Search for the X-ray counterpart to IceCube-211216A event with Swift
ATel #15122; Rukaiya Khatoon (Tezpur Univ., IUCAA, India), Raj Prince (CFT, Poland), Ranjeev Misra (IUCAA, India)
on 17 Dec 2021; 13:54 UT
Credential Certification: Aditi Agarwal (aditiagarwal.phy@gmail.com)
Subjects: Optical, Ultra-Violet, X-ray, AGN, Blazar
On 2021-12-16 at 07:07:38.13 UT, IceCube detected a track-like event with a moderate probability of being of astrophysical origin (GCN #31241). The event was selected by the ICECUBE_Astrotrack_Bronze alert stream. Two gamma-ray sources listed in the 4FGL Fermi-LAT catalog are located in the 90% containment region.
We performed a search for the X-ray counterpart of the IceCube-211216A (GCN #31241) event. The observation in Swift was conducted for the two 4FGL sources, 4FGL J2100.0+1445 (R.A = 315.02 deg, Dec. = 14.76 deg) and 4FGL J2108.5+1434 (R.A = 317.15, Dec. = 14.58), located in the 90% containment region with their position 1.43 deg and 1.61 deg away from the best-fit IceCube-211216A event position. The observation by Swift was performed on 2021 December 16 at 15:34:03(UT) for 4FGL J2100.0+1445 (observation ID: 00014987001) and at 16:06:05(UT) for 4FGL J2108.5+1434 (observation ID: 00014988001) with an exposure of ~ 2.0 ks for each source.
With the preliminary analysis results using the Swift-XRT data, we observed that the source is too faint to extract the Swift-XRT spectrum. The GCN circular (GCN #31243) has also reported that there is no gamma-ray counterpart detected using combined all-sky detectors in INTEGRAL. Further, no ongoing muon neutrino candidate events were recorded by ANTARES (ATel #15121).
The Swift-UVOT observation was performed with U band filter. We do not observe any bright source at the source location.
We would like to thank the Swift Team for the extremely rapid and efficient scheduling of the ToO observation.