Report on the NuEM-240926A AMON Alert
ATel #16848; Hugo Ayala (PSU)
on 5 Oct 2024; 19:11 UT
Credential Certification: Hugo Alberto Ayala Solares (hgayala@psu.edu)
On September 29th, 2024, the AMON group reported on a multi-messenger alert NuEM240926A (GCN #37614). The position of the event is found at (RA,Dec)=(149.97,46.22) deg with a 50%(90%) uncertainty region of 0.22 deg (0.41 deg). The position is close to the 4FGL source J0959.6+4606 located at (RA,Dec)=(149.89,46.10) deg, which is 0.14 deg away from the AMON alert.
Follow-up observations have been performed by MASTER (GCN #37686), IceCube (GCN #37686) and Swift-XRT(GCN #37643). MASTER observations found the blazar BZQJ0955+4532 switching from an off-state to an on-state. IceCube performed a follow-up on this blazar, doing a time window search of 4 weeks for additional track-like muon neutrino events but the data is consistent with background. This blazar is 1.27 deg away from the AMON position.
Follow-up observations from Swift-XRT showed 4 sources detected in the exposure centered at the AMON position. Two of these sources, were found to be inside the AMON coincidence alert and inside of the 4FGL source.
One of these X-ray sources seems to be the counterpart of a Seyfert I galaxy SDSSJ095909.51+460014.3 (149.789,46.003). The measured flux is consistent with archival values (New: 4.2 (+2.8, -1.8)x10-13 erg cm-2 s-1, Archival: 3.4 (+3.6, -1.6)x10-13 erg cm-2 s-1).
The second source is located at (RA, Dec) = (150.063,45.980) deg. No counterpart was found for this source.
Pena-Herazo et al. 2021, suggested that the counterpart of the 4FGL source is the radio galaxy 2MASX J09591976+4603515. However the position of this source did not overlap with the X-ray sources.
New observations on these two X-ray sources will be performed to see if there is any fading or variability on them.
Observations of the AMON location are encouraged.
AMON seeks to perform a real-time correlation analysis of the
high-energy signals across all known astronomical messengers.
More information about AMON can be found in https://www.amon.psu.edu
Information on the IceCube collaboration: https://icecube.wisc.edu
Information on the HAWC collaboration: https://www.hawc-observatory.org
