//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23482 SUBJECT: GRB 181202A: Swift detection of a burst with an optical counterpart DATE: 18/12/02 06:48:16 GMT FROM: David Palmer at LANL J. K. Cannizzo (NASA/UMBC), J.D. Gropp (PSU), K. L. Page (U Leicester), D. M. Palmer (LANL) and M. H. Siegel (PSU) report on behalf of the Neil Gehrels Swift Observatory Team: At 06:36:24 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 181202A (trigger=874334). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 280.745, +27.951 which is RA(J2000) = 18h 42m 59s Dec(J2000) = +27d 57' 03" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a multi-peaked structure with a duration of about 10 sec. The peak count rate was ~1100 counts/sec (15-350 keV), at ~1 sec after the trigger. The XRT began observing the field at 06:37:49.8 UT, 85.4 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source located at RA, Dec 280.73563, 27.95894 which is equivalent to: RA(J2000) = 18h 42m 56.55s Dec(J2000) = +27d 57' 32.2" with an uncertainty of 3.7 arcseconds (radius, 90% containment). This location is 41 arcseconds from the BAT onboard position, within the BAT error circle. This position may be improved as more data are received; the latest position is available at http://www.swift.ac.uk/sper. We cannot determine whether the source is fading at the present time. A power-law fit to a spectrum formed from promptly downlinked event data gives a column density consistent with the Galactic value of 1.67 x 10^21 cm^-2 (Willingale et al. 2013). UVOT took a finding chart exposure of 250 seconds with the U filter starting 86 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at RA(J2000) = 18:42:56.38 = 280.73490 DEC(J2000) = +27:57:35.0 = 27.95973 with a 90%-confidence error radius of about 0.63 arc sec. This position is 3.4 arc sec. from the center of the XRT error circle. The estimated magnitude is 17.67 with a 1-sigma error of about 0.15. No correction has been made for the expected extinction corresponding to E(B-V) of 0.14. Burst Advocate for this burst is J. K. Cannizzo (cannizzo AT milkyway.gsfc.nasa.gov). 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/too.html.) //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23483 SUBJECT: GRB 181202A: Enhanced Swift-XRT position DATE: 18/12/02 09:14:27 GMT FROM: Phil Evans at U of Leicester P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) report on behalf of the Swift-XRT team. Using 1454 s of XRT Photon Counting mode data and 1 UVOT images for GRB 181202A, 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 = 280.73491, +27.95964 which is equivalent to: RA (J2000): 18h 42m 56.38s Dec (J2000): +27d 57' 34.7" with an uncertainty of 1.8 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: 23487 SUBJECT: GRB 181202A: Swift-XRT refined Analysis DATE: 18/12/02 16:46:15 GMT FROM: Phil Evans at U of Leicester A.P. Beardmore (U. Leicester), A. D'Ai (INAF-IASFPA), A. Melandri (INAF-OAB), P. D'Avanzo (INAF-OAB), J.A. Kennea (PSU), B. Sbarufatti (INAF-OAB/PSU), D.N. Burrows (PSU), P.A. Evans (U. Leicester), J.P. Osborne (U. Leicester) and J.K. Cannizzo report on behalf of the Swift-XRT team: We have analysed 7.0 ks of XRT data for GRB 181202A (Cannizzo et al. GCN Circ. 23482), from 102 s to 29.4 ks after the BAT trigger. The data are entirely in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Evans et al. (GCN Circ. 23483). The light curve can be modelled with a power-law decay with a decay index of alpha=0.86 (+/-0.07). A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 1.69 (+0.22, -0.17). The best-fitting absorption column is 1.93 (+0.97, -0.26) x 10^21 cm^-2, consistent with the Galactic value of 1.7 x 10^21 cm^-2 (Willingale et al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 4.2 x 10^-11 (5.1 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 1.93 (+0.97, -0.26) x 10^21 cm^-2 Galactic foreground: 1.7 x 10^21 cm^-2 Excess significance: <1.6 sigma Photon index: 1.69 (+0.22, -0.17) If the light curve continues to decay with a power-law decay index of 0.86, the count rate at T+24 hours will be 3.4 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.4 x 10^-13 (1.8 x 10^-13) erg cm^-2 s^-1. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00874334. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23489 SUBJECT: GRB 181202A: Swift-BAT refined analysis DATE: 18/12/02 23:49:59 GMT FROM: Amy Lien at GSFC T. N. Ukwatta (LANL), S. D. Barthelmy (GSFC), J. K. Cannizzo (NASA/UMBC), J. R. Cummings (CPI), H. A. Krimm (NSF/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU) (i.e. the Swift-BAT team): Using the data set from T-240 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 181202A (trigger #874334) (Cannizzo et al., GCN Circ. 23482). The BAT ground-calculated position is RA, Dec = 280.737, 27.976 deg which is RA(J2000) = 18h 42m 56.9s Dec(J2000) = +27d 58' 33.4" with an uncertainty of 2.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 96%. The mask-weighted light curve shows a double-peaked structure that starts at ~T0 and ends at ~T+7 s. The two peaks occur at ~T+1 s and ~T+6 s, respectively. T90 (15-350 keV) is 6.56 +- 0.61 sec (estimated error including systematics). The time-averaged spectrum from T-0.26 to T+6.76 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.61 +- 0.24. The fluence in the 15-150 keV band is 2.5 +- 0.4 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+0.69 sec in the 15-150 keV band is 0.9 +- 0.2 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/874334/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23490 SUBJECT: GRB 181202A: Global MASTER-Net optical observations DATE: 18/12/03 01:24:30 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, V.Kornilov, D.Kuvshinov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.V.Chazov, D. Vlasenko Lomonosov Moscow State University, Sternberg Astronomical Institute, Moscow State University A. Tlatov, V.Senik, A.V. Parhomenko, D. Dormidontov Kislovodsk Solar Station of the Pulkovo Observatory K. Ivanov, O. Gres, N.M. Budnev, S. Yazev, O. Chuvalaev, V. Poleshchuk Irkutsk State University V. Yurkov, A. Gabovich, Yu. Sergienko Blagoveschensk Educational State University, Blagoveschensk R. Podesta, Carlos Lopez and F. Podesta Observatorio Astronomico Felix Aguilar (OAFA) Hugo Levato and Carlos Saffe Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE) R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres The Instituto de Astrofisica de Canarias D. Buckley, S. Potter, A. Kniazev, M. Kotze South African Astronomical Observatory MASTER-Tunka robotic telescope (MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Applied Physics Institute, Irkutsk State University) was pointed to the Swift GRB 181202A (Cannizzo et al., GCN #23482) 13216 sec after trigger time at 2018-12-02 10:17:08. On best sum (1800s total exposure) set we haven`t found optical transient within Swift error-box (ra=280.733 dec=27.9592 r=0.05). The 5-sigma upper limit has been about 19.0 mag ==================================================================== The galactic latitude b = 14 deg., longitude l = 58 deg. The observations made on zenit distance = 42 deg.The moon (25 % bright part) below the horizon (The altitude of the Moon is -26 deg. ). Observations started at twilight. The sun altitude is -10.6 deg. The object can be observed till sunrise at 2018-12-02 00:56:06 MASTER-Kislovodsk robotic telescope located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) was pointed to the SWIFT GRB181202.28 32902 sec after trigger time at 2018-12-02 15:46:09 UT, with upper limit up to 20.2 mag. No OT detected. The observations began at zenit distance = 57 deg. The sun altitude is -23.0 deg. This message can be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23496 SUBJECT: GRB 181202A: RATIR Optical and NIR Observations DATE: 18/12/03 17:27:42 GMT FROM: Alan M. Watson at Instituto de Astronomia UNAM Alan M. Watson (UNAM), Nat Butler (ASU), Alexander Kutyrev (GSFC), William H. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UVI), Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), Jesús González (UNAM), Carlos Román-Zúñiga (UNAM), Harvey Moseley (GSFC), John Capone (UMD), V. Zach Golkhou (U. Wash.), and Vicki Toy (UMD) report: We observed the field of GRB 181202A (Cannizzo et al., GCN 23482) with the Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the 1.5m Harold Johnson Telescope at the Observatorio Astronómico Nacional on Sierra San Pedro Mártir from 2018/12 3.09 to 2018/12 3.11 UTC (19.43 to 20.04 hours after the BAT trigger), obtaining a total of 0.09 hours exposure in the r and i bands and 0.12 hours exposure in the Z, Y, J, and H bands in poor conditions. For a source within the Swift-XRT error circle, in comparison with the USNO-B1 and 2MASS catalogs, we obtain the following 3-sigma upper limits: r > 19.18 i > 19.17 Z > 16.52 Y > 16.30 J > 16.00 H > 16.31 These magnitudes are in the AB system and are not corrected for Galactic extinction in the direction of the GRB. However, we note that in our optimally-combined all-filter image, there appears to be a very faint source present in the Swift-XRT error circle. This suggests that there may be a source present at low significance in at least some of our individual images. We thank the staff of the Observatorio Astronómico Nacional in San Pedro Mártir. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 23498 SUBJECT: GRB 181202A: Swift/UVOT Detection DATE: 18/12/04 00:09:57 GMT FROM: Mike Siegel at PSU/Swift MOC M. H. Siegel (PSU) and J. K. Cannizzo (NASA/UMBC) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 181202A 86 s after the BAT trigger (Cannizzo et al., GCN Circ. 23482). A source consistent with the XRT position (Evans et al. GCN Circ. 23483) is detected in the initial UVOT exposures. The preliminary UVOT position is: RA (J2000) = 18:42:56.38 = 280.73491 (deg.) Dec (J2000) = +27:57:35.0 = 27.95971 (deg.) with an estimated uncertainty of 0.47 arc sec. (radius, 90% confidence). Preliminary detections and 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag v 623 1540 117 >18.7 b 342 591 246 19.57 +/- 0.18 u (fc) 86 336 246 17.67 +/- 0.07 w1 672 1441 97 >19.6 m2 647 1560 112 >22.2 w2 598 1516 117 >20.5 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.14 in the direction of the burst (Schlegel et al. 1998).