Gamma-ray predictions for the very massive colliding-wind binary HD 93129A

DEL PALACIO, S.; BOSCH-RAMON, V; ROMERO, GUSTAVO E; BENAGLIA, P

Congreso; 6th International Meeting on High Energy Gamma-Ray Astronomy; 2016

Colliding-wind binaries have long been expected to be a class of -ray sources; however, up to date only -Carinaehas been firmly confirmed as such, and recently WR 11 was also associated with a Fermi source. In this work we study thepossible high-energy emission arising from the binary stellar system HD 93129A, one of the most massive binaries in the Galaxy.This system presents non-thermal radio emission produced in the wind-collision region (WCR). We developed a broadband nonthermalradiative model for the WCR taking into account the evolution of the accelerated particles streaming along the shockedregion, their emission by dierent radiative processes, and the attenuation of this radiation propagating through the local matter andelectromagnetic fields. Our model is able to reproduce the radio data and it predicts that the non-thermal emission in hard X-raysand -rays from HD 93129A will increase in the near future, as the system approaches periastron. In particular, we show that forecient particle acceleration and low magnetic fields in the WCR, HD 93129A should be detected by Fermi in the next few years.