//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25037 SUBJECT: GRB 190708B: MAXI/GSC detection DATE: 19/07/08 21:35:14 GMT FROM: Motoko Serino at RIKEN/MAXI Y. Kawakubo (LSU), M. Nakajima (Nihon U.), M. Serino (AGU), H. Negoro, W. Maruyama, M. Aoki, K. Kobayashi (Nihon U.), S. Nakahira, T. Mihara, T. Tamagawa, M. Matsuoka (RIKEN), T. Sakamoto, S. Sugita, H. Nishida, A. Yoshida (AGU), Y. Tsuboi, W. Iwakiri, R. Sasaki, H. Kawai, T. Sato (Chuo U.), M. Shidatsu (Ehime U.), N. Kawai, M. Sugizaki, 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.) report on behalf of the MAXI team: The MAXI/GSC nova alert system triggered a bright uncatalogued X-ray transient source at 19:49:58 UT . Assuming that the source flux was constant over the transit, we obtain the source position at (R.A., Dec) = (326.571 deg, 7.711 deg) = (21 46 17, +07 42 39) (J2000) with a statistical 90% C.L. elliptical error region with long and short radii of 0.22 deg and 0.19 deg, respectively. The roll angle of long axis from the north direction is 125.0 deg counterclockwise. There is an additional systematic uncertainty of 0.1 deg (90% containment radius). The X-ray flux averaged over the scan was 394 +- 60 mCrab (4.0-10.0keV, 1 sigma error). Without assumptions on the source constancy,we obtain a rectangular error box for the transient source with the following corners: (R.A., Dec) = (325.953, 7.630) deg = (21 43 48, +07 37 47) (J2000) (R.A., Dec) = (326.121, 7.246) deg = (21 44 29, +07 14 45) (J2000) (R.A., Dec) = (327.396, 7.791) deg = (21 49 35, +07 47 27) (J2000) (R.A., Dec) = (327.229, 8.175) deg = (21 48 54, +08 10 30) (J2000) There was no significant excess flux in the previous transit at UT 19:29 and in the next transit at 21:02 UT with an upper limit of 20 mCrab for each. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25040 SUBJECT: GRB 190708B: Tiled Swift observations DATE: 19/07/09 12:21:11 GMT FROM: Phil Evans at U of Leicester P. A. Evans (U. Leicester) reports on behalf of the Swift team: Swift has initiated a series of observations, tiled on the sky, of the MAXI GRB 190708B. Automated analysis of the XRT data will be presented online at http://www.swift.ac.uk/xrt_products/TILED_GRB00080 Any uncatalogued X-ray sources detected in this analysis will be reported on this website and via GCN COUNTERPART notices. The probability of finding serendipitous sources, unrelated to the MAXI event is high: any X-ray source considered to be a probable afterglow candidate will be reported via a GCN Circular after manual consideration. Details of the XRT automated analysis methods are detailed in Evans et al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8). This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25041 SUBJECT: GRB 190708B: Tiled Swift observations DATE: 19/07/09 12:31:46 GMT FROM: Phil Evans at U of Leicester P. A. Evans (U. Leicester) reports on behalf of the Swift team: Swift has initiated a series of observations, tiled on the sky, of the MAXI GRB 190708B. Automated analysis of the XRT data will be presented online at http://www.swift.ac.uk/xrt_products/TILED_GRB00080 Any uncatalogued X-ray sources detected in this analysis will be reported on this website and via GCN COUNTERPART notices. The probability of finding serendipitous sources, unrelated to the MAXI event is high: any X-ray source considered to be a probable afterglow candidate will be reported via a GCN Circular after manual consideration. Details of the XRT automated analysis methods are detailed in Evans et al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8). This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25043 SUBJECT: Konus-Wind observation of GRB 190708B DATE: 19/07/09 15:08:44 GMT FROM: Anna Kozlova at Ioffe Institute A. Kozlova, S. Golenetskii, R.Aptekar, D. Frederiks, M. Ulanov, D. Svinkin, A. Tsvetkova, A.Lysenko, and T. Cline on behalf of the Konus-Wind team, report: A long GRB was detected by Konus-Wind (KW) in the waiting mode on July 8, 2019 at ~71160 s UT (19:46:00), ~240 s before the MAXI trigger (GRB 190708B; Kawakubo et al., GCN 25037). The burst light curve shows a single pulse with a duration of ~ 20 s. Taking into account the proximity of this burst to the MAXI/GSC trigger and the consistency of the KW ecliptic latitude response with the position of GRB 190708B we suggest that KW observed the main part of GRB 190708B. As observed by KW, the burst had a fluence of 3.44(-0.33,+1.35)x10^-6 erg/cm2 and a 2.944-s peak flux, measured from ~T0(MAXI)-236.3 s, of 2.54(-0.73,+1.21)x10^-7 erg/cm2/s (both in the 20 keV - 10 MeV energy range). Modeling the KW 3-channel time-integrated spectrum (from ~T0(MAXI)-242.2 s to ~T0(MAXI)-221.6 s) by a simple power-law model yields the power law index of -2.01(-0.08,+0.16), chi2 = 3.3/1 dof. Modeling this spectrum by a power law with exponential cutoff model dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) with the photon index alpha fixed to -1, yields Ep = 91.6 (-15.7,+28.7) keV, chi2 = 0.12/1 dof. The KW light curve of this burst is available at http://www.ioffe.rssi.ru/LEA/GRBs/GRB190708B All the quoted errors are estimated at the 1 sigma confidence level. All the presented results are preliminary. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25053 SUBJECT: GRB 190708B: Swift-XRT observations DATE: 19/07/11 06:46:42 GMT FROM: Boris Sbarufatti at PSU A. Tohuvavohu (PSU), J.A. Kennea (PSU), B. Sbarufatti (PSU), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), A. D'Ai (INAF-IASFPA), A. Melandri (INAF-OAB), P. D'Avanzo (INAF-OAB) and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team: Swift-XRT has performed follow-up observations of the MAXI-detected burst GRB 190708B (Kawakubo et al. GCN Circ. 25037) in a series of observations tiled on the sky. The total exposure time is 3.9 ks, distributed over 7 tiles; the maximum exposure at a single sky location was 1.2 ks. The data were collected between T0+58.5 ks and T0+69.2 ks, and are entirely in Photon Counting (PC) mode. One uncatalogued X-ray source has been detected, it is below the RASS limit and shows no definitive signs of fading. Therefore, at the present time we cannot confirm this as the afterglow. Details of this source are given below: Source 1: RA (J2000.0): 326.4868 = 21:45:56.83 Dec (J2000.0): +7.8821 = +07:52:55.5 Error: 7.7 arcsec (radius, 90% conf.) Count-rate: 0.0151 [+0.0054, -0.0044] ct s^-1 Distance: 685 arcsec from MAXI position. Flux: (2.13 [+0.77, -0.62])e-12 erg cm^-2 s^-1 (observed, 0.3-10 keV) A catalogued source was also detected. The results of the XRT-team automatic analysis of the tiled XRT observations, including a position-specific upper limit calculator, are available at https://www.swift.ac.uk/xrt_products/TILED_GRB00080. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 25073 SUBJECT: GRB 190708B: confirmation of the X-ray afterglow DATE: 19/07/15 19:19:43 GMT FROM: Boris Sbarufatti at PSU B. Sbarufatti (PSU) reports on behalf of the Swift/XRT team: Swift has performed further observations of the field of the MAXI/GSC-detected burst GRB 190708B (Kawabuko et al., GCN 25037). An additional 3.4 ks of data were collected between 5.96 days and 6.11 days after the MAXI trigger. Source 1, initially reported by Tohuvavohu et al. (GCN 25053) as the likely X-ray counterpart, has faded to a level of 2.9E-3 counts/s (1.3E-13 ergs/cm^2/s). Source 1 is therefore confirmed as the X-ray afterglow of GRB 190708B. This circular is an official product of the Swift-XRT team.