//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 28411 SUBJECT: IceCube-200911A: IceCube observation of a high-energy neutrino candidate event DATE: 20/09/11 17:39:03 GMT FROM: Cristina Lagunas Gualda at DESY The IceCube Collaboration (http://icecube.wisc.edu/) reports: On 20/09/11 at 14:19:46.23 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 0.968 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/134482_27754576.amon), more sophisticated reconstruction algorithms have been applied offline, with the direction refined to: Date: 20/09/11 Time: 14:19:46.23 UT RA: 51.11 (+ 4.42 - 11.01 deg 90% PSF containment) J2000 Dec: 38.11 (+ 2.35 - 1.99 deg 90% PSF containment) J2000 We note that this updated direction has shifted from the initial alert. The track from this neutrino event was just outside the instrumented volume, parallel to our detector string layout, which can introduce ambiguities in reconstructed directions. The shape of the error region for this event’s reconstructed direction (https://roc.icecube.wisc.edu/public/alerts/run00134482.evt000027754576/) reflects this ambiguity. We encourage follow-up by ground and space-based instruments to help identify a possible astrophysical source for the candidate neutrino. There is one Fermi 4FGL source located within the 90% localization region, 4FGL J0334.3+3920, located at RA: 53.58 deg, Dec: 39.34 deg (J2000), at a distance of 2.29 deg 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: 28412 SUBJECT: IceCube-200911A: not observable by Fermi-GBM DATE: 20/09/11 19:07:14 GMT FROM: Joshua Wood at MSFC/Fermi-GBM J. Wood (NASA/MSFC) reports on behalf of the Fermi-GBM team: At the time of the neutrino candidate IceCube-200911A (GCN 28411), Fermi was passing through the South Atlantic Anomaly from 21.4 minutes prior until 3.0 minutes after the trigger time; therefore the GBM detectors were disabled. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 28413 SUBJECT: IceCube-200911A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation DATE: 20/09/11 20:38:51 GMT FROM: Volodymyr Savchenko at ISDC,U of Geneve V. Savchenko, C. Ferrigno (ISDC/UniGE, Switzerland) J. Rodi (IAPS-Roma, Italy) A. Coleiro (APC, France) S. Mereghetti (INAF IASF-Milano, Italy) on behalf of the INTEGRAL multi-messenger collaboration: https://www.astro.unige.ch/cdci/integral-multimessenger-collaboration Using combination of INTEGRAL all-sky detectors (following [1]): SPI/ACS, IBIS/Veto, and IBIS we have performed a search for a prompt gamma-ray counterpart of unknown (GCN 28411). At the time of the event (2020-09-11 14:19:46 UTC, hereafter T0), INTEGRAL was operating in nominal mode. The peak of the event localization probability was at an angle of 84 deg with respect to the spacecraft pointing axis. This orientation implies strongly suppressed (15% of optimal) response of ISGRI, strongly suppressed (37% of optimal) response of IBIS/Veto, and near-optimal (85% of optimal) response of SPI-ACS. The background within +/-300 seconds around the event was very stable (excess variance 1.1). We have performed a search for any impulsive events in INTEGRAL SPI- ACS (as described in [2]), IBIS, and IBIS/Veto data. We do not detect any significant counterparts and estimate a 3-sigma upper limit on the 75-2000 keV fluence of 1.9e-07 erg/cm^2 (within the 50% probability containment region of the source localization) for a burst lasting less than 1 s with a characteristic short GRB spectrum (an exponentially cut off power law with alpha=-0.5 and Ep=600 keV) occurring at any time in the interval within 300 s around T0. For a typical long GRB spectrum (Band function with alpha=-1, beta=-2.5, and Ep=300 keV), the derived peak flux upper limit is ~1.6e-07 (5.6e-08) erg/cm^2/s at 1 s (8 s) time scale in 75-2000 keV energy range. We report for completeness and in order of FAP, all excesses identified in the search region. We find: 1 tentatively associated excess: T-T0 | scale | S/N | flux ( x 1e-06 erg/cm2/s) | FAP 0.211 | 0.7 | 3.5 | 2.67 +/- 0.751 +/- 0.739 | 0.00784 4 likely background excesses: T-T0 | scale | S/N | flux ( x 1e-06 erg/cm2/s) | FAP 171 | 3.1 | 3.6 | 1.37 +/- 0.356 +/- 0.379 | 0.299 20.4 | 0.05 | 4 | 1.17 +/- 0.287 +/- 0.324 | 0.705 97.1 | 0.65 | 3.7 | 2.95 +/- 0.779 +/- 0.816 | 0.736 -104 | 0.5 | 3.7 | 3.34 +/- 0.89 +/- 0.924 | 0.968 Note that FAP estimates (especially at timescales above 2s) may be possibly further affected by enhanced non-stationary local background noise. This list excludes any excesses for which FAP is close to unity. All results quoted are preliminary. This circular is an official product of the INTEGRAL Multi-Messenger team. [1] Savchenko et al. 2017, A&A 603, A46 [2] Savchenko et al. 2012, A&A 541A, 122S -- //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 28414 SUBJECT: IceCube Alert 200911.60: Global MASTER-Net observations report DATE: 20/09/11 21:39:30 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin, V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva, 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, O.Ershova (Irkutsk State University, API), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), V. Yurkov, A. Gabovich, Yu. Sergienko (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 200911.60 (trigger No 27754576,02h 48m 40.80s , +38d 07m 58.8s, R=0.54) errorbox 24990 sec after notice time and 25033 sec after trigger time at 2020-09-11 21:17:00 UT, with upper limit up to 19.1 mag. The observations began at zenith distance = 43 deg. The sun altitude is -41.5 deg. The galactic latitude b = -19 deg., longitude l = 147 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1438587 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 25124 | 2020-09-11 21:17:00 | MASTER-Tavrida | (02h 48m 45.05s , +38d 09m 31.6s) | C | 180 | 19.1 | 25533 | 2020-09-11 21:23:49 | MASTER-Tavrida | (02h 48m 41.01s , +38d 11m 42.3s) | C | 180 | 19.1 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 28415 SUBJECT: IceCube-200911A: No neutrino counterpart candidates in ANTARES search DATE: 20/09/12 17:06:13 GMT FROM: Antoine Kouchner at ANTARES Collaboration Alexis Coleiro (APC/Universite de Paris) and Damien Dornic (CPPM/CNRS) on behalf of the ANTARES Collaboration. Using data from the ANTARES detector, we have performed a follow-up analysis of the recently reported single track-like event IceCube-200911A (GCN 28411 >). The reconstructed origin was 7.3 degrees below the horizon for ANTARES. No up-going muon neutrino candidate events were recorded within the 90% error box of the IceCube event during a +/- 1h time-window centered on the IceCube event time, and over which the potential source remained visible all time. This leads to a preliminary 90% confidence level upper limit on the muon-neutrino fluence from a point source of 14 GeV.cm^-2 over the energy range 10 TeV - 8 PeV (the range corresponding to 5-95% of the detectable flux) for an E^-2 power-law spectrum, and 34 GeV.cm^-2 (1.5 TeV - 740 TeV) for an E^-2.5 spectrum. A search over an extended time window of +/- 1 day has also yielded no detection (23.5% visibility). ANTARES > is the largest undersea neutrino detector (Mediterranean Sea) and it is primarily sensitive to astrophysical neutrinos in the TeV-PeV energy range. At 10 TeV, the median angular resolution for muon neutrinos is about 0.5 degrees. In the range 1-100 TeV ANTARES has a competitive sensitivity to this position in the sky. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 28416 SUBJECT: IceCube-200911A: Upper limits from a search for additional neutrino events in IceCube DATE: 20/09/13 22:19:05 GMT FROM: Alex Pizzuto at ICECUBE/U of Wisconsin The IceCube Collaboration (http://icecube.wisc.edu/) reports: IceCube has performed a search for additional track-like muon neutrino events arriving from the direction of IceCube-200911A (https://gcn.gsfc.nasa.gov/gcn3/28411.gcn3) in a time range of 2 days centered on the alert event time (2020-09-10 14:19:46.23 UTC to 2020-09-12 14:19:46.23 UTC) during which IceCube was collecting good quality data. Excluding the event that prompted the alert, two additional track-like events are found in spatial coincidence with the 90% containment region of IceCube-200911A. We find that these data are consistent with atmospheric background expectations, with a p-value of 1.0. We accordingly derive a time-integrated muon-neutrino flux upper limit at the alert position of E^2 dN/ dE = 5.2 x 10^-5 TeV cm^-2 at 90% CL, under the assumption of an E^-2 power law. 90% of events IceCube would detect from a source at this declination with an E^-2 spectrum are approximately between 700 GeV and 400 TeV. A subsequent search was performed to include the month of data prior to the alert event (2020-08-12 14:19:46.23 UTC to 2020-09-12 14:19:46.23 UTC). In this case, we report a p-value of 1.0, consistent with no significant excess of track-like events, and a corresponding time-integrated muon-neutrino flux upper limit assuming an E^-2 spectrum (E^2 dN/dE) of 6.4 x 10^-5 TeV cm^-2 at the 90% CL. 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: 28421 SUBJECT: Fermi-LAT Gamma-ray Observations of IceCube-200911A and detection of a new gamma-ray source, Fermi J0330.1+3743 DATE: 20/09/14 14:54:51 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 neutrino event IC200911A (GCN 28411) 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 2020-09-11 at 14:19:46.23 UT (T0) with J2000 position RA =51.11 (+4.42 -11.01) deg, Decl. =38.11 (+2.35 -1.99) deg. The refined contour of the 90% PSF containment region is reported in GCN 28411. One cataloged >100 MeV gamma-ray source is located within the 90% IC200911A localization region. This is 4FGL J0334.3+3920 (The Fermi-LAT collaboration 2020, ApJS, 247, 33), associated with the radio galaxy 4C +39.12 at known redshift z = 0.02. Based on a preliminary analysis of the LAT data over the timescales of 1-day and 1-month prior to T0, this object is 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 IC200911A 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 < 5.4e-10 ph cm^-2 s^-1 for ~12-years (2008-08-04 / 2020-09-11 UTC), < 5.6e-9 (< 5.6e-8) ph cm^-2 s^-1 for a 1-month (1-day) integration time before T0. Within the 90% confidence localization of the neutrino, ~1.2 deg offset from the best-fit IC200911A position, a >5 sigma excess of gamma rays, Fermi J0330.1+3743 was detected in an analysis of the integrated LAT data (> 100 MeV) between 2008-08-04 and 2020-09-11. Assuming a power-law spectrum, the best-fit localization is (J2000) RA: 52.51, Dec: 37.73 (0.12 deg 99% containment, 0.06 deg 68% containment), with best-fit spectral parameters flux = (3 +/- 1)e-9 ph cm^-2 s^-1 and index = 2.2 +/- 0.1. In a preliminary analysis of the LAT data over one day and one month prior T0, Fermi J0330.1+3743 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: 28422 SUBJECT: IceCube-200911A: No significant detection in HAWC DATE: 20/09/14 19:46:15 GMT FROM: Hugo Ayala at Pennsylvania State University Hugo Ayala (PSU) reports on behalf of the HAWC collaboration (http://www.hawc-observatory.org/collaboration): On 2020/09/11 14:19:46 UTC, the IceCube collaboration reported a track-like very-high-energy event that has a high probability of being an astrophysical neutrino, IceCube-200911A. Location is at RA: 51.11 (+4.42/-11.01 deg 90% PSF containment) J2000 Dec: 38.11 (+2.35/-1.99 deg 90% PSF containment) J2000 (GCN circular 28411). We performed two types of analyses for the follow-up. The first is for a steady source in archival data and the second is a search for a transient source. We assume a power-law spectrum with an index of -2.3 for both analyses. The positions found in the analysis are not coincident with the new source detection from Fermi-LAT (see GCN 28421). Search for a steady source in archival data: The archival data spans from November 2014 to May 2018. We searched inside the reported IceCube error region. The most significant location, with p-value 4.61e-5 (1.56e-2 post-trials), is at RA 48.56 deg, Dec +36.98 deg (±0.13 deg 68% containment) J2000. We set a time-integrated 95% CL upper limit on gamma rays at the maximum position of: E^2 dN/dE = 3.86e-13 (E/TeV)^-0.3 TeV.cm^-2.s^-1 Search for a transient source. Since the event was not in our field of view at the time reported, we report the combined result for the transits before and after the IceCube event. Data acquisition started on 2020/09/09 13:29:22 UTC and ended 2020/09/11 13:48:10 UTC. The most significant location, with p-value 4.15e-03 (7.57e-1 post-trials), is at RA 50.32 deg, Dec +39.84 deg (±0.19 deg 68% containment) J2000. We set a time-integrated 95% CL upper limit at the position of maximum significance of: E^2 dN/dE = 1.18e-11 (E/TeV)^-0.3 TeV.cm^-2.s^-1 HAWC is a very-high-energy gamma-ray observatory operating in Central Mexico at latitude 19 deg. north. Operating day and night with over 95% duty cycle, HAWC has an instantaneous field of view of 2 sr and surveys 2/3 of the sky every day. It is sensitive to gamma rays from 300 GeV to 100 TeV. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 28434 SUBJECT: Swift-XRT observations of IceCube 200911A DATE: 20/09/17 03:21:29 GMT FROM: Timothee Gregoire at Penn State T. Gregoire (PSU), P.A. Evans (U. Leicester), J.A. Kennea (PSU), H. A. Ayala Solares (PSU), D.F. Cowen (PSU), J. DeLaunay (PSU) , D. B. Fox (PSU), A. Keivani (Columbia U.), J.P. Osborne (U. Leicester) report: Swift observed the field of IceCube 200911A (GCN Circ. 28411) between 16:38:01 2020 September 9 and 19:38:41 on 2020 September 9, collecting a total of 3.7 ks of cleaned photon counting (PC) mode data. The observations used a 4-point tiling pattern with a radius of ~0.3 degrees. We found no X-ray sources beyond artifacts caused by bright Earth limb contamination. The 3-sigma upper limit in the field was in the range 5-8 x10^-3 ct/sec.