4 papers
X-ray polarization in the soft state of Cyg X-1
A. Niedzwiecki, M. Szanecki, A. Veledina +5
We aim to identify the physical mechanism responsible for the observed X-ray emission and polarization of Cyg X-1 in the soft state. We performed a detailed spectral analysis of X-…
Model dependence of XRISM black-hole spin constraints in Cyg X-1
Andrzej A. Zdziarski, Swadesh Chand, Michal Szanecki +2
We study the persistent black hole X-ray binary Cyg X-1, recently observed by XRISM Resolve and simultaneously by NICER and NuSTAR in its hard spectral state. We confirm the result…
The strong Fe K line and spin of the black-hole X-ray binary MAXI J1631-479
Andrzej A. Zdziarski, Swadesh Chand, Gulab Dewangan +5
We study the transient black hole binary MAXI J1631--479 in its soft spectral state observed simultaneously by the NICER and NuSTAR instruments. Its puzzling feature is the presenc…
Is the Spin of the Black Hole in GX 339-4 Negative?
Andrzej A. Zdziarski, Srimanta Banerjee, Michal Szanecki +2
We have studied the accreting black hole binary GX 339--4 using two highly accurate broad-band X-ray data sets in very soft spectral states from simultaneous NICER and NuSTAR obser…