Speaker
Description
Currently a sample of 5 microquasars are reported by LHASSO to have ultrahigh-energies (UHE, above 100TeV) emissions which remains a puzzle for the mechanism underneath. Among this sample, evidences of jet-dominated X-ray emissions were revealed from MAXI J1820+070 during an outburst well observed by Insight-HXMT. Here we report similar properties found in Swift J1727.8–1613 from the joint Insight-HXMT observations, and Swift J1727.8–1613 may end up with the first sample to bridge the MAXI J1820+070 to the majority of other XRBs due to its peculiar correlation between the spectral index and the reflection fraction. Accordingly, an overall framework is likely built that the hard X-ray emissions of black hole XRBs are balanced between flat-hot inner flow (e.g. corona) and jet. In such a scenario, Swift J 1727.8-1613 serves as a possible candidate for LHASSO UHE XRB system, while the majority of other BHXRBs are also microquasars but with jets too weak to be detectable as LHASSO UHE systems.
| Contribution | Oral talk |
|---|---|
| Affiliation | Institute of High Energy Physics, CAS, Beijing, China |
| szhang@mail.ihep.ac.cn |
