Speaker
Description
As the stellar analogs of extragalactic quasars, microquasars have been recognized as powerful Galactic particle accelerators that emit gamma rays exceeding multi-TeV energies since the first detection of SS 433. Interest in these objects has surged over the last decade. Recently, several have been observed emitting gamma rays above tens of TeV. The High Altitude Water Cherenkov (HAWC) observatory previously reported gamma-ray emissions with a median energy of 25 TeV from SS 433, demonstrating that gamma-ray binaries can accelerate particles to over 100 TeV within their jets. Utilizing approximately 2400 days of data and improved reconstruction algorithms (Pass5), HAWC detected emissions above 20 TeV from two additional binaries, V4641 Sagittarii and LS 5039. V4641 Sgr, in particular, has been detected with a significance greater than 9 sigma. It features a 6.4 solar mass black hole and a main sequence B-type companion of about 2.9 solar masses, notable for its super-Eddington accretion and one of the fastest superluminal radio jets in the Milky Way. In this presentation, I will share preliminary results from the study of these three microquasars in HAWC's data, including V4641 Sgr, and explore potential mechanisms for gamma-ray production. Additionally, I will outline future efforts to identify more X-ray binaries using HAWC
