3 papers
astro-ph.HE2025
The alternating 'changing-look' blazar OQ 334 (B2 1420+32): New observational clues to the blazar state transitions
Krishan Chand, Gopal-Krishna
The high-luminosity blazar OQ 334 is a leading exponent of the intriguing rare phenomenon of alternating between a flat-spectrum radio quasar (FSRQ) and a BL Lac (BLL) states. Its…
astro-ph.GA2025
Weak-emission-line quasars: A new clue from their optical variability
Ritish Kumar, Gopal-Krishna, Hum Chand +1
Weak-emission-line QSOs (WLQs) are an enigmatic subclass of the QSO population, as their optical/UV spectra are marked by abnormally weak (or absent) emission lines. To obtain much…
astro-ph.GA2023
The transience and persistence of high optical polarization state in beamed radio quasars
Krishan Chand, Gopal-Krishna, Amitesh Omar +2
We examine the long-term stability (on decade-like time scales) of optical `high polarization' (HP) state with , which commonly occurs in flat-spectrum (i.e., beam…