//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15699 SUBJECT: GRB 140108A: Swift detection of a burst DATE: 14/01/08 17:29:05 GMT FROM: David Palmer at LANL J. L. Racusin (NASA/GSFC), S. D. Barthelmy (GSFC), M. G. Bernardini (INAF-OAB), P. D'Avanzo (INAF-OAB), J. A. Kennea (PSU), A. Melandri (INAF-OAB), D. M. Palmer (LANL), M. H. Siegel (PSU), E. Sonbas (NASA/GSFC/Adiyaman Univ.), E. Troja (NASA/GSFC/UMCP) and T. N. Ukwatta (MSU) report on behalf of the Swift Team: At 17:18:42 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 140108A (trigger=583338). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 325.178, +58.766 which is RA(J2000) = 21h 40m 43s Dec(J2000) = +58d 45' 58" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows several peaks at T+5, T+35, and T+85 sec with a total duration of about 120 sec. The peak count rate was ~8000 counts/sec (15-350 keV), at ~6 sec after the trigger. The XRT began observing the field at 17:19:51.1 UT, 68.7 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 325.1106, 58.7437 which is equivalent to: RA(J2000) = +21h 40m 26.54s Dec(J2000) = +58d 44' 37.3" with an uncertainty of 4.9 arcseconds (radius, 90% containment). This location is 149 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 2.5 s image was 3.34e-09 erg cm^-2 s^-1 (0.2-10 keV). UVOT took a finding chart exposure of 150 seconds with the White filter starting 78 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 19.6 mag. The 8'x8' region for the list of sources generated on-board covers 100% of the XRT error circle. The list of sources is typically complete to about 18 mag. No correction has been made for the large, but uncertain extinction expected. Burst Advocate for this burst is J. L. Racusin (judith.racusin AT 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: 15700 SUBJECT: GRB 140108A: Prompt enhanced Swift-XRT position DATE: 14/01/08 18:05:49 GMT FROM: Phil Evans at U of Leicester P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team: Using promptly downlinked XRT event data for GRB 140108A, we find an enhanced XRT position of the afterglow: RA, Dec: 325.1127, 58.7446 which is equivalent to: RA (J2000) = 21 40 27.04 Dec (J2000) = +58 44 40.7 with an uncertainty of 2.1 arcseconds (radius, 90% confidence). Analysis of the promptly available data is online at http://www.swift.ac.uk/sper/583338. Position enhancement is is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, MNRAS, 397, 1177). This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15701 SUBJECT: GRB 140108A: MASTER-Net OT detection DATE: 14/01/08 18:08:50 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs E. Gorbovskoy, V. Lipunov, D.Denisenko, V.Kornilov, D.Kuvshinov, N.Tyurina, P.Balanutsa, A.Kuznetsov Sternberg Astronomical Institute, Moscow State University A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik Kislovodsk Solar Station of the Pulkovo Observatory V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov Blagoveschensk Educational State University, Blagoveschensk K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk Irkutsk State University V.Krushinski, I.Zalozhnih, A. Popov Ural Federal University, Kourovka Hugo Levato and Carlos Saffe Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE) Claudio Mallamaci, Carlos Lopez and Federico Podest Observatorio Astronomico Felix Aguilar (OAFA) MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in Kislovodsk was pointed to the GRB140108A 22 sec after notice time and 39 sec after trigger time at 2014-01-08 17:19:21.913 UT in two polarizations. On our first (10s exposure) set we haven`t found optical transient within SWIFT error-box ( Racusin et al. GCN 15699 ). The 5-sigma upper limit has been about 17.0 mag. MASTER II robotic telescope located in Blagoveschensk was pointed to the GRB140108A 30 sec after notice time and 47 sec after trigger time at 2014-01-08 17:19:29.211 UT in two polarizations. On our first (10s exposure) set we haven`t found optical transient within SWIFT error-box. The 5-sigma upper limit has been about 16.0 mag. The polarizations filters oriented by RA and DEC axis (0 and 90 degrees from RA axis) in Kislovodsk, and 45 and 135 degrees from RA axis in Blagoveschensk. The OT candidate apeared in two sites (Blagoveschensk and Kislovodsk) and at 2014-01-08 17:19:42 at position: (J2000) RA = 21 40 26.77 Dec = +58 44 41.4 Error=+-1 arcsc sigma The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15702 SUBJECT: GRB 140108A: 1.23m CAHA observations DATE: 14/01/08 18:17:29 GMT FROM: Javier Gorosabel at IAA-CSIC J. Gorosabel (UPV/EHU-IAA/CSIC), R. Hueso (UPV/EHU), M. Fernandez (IAA/CSIC) on behalf of a larger collaboration report: We observed the field of GRB 140108A (Racusin et al., GCN 15699) with the 1.23m CAHA telescope. An object with I~19 is detected at 17:55 UT coincident with the optical candidate position reported by Gorbovskoy et al. (GCN 15701). Further observations are in progress. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15703 SUBJECT: GRB 140108A: D50+BART optical candidate detection DATE: 14/01/08 18:27:38 GMT FROM: Jan Strobl at AI AS CR,Ondrejov Jan Strobl (1,3), Martin Jelinek (2), Cyril Polasek (1), Michal Jakubec (1), Petr Skala (1,3) and Rene Hudec (1,3) (1. AI ASCR Ondrejov, 2. IAA CSIC Granada, 3. FEE CTU Prague) We observed the field of the Swift GRB 140108A (Racusin et al., GCNC 15699) with the 0.5m telescope D50 and 0.25m telescope BART in Ondrejov (Czech Republic), starting at 17:19:20 UT, i.e. 36s after the trigger. We detect a new variable and uncatalogued object within the XRT coordinates 21:40:26.813 +58:44:40.17 (J2000) +-1". Preliminary photometry provides brightness of R~18.0 300s after the GRB trigger. This message can be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15704 SUBJECT: GRB 140108A: Mondy optical observations DATE: 14/01/08 19:07:34 GMT FROM: Alexei Pozanenko at IKI, Moscow E. Klunko (ISTP), M. Eselevich(ISTP), A. Volnova (IKI), A. Pozanenko(IKI) report on behalf of larger GRB follow-up collaboration: We observed the field of the Swift GRB 140108A (Racusin et al., GCN 15699) with AZT-33IK telescope of Sayan observatory (Mondy) starting Jan., 08 (UT) 17:24:55. We obtained several images in R-filter with exposure of 20,60 and 180 seconds. Within the enhanced XRT circle (Evans et al., GCN 15700) we detected optical afterglow (Gorbovskoy et al., GCN 15701; Gorosabel et al., 15702) The position of the afterglow coincids with previously reported (Gorbovskoy et al., GCN 15701; Strobl et al., 15703). At (UT) 17:32, i.e. ~13.5 min. after GRB trigger the R-magnitude of the afterglow is ~19.2. The finding chart can be found in http://grb.rssi.ru/GRB140108A/GRB140108A_AZT33IK_2014-01-08T_17-30-34.png Observation is continuing. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15705 SUBJECT: GRB 140108A: Enhanced Swift-XRT position DATE: 14/01/08 22:00:31 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 634 s of XRT Photon Counting mode data and 1 UVOT images for GRB 140108A, 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 = 325.11211, +58.74464 which is equivalent to: RA (J2000): 21h 40m 26.91s Dec (J2000): +58d 44' 40.7" 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: 15706 SUBJECT: GRB 140108A: Swift-XRT refined Analysis DATE: 14/01/09 08:12:15 GMT FROM: Paolo D'Avanzo at INAF-OAB P. D'Avanzo (INAF-OAB), J. L. Racusin (NASA/GSFC), P. A. Evans (U. Leicester) report on behalf of the Swift-XRT team: We have analysed 10 ks of XRT data for GRB 140108A (Racusin et al. GCN Circ. 15699), from 58 s to 41.8 ks after the BAT trigger. The data comprise 2.4 ks in Windowed Timing (WT) mode (the first 8 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 15705). The light curve shows some initial flaring activity, with the flares peaking at around 90 and 220 s after the trigger. The underlying emission can be modelled with a series of power-law decays. The initial decay index is alpha=2.8 (+/-0.7). At T+184 s the decay flattens to an alpha of 0.52 (+/-0.03) before breaking again at T+7014 s to a final decay with index alpha=1.20 (+0.08, -0.07). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.69 (+0.04, -0.03). The best-fitting absorption column is consistent with the Galactic value of 7.0 x 10^21 cm^-2 (Kalberla et al. 2005). The PC mode spectrum has a photon index of 1.91 (+0.16, -0.15) and a best-fitting absorption column of 9.3 (+1.3, -1.2) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 5.7 x 10^-11 (1.1 x 10^-10) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 9.3 (+1.3, -1.2) x 10^21 cm^-2 Galactic foreground: 7.0 x 10^21 cm^-2 Excess significance: 3.1 sigma Photon index: 1.91 (+0.16, -0.15) If the light curve continues to decay with a power-law decay index of 1.20, the count rate at T+24 hours will be 0.035 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.0 x 10^-12 (3.8 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/00583338. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15707 SUBJECT: GRB 140108A: theoretical prediction of redshift and of supernova occurrence DATE: 14/01/09 11:47:54 GMT FROM: Remo Rufinni at ICRA R. Ruffini, C.L. Bianco, M. Enderli, M. Kovacevic, M. Muccino, A.V. Penacchioni, G.B. Pisani, J.A. Rueda, Y. Wang report: The late Swift/XRT observations of GRB 140108A (1,2) evidences the fullfillment of the IGC paradigm (3,4). A preliminary overlapping of its X-ray (0.3-10 keV in rest-frame) luminosity with the one of GRB 090618, namely an IGC prototype (5), gives an estimate of the redshift of z=0.6 (+/- 0.1) (see Fig. 1 ). As a consequence, a supernova associated to GRB 140108A is expected to emerge after 16 (+/- 3) days after the trigger. Given the spectral parameters of the prompt emission by Swift/BAT (), this redshift estimation leads to an isotropic energy of E_iso ~ 4x10^52 erg. Continuous monitoring and complementary observations in all possible wavelengths are encouraged. References: (1) Racusin et al., GCN 15699 (2) D'Avanzo et al., GCN 15706 (3) Rueda & R. Ruffini, ApJLett, 758, L7 (2012) (4) Pisani et al., A&A, 552, L5 (2013) (5) Izzo et al., A&A, 548, L5 (2012) //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15708 SUBJECT: GRB 140108A: Swift/UVOT Detection DATE: 14/01/09 12:31:27 GMT FROM: Alice Breeveld at MSSL-UCL A. A. Breeveld (UCL-MSSL) and J. L. Racusin (NASA/GSFC) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 140108A 78 s after the BAT trigger (Racusin et al., GCN Circ. 15699). A fading source consistent with the optical position (Gorbovskoy et al. GCN Circ. 15701, Strobl et al. GCN Circ. 15703) is detected in the initial UVOT exposures. The preliminary detection and 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the finding chart (FC) and other early exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white_FC 78 228 147 20.17 ± 0.20 white 571 1021 189 >21.3 v 621 1420 97 >18.9 b 547 1345 78 >19.8 u 291 1320 304 >20.6 w1 670 1462 90 >20.3 m2 646 1444 97 >19.8 w2 596 1395 83 >20.2 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 1.00 in the direction of the burst (Schlegel et al. 1998). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15709 SUBJECT: GRB 140108A: Fermi GBM detection DATE: 14/01/09 14:10:59 GMT FROM: George A. Younes at USRA/NASA/MSFC G. Younes (USRA/NASA-MSFC) reports on behalf of the Fermi GBM Team: At 17:18:42.99 UT on 08 January 2014, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 140108A (trigger 410894325/140108721), which was also detected with Swift (J. L. Racusin et al., GCN 15699). The GBM on-ground location is consistent with the Swift/XRT location of the burst (P. Evans et al., GCN 15705). The angle to the Fermi LAT boresight is 87 degrees from the Swift XRT position. The GBM light curve consists of a multiple-peak structure with a duration (T90) of about 95 s (50-300 keV). The time-averaged spectrum from T0 to T0+105 s is adequately fit by a Comptonized function with Epeak = 240 +/- 23 keV, and an index alpha = -1.24 +/- 0.04. The event fluence (10-1000 keV) in this time interval is (1.905 +/- 0.069)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+85 s in the 10-1000 keV band is 10.3 +/- 0.3 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15710 SUBJECT: GRB 140108A: Swift-BAT refined analysis DATE: 14/01/09 14:22:08 GMT FROM: Scott Barthelmy at NASA/GSFC J. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (NASA/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), J. L. Racusin (NASA/GSFC), T. Sakamoto (AGU), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU) (i.e. the Swift-BAT team): Using the data set from T-239 to T+963 sec from recent telemetry downlinks, we report further analysis of BAT GRB 140108A (trigger #583338) (Racusin, et al., GCN Circ. 15699). The BAT ground-calculated position is RA, Dec = 325.129, 58.749 deg, which is RA(J2000) = 21h 40m 30.9s Dec(J2000) = +58d 44' 55.3" with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 71%. The mask-weighted light curve shows two main peaks; the first starting at ~T-25 sec, peaking at ~T+7 sec, and almost returns to background at T+20 sec. The second peak starts at ~T+70 sec, peaks at ~T+77 sec, and ends at ~T+110 sec with some weak emission (2-3 sigma) out to ~T+150 sec. T90 (15-350 keV) is 97.8 +- 3.3 sec (estimated error including systematics). The time-averaged spectrum from T-24.8 to T+103.3 sec (with 2.5 sec of missing data in the middle of the 2nd peak) is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.60 +- 0.05. The fluence in the 15-150 keV band is 6.3 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+6.49 sec in the 15-150 keV band is 6.1 +- 0.3 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/583338/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15713 SUBJECT: GRB 140108A: Mondy optical upper limit DATE: 14/01/10 12:39:53 GMT FROM: Alina Volnova at SAI MSU A. Volnova (IKI), E. Klunko (ISTP), M. Eselevich(ISTP), A. Pozanenko(IKI) report on behalf of larger GRB follow-up collaboration: We observed the field of the Swift GRB 140108A (Racusin et al., GCN 15699) with AZT-33IK telescope of Sayan observatory (Mondy) starting Jan., 09 (UT) 15:10:20. We obtained several images in R-filter with exposure of 180 seconds. On the stacked image we do not detected the optical afterglow (Gorbovskoy et al., GCN 15701; Gorosabel et al., 15702). The details of the photometry are the following: UT start, t-T0 Filter Exp. OT UL (mid, days) (s) (3 sigma) 15:10:20 0.94627 R 34*180 n/d 22.0 The photometry is based on 3 USNO-B1.0 stars: USNO-B id RA Dec R2 1487-0322168 21:40:30.85 +58:43:53.1 18.18 1487-0322049 21:40:20.16 +58:43:58.3 17.96 1487-0322069 21:40:21.62 +58:45:00.6 17.29 //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15717 SUBJECT: GRB 140108A BAT refined analysis update DATE: 14/01/10 16:28:23 GMT FROM: Jay R. Cummings at NASA/GSFC/Swift J. R. Cummings reports on behalf of the Swift-BAT team: There were some small gaps in the data used in the BAT refined analysis of GRB 140108A (Cummings et. al, GCN circ # 15710). With a complete data set, T90 is slightly shorter, 94 +- 4 seconds, the photon index for the simple power-law fit to the spectrum is slightly larger, 1.62 +- 0.05, and the total fluence is slightly larger, (7.0 +- 0.2) x 10^-7 ergs/cm^2. The energy interval is 15-150 keV and uncertainties are 90% confidence. In the lightcurve, the second peak is a little larger than it looked before, and is very similar to the first peak. The updated results have been posted at: http://gcn.gsfc.nasa.gov/notices_s/583338/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15718 SUBJECT: GRB 140108A BAT refined analysis update *CORRECTION* DATE: 14/01/10 17:27:59 GMT FROM: Jay R. Cummings at NASA/GSFC/Swift My apologies; I made a typographical error in the posted update, GCN Circ. #15717. The total fluence should be (7.0 +- 0.2) x 10^-6 ergs/cm^2. The corrected circular text is below: J. R. Cummings reports on behalf of the Swift-BAT team: There were some small gaps in the data used in the BAT refined analysis of GRB 140108A (Cummings et. al, GCN circ # 15710). With a complete data set, T90 is slightly shorter, 94 +- 4 seconds, the photon index for the simple power-law fit to the spectrum is slightly larger, 1.62 +- 0.05, and the total fluence is slightly larger, (7.0 +- 0.2) x 10^-6 ergs/cm^2. The energy interval is 15-150 keV and uncertainties are 90% confidence. In the lightcurve, the second peak is a little larger than it looked before, and is very similar to the first peak. The updated results have been posted at: http://gcn.gsfc.nasa.gov/notices_s/583338/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15723 SUBJECT: GRB 140108A: Suzaku WAM observation of the prompt emission DATE: 14/01/11 15:12:08 GMT FROM: Tetsuya Yasuda at Saitama U T. Yasuda, M. Tashiro, Y. Terada, Y. Ishida, H. Ueno, S. Sugimoto (Saitama U.), M. Yamauchi, N. Ohmori, M. Akiyama, R. Kinoshita (Univ. of Miyazaki), M. Ohno, K. Takaki, T. Kawano, R. Nakamura, S. Furui, Y. Fukazawa (Hiroshima U.), K. Yamaoka (Nagoya U.), S. Sugita (Ehime U.), Y. E. Nakagawa, M. Kokubun, T. Takahashi (ISAS/JAXA), W. Iwakiri(RIKEN), Y. Hanabata (ICRR), Y. Urata (NCU), K. Nakazawa, K. Makishima (Univ. of Tokyo) on behalf of the Suzaku WAM team, report: The long GRB 140108A (Swift/BAT trigger #583338; Racusin et al., GCN 15699) triggered the Suzaku Wide-band All-sky Monitor (WAM) which covers an energy range of 50 keV - 5 MeV at 17:18:48.879 UT (=T0). The observed light curve shows a multi-peaked structure starting at T0-11 s, ending at T0+104 s with a duration (T90) of about 90 seconds. The fluence in 100 - 1000 keV was 1.19 (+0.12/-0.50) x 10^-5 erg/cm^2. The 1-s peak flux measured from T0+79 s was 4.70 (+0.14/-1.81) photons/cm^2/s in the same energy range. Preliminary result shows that the time-averaged spectrum from T0-11 s to T0+104 s is well fitted by a power-law with exponential cutoff model: dN/dE ~ E^{-alpha} * exp(-(2-alpha)*E/Epeak) with alpha 0.70 (+0.68/-0.85), and Epeak 427 (+137/-72) keV (chi^2/d.o.f. = 5.8/10). All the quoted errors are at statistical 90% confidence level. The light curves for this burst are available at: http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15727 SUBJECT: GRB 140108A: Konkoly optical observations DATE: 14/01/13 18:20:17 GMT FROM: Janos Kelemen at Konkoly Obs/Hungary J. Kelemen (kelemen at konkoly.hu) on behalf of the GRB OT observing program at the Konkoly Observatory. Starting on the evening of 08/01/2014 we observed the field of GRB 140108A (Racusin et al., GCN 15699) 8802 sec. after the burst, using a 60/90/180 cm Schmidt telescope located at the Mountain Station of the Konkoly Observatory, equipped with an Apogee CCD camera through R filter. On the coadded R images (total exp.time 900 sec) we marginally detected the OT at the position indicated the finding chart provided by Pozarenko, GCN 15704. Based on the nearby UCAC-4 stars we provide 22.6 +/- 0.3 magnitude in the R band for the OT. time from GRB. exp filter Mag. 8802 s. 900 s R 22.6 +/-0.3 //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 15744 SUBJECT: GRB 140108A: Mondy optical observations, refined analysis DATE: 14/01/15 17:37:02 GMT FROM: Alexei Pozanenko at IKI, Moscow A.Volnova (IKI), E. Klunko (ISTP), M. Eselevich(ISTP), A. Pozanenko(IKI) report on behalf of larger GRB follow-up collaboration: We analyzed observations of AZT-33IK telescope of Sayan observatory, Mondy (Klunko et al., GCN 15704; Volnova et al., GCN 15713) of the Swift GRB 140108A (Racusin et al., GCN 15699). Using bright time interval of the afterglow we calculated coordinates of the OT: RA(J2000)= 21:40:26.75 RA(J2000)= +58:44:41.3 with uncertainty of 0.4 arcsec of each coordinate. The OT coordinates are within the enhanced XRT position (Osborne et al., GCN 15705) and compatible with positions reported early (Gorbovskoy et al., GCN 15701; Strobl et al., 15703). The light curve of the afterglow can be found in http://grb.rssi.ru/GRB140108A/GRB140108A_lc_preliminary.png. The photometry is based on USNO-B1.0 stars: s1 1487-0322168 21:40:30.85 +58:43:53.1 18.18 s2 1487-0322049 21:40:20.16 +58:43:58.3 17.96 s3 1487-0322069 21:40:21.62 +58:45:00.6 17.29 s4 1487-0322305 21:40:41.61 +58:45:28.0 15.73 Maximum of afterglow brightness of R=18.50 +/- 0.08 was detected at 0.00468 days after GRB trigger. It is also interesting a sharp drop at ~0.85 days (confirmed by observations reported by Kelemen (GCN 15727)) which could be related to a jet break observed in XRT light curve (see http://www.swift.ac.uk/xrt_live_cat/00583338/).