Gamma-ray Burst 180722A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

• none

• GCN Notice
  

  TITLE:           GCN/MAXI NOTICE
  NOTICE_DATE:     Sun 22 Jul 18 06:41:49 UT
  NOTICE_TYPE:     MAXI Unknown Source Position
  EVENT_ID_NUM:    321176797
  EVENT_RA:        302.61d {+20h 10m 27s} (J2000),
                   302.81d {+20h 11m 15s} (current),
                   302.08d {+20h 08m 19s} (1950)
  EVENT_DEC:       +24.24d {+24d 14' 13"} (J2000),
                   +24.29d {+24d 17' 34"} (current),
                   +24.09d {+24d 05' 17"} (1950)
  EVENT_ERROR:     1.0 [deg radius, stat+sys, 90% containment]
  EVENT_FLUX:      536.0 +- 0.0 [mCrab]
  EVENT_DATE:      18321 TJD;   203 DOY;   18/07/22
  EVENT_TIME:      21556.00 SOD {05:59:16.00} UT
  EVENT_TSCALE:    1s
  EVENT_EBAND:     Low, 2-4 keV
  SUN_POSTN:       121.59d {+08h 06m 22s}  +20.27d {+20d 16' 00"}
  SUN_DIST:        135.42 [deg] 
  MOON_POSTN:      237.20d {+15h 48m 48s}  -14.95d {-14d 57' 15"}
  MOON_DIST:        75.08 [deg] 
  MOON_ILLUM:      74 [%] 
  GAL_COORDS:       63.45, -5.00 [deg] galactic lon,lat of the burst (or transient)       
  ECL_COORDS:      312.23, 43.01 [deg] ecliptic lon,lat of the burst (or transient)      
  COMMENTS:        MAXI Unknown Source Position. GRB or unknown X-ray Transient.
  

• GCN Circular #23005
  R. Shimomukai (JAXA), H. Negoro (Nihon U.), W. Iwakiri (Chuo U.), M. Nakajima, W. Maruyama, A. Sakamaki (Nihon U.), T. Mihara, S. Nakahira, F. Yatabe, Y. Takao, M. Matsuoka (RIKEN), N. Kawai, M. Sugizaki, Y. Tachibana, K. Morita (Tokyo Tech), T. Sakamoto, M. Serino, S. Sugita, Y. Kawakubo, T. Hashimoto, A. Yoshida (AGU), S. Ueno, H. Tomida, M. Ishikawa, Y. Sugawara, N. Isobe (JAXA), Y. Ueda, A. Tanimoto, T. Morita, S. Yamada (Kyoto U.), Y. Tsuboi, R. Sasaki, H. Kawai, T. Sato (Chuo U.), H. Tsunemi, T. Yoneyama (Osaka U.), M. Yamauchi, K. Hidaka, S. Iwahori (Miyazaki U.), T. Kawamuro (NAOJ), K. Yamaoka (Nagoya U.), M. Shidatsu (Ehime U.) report on behalf of the MAXI team:
  The MAXI/GSC nova alert system triggered on a bright uncatalogued X-ray transient source at 05:59:06 UT on 2018 July 22. Assuming that the source flux was constant over the transit, we obtain the source position at (R.A., Dec) = (302.894 deg, 24.221 deg) = (20 11 34, +24 13 15) (J2000) with a statistical 90% C.L. elliptical error region with long and short radii of 0.21 deg and 0.17 deg, respectively. The roll angle of the long axis from the north direction is 14.0 deg counterclockwise. There is an additional systematic uncertainty of 0.1 deg (90% containment radius).
  We estimated a rectangular error box for the transient source with the following corners:

  (301.985, 24.469) deg = (20 07 56, +24 28 07) (J2000)
  (301.898, 24.157) deg = (20 07 35, +24 09 26) (J2000)
  (303.593, 23.939) deg = (20 14 22, +23 56 18) (J2000)
  (303.685, 24.249) deg = (20 14 44, +24 14 56) (J2000)
  

  The X-ray flux averaged over the scan was 259 +- 32 mCrab (4.0-10.0keV, 1 sigma error).
  There was no significant excess flux in the previous transit at UT 04:26.
• GCN Circular #23006
  V. Lipunov, E. Gorbovskoy, N.Tiurina, V.Kornilov, A.Kuznetsov, V.Chazov, I. Gorbunov, D.Zimnukhov, D.Kuvshinov, P.Balanutsa, V.Vladimirov, D.Vlasenko Lomonosov Moscow State University,SAI
  D. Buckley, South African Astronomical Observatory (SAAO)
  R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres The Instituto de Astrofisica de Canarias (IAC)
  A. Tlatov, V.Senik, D. Dormidontov Kislovodsk Solar Station of the Pulkovo Observatory
  R. Podesta, F. Podesta, C. Lopez, C.Francile Observatorio Astronomico Felix Aguilar (OAFA)
  H.Levato, Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)
  O. Gres, N.M.Budnev , Yu.Ishmuhametova Irkutsk State University (ISU)
  A. Gabovich, V. Yurkov, Yu. Sergienko Blagoveschensk Educational State University (BSPU)
  MASTER-OAFA robotic telescope (MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) was pointed to the GRB180722A( Shimomukai et al., MAXI/GSC detection, GCN #23005) 17 sec after notice time and 2572 sec after trigger time at 2018-07-22 06:42:08 UT. On our first (180s exposure) set we not found optical transient within MAXI error-box (ra=302.613 dec=24.2364 r=1) brighter then 17.7.
  The observations made on zenit distance = 62 degrees, galaxy latitude b = -5 degrees. The moon (74 % bright part) is 4 degrees above the horizon. The distance between moon and object is 75 . The sun altitude is -61.0 degree. The object can be observed till 2018-07-22 09:45:34.
  The message may be cited.
• GCN Circular #23015
  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 180722A. Automated analysis of the XRT data will be presented online at http://www.swift.ac.uk/xrt_products/TILED_GRB00071
  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.
• GCN Circular #23026
  V. Lipunov, E. Gorbovskoy, N.Tiurina, D.Vlasenko, V.Kornilov, A.Kuznetsov, V.Chazov, I. Gorbunov, D.Zimnukhov, D.Kuvshinov, P.Balanutsa, V.Vladimirov, Lomonosov Moscow State University,SAI
  D. Buckley, South African Astronomical Observatory (SAAO)
  R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres The Instituto de Astrofisica de Canarias (IAC)
  A. Tlatov, V.Senik, D. Dormidontov Kislovodsk Solar Station of the Pulkovo Observatory
  R. Podesta, F. Podesta, C. Lopez, C.Francile Observatorio Astronomico Felix Aguilar (OAFA)
  H.Levato, Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)
  O. Gres, N.M.Budnev , Yu.Ishmuhametova Irkutsk State University (ISU)
  A. Gabovich, V. Yurkov, Yu. Sergienko Blagoveschensk Educational State University (BSPU)
  MASTER-SAAO robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in SAAO was starting second survey on the MAXI GRB180722A error-box (ra=20 11 34 dec=+24 13 15 r=1) 61549 sec after notice time and 65839 sec after trigger time at 2018-07-23 00:16:35 UT (Shimomukai et al., MAXI/GSC detection, GCN #23005; Lipunov et al., GCN #23006). The 5-sigma upper limit on our first (180s exposure) set is about 19.0 mag
  This error-box was observed by MASTER-Amur ( 2018-07-23 12:53:17-14:00:20UT, 60s, mlim=17.8) and another MASTER sites.
  The coverage map of the 3 sigms error box is available at http://master.sai.msu.ru/static/OT/MASTERMAXIGRB180722A.jpg
  The observations made on zenit distance = 61 degrees, galaxy latitude b = -6 degree. The moon (80 % bright part) is 17 degrees above the horizon. The distance between moon and object is 69 The sun altitude is -65.7 degree. The object can be observed till 2018-07-23 03:41:44
  The message may be cited.
  
• GCN Circular #23032
  P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), B. Sbarufatti (INAF-OAB/PSU), D.N. Burrows (PSU), A. Tohuvavohu (PSU), S.L. Gibson (U. Leicester), Z. Liu (NAOC / U. Leicester), J.P. Osborne (U. Leicester), A. D'Ai (INAF-IASFPA) 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 180722A (Shimomukai et al. GCN Circ. 23005) in a series of observations tiled on the sky. The total exposure time is 1.2 ks, distributed over 7 tiles; the maximum exposure at a single sky location was 391 s. The data were collected between T0+45.7 ks and T0+47.1 ks, and are entirely in Photon Counting (PC) mode.
  No X-ray sources have been detected. The 3-sigma upper limit in the field (not including the regions where the tiles overlap) ranges from ~0.04 to ~0.12 ct s^-1, corresponding to a 0.3-10 keV observed flux of 1.8e-12 to 4.9e-12 erg cm^-2 s^-1 (assuming a typical GRB spectrum).
  The results of the XRT-team automatic analysis of the tiled XRT observations, including a position-specific upper limit calculator, are available at http://www.swift.ac.uk/xrt_products/TILED_GRB00071.
  This circular is an official product of the Swift-XRT team.