//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 33244 SUBJECT: IceCube-230201A - IceCube observation of a high-energy neutrino candidate track-like event DATE: 23/02/01 12:49:02 GMT FROM: Dr. Massimiliano Lincetto at Ruhr-Universitaet Bochum The IceCube Collaboration (http://icecube.wisc.edu/) reports: On 2023-02-01 at 06:20:54.42 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 2.07 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/137603_30799022.amon) more sophisticated reconstruction algorithms have been applied offline, with the direction refined to: Date: 2023-02-01 Time: 06:20:54.42 UT RA: 345.41 (+2.50/-3.07 deg 90% PSF containment) J2000 Dec: +12.10 (+1.62/-1.53 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. Three gamma-ray sources listed in the 4FGL Fermi-LAT catalog are located within the 90% containment region. The sources are 4FGL J2256.7+1307, 4FGL J2308.9+1111 and 4FGL J2252.6+1245, located 1.6, 2.0 and 2.3 deg away from the best-fit position, respectively. 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: 33248 SUBJECT: Fermi-LAT gamma-ray observations of IceCube-230201A DATE: 23/02/01 20:41:13 GMT FROM: Sara Buson at GSFC/Fermi J. Sinapius (DESY-Zeuthen), S. Garrappa (Ruhr-Universitaet Bochum) and S. Buson (Univ. of Wuerzburg) on behalf of the Fermi-LAT collaboration: We report an analysis of observations of the vicinity of the IC230201A high-energy neutrino event (GCN 33244) 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 2023-02-01 at 06:20:54.42 UT (T0) with J2000 position RA = 345.41 (+2.50, -3.07) deg, Decl. = +12.10 (+1.62, -1.53) deg (90% PSF containment). Three cataloged gamma-ray (>100 MeV; The Fermi-LAT collaboration 2022, ApJS, 260, 53) sources are located within the 90% IC230201A localization region. Based on a preliminary analysis of the LAT data over the timescales of 1-day and 1-month prior to T0, these objects are not significantly detected (> 5 sigma). 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 IC230201A best-fit position. Assuming a power-law spectrum (photon index = 2.0 fixed) for a point source at the IC230201A best-fit position, the >100 MeV flux upper limit (95% confidence) is < 2.8e-10 ph cm^-2 s^-1 for ~14-years (2008-08-04 to 2023-02-01 UTC), and < 3.6e-9 (<2.4e-7) 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 region will continue. For these observations the Fermi-LAT contact persons are S. Garrappa (simone.garrappa at ruhr-uni-bochum.de), J. Sinapius (jonas.sinapius 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: 33250 SUBJECT: IceCube Alert 230201.26: Global MASTER-Net observations report DATE: 23/02/02 09:52:10 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-Amur robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Blagoveshchensk State Pedagogical University) was pointed to the IceCube Alert 230201.26 (trigger No 30799022,23h 04m 33.84s , +12d 02m 16.8s, R=0.51) errorbox 1 days 11538 sec after notice time and 1 days 11596 sec after trigger time at 2023-02-02 09:34:11 UT, with upper limit up to 16.5 mag. Observations started at twilight. The observations began at zenith distance = 59 deg. The sun altitude is -11.3 deg. The galactic latitude b = -43 deg., longitude l = 87 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2195910 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 98027 | 2023-02-02 09:34:11 | MASTER-Amur | (23h 02m 52.50s , +12d 41m 20.4s) | C | 60 | 15.9 | 98106 | 2023-02-02 09:35:30 | MASTER-Amur | (23h 10m 59.55s , +12d 40m 26.0s) | C | 60 | 16.1 | 98489 | 2023-02-02 09:40:53 | MASTER-Amur | (23h 05m 17.68s , +12d 05m 57.5s) | C | 180 | 16.5 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 33256 SUBJECT: IceCube-230201A: Upper limits from a search for additional neutrino events in IceCube DATE: 23/02/03 15:56:45 GMT FROM: Abhishek Desai 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-230201A (https://gcn.gsfc.nasa.gov/gcn3/33244.gcn3) in a time range of 1000 seconds centered on the alert event time (2023-02-01 06:12:34.421 UTC to 2023-02-01 06:29:14.421 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-230201A. 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-230201A is 1.3e-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 1e+05 GeV. A subsequent search was performed including 2 days of data centered on the alert event time (2023-01-31 06:20:54.421 UTC to 2023-02-02 06:20:54.421 UTC). In this case, we report a p-value of 0.17, 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-230201A ranges from 1.5e-01 to 1.6e-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) //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 33270 SUBJECT: IceCube-230201A: BOOTES-4/MET Optical Upper Limits DATE: 23/02/05 07:57:38 GMT FROM: Dingrong Xiong at Yunnan Observatories of CAS, China D. R. Xiong, J. M. Bai, Y. F. Fan, K. Ye, C. J. Wang, Y. X. Xin, B. L. Lun, J. R. Mao, X. H. Zhao, L. Xu, X. G. Yu, K. X. Lu, X. Ding, D. Q. Wang (Yunnan Observatories), A. J. Castro-Tirado, E. Fernandez-Garcia, Y. D. Hu (IAA-CSIC) and C. J. Perez del Pulgar (UMA) on behalf of the BOOTES team report: On 2023-02-01 at 06:20:54.42 UT IceCube detected a track-like event with a moderate probability of being of astrophysical origin. Three gamma-ray sources (4FGL J2256.7+1307, 4FGL J2308.9+1111 and 4FGL J2252.6+1245) listed in the 4FGL Fermi-LAT catalog are located within the 90% containment region (GCN 33244, 33248). We observed the three gamma-ray sources and the best-fit position of IceCube-230201A with BOOTES-4/MET robotic telescope.The magnitude was calculated using bright stars in the same frame and the Pan-STARRS catalogue as reference. We did not detect any optical source within the best-fit position, and also the optical counterparts of the three gamma-ray sources The upper limits of magnitudes (without being corrected for Galactic extinction) are given as follows. Source | Tmid-T0 (day) | UT (start) | Upper Limit (error) | Exposure Time | Filter -------------------------------------------------------------------------------------------------------------- Best-fit position| 2.274 | 23-02-03 12:55:15.82 | 19.3 (0.07) | 6*300s (co-added) | Clear J2256.7+1307 | 1.236 | 23-02-02 12:00:06.45 | 17.67 (0.16) | 2*300s (co-added) | Clear J2308.9+1111| 1.273 | 23-02-02 12:53:51.65 | 19.748 (0.04) | 2*300s (co-added) | Clear J2252.6+1245 | 1.286 | 23-02-02 13:13:22.89 | 19.06 (0.06) | 2*300s (co-added) | Clear ------------------------------------------------------------------------------------------------------------- The Burst Optical Observer and Transient Exploring System (BOOTES) is a world-wide automatic telescope network which aims to repaid follow-up of transient and astrophysical sources in the sky for which the first station was installed in 1998 (Hu et al. 2021). The fourth station of the BOOTES Network, BOOTES-4/MET, is located at the Lijiang Observatory of the Yunnan Observatories of China (Xiong et al. 2020). We acknowledge the support of these staffs from the BOOTES telescope networks.