//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 31451 SUBJECT: IceCube-220115A - IceCube observation of a high-energy neutrino candidate track-like event DATE: 22/01/15 14:17:17 GMT FROM: Marcos Santander at U. Alabama/IceCube The IceCube Collaboration (http://icecube.wisc.edu/) reports: On 2022-01-15 at 12:11:39.75 UT IceCube detected a track-like event with a moderate probability of being of astrophysical origin. The event was selected by the ICECUBE_Astrotrack_Bronze alert stream. The average astrophysical neutrino purity for Bronze alerts is 30%. This alert has an estimated false alarm rate of 2.090 events per year due to atmospheric backgrounds. The IceCube detector was in a normal operating state at the time of detection. After the initial automated alert (https://gcn.gsfc.nasa.gov/notices_amon_g_b/136170_48281000.amon), more sophisticated reconstruction algorithms have been applied offline, with the direction refined to: Date: 2022-01-15 Time: 12:11:39.75 UT RA: 357.45 (+1.75, -1.18 deg 90% PSF containment) J2000 Dec: 25.28 (+1.03, -0.95 deg 90% PSF containment) J2000 We encourage follow-up by ground and space-based instruments to help identify a possible astrophysical source for the candidate neutrino. There are no Fermi 4FGL or 3FHL catalog sources in the 90% uncertainty region. The nearest gamma-ray source in either catalog is 4FGL J2354.1+2720 at RA: 358.53 deg, Dec: 27.35 deg (2.28 deg away from the best-fit event position). The IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 31456 SUBJECT: IceCube Alert 220115.51: Global MASTER-Net observations report DATE: 22/01/15 20:13:07 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, G.Antipov, D.Zimnukhov, V.Senik, T.Pogrosheva, E.Minkina, A.Chasovnikov, V.Topolev, V.Grinshpun, D.Kuvshinov, D. Cheryasov (Lomonosov Moscow State University, SAI, Physics Department), R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA), R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias), D. Buckley (South African Astronomical Observatory), O.A. Gres, N.M. Budnev (Irkutsk State University, API), B.L.Carrasco, J.R.Valdes,V.Chavushyan, C.J.Martinez, V.M.Patino Alvarez, M.L.H.Rodriguez (INAOE, OAGH) A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), A. Gabovich, V.Yurkov (Blagoveschensk Educational State University) MASTER-IAC robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Spain (IAC Teide Observatory) was pointed to the IceCube Alert 220115.51 (trigger No 48281000,23h 49m 18.48s , +25d 07m 30.0s, R=0.51) errorbox 27563 sec after notice time and 27617 sec after trigger time at 2022-01-15 19:51:57 UT, with upper limit up to 18.4 mag. The observations began at zenith distance = 36 deg. The sun altitude is -18.1 deg. The galactic latitude b = -36 deg., longitude l = 106 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1850329 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 27708 | 2022-01-15 19:51:57 | MASTER-IAC | (23h 46m 50.96s , +25d 01m 44.8s) | C | 180 | 18.4 | 27708 | 2022-01-15 19:51:57 | MASTER-IAC | (23h 47m 49.28s , +24d 56m 54.7s) | C | 180 | 18.0 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 31479 SUBJECT: Fermi-LAT Gamma-ray Observations of IceCube-220115A and detection of a new gamma-ray source, Fermi J2350.2+2620 DATE: 22/01/18 11:40:24 GMT FROM: Simone Garrappa at DESY S. Garrappa (DESY-Zeuthen), S. Buson (Univ. of Wuerzburg) and J. Sinapius (DESY-Zeuthen) on behalf of the Fermi-LAT collaboration: We report an analysis of observations of the vicinity of the high-energy IC220115A neutrino event (GCN 31451) with all-sky survey data from the Large Area Telescope (LAT), on board the Fermi Gamma-ray Space Telescope. The IceCube event was detected on 2022-01-15 12:11:39.75 UTC (T0) with J2000 position RA = 357.45 (+1.75, -1.18) deg, Decl. = 25.28 (+1.03, -0.95) deg 90% PSF containment. No cataloged gamma-ray sources are found within the 90% IC220115A localization error (The Fourth Fermi-LAT catalog DR2; The Fermi-LAT collaboration 2020, ApJS, 247, 33). We searched for the existence of intermediate (months to years) timescale emission from a new gamma-ray transient source. Preliminary analysis indicates no significant (>5sigma) new excess emission (> 100 MeV) at the the IC220115A best-fit position. Assuming a power-law spectrum (photon index = 2.0 fixed) for a point source at the IceCube best-fit position, the >100 MeV flux upper limit (95% confidence) is < 5.6-10 ph cm^-2 s^-1 for ~13-years (2008-08-04 / 2022-01-15 UTC), < 1.1e-8 (< 5.2e-8) ph cm^-2 s^-1 for a 1-month (1-day) integration time before T0. Within the 90% confidence localization of the neutrino, ~1.1 deg offset from the best-fit IC220115A position, a >4 sigma excess of gamma rays, Fermi J2350.2+2620 was detected in an analysis of the integrated LAT data (> 100 MeV) between 2008-08-04 and 2022-01-15. Assuming a power-law spectrum, the candidate gamma-ray source has best-fit localization (J2000) RA: 357.564, Dec: 26.343 (0.15 deg 99% containment, 0.07 deg 68% containment), with best-fit spectral parameters flux = (8 +/- 5)e-10 ph cm^-2 s^-1 and index = 2.0 +/- 0.2. In a preliminary analysis of the LAT data over one day and one month prior T0, Fermi J2350.2+2620 is not significantly detected in the LAT data. All values include the statistical uncertainty only. Since Fermi normally operates in an all-sky scanning mode, regular monitoring of this source will continue. For these observations the Fermi-LAT contact persons are S. Garrappa (simone.garrappa at desy.de) and S. Buson (sara.buson at uni-wuerzburg.de). The Fermi LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 31484 SUBJECT: IceCube-220115A: Upper limits from a search for additional neutrino events in IceCube DATE: 22/01/18 15:01:14 GMT FROM: Alex Pizzuto at ICECUBE/U of Wisconsin The IceCube Collaboration (http://icecube.wisc.edu/) reports: IceCube has performed a search [1] for additional track-like muon neutrino events arriving from the direction of IceCube-220115A (https://gcn.gsfc.nasa.gov/gcn3/31451.gcn3) in a time range of 1000 seconds centered on the alert event time (2022-01-15 12:03:19.750 UTC to 2022-01-15 12:19:59.750 UTC) during which IceCube was collecting good quality data. Excluding the event that prompted the alert, zero track-like events are found within the 90% containment region of IceCube-220115A. We find that these data are consistent with atmospheric background expectations, with a p-value of 0.013. The IceCube sensitivity to neutrino point sources with an E^-2.5 spectrum (E^2 dN/dE at 1 TeV) within the locations spanned by the 90% spatial containment region of IceCube-220115A is 1.4e-01 GeV cm^-2 in a 1000 second time window. 90% of events IceCube would detect from a source at this declination with an E^-2.5 spectrum have energies in the approximate energy range between 2e+02 GeV and 8e+04 GeV. A subsequent search was performed including 2 days of data centered on the alert event time (2022-01-14 12:11:39.750 UTC to 2022-01-16 12:11:39.750 UTC). In this case, we report a p-value of 1.00, consistent with no significant excess of track events. The IceCube sensitivity to neutrino point sources with an E^-2.5 spectrum (E^2 dN/dE at 1 TeV) within the locations spanned by the 90% spatial containment region of IceCube-220115A is 1.7e-01 GeV cm^-2 in a 2 day time window. The IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc@icecube.wisc.edu. [1] IceCube Collaboration, R. Abbasi et al., ApJ 910 4 (2021)