Description
Chair: H. Negoro (Nihon-u)
Since the start of the operation in 2009, MAXI has detected many outbursts from newly discovered and known Galactic black hole and neutron star X-ray binaries. They were promptly reported to the astronomical community over the world, which stimulated follow-up observations at various wavelengths. MAXI itself also provided unique long-term X-ray data covering their entire outburst periods,...
The X-ray transient MAXI J1810-222 was discovered by MAXI in 2018 and has been active ever since. A long, combined radio and X-ray monitoring campaign was performed with ATCA and Swift, respectively. It gas been identified as a black hole candidate, even though the highly unusual outburst behaviour and the absence of information regarding the distance or the donor leaves the nature of the...
In this study, we undertake a spectral-timing analysis of the black hole X-ray binary source GRS 1915+105 using simultaneous observations carried out by AstroSat and NICER. The source showed two flux levels (high and low), whose energy spectra can be described by the thermal comptonization of disk photons. The spectral parameters obtained by the joint fitting of SXT/LAXPC and NICER/LAXPC were...
Since the launch of MAXI 15 years ago, several considerable achievements have been reached in the field of Galactic accreting binary systems, especially in light of the extreme variability of their relativistic jets. These jets have now been recognized as vital component for energy transfer and angular momentum in black holes. Although the phenomenology is now rather well established, their...
MAXI is one of the most successful astronomy mission satellites which discovered 14 Galactic X-ray binaries to date. We studied the accretion flow properties of 7 black hole candidates (BHCs; such as MAXI J1659-152, MAXI J1836-194, MAXI J1543-564, MAXI J1535-571, MAXI J1348-630, MAXI J1813-095, MAXI J1910-057) using one of the generalized physical accretion flow models, namely Two-component...
MAXI J1631-479 was discovered on 2018 December 21 by MAXI, and exhibited a fast rise and exponential decay type of the outburst. After the low/hard state at the beginning of the outburst, the source underwent a variety of state transitions. The source, however, had been mostly in the high/soft state after about 100 days from the discovery until the X-ray flux decreased by about four orders of...
Black hole X-ray binaries (BHXRBs) undergo hard-soft-hard state during their outbursts. In the soft state, the energy spectrum is dominated by thermal emission from the accretion disk, which is thought to extend down to the innermost stable circular orbit. In contrast, during the hard state, the disk is truncated at a larger radius, and the spectrum is dominated by a comptonization component...
We report the X-ray timing results of the black hole candidate MAXI J1820+070 during its 2018 outburst using the Hard X-ray Modulation Telescope (Insight-HXMT) and Neutron Star Interior Composition Explorer Mission (NICER) observations. Low-frequency quasi-periodic oscillations (LFQPOs) are detected in the low/hard state and the hard intermediate state, which lasted for ∼90 days. Thanks to the...
