//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 32997 SUBJECT: GRB 221201A: Fermi GBM Final Real-time Localization DATE: 22/12/01 12:35:06 GMT FROM: Fermi GBM Team at MSFC/Fermi-GBM The Fermi GBM team reports the detection of a likely LONG GRB At 12:24:45 UT on 1 Dec 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 221201A (trigger 691590290.314944 / 221201517). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 263.4, Dec = -70.4 (J2000 degrees, equivalent to J2000 17h 33m, -70d 24'), with a statistical uncertainty of 1.5 degrees. The angle from the Fermi LAT boresight is 130.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn221201517/quicklook/glg_skymap_all_bn221201517.png The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn221201517/quicklook/glg_healpix_all_bn221201517.fit The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn221201517/quicklook/glg_lc_medres34_bn221201517.gif //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 32998 SUBJECT: GRB 221201A: Swift detection of a burst DATE: 22/12/01 12:47:26 GMT FROM: Phil Evans at U of Leicester E. Troja (NASA/GSFC/UMCP), M. G. Bernardini (INAF-OAB), R. Brivio (INAF-OAB), P. D'Avanzo (INAF-OAB), S. Dichiara (PSU), P. A. Evans (U Leicester), R. A. J. Eyles-Ferris (U Leicester), M. Ferro (INAF-OAB), J.D. Gropp (PSU), J. A. Kennea (PSU), F. E. Marshall (NASA/GSFC), A. Melandri (INAF-OAB), K. L. Page (U Leicester), D. M. Palmer (LANL), C. Salvaggio (INAF-OAB), T. Sbarrato (INAF-OAB) and B. Sbarufatti (INAF-OAB) report on behalf of the Neil Gehrels Swift Observatory Team: At 12:25:05 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 221201A (trigger=1142847). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 266.933, -68.260 which is RA(J2000) = 17h 47m 44s Dec(J2000) = -68d 15' 33" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single peak structure with a duration of about 40 sec. The peak count rate was ~5000 counts/sec (15-350 keV), at ~-13 sec after the trigger. (The peak occurred during a pre-planned slew and the nominal trigger time is the start of the first post-slew image.) The XRT began observing the field at 12:27:56.2 UT, 170.6 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 266.9228, -68.2510 which is equivalent to: RA(J2000) = 17h 47m 41.47s Dec(J2000) = -68d 15' 03.6" with an uncertainty of 5.7 arcseconds (radius, 90% containment). This location is 35 arcseconds from the BAT onboard position, within the BAT error circle. No event data are yet available to determine the column density using X-ray spectroscopy. The initial flux in the 0.1 s image was 2.34e-08 erg cm^-2 s^-1 (0.2-10 keV). UVOT took a finding chart exposure of 202 seconds with the U filter starting 337 seconds after the BAT trigger. No credible afterglow candidate has been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of the XRT error circle. The typical 3-sigma upper limit has been about 19.2 mag. Data from the list of sources generated on-board are not available at this time. No correction has been made for the expected extinction corresponding to E(B-V) of 0.065. Burst Advocate for this burst is E. Troja (nora.gsfc AT gmail.com). Please contact the BA by email if you require additional information regarding Swift followup of this burst. In extremely urgent cases, after trying the Burst Advocate, you can contact the Swift PI by phone (see Swift TOO web site for information: http://www.swift.psu.edu/) //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 33000 SUBJECT: Swift GRB 221201A: Global MASTER-Net observations report DATE: 22/12/01 18:36:55 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, G.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin (Lomonosov Moscow State University, SAI, Physics Department), R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA), R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias), D. Buckley (South African Astronomical Observatory), O.A. Gres, N.M. Budnev (Irkutsk State University, API), L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), A. Gabovich, V.Yurkov (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) was pointed to the Swift GRB 221201A ( E. Troja et al., GCN 32998) errorbox 21718 sec after notice time and 21801 sec after trigger time at 2022-12-01 18:28:26 UT, with upper limit up to 16.2 mag. Observations started at twilight. The observations began at zenith distance = 64 deg. The sun altitude is -11.5 deg. The galactic latitude b = -20 deg., longitude l = 325 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2172144 We obtain a following upper limits. Tmid-T0 | Site |Filt.| Expt. | Limit| Comment _________|_____________________|_____|_______|______|________ 21891 | MASTER-SAAO | C | 180 | 16.2 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 33001 SUBJECT: GRB 221201A: Enhanced Swift-XRT position DATE: 22/12/01 19:58:22 GMT FROM: Phil Evans at U of Leicester J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) report on behalf of the Swift-XRT team. Using 1465 s of XRT Photon Counting mode data and 2 UVOT images for GRB 221201A, we find an astrometrically corrected X-ray position (using the XRT-UVOT alignment and matching UVOT field sources to the USNO-B1 catalogue): RA, Dec = 266.92463, -68.24884 which is equivalent to: RA (J2000): 17h 47m 41.91s Dec (J2000): -68d 14' 55.8" with an uncertainty of 2.1 arcsec (radius, 90% confidence). This position may be improved as more data are received. The latest position can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, MNRAS, 397, 1177). This circular was automatically generated, and is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 33002 SUBJECT: GRB 221201A: Swift-XRT refined Analysis DATE: 22/12/01 22:31:42 GMT FROM: Phil Evans at U of Leicester J.A. Kennea (PSU), A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), J.P. Osborne (U. Leicester), A. Melandri (INAF-OAB), T. Sbarrato (INAF-OAB), P. D'Avanzo (INAF-OAB), A. Tohuvavohu (U. Toronto), D.N. Burrows (PSU) and E. Troja report on behalf of the Swift-XRT team: We have analysed 6.4 ks of XRT data for GRB 221201A (Troja et al. GCN Circ. 32998), from 159 s to 30.1 ks after the BAT trigger. The data comprise 375 s in Windowed Timing (WT) mode (the first 10 s were taken while Swift was slewing) with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Osborne et al. (GCN Circ. 33001). The light curve can be modelled with a series of power-law decays. The initial decay index is alpha=5.33 (+0.28, -0.27). At T+214 s the decay steepens to an alpha of 6.37 (+0.24, -0.17) before breaking again at T+368 s to a final decay with index alpha=0.907 (+/-0.026). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 3.18 (+/-0.06). The best-fitting absorption column is 3.41 (+0.17, -0.16) x 10^21 cm^-2, in excess of the Galactic value of 7.5 x 10^20 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 1.93 (+0.13, -0.12) and a best-fitting absorption column of 2.7 (+/-0.5) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.8 x 10^-11 (5.3 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 2.7 (+/-0.5) x 10^21 cm^-2 Galactic foreground: 7.5 x 10^20 cm^-2 Excess significance: 6.5 sigma Photon index: 1.93 (+0.13, -0.12) If the light curve continues to decay with a power-law decay index of 0.907, the count rate at T+24 hours will be 0.049 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.9 x 10^-12 (2.6 x 10^-12) erg cm^-2 s^-1. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/01142847. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 33003 SUBJECT: GCN: GRB 221201A: Swift/UVOT Upper Limits DATE: 22/12/02 13:27:29 GMT FROM: Samantha Oates at MSSL S. R. Oates (U.Birmingham) and E. Troja (NASA/GSFC/UMCP) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 221201A 179 s after the BAT trigger (Troja et al., GCN Circ. 32998). No optical afterglow consistent with the XRT position (Osborne et al. GCN Circ. 33001) is detected in the initial UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC) exposure and subsequent exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white_FC 179 329 147 >20.1 white 179 1970 225 >20.2 v 1479 2020 78 >17.8 b 1404 2107 85 >18.8 u 337 2094 277 >19.2 w1 1529 2069 78 >18.4 m2 1504 2045 78 >18.5 w2 1454 1996 78 >18.6 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.066 in the direction of the burst (Schlegel et al. 1998). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 33011 SUBJECT: GRB 221201A: Fermi GBM observation DATE: 22/12/03 08:49:40 GMT FROM: Christian Malacaria at ISSI GRB 221201A: Fermi GBM observation C. Malacaria (ISSI) and C. Meegan (UAH) report on behalf of the Fermi GBM Team: "At 12:24:45.31 UT on 01 December 2022, the Fermi Gamma-Ray Burst Monitor (GBM) triggered and located GRB 221201A (trigger 691590290 / 221201517). This event was also observed by Swift/BAT and  Swift/XRT (GCN 32998). The GBM position is reported in the Fermi-GBM Final on-ground Localization (GCN 32997) and is consistent with the Swift position. The angle from the Fermi LAT boresight is 125 degrees. The GBM light curve shows a single pulse with a duration (T90) of about 29 s (50-300 keV). The time-averaged spectrum from T0-0 s to T0+15 s is best fit by a Band function with Epeak = 144 +/- 7 keV, alpha = -0.57 +/- 0.07, and beta = -2.5 +/- 0.1 The event fluence (10-1000 keV) in this time interval is (1.59 +/- 0.03)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+6.8 s in the 10-1000 keV band is 20.5 +/- 0.6 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: 33013 SUBJECT: GRB 221201A: Swift-BAT refined analysis DATE: 22/12/03 15:01:15 GMT FROM: Tyler Parsotan at UMBC/GSFC/CRESST II M. Stamatikos (OSU), S. D. Barthelmy (GSFC), H. A. Krimm (NSF),, S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa),, C. B. Markwardt (GSFC), D. M. Palmer (LANL),, T. Parsotan (GSFC/UMBC), T. Sakamoto (AGU), (i.e. the Swift-BAT team): Using the data set from T-239 to T+941 sec from the recent telemetry downlink, we report further analysis of BAT GRB 221201A (trigger #1142847) (Troja et al., GCN Circ. 32998). The BAT ground-calculated position is RA, Dec = 266.903, -68.230 deg which is RA(J2000) = 17h 47m 36.6s Dec(J2000) = -68d 13' 48.2" with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 51%. The mask-weighted light curve shows a single peaked pulse. T90 (15-350 keV) is 33.71 +- 2.03 sec (estimated error including systematics). The time-averaged spectrum from T-20.88 to T+22.92 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.63 +- 0.05. The fluence in the 15-150 keV band is 8.6 +- 0.2 x 10^-06 erg/cm2. The 1-sec peak photon flux measured from T-13.51 sec in the 15-150 keV band is 11.2 +- 0.6 ph/cm2/sec. All the quoted errors are at the 90% confidence level. The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/1142847/BA/