Pulse profiles provide a powerful diagnostic of the emission geometry and radiative processes in accreting X-ray pulsars, but their observed shape is affected by instrumental properties. We demonstrate that the energy-dependent pulsed fraction can be used as a robust timing cross-calibration diagnostic to combine XMM-Newton/EPIC-pn and NuSTAR observations. Using a simultaneous observation of...
X-ray binaries with red supergiant companions (RSGs) are extremely rare, and probe a very short-lived phase of binary evolution, just before the system is expected to undergo a second supernova. eRASS J085039.9-421151 (also Swift J0850.8-4219) was detected as a persistent source in the eROSITA survey at a relatively lower luminosity of 1e35 erg/s. The source was subsequently followed-up by...
Gamma-ray binaries are high-mass systems characterized by spectral energy distributions that peak near 100 MeV. X-ray observations of these systems reveal no detected spectral lines; only upper limits on Fe Kα are reported. This line deficit may be intrinsic, originating from extreme plasma ionization, or pulsar-driven disruption of the circumstellar environment. From an instrumental...
High Mass X-Ray binaries are fascinating systems. They consist of an O/B-type donor and a compact object (neutron star or black hole) embedded in the donor’s dense stellar wind, often in a close orbit, where orbital geometry and variability can be exploited to map the circumstellar environment.
During the years, we analysed interesting individual systems and, at the same time, developed some...
