HADRONIC GAMMA-RAY PRODUCTION IN MICROQUASARS WITH EQUATORIAL WINDS

MARIANA ORELLANA; GUSTAVO E. ROMERO

REVISTA MEXICANA DE ASTRONOMíA Y ASTROFíSICA

REDALYC

Año: 2006 vol. 26 p. 145 - 146

0185-1101

Microquasars are accreting X-ray binary systems with non-thermal radio jets. When the primary is a high- mass early-type star, the compact object accretes from the stellar wind. In some cases, like LS I +61 303, the wind forms an equatorial disk and the secondary moves through it. In such a situation a strong interaction between the relativistic ow and the dense wind material is unavoidable and could result in the generation of high-energy emission. This is particularly interesting since microquasars have been recently con rmed to be high-energy -ray sources. We present here a hadronic model for gamma-ray production in this kind of systems, with a speci c application to the case of LS I +61 303. We calculate the gamma-ray emission originated in pp interactions between relativistic protons in the jet and cold protons from the wind. The emission from secondary electron-positron pairs is estimated as well. After taking into account opacity eects on the gamma- rays introduced by the different photons elds, we present high-energy spectral predictions that can be tested with the new generation Cherenkov telescopes like MAGIC and HESS.