The impact of plasma instabilities on the spectra of TeV blazars

Autor(es)

Batista, Rafael Alves ^[1] ; Saveliev, Andrey ^{[2, 3]} ; de Gouveia Dal Pino, Elisabete M. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Astron Geofis & Ciencias Atmosfer, BR-05508090 Sao Paulo, SP - Brazil

^[2] Immanuel Kant Baltic Fed Univ, Inst Phys Math & Informat Technol, Kaliningrad 236041 - Russia

^[3] Lomonosov Moscow State Univ, Fac Computat Math & Cybernet, Moscow 119991 - Russia

• Tipo de documento: Artigo Científico
• Fonte: Monthly Notices of the Royal Astronomical Society; v. 489, n. 3, p. 3836-3849, NOV 2019.
• Citações Web of Science: 0

Resumo

Relativistic jets from blazars are known to be sources of very high energy gamma rays (VHEGRs). During their propagation in the intergalactic space, VHEGRs interact with pervasive cosmological photon fields such as the extragalactic background light (EBL) and the cosmic microwave background (CMB), producing electron-positron pairs. These pairs can upscatter CMB/EBL photons to high energies via inverse Compton (IC) scattering, thereby continuing the cascade process. This is often used to set limits on intergalactic magnetic fields (IGMFs). However, the picture may change if plasma instabilities, arising due to the interaction of the pairs with the intergalactic medium (IGM), cool down the electrons/positrons faster than inverse Compton scattering. As a consequence, the kinetic energy lost by the pairs to the IGM could cause a hardening in the observed gamma-ray spectrum at energies below similar to 100 GeV. Here, we study several types and models of instabilities and assess their impact for interpreting observations of distant blazars. Our results suggest that plasma instabilities can describe the spectra of some blazars and mimic the effects of IGMFs, depending on parameters such as intrinsic spectrum of the object, the density and temperature of the IGM, and the luminosity of the beam. On the other hand, we find that for our fiducial set of parameters plasma instabilities do not have a major impact on the spectra of some of the blazars studied. Therefore, they may be used for constraining IGMFs. (AU)

• Processo FAPESP: 17/12828-4 - Difusão, aceleração e propagação de raios cósmicos em ambientes astrofísicos turbulentos
• Beneficiário: Rafael Alves Batista
• Linha de fomento: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 13/10559-5 - Investigação de fenômenos de altas energias e plasmas astrofísicos: teoria, simulações numéricas, observações e desenvolvimento de instrumentação para o Cherenkov Telescope Array (CTA)
• Beneficiário: Elisabete Maria de Gouveia Dal Pino
• Linha de fomento: Auxílio à Pesquisa - Temático