High optical state of the Gamma-ray flaring PKS 0346-27
ATel #11269; Roberto Nesci (INAF/IAPS-Roma)
on 7 Feb 2018; 16:01 UT
Credential Certification: Roberto Nesci (Roberto.Nesci@iaps.inaf.it)
Subjects: Infra-Red, Optical, AGN, Quasar
The radio quasar PKS 0346-27 has been detected by Fermi-LAT in a very bright state (Angioni et al. ATel #11251) on February 2, 2018. I could observe the source with the REM Telescope at La Silla on February 7 (MJD 58156.08) in the r,i (Sloan), and J,H (Johnson) filters. Comparison stars were taken from the UCAC4 catalog for the r,i bands and 2MASS for the J,H bands.
The following magnitudes were measured: r=16.63+-0.07, i=16.12+-0.10, J=14.68 +-0.07, and H=13.85 +-0.06.
The quasar is therefore now about 2 magnitudes brighter than the 2MASS values, J=16.77 and H=16.31.
Optical, non simultaneous, DSS values from GSC2.3.2, converted to the r and i bands, were r=19.51 and i=14.76. In the USNO-B1 it is reported in the photographic N band (Cousins I) as faint as 18.45 indicating a large historic variability range.
It is likely that PKS0346-27 was even brighter at the time of the Gamma-ray flare. Monitoring with REM will continue in the next days.