Fermi-LAT detection of the Galactic nova TCP J18102829-2729590
ATel #9699; Kwan-Lok Li and Laura Chomiuk (Michigan State University)
on 1 Nov 2016; 20:18 UT
Credential Certification: K. L. Li (lilirayhk@gmail.com)
Subjects: Gamma Ray, Nova
Referred to by ATel #: 9736
Fermi-LAT detection of the Galactic nova TCP J18102829-2729590
Following the discovery of the nova in Sagittarius TCP J18102829-2729590 (CBAT 2016 10 20.383; ATel #9658), we triggered an one-week Fermi ToO (observation number: 090603-1-1; PI: Laura Chomiuk) from 2016-10-25 as part of our Fermi-LAT monitoring campaign for Galactic novae (ATel #9311).
In the daily light curve from 2016-10-20 (i.e., the discovery date of the nova) to 2016-11-01 (until UT 12:56:35), a gamma-ray emission is marginally detected from 2016-10-28 with TS = 12 (TS = 3, 4, 5, 21 in the following days; photon index = -2.2 assumed). A binned likelihood analysis with the data between 2016-10-28 and 2016-11-01 (UT 12:56:35) confirms the detection with a TS = 46 (equivalent to a detection significance of 6-7 sigma). The inferred photon flux is (2.6+/-0.7)x10^-7 ph/cm^2/s (100MeV-300GeV; errors are statistical only), which is comparable to that of the other Fermi-detected novae (i.e., ~10^-7 ph/cm^2/s; Fermi-LAT Collaboration 2014).
We will continue to monitor the nova with Fermi. Meanwhile, more multi-wavelength follow-up observations are strongly encouraged. We thank the Fermi-LAT team for scheduling these observations.
