//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 31533 SUBJECT: GRB 220130A: GECAM detection DATE: 22/01/31 08:33:43 GMT FROM: Zhao Yi at POLAR Y. Zhao, S. L. Xiong, J. C. Liu, Y. Q. Zhang, C. Y. Li, S. L. Xie, S. Xiao, C. Cai, P. Zhang, X. Y. Zhao, Y. Huang, X. Y. Song, C. Zheng, Y. Zhao, Z. W. Guo, W. C. Xue, C. W. Wang, Q. B. Yi, B. X. Zhang, W. X. Peng, R. Qiao, D. Y. Guo, X. B. Li, X. Ma, L. M. Song, P. Wang, J. Wang, Z. Zhang, S. J. Zheng, W. Chen, J. J. He, G. Y. Zhao, Y. Q. Du, H. Wu, J. Liang, Q. Luo, X. L. Zhang, H. M. Zhang, Z. H. An, M. Gao, K. Gong, B. Li, C. Li, J. H. Li, X. Q. Li, Y. G. Li, X. H. Liang, X. J. Liu, Y. Q. Liu, X. L. Sun, Y. L. Tuo, J. Z. Wang, X. Y. Wen, Y. B. Xu, Y. P. Xu, S. Yang, C. Y. Zhang, D. L. Zhang, Fan Zhang, Fei Zhang, X. Zhou, F. J. Lu, S. N. Zhang (IHEP) report on behalf of GECAM team: During the commissioning phase, GECAM-B was triggered in-flight by a long burst, GRB 220130A, at 2022-01-30T23:15:59.600 UTC (denoted as T0), which was also observed by INTEGRAL/SPI-ACS. GECAM alert data was downlinked to the ground through the short message service of BeiDou Navigation Satellite System (BDS) within ~60 s after T0. According to the BDS alert data, this burst mainly consists of multiple pulses with a duration of about 70 s. The GECAM light curve could be found here: http://twiki.ihep.ac.cn/pub/GECAM/GRBList/GRB220130A_lc.png Using the automatic on-ground localization pipeline with the BDS alert data, GECAM-B localized this burst to the following position (J2000): Ra: 356.8 deg Dec: -50.1 deg Err: 3.3 deg (1-sigma, statistical only) The current systematic error of location is estimated to be several degrees which could be minimized by the ongoing calibration. The GECAM preliminary location could be found here: http://twiki.ihep.ac.cn/pub/GECAM/GRBList/GRB220130A_loc.png Please note that all GECAM results here are preliminary. The final analysis will be published in journal papers or GECAM online catalog. Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor (GECAM) mission consists of two small satellites (GECAM-A and GECAM-B) in Low Earth Orbit (600 km, 29 deg), launched on Dec 10, 2020 (Beijing Time), which was funded by the Chinese Academy of Sciences (CAS). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 31538 SUBJECT: GRB 220130A: Fermi GBM Observation DATE: 22/02/01 00:01:22 GMT FROM: Stephen Lesage at Fermi-GBM Team S. Lesage (UAH) reports on behalf of the Fermi Gamma-ray Burst Monitor Team: "At 23:14:35 UT on 30 January 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 220130A (trigger 665277280/220130968) which was also detected by GECAM (Y. Zhao, et al. 2022, GCN 31533). The Fermi GBM on-ground location is consistent with the GECAM position. The angle from the Fermi LAT boresight is 69 degrees. The GBM light curve contains a small peak followed by a larger emission episode with a duration (T90) of about 61 s (10-1000 keV). The time-averaged spectrum from T0-2.0 to T0+163.8 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -0.85 +/- 0.02 and the cutoff energy, parameterized as Epeak, is 233 +/- 8 keV. A Band function fits the spectrum equally well with Epeak= 203 +/- 10 keV, alpha = -0.79 +/- 0.03 and beta = -2.4 +/- 0.1. The event fluence (10-1000 keV) in this time interval is (5.7 +/- 0.1)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+115.2 s in the 10-1000 keV band is 11.8 +/- 0.3 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog:https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html For Fermi GBM data and info, please visit the official Fermi GBM Support Page:https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/" //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 31548 SUBJECT: IPN triangulation of GRB 220130A DATE: 22/02/04 22:57:14 GMT FROM: Dmitry Svinkin at Ioffe Institute D. Svinkin, D. Frederiks, A. Ridnaia, A. Lysenko, and T. Cline on behalf of the Konus-Wind team, A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo, and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team, A. Goldstein, M. S. Briggs, and C. Wilson-Hodge on behalf of the Fermi GBM team, and S. Barthelmy, J. Cummings, H. Krimm, D. Palmer, and A. Tohuvavohu on behalf of the Swift-BAT team, report: The long-duration GRB 220130A (GECAM detection: Zhao et al., GCN Circ. 31533; Fermi-GBM detection: Lesage et al., GCN Circ. 31538) was detected by Fermi (GBM trigger 665277280), GECAM-B (GRD), Konus-Wind, and INTEGRAL (SPI-ACS) at about 83676 s UT (23:14:36). We have triangulated it to a preliminary, 3 sigma error box whose coordinates are: ----------------------- RA(2000) Dec(2000) deg deg ----------------------- Corners: 5.551 -47.554 358.843 -46.178 343.052 -61.567 348.140 -66.257 ------------------------ The error box area is 94.5 deg2, and its maximum dimension is 19 deg (the minimum one is 4.9 deg). The Sun distance was about 58 deg. This box may be improved. The IPN localization is consistent with, but reduces the area of, the Fermi (GBM) and GECAM localizations. A triangulation map and HEALPix FITS file are posted at http://www.ioffe.ru/LEA/GRBs/GRB220130_T83760/IPN/ The Konus-Wind time history and spectrum will be given in a forthcoming GCN Circular. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 31555 SUBJECT: Konus-Wind detection of GRB 220130A DATE: 22/02/06 12:47:42 GMT FROM: Dmitry Frederiks at Ioffe Institute D. Frederiks, A.Lysenko, A. Ridnaia, D. Svinkin, A. Tsvetkova, M. Ulanov, and T. Cline, on behalf of the Konus-Wind team, report: The long GRB 220130A (GECAM detection: Zhao et al., GCN Circ. 31533; Fermi-GBM detection: Lesage et al., GCN Circ. 31538; IPN localization: Svinkin et al., GCN 31548) triggered Konus-Wind (KW) at T0=83760.565 s UT (23:16:00.565). The burst light curve shows a weak emission episode in the interval from ~T0-90 s to ~T0-50 s, followed by a bright, multi-peaked pulse, which starts at ~T0-40 s and has a total duration of ~130 s. The emission is seen up to ~10 MeV. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB220130_T83760/ As observed by Konus-Wind, the burst had a fluence of (7.6 ± 1.2)x10^-5 erg/cm^2 and a 64-ms peak energy flux, measured from T0 + 13.824 s, of (4.9 ± 1.2)x10^-6 erg/cm^2/s (both in the 20 keV - 10 MeV energy range). The time-integrated spectrum (measured from T0 to T0+98.560 s) is best fit in the 20 keV - 15 MeV range by the GRB (Band) function with the following model parameters: the low-energy photon index alpha = -0.74 (-0.13,+0.15), the high energy photon index beta = -2.50 (-0.53,+0.25), the peak energy Ep = 236 (-25,+28) keV, chi2 = 89/97 dof. The spectrum near the peak count rate (measured from T0+8.448 s to T0+16.640 s) is best fit in the 20 keV - 15 MeV range by the GRB (Band) function with the following model parameters: the low-energy photon index alpha = -0.78 (-0.14,+0.22), the high energy photon index beta = -2.59 (-0.70,+0.34), the peak energy Ep = 397 (-95,+86) keV, chi2 = 110/97 dof. All the quoted errors are estimated at the 90% confidence level. All the presented results are preliminary.