The 3.8m optical and infrared telescope, which is Japan's first segmented mirror telescope, is now being constructed using the world's first super high...
Lens parameters for Gaia18cbf - a long gravitational microlensing event in the Galactic plane
Context. The timescale of a microlensing event scales as a square root of a lens mass. Therefore, long-lasting events are important candidates for massive...
M31GC J004234+405709 (Bol 117) Observed by Chandra Is a New Transient X-Ray Source in M31: CXOM31 J004234.2+405709
In ATel #1815 we erroneously associated the globular cluster M31GC J004234+405709 (Bol 117) with object s1-1 from Williams et al. (2006, ApJ 643, 356). Bol 117...
Magnitudes of X-ray Nova XTE J1650-500 in Quiescence
Observations of the optical counterpart to XTE J1650-500 with the Magellan 1 telescope find it fainter than expected based on reports of it's possible detection...
Mass Measurements of Stellar and Intermediate-Mass Black Holes
We discuss the method, and potential systematic effects therein, used for measuring the mass of stellar-mass black holes in X-ray binaries. We restrict our...
Mass Ratio Determination from H α Lines in Black Hole X-Ray Transients
We find that the mass ratio q in quiescent black hole (BH) X-ray transients is tightly correlated with the ratio of the double-peak separation (DP) to the full...
MASTER Optical Polarization Variability Detection in the Microquasar V404 Cyg/GS 2023+33
On 2015 June 15, the Swift space observatory discovered that the Galactic black hole candidate V404 Cyg was undergoing another active X-ray phase, after 25...
We report on a pointed RXTE/PCA observation of the transient source MAXI J1659-152 (Atel #2873,#2874,#2875,#2877,#2880 GCN #11296,#11299, #11307 - initially...
An astrophysical black hole is completely described with just two parameters: its mass and its dimensionless spin. A few dozen black holes have mass estimates...