//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 31832 SUBJECT: IceCube Alert 220405.21: Global MASTER-Net observations report DATE: 22/04/05 05:39:32 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, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin (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), L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), A. Gabovich, V.Yurkov (Blagoveschensk Educational State University) MASTER-OAGH robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Mexico (OAGH National Institute for Astrophysics, Optics and Electronics) was pointed to the IceCube Alert 220405.21 (trigger No 1833389,08h 58m 35.28s , -01d 13m 04.8s, R=0.65) errorbox 19 sec after notice time and 72 sec after trigger time at 2022-04-05 04:58:38 UT, with upper limit up to 18.4 mag. The observations began at zenith distance = 40 deg. The sun altitude is -39.7 deg. The galactic latitude b = 28 deg., longitude l = 230 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1933135 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 78 | 2022-04-05 04:58:38 | MASTER-OAGH | (08h 54m 34.29s , -01d 12m 46.4s) | C | 10 | 15.9 | 78 | 2022-04-05 04:58:38 | MASTER-OAGH | (08h 54m 07.08s , -00d 44m 08.9s) | P- | 10 | 15.7 | 114 | 2022-04-05 04:59:09 | MASTER-OAGH | (08h 54m 34.25s , -01d 13m 50.3s) | C | 20 | 16.7 | 114 | 2022-04-05 04:59:09 | MASTER-OAGH | (08h 54m 06.99s , -00d 45m 13.1s) | P- | 20 | 16.3 | 160 | 2022-04-05 04:59:51 | MASTER-OAGH | (08h 54m 36.30s , -01d 12m 32.0s) | C | 30 | 16.4 | 160 | 2022-04-05 04:59:51 | MASTER-OAGH | (08h 54m 09.03s , -00d 43m 55.0s) | P- | 30 | 16.5 | 216 | 2022-04-05 05:00:42 | MASTER-OAGH | (08h 54m 31.27s , -01d 13m 19.2s) | C | 40 | 16.6 | 216 | 2022-04-05 05:00:42 | MASTER-OAGH | (08h 54m 03.99s , -00d 44m 41.8s) | P- | 40 | 16.7 | 283 | 2022-04-05 05:01:44 | MASTER-OAGH | (08h 54m 31.23s , -01d 12m 20.0s) | C | 50 | 17.0 | 283 | 2022-04-05 05:01:44 | MASTER-OAGH | (08h 54m 03.93s , -00d 43m 43.1s) | P- | 50 | 17.0 | 365 | 2022-04-05 05:02:55 | MASTER-OAGH | (08h 54m 10.01s , -00d 44m 42.4s) | P- | 70 | 17.3 | 365 | 2022-04-05 05:02:55 | MASTER-OAGH | (08h 54m 37.35s , -01d 13m 21.0s) | C | 70 | 17.4 | 461 | 2022-04-05 05:04:27 | MASTER-OAGH | (08h 54m 31.37s , -01d 14m 20.8s) | C | 80 | 17.4 | 461 | 2022-04-05 05:04:27 | MASTER-OAGH | (08h 54m 03.99s , -00d 45m 43.0s) | P- | 80 | 17.5 | 572 | 2022-04-05 05:06:08 | MASTER-OAGH | (08h 54m 10.03s , -00d 45m 30.1s) | P- | 100 | 17.7 | 572 | 2022-04-05 05:06:08 | MASTER-OAGH | (08h 54m 37.47s , -01d 14m 08.1s) | C | 100 | 18.4 | 708 | 2022-04-05 05:08:09 | MASTER-OAGH | (08h 54m 34.63s , -01d 12m 46.2s) | C | 130 | 17.9 | 708 | 2022-04-05 05:08:09 | MASTER-OAGH | (08h 54m 07.11s , -00d 44m 08.2s) | P- | 130 | 17.8 | 878 | 2022-04-05 05:10:44 | MASTER-OAGH | (08h 54m 34.81s , -01d 14m 07.6s) | C | 160 | 17.7 | 878 | 2022-04-05 05:10:44 | MASTER-OAGH | (08h 54m 07.20s , -00d 45m 29.6s) | P- | 160 | 17.8 | 1070 | 2022-04-05 05:13:45 | MASTER-OAGH | (08h 54m 38.08s , -01d 12m 29.3s) | C | 180 | 18.2 | 1070 | 2022-04-05 05:13:45 | MASTER-OAGH | (08h 54m 10.33s , -00d 43m 51.1s) | P- | 180 | 17.9 | 1271 | 2022-04-05 05:17:07 | MASTER-OAGH | (08h 54m 32.31s , -01d 13m 24.8s) | C | 180 | 17.5 | 1271 | 2022-04-05 05:17:07 | MASTER-OAGH | (08h 54m 04.44s , -00d 44m 45.8s) | P- | 180 | 17.7 | 1473 | 2022-04-05 05:20:29 | MASTER-OAGH | (08h 54m 32.47s , -01d 12m 26.0s) | C | 180 | 17.9 | 1473 | 2022-04-05 05:20:29 | MASTER-OAGH | (08h 54m 04.49s , -00d 43m 47.4s) | P- | 180 | 17.7 | 1699 | 2022-04-05 05:24:14 | MASTER-OAGH | (08h 54m 38.79s , -01d 13m 25.9s) | C | 180 | 17.9 | 1699 | 2022-04-05 05:24:14 | MASTER-OAGH | (08h 54m 10.67s , -00d 44m 46.8s) | P- | 180 | 17.8 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 31833 SUBJECT: IceCube-220405A - IceCube observation of a high-energy neutrino candidate track-like event DATE: 22/04/05 08:53:19 GMT FROM: Dr. Massimiliano Lincetto at Ruhr-Universitaet Bochum The IceCube Collaboration (http://icecube.wisc.edu/) reports: On 2022-04-05 at 04:57:26.12 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 3.28 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/136504_1833389.amon), more sophisticated reconstruction algorithms have been applied offline, with the direction refined to: Date: 2022-04-05 Time: 04:57:26.12 UT RA: +134.47 (+1.71/-1.72 deg 90% PSF containment) J2000 Dec: -1.27 (+1.45/-1.02 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-DR3 or 3FHL catalog sources in the 90% uncertainty region. The nearest gamma-ray source in either catalog is 4FGL J0859.8+0053 at RA: 134.95 deg, Dec: 0.90 deg J2000 (2.22 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: 31836 SUBJECT: Fermi-LAT Gamma-ray Observations of IceCube-220405A DATE: 22/04/05 19:39:22 GMT FROM: Simone Garrappa at DESY S. Garrappa (DESY-Zeuthen) and S. Buson (Univ. of Wuerzburg) on behalf of the Fermi-LAT collaboration: We report an analysis of observations of the vicinity of the high-energy IC220405A neutrino event (GCN 31833) 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 2022-04-05 at 04:57:26.12  UT (T0) with J2000 position RA = +134.47 (+1.71, -1.72) deg, Decl. = -1.27 (+1.45, -1.02) deg (90% PSF containment). No cataloged gamma-ray (>100 MeV) sources are located within the 90% IC220405A localization region (4FGL-DR3; arXiv:2201.11184; The Fermi-LAT collaboration 2020, ApJS, 247, 33). We searched for intermediate (days to years) timescale emission from a new gamma-ray transient source. Preliminary analysis indicates no significant (> 5 sigma) new excess emission (> 100 MeV) at the IC220405A best-fit position. Assuming a power-law spectrum (photon index = 2.0 fixed) for a point source at the IC220405A best-fit position, the >100 MeV flux upper limit (95% confidence) is < 1.1e-10 ph cm^-2 s^-1 for ~13-years (2008-08-04 to 2022-04-05 UTC), and < 3.2e-9 (< 8.0e-8) ph cm^-2 s^-1 for a 1-month (1-day) integration time before T0. 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: 31839 SUBJECT: IceCube-220405A - IceCube observation of a high-energy neutrino candidate track-like event DATE: 22/04/06 02:12:43 GMT FROM: Erik Blaufuss at U. Maryland/IceCube The IceCube Collaboration (http://icecube.wisc.edu/) reports: On 2022-04-05 at 22:20:03.41 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 2.02 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/136506_15341152.amon), more sophisticated reconstruction algorithms have been applied offline, with the direction refined to: Date: 2022-04-05 Time: 22:20:03.41 UT RA: 320.62 (+1.37, -1.13 deg 90% PSF containment) J2000 Dec: 29.06 (+0.94, -0.68 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 sources in the 4FGL-DR2 Fermi-LAT catalog in the 90% uncertainty region. The nearest source is 4FGL J2115.4+2932 (318.87 deg, 29.55 deg J2000, 1.82 deg away from the best-fit neutrino 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: 31840 SUBJECT: IceCube Alert 220405.93: Global MASTER-Net observations report DATE: 22/04/06 02:39:31 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, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin (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), L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), A. Gabovich, V.Yurkov (Blagoveschensk Educational State University) MASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the IceCube Alert 220405.93 (trigger No 15341152,21h 21m 05.52s , +29d 16m 26.4s, R=0.57) errorbox 205 sec after notice time and 253 sec after trigger time at 2022-04-05 22:24:16 UT, with upper limit up to 17.5 mag. The observations began at zenith distance = 85 deg. The sun altitude is -39.0 deg. The galactic latitude b = -15 deg., longitude l = 78 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1934534 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 278 | 2022-04-05 22:24:16 | MASTER-Tavrida | (21h 10m 41.06s , +29d 20m 08.8s) | P\ | 50 | 14.1 | 442 | 2022-04-05 22:26:45 | MASTER-Tavrida | (21h 10m 38.14s , +29d 20m 14.9s) | P\ | 80 | 14.7 | 701 | 2022-04-05 22:30:39 | MASTER-Tavrida | (21h 10m 45.42s , +29d 18m 21.1s) | P\ | 130 | 14.4 | 860 | 2022-04-05 22:33:08 | MASTER-Tavrida | (21h 10m 47.13s , +29d 19m 16.8s) | P\ | 150 | 14.6 | 1045 | 2022-04-05 22:35:58 | MASTER-Tavrida | (21h 10m 52.69s , +29d 18m 09.4s) | P\ | 180 | 14.8 | 1244 | 2022-04-05 22:39:17 | MASTER-Tavrida | (21h 10m 48.09s , +29d 17m 04.5s) | P\ | 180 | 15.0 | 1444 | 2022-04-05 22:42:37 | MASTER-Tavrida | (21h 10m 54.31s , +29d 17m 03.1s) | P\ | 180 | 15.1 | 1643 | 2022-04-05 22:45:56 | MASTER-Tavrida | (21h 10m 51.07s , +29d 18m 55.0s) | P\ | 180 | 15.1 | 2921 | 2022-04-05 23:08:14 | MASTER-Tavrida | (21h 11m 46.38s , +29d 43m 16.3s) | C | 60 | 17.5 | 3900 | 2022-04-05 23:24:33 | MASTER-Tavrida | (21h 11m 54.18s , +29d 43m 52.9s) | C | 60 | 13.6 | 7168 | 2022-04-06 00:19:01 | MASTER-Tavrida | (21h 19m 24.68s , +31d 37m 22.4s) | C | 60 | 15.5 | 14033 | 2022-04-06 02:12:26 | MASTER-Tavrida | (21h 12m 01.83s , +29d 05m 55.1s) | P\ | 180 | 16.2 | 14232 | 2022-04-06 02:15:45 | MASTER-Tavrida | (21h 12m 00.56s , +29d 06m 58.0s) | P\ | 180 | 16.1 | 14432 | 2022-04-06 02:19:05 | MASTER-Tavrida | (21h 12m 07.54s , +29d 05m 59.7s) | P\ | 180 | 16.0 | 14632 | 2022-04-06 02:22:25 | MASTER-Tavrida | (21h 12m 01.54s , +29d 05m 01.3s) | P\ | 180 | 15.8 | 14771 | 2022-04-06 02:25:44 | MASTER-Tavrida | (21h 13m 49.18s , +27d 51m 07.0s) | C | 60 | 17.0 | 14930 | 2022-04-06 02:28:23 | MASTER-Tavrida | (21h 22m 54.58s , +27d 50m 38.8s) | C | 60 | 16.7 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 31843 SUBJECT: IceCube-220405A: No Candidate Counterparts from the Zwicky Transient Facility DATE: 22/04/06 15:33:18 GMT FROM: Simeon Reusch at DESY Simeon Reusch, Jannis Necker (DESY), Robert Stein (Caltech), Sven Weimann (Ruhr University Bochum) and Anna Franckowiak (DESY/Ruhr University Bochum), On behalf of the Zwicky Transient Facility (ZTF) and Global Relay of Observatories Watching Transients Happen (GROWTH) collaborations: As part of the ZTF neutrino follow up program (Stein et al. 2022), observed the localization region of the neutrino event IceCube-220405A (Lincetto et. al, GCN 31833) with the Palomar 48-inch telescope, equipped with the 47 square degree ZTF camera (Bellm et al. 2019, Graham et al. 2019). We started observations in the g- and r-band beginning at 2022-04-05 05:31 UTC, approximately 0.6 hours after event time. We covered 98.3% (7.5 sq deg) of the reported localization region. This estimate accounts for chip gaps. Two of the exposures lasted 300s, with a typical depth of 21.0 mag. The images were processed in real-time through the ZTF reduction and image subtraction pipelines at IPAC to search for potential counterparts (Masci et al. 2019). AMPEL (Nordin et al. 2019, Stein et al. 2021) was used to search the alerts database for candidates. We reject stellar sources (Tachibana and Miller 2018) and moving objects, and apply machine learning algorithms (Mahabal et al. 2019). No candidate counterparts were detected. ZTF and GROWTH are worldwide collaborations comprising Caltech, USA; IPAC, USA; WIS, Israel; OKC, Sweden; JSI/UMd, USA; DESY, Germany; TANGO, Taiwan; UW Milwaukee, USA; LANL, USA; TCD, Ireland; IN2P3, France. GROWTH acknowledges generous support of the NSF under PIRE Grant No 1545949. Alert distribution service provided by DIRAC@UW (Patterson et al. 2019). Alert database searches are done by AMPEL (Nordin et al. 2019). Alert filtering is performed with the AMPEL Follow-up Pipeline (Stein et al. 2021).