Enhanced X-Ray Activity in the TeV-Detected Blazar of Unknown Redshift H1722+119
ATel #16103; Bidzina Kapanadze (Ilia State University, Tbilisi, Gerogia; E. Kharadze National Astrophysical Observatory, Abastumani, Georgia)
on 28 Jun 2023; 21:48 UT
Credential Certification: Bidzina Kapanadze (bidzina_kapanadze@iliauni.edu.ge)
Subjects: X-ray, AGN, Blazar
The high-energy peaked BL Lacertae (HBL) source of unknown redshift H1722+119 has been sparcely observed with Neil Gehrels Swift Observatory (only 22 times). In the framework of our target of opportunity (TOO) observations (Request Number 18965), the source was targeted on June 27 and the exposure with X-Ray Telescope onboard Swift (Swift-XRT) amounted to about 1.6 ks. Consequently, the source was found in the relatively elevated X-ray state corresponding to the 0.3-10 keV count rate of 66+/-0.05 cts/s. The latter is by factors of 2-3 higher than the count rates observed in the low X-ray states (see Kapanadze B. et al. 2023, Ap&SS, 368, 23). In the past, the source showed almost twice higher X-ray brightness in the flare peaks and strong optical-UV and gamma-ray variability (Kapanadze et al. 2023). Due to the opportunity to observe a further x-ray brightening and enhanced activity also in other spectral ranges (in the framework of one-zone synchrotron self-Compton model), we strongly encourage intense MWL observations with the space and ground-based instruments. XRT is one of the Swift instruments along with Burst Alert Telescope (BAT) and UV/Optical Telescope (UVOT). It is a JET-X Wolter I type telescope, developed jointly by Pennsylvania State University, Brera Astronomical Observatory (OAB) and University of Leicester. Thanks to the unique characteristics, good photon statistics and low background counts of this instrument (in combination with EEV CCD2 detector), we can investigate a flux variability on different time-scales from minutes to years, obtain high-quality spectra for the majority of the observations, derive different spectral parameters, and study their timing behaviour in the 0.3-10 keV range of the electromagnetic spectrum. The Swift Satellite is operated by Pennsylvania State University.
