4 papers · 1 filter
A broadband outburst of the compact steep-spectrum quasar 3C 138 in 2024-2026
T. V. Mufakharov, Yu. V. Sotnikova, V. V. Vlasyuk +20
After several decades of relative quiescence, the compact steep-spectrum quasar 3C 138 entered an active phase in 2024-2026, exhibiting strong broadband flaring. We investigate its…
The Reawakening of 4U 1755-338 after 25 Years of Quiescence: Spectro-temporal Analysis Using Multi-instrument X-ray Data
Geethu Prabhakar, Samir Mandal
The black hole X-ray binary 4U 1755338 underwent an outburst in 2020 after 25 years of quiescence. The comprehensive spectral analysis revealed that the system has a low interst…
The 2025 outburst of IGR J17511-3057: timing and spectral insights from NICER and NuSTAR
A. Sanna, G. K. Jaisawal, T. E. Strohmayer +13
IGR J17511-3057 was observed in a new outburst phase starting in February 2025 and lasting at least nine days. We investigated the spectral and temporal properties of IGR J17511-30…
Traces of wobbling accretion disk in X-ray pulsar Her X-1 from observations of the ART-XC telescope of the SRG observatory
V. M. Revnivtsev, K. A. Postnov, S. V. Molkov +5
Long uninterrupted observations of the X-ray binary system Her X-1 were performed with the Mikhail Pavlinsky ART-XC telescope of the Spectrum-Röntgen-Gamma (SRG) X-ray Observatory…