Gamma-ray Burst 190129A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

• none

• GCN Circular #23806
  S. Nakahira (RIKEN), S. Sugita (AGU), H. Negoro, M. Nakajima, A. Sakamaki, W. Maruyama, M. Aoki, K. Kobayashi (Nihon U.), T. Mihara, F. Yatabe, Y. Takao, M. Matsuoka (RIKEN), T. Sakamoto, M. Serino, Y. Kawakubo, T. Hashimoto, A. Yoshida (AGU), N. Kawai, M. Sugizaki, Y. Tachibana, K. Morita (Tokyo Tech), S. Ueno, H. Tomida, M. Ishikawa, Y. Sugawara, N. Isobe, R. Shimomukai, T. Midooka (JAXA), Y. Ueda, A. Tanimoto, T. Morita, S. Yamada, S. Ogawa (Kyoto U.), Y. Tsuboi, W. Iwakiri, R. Sasaki, H. Kawai, T. Sato (Chuo U.), H. Tsunemi, T. Yoneyama, K. Asakura, S. Ide (Osaka U.), M. Yamauchi, K. Hidaka, S. Iwahori (Miyazaki U.), T. Kawamuro (NAOJ), K. Yamaoka (Nagoya U.), M. Shidatsu (Ehime U.), Y. Kawakubo (LSU) report on behalf of the MAXI team:
  The MAXI/GSC nova alert system triggered a bright uncatalogued X-ray transient source at 12:21:40 UT on January 29, 2019. Assuming that the source flux was constant over the transit, we obtain the source position at (R.A., Dec) = (11.459 deg, -31.887 deg) = (00 45 50, -31 53 13) (J2000) with a statistical 90% C.L. elliptical error region with long and short radii of 0.16 deg and 0.15 deg, respectively. The roll angle of long axis from the north direction is 40.0 deg counterclockwise. There is an additional systematic uncertainty of 0.1 deg (90% containment radius).
  The X-ray flux averaged over the scan was 306 +- 37 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) = (10.934, -32.736) deg = (00 43 44, -32 44 09) (J2000)
  (R.A., Dec) = (11.230, -32.814) deg = (00 44 55, -32 48 50) (J2000)
  (R.A., Dec) = (11.935, -30.870) deg = (00 47 44, -30 52 12) (J2000)
  (R.A., Dec) = (11.645, -30.793) deg = (00 46 34, -30 47 34) (J2000)
  

  There was no significant excess flux in the previous transit at UT 10:49 with an upper limit of 20 mCrab.
• GCN Circular #23810
  E. Bissaldi (Politecnico & INFN Bari), B. Mailyan (UAH) and C. Meegan (UAH) report on behalf of the Fermi GBM Team:
  "At 12:21:41.87 UT on 29 January 2019, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 190129A (trigger 570457306 / 190129515), which was also detected by MAXI/GSC (Nakahira et al. 2019, GCN 23806). The GBM on-ground location is consistent with the MAXI/GSC position.
  The angle from the Fermi LAT boresight at the GBM trigger time is 118 degrees.
  The GBM light curve shows/consists of a single peak with a duration (T90) of about 8.7 s (50-300 keV). The time-averaged spectrum from T0-1 s to T0+4 s is adequately fit by a power law function with an exponential high-energy cutoff. The power law index is -1.37 +/- 0.23 and the cutoff energy, parameterized as Epeak, is 78 +/- 19 keV.
  The event fluence (10-1000 keV) in this time interval is (9 +/- 1)E-07 erg/cm^2. The 1-sec peak photon flux measured starting from T0-0.38 s in the 10-1000 keV band is 3.7 +/- 0.3 ph/s/cm^2.
  The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
• GCN Circular #23815
  H. Onozawa, A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU), Y. Kawakubo (LSU), A. Tezuka, S. Matsukawa, T. Ito, H. Morita, Y. Sone (AGU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN), I. Takahashi (IPMU), Y. Asaoka, S. Ozawa, S. Torii (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U), W. Ishizaki (ICRR), M. L. Cherry (LSU), S. Ricciarini (U of Florence), A. V. Penacchioni, P. S. Marrocchesi (U of Siena), and the CALET collaboration:
  The long GRB 190129A (MAXI/GSC detection: Nakahira et al., GCN Circ. 23806; Fermi GBM detection: Bissaldi, Mailyan & Meegan, GCN Circ. 23810) triggered the CALET Gamma-ray Burst Monitor (CGBM) at 12:55:43.519 UTC on 29 January 2019. The burst signal was seen by the HXM2 and SGM detectors.
  The burst light curve shows a weak pulse which starts at T-2.2 sec and ends at T+4.8 sec. The T90 and T50 durations measured by the SGM data are 6.0 +- 2.2 sec and 3.0 +- 2.2 sec (40-1000 keV), respectively.
  The ground processed light curve is available at
  http://cgbm.calet.jp/cgbm_trigger/ground/1232801614/
  The CALET data used in this analysis are provided by the Waseda CALET Operation Center located at the Waseda University.