-field detectors such as HAWC and LHAASO, should allow to analyze and finally detect such echos, extended emission or pair halos, and to further characterize the IGMF.
AB - Observing high-energy gamma-rays from Active Galactic Nuclei (AGN) offers a unique potential to probe extremely tiny values of the intergalactic magnetic field (IGMF), a long standing question of astrophysics, astroparticle physics and cosmology. Very high energy (VHE) photons from blazars propagating along the line of sight interact with the extragalactic background light (EBL) and produce e + e - pairs. Through inverse-Compton interaction, mainly on the cosmic microwave background (CMB), these pairs generate secondary GeV-TeV components accompanying the primary VHE signal. Such secondary components would be detected in the gamma-ray range as delayed pair echos for very weak IGMF (B < 10-16 G), while they should result in a spatially extended gamma-ray emission around the source for higher IGMF values (B > 10-16 G). Coordinated observations with space (i.e. Fermi) and ground-based gamma-ray instruments, such as the present Cherenkov experiments H.E.S.S., MAGIC and VERITAS, the future Cherenkov Telescope Array (CTA) Observatory, and the wide-field detectors such as HAWC and LHAASO, should allow to analyze and finally detect such echos, extended emission or pair halos, and to further characterize the IGMF.
KW - gamma-ray astronomy
KW - high-redshift blazars
KW - intergalactic space
KW - magnetic field
KW - pair echos
KW - pair halos
UR - https://www.scopus.com/pages/publications/84880524219
U2 - 10.1017/S1743921313002925
DO - 10.1017/S1743921313002925
M3 - Conference contribution
AN - SCOPUS:84880524219
SN - 9781107033832
T3 - Proceedings of the International Astronomical Union
SP - 459
EP - 470
BT - Solar and Astrophysical Dynamos and Magnetic Activity
A2 - Kosovichev, Alexander G.
A2 - de Gouveia Dal Pino, Elisabete
A2 - Yan, Yihua
ER -