Large NIR flare of the FSRQ 4C+27.50
ATel #16863; L. Carrasco, G. Escobedo, A. Porras, E. Recillas, L. Felix;(INAOE, Mexico)
on 11 Oct 2024; 17:08 UT
Credential Certification: LUIS CARRASCO (carrasco@inaoep.mx)
Subjects: Radio, Infra-Red, Optical, Gamma Ray, TeV, AGN, Blazar, Quasar
We report on the recent NIR brightening of Flat Spectrum Radio Quasar (FSRQ) 4C +27.50, also
known as 4FGL J2321.9+273. On September 22th, 2024 (JD2460575.9494), we found the object
undergoing a large outburst. The NIR fluxes in the JHK bands were: J=12.032+/-0.042
(JD2460575.9494), H=11.094+/-0.034(JD2460575.9430) and Ks=10.345+/-0.051 (JD2460575.9600).
While the NIR fluxes in the H band on JD2460240.8084 it was H=14.985+/-0.043. Hence, the object
has increased its luminosity in the H band by a factor of 36 in this lapse. Two days ago, on
JD2460592.8380, the object had decreased its brightness to fluxes, J=13.659+/-0.022, H=12.456+/-
0.028 and Ks=11.922+/-0.032. Our observations are carried out with CANICA a NIR camera on the
2.1m telescope at the Observatorio Astrofisico Guillermo Haro, which is operated by the National
Institute for Astrophysics, Optics and Electronics (INAOE, Mexico). We encourage further
multiwavelength observations.
