Multiband photometric observations of the flat spectrum radio quasar 4C 38.41

ATel #12034; Aditi Agarwal, Avinash Singh, Brajesh Kumar (Indian Institute of Astrophysics, Bnagalore, India)
on 12 Sep 2018; 18:07 UT
Credential Certification: Aditi Agarwal (aditiagarwal.phy@gmail.com)

Tweet

Flat spectrum radio quasar 4C 38.41 (RA: 16h 35m 15.493s, Dec: +38d 08m 04.50s), also known as B2 1633+38, OS 356, 3EG J1635+3813, has recently been observed to experience an optical outburst and also displayed multiwavelength activity as reported by WEBT/GASP (ATel #12025), AGILE (ATel #12026), and Fermi LAT (ATel #12027). Following these reports, we monitored the target on September 11th, 2018 using the 2m Himalayan Chandra Telescope (HCT), located at Hanle and operated by the Indian Institute of Astrophysics, Bangalore. Data processing was done using concentric circular aperture photometry technique to get the instrumental magnitudes of the source and the comparison stars. Derived instrumental magnitudes were then calibrated using star B of the finding chart from the webpage: https://www.lsw.uni-heidelberg.de/projects/extragalactic/charts/1633+382.html. Preliminary analysis of the photometric data points indicates that on September 11, 2018, flux in B band was 16.48 +/- 0.005, V filter was 16.11 +/- 0.004 while in R band it was 15.66 +/- 0.005. Since the object is still in active state further multifrequency observations of the source are encouraged.

1633+382 (B2 1633+38, 4C 38.41, OS 356)