//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25011 SUBJECT: LIGO/Virgo S190707q: Upper limits from IceCube neutrino searches DATE: 19/07/07 10:27:01 GMT FROM: Alex Pizzuto at ICECUBE/U of Wisconsin IceCube Collaboration (http://icecube.wisc.edu/) reports: Searches [1,2] for track-like muon neutrino events detected by IceCube consistent with the sky localization of gravitational-wave candidate S190707q in a time range of 1000 seconds [3] centered on the alert event time (2019-07-07 09:25:06.181 UTC to 2019-07-07 09:41:46.181 UTC) have been performed. During this time period IceCube was collecting good quality data. No significant track-like events are found in spatial coincidence of S190707q calculated from the map circulated in the 1-Preliminary notice. IceCube's sensitivity assuming an E^-2 spectrum (E^2 dN/dE) to neutrino point sources within the locations spanned by the 90% spatial containment of S190707q ranges from 0.029 to 0.763 GeV cm^-2 in a 1000 second 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] Bartos et al. arXiv:1810.11467 (2018) and Countryman et al.arXiv:1901.05486 (2019) [2] Braun et al., Astroparticle Physics 29, 299 (2008) [3] Baret et al., Astroparticle Physics 35, 1 (2011) //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25012 SUBJECT: LIGO/Virgo S190707q: Identification of a GW compact binary merger candidate DATE: 19/07/07 10:41:43 GMT FROM: Sarah Antier at APC The LIGO Scientific Collaboration and the Virgo Collaboration report: We identified the compact binary merger candidate S190707q during real-time processing of data from LIGO Hanford Observatory (H1) and LIGO Livingston Observatory (L1) at 2019-07-07 09:33:26.181 UTC (GPS time: 1246527224.181). The candidate was found by the MBTAOnline [1], CWB [2], GstLAL [3], PyCBC Live [4], and SPIIR [5] analysis pipelines. S190707q is an event of interest because its false alarm rate, as estimated by the online analysis, is 5.3e-12 Hz, or about one in 1e4 years. The event's properties can be found at this URL: https://gracedb.ligo.org/superevents/S190707q The classification of the GW signal, in order of descending probability, is BBH (>99%), Terrestrial (<1%), BNS (<1%), NSBH (<1%), or MassGap (<1%). Assuming the candidate is astrophysical in origin, there is strong evidence against the lighter compact object having a mass < 3 solar masses (HasNS: <1%). Using the masses and spins inferred from the signal, there is strong evidence against matter outside the final compact object (HasRemnant: <1%). One sky map is available at this time and can be retrieved from the GraceDB event page:  * bayestar.fits.gz, an updated localization generated by BAYESTAR [6], distributed via GCN notice about 39 minutes after the candidate For the bayestar.fits.gz sky map, the 90% credible region is 1375 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 810 +/- 234 Mpc (a posteriori mean +/- standard deviation). For further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo Public Alerts User Guide .  [1] Adams et al. CQG 33, 175012 (2016)  [2] Klimenko et al. PRD 93, 042004 (2016)  [3] Messick et al. PRD 95, 042001 (2017)  [4] Nitz et al. PRD 98, 024050 (2018)  [5] Qi Chu, PhD Thesis, The University of Western Australia (2017)  [6] Singer & Price PRD 93, 024013 (2016) //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25013 SUBJECT: LIGO/Virgo S190707q : No neutrino counterpart candidates in ANTARES search DATE: 19/07/07 11:04:07 GMT FROM: Antoine Kouchner at ANTARES Collaboration M. Ageron (CPPM/CNRS), B. Baret (APC/CNRS), A. Coleiro (APC/Universite de Paris), M. Colomer (APC/Universite de Paris), D. Dornic (CPPM/CNRS), A. Kouchner (APC/Universite de Paris), T. Pradier (IPHC/Universite de Strasbourg) report on behalf of the ANTARES Collaboration: Using on-line data from the ANTARES detector, we have performed a follow-up analysis of the recently reported LIGO/Virgo S190707q event using the 90% contour of the bayestar probability map provided by the GW interferometers (GCN#25012 ). The ANTARES visibility at the time of the alert, together with the 50% and 90% contours of the probability map are shown at http://antares.in2p3.fr/GW/S190707q.png . Considering the location probability provided by the LIGO/Virgo collaborations, there is a 58.3% chance that the GW emitter was in the ANTARES **upgoing** field of view at the time of the alert. No up-going muon neutrino candidate events were recorded in the ANTARES sky during a +/-500s time-window centered on the time 2019-07-07 09:33:26 and in the 90% contour of the S190707q event. The expected number of atmospheric background events in the region visible by ANTARES is 5.14e-04 in the +/- 500s time window. An extended search during +/- 1 hour gives no up-going muon neutrino coincidence. The expected number of atmospheric background events in the region visible by ANTARES is 3.70e-03 in this larger time window. ANTARES is the largest undersea neutrino detector, installed in the Mediterranean Sea, and it is primarily sensitive to 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: 25014 SUBJECT: LIGO/Virgo S190707q: Coverage and upper limits from MAXI/GSC observations DATE: 19/07/07 11:25:02 GMT FROM: Motoko Serino at RIKEN/MAXI M. Serino, S. Sugita (AGU), N. Kawai, M. Sugizaki (Tokyo Tech), H. Negoro (Nihon U.), M. Nakajima, W. Maruyama, M. Aoki, K. Kobayashi (Nihon U.), S. Nakahira, T. Mihara, T. Tamagawa, M. Matsuoka (RIKEN), T. Sakamoto, H. Nishida, A. Yoshida (AGU), Y. Tsuboi, W. Iwakiri, R. Sasaki, H. Kawai, T. Sato (Chuo U.), M. Shidatsu (Ehime U.), M. Oeda, K. Shiraishi (Tokyo Tech), S. Ueno, H. Tomida, M. Ishikawa, Y. Sugawara, N. Isobe, R. Shimomukai, M. Tominaga (JAXA), Y. Ueda, A. Tanimoto, S. Yamada, S. Ogawa, K. Setoguchi, T. Yoshitake (Kyoto U.), H. Tsunemi, T. Yoneyama, K. Asakura, S. Ide (Osaka U.), M. Yamauchi, S. Iwahori, Y. Kurihara, K. Kurogi, K. Miike (Miyazaki U.), T. Kawamuro (NAOJ), K. Yamaoka (Nagoya U.), Y. Kawakubo (LSU) report on behalf of the MAXI team: We examined MAXI/GSC all-sky X-ray images (2-20 keV) after the LVC trigger S190707q at 2019-07-07 09:33:26.181 UTC (GCN 25012). At the trigger time of S190707q, the high-voltage of MAXI/GSC was on. The instantaneous field of view of GSC at the GW trigger time covered 2% of the 90% credible region of the bayestar sky map, in which we found no significant new X-ray source. The first one-orbit (92 min) scan observation with GSC after the event covered 93% of the 90% credible region of the bayestar skymap from 09:33:26 to 11:05:21 UTC (T0+0 to T0+5515 sec). No significant new source was found in the region in the one-orbit scan observation. A typical 1-sigma averaged upper limit obtained in one scan observation is 20 mCrab at 2-20 keV. If you require information about X-ray flux by MAXI/GSC at specific coordinates, please contact the submitter of this circular by email. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25017 SUBJECT: LIGO/Virgo S190707q: No counterpart candidates in HAWC observations DATE: 19/07/07 12:30:37 GMT FROM: Israel Martinez-Castellanos at UMD/HAWC The HAWC Collaboration (https://www.hawc-observatory.org) reports: The HAWC Collaboration performed a follow-up of the gravitational wave trigger S190707q (GCN #25012). At the time of the trigger the HAWC local zenith was oriented towards (RA, Dec) = (330.9 deg, 18.9deg). 31% of the GW candidate sky location probability fell within our observable field of view (0-45 deg zenith angle). We performed a search for a short timescale emission using 6 sliding time windows (dt = 0.3s, 1s, 3s, 10s, 30s and 100s), shifted forward in time by 20% of their width. We searched the 95% probability containment area in a timescale-dependent time period, from t0-5dt to t0+10dt, where t0 is the time of the GW trigger. No significant gamma-ray detection above the background was observed. The sensitivity of this analysis is greatly dependent on zenith angle, ranging from 18 deg to 45 deg for the area searched in this analysis. The 5sigma detection sensitivity to a 1s (100s) burst in the 80-800GeV energy range goes from 1.9e-06 erg/cm^2 to 1.1e-04 erg/cm^2 (1.1e-05 erg/cm^2 to 5.0e-04 erg/cm^2), depending on the zenith angle. HAWC is a TeV gamma ray water Cherenkov array located in the state of Puebla, Mexico. It is sensitive to the energy range ~0.1-100TeV, and monitors 2/3 of the sky every day with an instantaneous field-of-view of ~2 sr. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25018 SUBJECT: LIGO/Virgo S190707q: No counterpart candidates in AGILE-MCAL observations DATE: 19/07/07 14:28:18 GMT FROM: Fabrizio Lucarelli at SSDC/INAF-OAR F. Longo (Univ. Trieste, and INFN Trieste), C.Pittori, F. Lucarelli, F. Verrecchia (SSDC, and INAF/OAR), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), M. Cardillo, C. Casentini, G. Piano, A. Ursi (INAF/IAPS), A. Bulgarelli, V. Fioretti, N. Parmiggiani (INAF/OAS-Bologna), M. Pilia (INAF/OA-Cagliari) report on behalf of the AGILE Team: In response to the LIGO/Virgo GW event S190707q at T0 = 2019-07-07 09:33:26 (UT), a preliminary analysis of the AGILE minicalorimeter (MCAL) triggered data found no event candidates within a time interval covering -/+ 15 sec from the LIGO/Virgo T0. At the T0, about 80% of the S190707q 90% c.l. localization region was accessible to the AGILE-MCAL. Three-sigma upper limits (ULs) are obtained for a 1 s integration time at different celestial positions within the accessible S190707q localization region, from a minimum of 1.4E-06 erg cm^-2 to a maximum of 6.7E-06 erg cm^-2 (assuming as spectral model a single power law with photon index 1.5). The AGILE-MCAL detector is a CsI detector with a 4 pi FoV, sensitive in the energy range 0.4-100 MeV. Additional analysis of AGILE data is in progress. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25019 SUBJECT: LIGO/Virgo S190707q: Upper limits from AGILE-GRID observations DATE: 19/07/07 15:06:53 GMT FROM: Fabrizio Lucarelli at SSDC/INAF-OAR F. Longo (Univ. Trieste, and INFN Trieste), C.Pittori, F. Lucarelli, F. Verrecchia (SSDC, and INAF/OAR), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), M. Cardillo, C. Casentini, G. Piano, A. Ursi (INAF/IAPS), A. Bulgarelli, V. Fioretti, N. Parmiggiani (INAF/OAS-Bologna), M. Pilia (INAF/OA-Cagliari) report on behalf of the AGILE Team: In response to the LIGO-Virgo GW event S190707q at T0 = 2019-07-07 09:33:26.181 (UT) (GCN #25012), a preliminary analysis of the AGILE data at T0 shows that the Gamma-Ray Imaging Detector (GRID) exposure covered more than 25% of the 90% c.l. localization region (LR), observed at off-axis angles between 25 and 50 deg. We performed an analysis of the GRID data in the energy range 50 MeV - 10 GeV at T0, where good exposure of the S190707q 90% c.l. LR was available. No candidate gamma-ray transient was detected. The following preliminary GRID values of 3-sigma upper limit (UL) are obtained: (T0-2s; T0+2s): from 1.3e-06 to 5.3e-06 erg cm^-2 s^-1 with a 27% coverage of the 90% c.l. LR; (T0; T0+10s); from 6.9e-07 to 9.8e-06 erg cm^-2 s^-1 with a 26% coverage of the 90% c.l. LR; (T0; T0+100s); from 4.3e-07 to 8.9e-06 erg cm^-2 s^-1 with a 65% coverage of the 90% c.l. LR. These measurements were obtained with AGILE observing a large portion of the sky in spinning mode. Additional analysis of AGILE data is in progress. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25022 SUBJECT: LIGO/Virgo S190707q Global MASTER-Net observations report DATE: 19/07/07 17:05:22 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 (Lomonosov Moscow State University, SAI, Physics Department), R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA), H.Levato (Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE), 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-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the LIGO/Virgo S190707q errorbox 25837 sec after trigger time at 2019-07-07 16:44:03 UT, with upper limit up to 17.5 mag. Observations started at twilight. The observations began at zenit distance = 144 deg. The sun altitude is -11.8 deg. The galactic latitude b = -60 deg., longitude l = 98 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/ligo_1.php?id=10464 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 25927 | 2019-07-07 16:44:03 | MASTER-SAAO | ( 10h 12m 49.77s , -33d 50m 26.97s) | C | 180 | 17.5 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25026 SUBJECT: LIGO/Virgo S190707q: Upper limits from Fermi-GBM Observations DATE: 19/07/07 21:42:02 GMT FROM: Adam Goldstein at Fermi-GBM, USRA A. Goldstein (USRA) reports on behalf of the Fermi-GBM Team and the GBM-LIGO/Virgo group: For the LIGO/Virgo detection of GW trigger S190707q (GCN 25012) and using the initial BAYESTAR skymap, Fermi-GBM was observing 46.3% of the localization probability at event time. There was no Fermi-GBM onboard trigger around the event time of S190707q. An automated, blind search for short gamma-ray bursts below the onboard triggering threshold in Fermi-GBM also identified no counterpart candidates. The GBM targeted search, the most sensitive, coherent search for GRB-like signals, was run from +/- 30 s around merger time, and also identified no counterpart candidates. Part of the LVC localization region is behind the Earth for Fermi, located at RA = 171.8 and Dec = -21.4 with a radius of 67.4 degrees. We therefore set upper limits on impulsive gamma-ray emission. Using the representative soft, normal, and hard GRB-like templates described in arXiv:1612.02395, we set the following 3 sigma flux upper limits over 10-1000 keV, weighted by the GW localization probability, (in units of 10^-7 erg/s/cm^2): Timescale soft norm hard -------------------------------------- 0.128 s: 2.5 4.0 8.9 1.024 s: 0.8 1.2 2.2 8.192 s: 0.4 0.4 0.8 Assuming the median luminosity distance of 809.8 Mpc (z=0.167) from the GW detection, we estimate the following intrinsic luminosity upper limits over the 1 keV-10 MeV energy range (in units of 10^49 erg/s): Timescale soft norm hard -------------------------------------- 0.128 s: 3.0 4.4 16. 1.024 s: 1.0 1.3 4.0 8.192 s: 0.5 0.5 1.5 //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25029 SUBJECT: LIGO/Virgo S190707q: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observations DATE: 19/07/08 07:19:29 GMT FROM: Celia Sanchez-Fernandez at ISOC/ESA Celia Sanchez-Fernandez (ESA/ESAC, Spain), James Rodi (IAPS-Roma, Italy) V. Savchenko, C. Ferrigno (ISDC/UniGE, Switzerland) 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 S190707q (GCN 25012). At the time of the event (2019-07-07 09:33:26 UTC, hereafter T0), INTEGRAL was operating in nominal mode. The peak of the event localization probability was at an angle of 169 deg with respect to the spacecraft pointing axis. This orientation implies strongly suppressed (3.3% of optimal) response of ISGRI, near-optimal (88% of optimal) response of IBIS/Veto, and strongly suppressed (38% 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 2.6e-07 erg/cm^2 (within the 50% probability containement 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 ~2.1e-07 (6.4e-08) erg/cm^2/s at 1 s (8 s) time scale in 75-2000 keV energy range. For the mean reported distance 810.0 Mpc this corresponds to the limit on the total isotropic equivalent energy in 1 s of 2e+49 erg for the short GRB spectrum and for a long GRB spectrum isotropic equivalent luminosity in 1 s (8 s) of 1.7e+49 erg/s (5.1e+48 erg/s) 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 This message is intended only for the recipient(s) named above. It may contain proprietary information and/or protected content. Any unauthorised disclosure, use, retention or dissemination is prohibited. If you have received this e-mail in error, please notify the sender immediately. ESA applies appropriate organisational measures to protect personal data, in case of data privacy queries, please contact the ESA Data Protection Officer (dpo@esa.int). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25031 SUBJECT: LIGO/Virgo S190707q: No counterpart candidates in Fermi-LAT observations DATE: 19/07/08 09:46:50 GMT FROM: Elisabetta Bissaldi at INFN,Bari M. Axelsson (KTH and Stockholm Univ.), E. Bissaldi (Politecnico and INFN Bari) and F.Longo (University and INFN, Trieste) report on behalf of the Fermi-LAT Collaboration: "We have searched data collected by the Fermi Large Area Telescope (LAT) on July 7, 2019, for possible high-energy (E > 100 MeV) gamma-ray emission in spatial/temporal coincidence with the LIGO/Virgo trigger S190707q (GCN 25012). We define "instantaneous coverage" as the integral over the region of the LIGO probability map that is within the LAT field of view at a given a time, and "cumulative coverage" as the integral of the instantaneous coverage over time. Fermi-LAT had instantaneous coverage of ~35% of the LIGO probability region at the time of the trigger (T0 = 2019-07-07 09:33:26.181 UTC), and reached full coverage at T0+6.6 ks. We performed a search for a transient counterpart within the observed region of the 90% contour of the LIGO map in a fixed time window from T0 to T0+10 ks. No significant sources were found. We also performed a search which adapted the time interval of the analysis to the exposure of each region of the sky, and no additional excesses were found. Energy flux upper bounds for the fixed time interval between 100 MeV and 1 GeV for this search vary between 2.3e-10 and 6.8e-09 [erg/cm^2/s]. The Fermi-LAT point of contact for this event is Elisabetta Bissaldi (elisabetta.bissaldi@ba.infn.it)." 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: 25033 SUBJECT: LIGO/Virgo S190707q: Upper limits from CALET observations DATE: 19/07/08 17:54:52 GMT FROM: Yuta Kawakubo at Louisiana State U./CALET A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU), Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN), Y. Asaoka, S. Ozawa, S. Torii (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U), N. Cannady (GSFC/UMBC), M. L. Cherry (LSU), S. Ricciarini (U of Florence), P. S. Marrocchesi (U of Siena), and the CALET collaboration: The CALET Gamma-ray Burst Monitor (CGBM) was operating at the trigger time of S190707q T0 = 2019-07-07 09:33:26.181 UT (The LIGO Scientific Collaboration and Virgo Collaboration, GCN Circ. 25012). No CGBM on-board trigger occurred around the event time. Based on the LIGO-Virgo localization sky map, almost half of the high probability area was within the field-of-view of the CGBM SGM. The summed LIGO probabilities inside the CGBM HXM (7-3000 keV) and SGM (40 keV - 28 MeV) fields of view are 26% and 58%, respectively (and 76% credible region of the initial localization map was above the horizon). The HXM and SGM fields of view were centered at RA = 254.1 deg, Dec = 7.8 deg and RA = 262.4 deg, Dec = 2.2 deg at T0, respectively. Based on the analysis of the light curve data with 0.125 sec time resolution from T0-60 sec to T0+60 sec, we found no significant excess (signal-to-noise ratio >= 7) around the trigger time in either the HXM or the SGM data. The CALET Calorimeter (CAL) was operating in the low energy trigger mode at the trigger time of S190707q. Using the CAL data, we have searched for gamma-ray events in the 1-10 GeV band from -60 sec to +60 sec from the GW trigger time and found no candidates. The 90% upper limit of CAL is 2.1x10^-6 erg/cm^2/s (1-10 GeV) when the summed LIGO-Virgo probability reaches 20%. The CAL FOV was centered at RA= 262.4 deg, DEC= 2.2 deg at T0. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25044 SUBJECT: LIGO/Virgo S190707q: No counterpart candidates in the Swift/BAT Observations DATE: 19/07/09 23:43:01 GMT FROM: Takanori Sakamoto at AGU A. Y. Lien (GSFC/UMBC), S. D. Barthelmy (NASA/GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), A. A. Breeveld (MSSL-UCL), A. P. Beardmore (U. Leicester), D. N. Burrows (PSU), S. Campana (INAF-OAB), S. B. Cenko (NASA/GSFC), G. Cusumano (INAF-IASF PA), A. D'Ai (INAF-IASFPA), P. D'Avanzo (INAF-OAB), V. D'Elia (ASI-SSDC), S. Emery (UCL-MSSL), P. A. Evans (U. Leicester), P. Giommi (ASI), C. Gronwall (PSU), D. Hartmann (Clemson U.), J. A. Kennea (PSU), H. A. Krimm (NSF), N. P. M. Kuin (UCL-MSSL), F. E. Marshall (NASA/GSFC), A. Melandri (INAF-OAB), J. A. Nousek (PSU), S. R. Oates (Uni. of Warwick), P. T. O'Brien (U. Leicester), J. P. Osborne (U. Leicester), C. Pagani (U. Leicester), K. L. Page (U.Leicester), M. J. Page (UCL-MSSL), M. Perri (ASDC), J. L. Racusin (NASA/GSFC), B. Sbarufatti (INAF-OAB/PSU), M. H. Siegel (PSU), G. Tagliaferri (INAF-OAB), A. Tohuvavohu (PSU), E. Troja (NASA/GSFC/UMCP) report on behalf of the Swift team: We report the search results in the BAT data within T0 ± 100 s of the LVC event S190707q (LIGO/VIRGO Collaboration GCN Circ. 25012), where T0 is the LVC trigger time (2019-07-07T09:33:26.181 UTC). The center of the BAT FOV at T0 is RA = 143.593 deg, DEC = -17.350 deg, ROLL = 321.495 deg. The BAT Field of View (>10% partial coding) covers 36.58% of the integrated LVC localization probability, and 39.33% of the galaxy convolved probability (Evans et al. 2016). Within T0 ± 100 s, no significant detections (signal-to-noise ratio > ~ 5 sigma) are found in the BAT raw light curves with time bins of 64 ms, 1 s, and 1.6 s. Assuming an on-axis (100% coded) short GRB with a typical spectrum in the BAT energy range (i.e., a simple power-law model with a power-law index of -1.32, Lien & Sakamoto et al. 2016), the 5-sigma upper limit in the 1-s binned light curve corresponds to a flux upper limit (15-350 keV) of ~ 7.74 x 10^-8 erg/s/cm^2. BAT retains decreased, but significant, sensitivity to rate increases for gamma-ray events outside of its FOV. About 21.81% of the integrated LVC localization probability was outside of the BAT FOV but above the Earth's limb from Swift's location, and the corresponding flux upper limits for this region are within roughly an order of magnitude higher than those within the FOV. The results of the BAT analysis are available at https://swift.gsfc.nasa.gov/results/BATbursts/team_web/S190707q/web/source.html //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25045 SUBJECT: LIGO/Virgo S190707q: No counterpart candidates in the CNEOST DATE: 19/07/10 09:37:08 GMT FROM: Bin Li at PMO Bin Li, Hai-bin Zhao (PMO),Dong Xu, Zi-pei Zhu, Bang-Yao Yu,Tian-meng Zhang, Xu Zhou,Chen-zhou Cui, Hui-juan Wang(NAOC), Xue-feng Wu, Zhi-ping Jin, Tian-rui Sun, Hao Lu, Ge-tu Zhaori, Ren-quan Hong, Long-fei Hu (PMO), Xiao-feng Wang, Wen-xiong Li (THU),Li-fan Wang (PMO/TAMU), Jin-zhong Liu (XAO), Ji-rong Mao, Jin-ming Bai (YNAO), report on behalf of the CNEOST collaboration. We conducted optical imaging observations for gravitational wave alert with Chinese Near Earth Object Survey Telescope (CNEOST) at Xuyi astronomical station in Jiangsu Province, China (32.75N, 118.47E). The information of observations and preliminary results are listed below. Alert: LIGO/Virgo S190707q (GCN #25012) StartTime (UT): 2019-07-07T14:30:29.332 EndTime (UT): 2019-07-07T17:12:21.366 Skycover (Square Degree): 198.0 Telescope FoV (Square Degree):9.0 #id CentRA(D) CentDEC(D) LimiteMag3_sig 5_sig 10_sig Filter 1 295.518646 12.638072 20.538 19.628 17.472 SR 2 302.074249 15.441651 20.117 19.195 17.793 SR 3 303.018616 23.824675 20.428 19.496 18.045 SR 4 296.229309 15.440425 20.432 19.553 17.442 SR 5 295.523468 9.841532 20.139 19.214 17.761 SR 6 302.947357 21.046049 20.395 19.519 17.841 SR 7 297.722321 18.228382 20.333 19.427 17.487 SR 8 298.410583 12.654563 20.465 19.569 17.799 SR 9 306.944336 26.635813 20.103 19.180 17.930 SR 10 299.982086 21.071682 20.213 19.303 17.683 SR 11 292.704681 9.866313 20.165 19.260 17.595 SR 12 291.308624 1.434427 20.275 19.376 17.833 SR 13 298.410583 12.654563 20.465 19.569 17.799 SR 14 307.681488 35.065994 20.517 19.602 18.295 SR 15 295.518646 12.638072 20.538 19.628 17.472 SR 16 296.229309 15.440425 20.432 19.553 17.442 SR 17 307.756287 32.263035 20.466 19.553 18.180 SR 18 288.488525 -1.320782 20.225 19.351 17.655 SR 19 293.371429 7.044422 20.466 19.519 17.637 SR 20 299.165894 15.453922 20.553 19.607 17.758 SR 21 303.018616 23.824675 20.428 19.496 18.045 SR 22 326.081604 51.804840 20.383 19.456 17.805 SR Detailed data analysis is still in progress and any interesting transients will be reported later. The more resulte will available at http://www.cneost.org/opem/list.php?gdate=2019-07-07 //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25046 SUBJECT: LIGO/Virgo S190707q: MASTER OT seach result DATE: 19/07/10 11:48:25 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, N.Tyurina, E. Gorbovskoy, V.Kornilov, D.Vlasenko, P.Balanutsa,D.Vlasenko, V.Vladimirov, D.Zimnukhov, A.Kuznetsov, P.Balanutsa, I.Gorbunov, A. Chasovnikov, F.Balakin, V.Grinshpun, T.Pogrosheva (Lomonosov Moscow State University, SAI, Physics Department), R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres (The Instituto de Astrofisica de Canarias), D. Buckley (South African Astronomical Observatory), A. Tlatov, V.Senik, A.V. Parhomenko, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), R. Podesta, C. Lopez, C.Francile, F. Podesta (Observatorio Astronomico Felix Aguilar OAFA, San Juan National University), H.Levato (Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE,SJNU) O. Gress, N.M. Budnev, O.Ershova (Applied Physics Institute, Irkutsk Stat University), V. Yurkov, A. Gabovich, Yu. Sergienko, D. Kobcev (Blagoveschensk EducationState University), MASTER OT J195321.61+181050.3 discovery - preliminary dwarf nova outburst with ampl > 4m . MASTER-Kislovodsk auto-detection system discovered OT source at (RA, Dec) = 19h 53m 21.61s +18d 10m 50.3s on 2019-07-07.83846 UT during LVC S190707q inspect (GCN #25012, GCN #25022). The OT unfiltered magnitude is 16.6m (limit 17.9m). The OT is seen in 4 images. There is no minor planet at this place. We have reference image without OT on 2014-08-27.87829 UT with unfiltered magnitude limit 18.8m. Spectral observations are required. The discovery and reference images are available at: http://master.sai.msu.ru/static/OT/195321.61181050.3.png Folow up observations are required. Up to now we cover ~700 sq. degree inside the S190707q error box, which is makes up 62% from 50% errorbox and 45% of full error box. The cover map available here. https://master.sai.msu.ru/site/master2/ligo_1.php?id=10471 //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25048 SUBJECT: LIGO/Virgo S190707q: Updated sky localization DATE: 19/07/10 14:06:07 GMT FROM: Sarah Antier at APC The LIGO Scientific Collaboration and the Virgo Collaboration report: We have conducted further analysis of the LIGO and Virgo data around the time of the compact binary coalescence (CBC) candidate S190707q (GCN 25012). Parameter estimation has been performed using LALInference [1] and a new sky map, LALInference.offline.fits.gz, distributed via GCN Notice, is available for retrieval from the GraceDB event page: https://gracedb.ligo.org/superevents/S190707q LALInference.offline.fits.gz is the preferred sky map at this time. The 90% credible region is 921 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 781 ± 211 Mpc (a posteriori mean ± standard deviation). For further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo Public Alerts User Guide . [1] Veitch et al. PRD 91, 042003 (2015) //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25230 SUBJECT: LIGO/Virgo S190707q: AstroSat CZTI upper limits DATE: 19/07/31 06:51:48 GMT FROM: Varun Bhalerao at Indian Inst of Tech A. Anumarlapudi (IITB), Aarthy E. (PRL), V. Bhalerao (IITB), D. Bhattacharya (IUCAA), A. R. Rao (TIFR), S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration: We have carried a search for X-ray candidates in Astrosat CZTI data in a 100 sec window around the trigger time of the BBH merger event S190707q (UTC 2019-07-07 09:33:26.000, GraceDB event). CZTI is a coded aperture mask instrument that has considerable effective area for about 29% of the entire sky, but is also sensitive to brighter transients from the entire sky. At the time of merger, Astrosat's nominal pointing is (RA=23: 4:52.8 (346.220), DEC=-8:43:12.1 (-8.720)), which is 143.61 deg away from the maximum probability location. At the time of merger event, the Earth-satellite-transient angle corresponding to maximum probability location is ~ 52.68 deg and hence is occulted by Earth in satellite's frame. In a time interval of 100 sec around the event, 82.69 % of sky locations in the 90% probability region for the event is visible in the satellite's frame and the rest of 17.31 % is occulted by earth. CZTI data were de-trended to remove orbit-wise background variation. We then searched data from three of the four independent, identical quadrants to look for coincident spikes in the count rates. Searches were undertaken by binning the data in 0.1s, 1s, and 10s respectively. Statistical fluctuations in count rates were estimated by using data from 10 (+-5) neighbouring orbits. We selected confidence levels such that the probability of a false trigger in a 1000 sec window is 10^-4.We do not find any evidence for any hard X-ray transient in this window, in the CZTI energy range of 20-200 keV. We convert our count rates into flux by assuming that the source spectrum is a power law with alpha = -1.0. We use a detailed mass model of the satellite to calculate the instrument response for every htm grid point that fall in 90% LIGO localization region and calculate flux limit in that direction. We get the following upper limits for source flux in the 20-200 keV band by taking a probability weighted mean of flux limit and are reported here : 0.1 s: flux limit= 1.36e-06 ergs/cm^2/s 1.0 s: flux limit= 4.55e-06 ergs/cm^2/s 10.0 s: flux limit= 6.19e-06 ergs/cm^2/s CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project.