Fermi-LAT Detection of TCP J18573095+1653396 (=Nova Her 2021)
ATel #14705; Kwan-Lok Li (NCKU)
on 13 Jun 2021; 07:50 UT
Credential Certification: K. L. Li (lilirayhk@gmail.com)
Subjects: Gamma Ray, Nova
Nova Her 2021 was discovered at 8.4 mag on 2021-06-12.537UT by Seiji Ueda (CBAT link). On 2021-06-12.90 UT, it reached R=5.7 mag and optical spectroscopic observations suggested that it is consistent with a nova with high-speed ejecta (Atel #14704). Using the Fermi-LAT data of 0.1-300GeV taken from 2021-6-12 00:00:00UT to 2021-6-12 23:36:56UT, we found an uncatalogued gamma-ray source at the nova position with TS=217 (equivalent to a detection significance of 14.7 sigma). Assuming a simple power-law model, the best-fit photon index is 2.8+/-0.1 and the inferred flux is F(0.1-300GeV) is (5.5+/-0.6)e-6 photons/cm^2/s or (2.0+/-0.2)e-9 erg/cm^2/s.
Multi-wavelength observations are strongly encouraged.