9 papers
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…
X-rays breaking out of pre-explosion ejecta mark a supernova's first light
Weimin Yuan, Qiu-Ju Huang, Jin-Ping Zhu +130
Massive stars die as core-collapse supernovae, whose optical light emerges days after the implosion. Theory predicts that the initial collapse-driven shock, upon breaking through t…
Multiwavelength variability of the high-energy neutrino candidate PKS 0735+178 over three decades
T. Mufakharov, Yu. Sotnikova, V. Vlasyuk +12
We present the multiwavelength variability of the BL Lac object PKS 0735+178, associated with the high-energy neutrino event IC211208A. The light curves cover the radio (1-230 GHz)…
A fast X-ray transient with chromatic flares: signatures of violent collisions induced by late-time central engine reactivation
Shao-Yu Fu, Cui-Yuan Dai, Ai-Ling Wang +57
Extragalactic Fast X-ray Transients (EFXTs) represent an emerging class of high-energy phenomena characterized by X-ray outbursts lasting from tens to hundreds of seconds. However,…
Multi-messenger flare in the quasar PKS 0446+11
Y. Y. Kovalev, M. F. Aller, A. K. Erkenov +15
The physical mechanisms driving neutrino and electromagnetic flares in blazars remain poorly understood. We investigate a prominent multi-messenger flare in the quasar PKS 1424+240…
Photometric and late-time spectropolarimetric observations of GRB 250129A afterglow
A. Ghosh, S. Razzaque, J. Barnard +15
Gamma-Ray Burst (GRB) afterglows arise from the interaction of relativistic ejecta with the circumburst medium and are observed across the electromagnetic spectrum. Afterglow polar…