//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 16653 SUBJECT: GRB 140801A (FERMI trigger 428612396): MASTER brigth OT discovery DATE: 14/08/01 20:52:09 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs E. Gorbovskoy, V. Lipunov, D.Denisenko, M.Pruzhinskaya, V.Kornilov, D.Kuvshinov, A.Belinski, N.Tyurina, N.Shatskiy, P.Balanutsa, D.Zimnukhov, A.Kuznetsov, V.V.Chazov, A.Sankovich Lomonosov Moscow State University, Sternberg Astronomical Institute, Moscow State University K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk Irkutsk State University V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov Blagoveschensk Educational State University, Blagoveschensk A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik Kislovodsk Solar Station of the Pulkovo Observatory V.Krushinsky, I.Zalozhnih, A. Popov Ural Federal University, Yekaterinburg, 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 Tunka was pointed to the GRB140801A (FERMI trig. 428612396) 54 sec after notice time and 100 sec after trigger time at 2014-08-01 19:01:33 UT in two polarizations. MASTER-Tunka auto-detection system discovered bright OT source at (RA, Dec) = 02h 56m 16.44s +30d 56m 16.8s on 2014-08-01.79376 UT. The OT unfiltered magnitude is 14.6m (limit 18.3m) within FERMI error-box (trig. N 428612396). Preliminary automatic photometry and astrometry Date Time Ra Dec Mag 2014-08-01 19:01:31.886 02h 56m 16.42s , +30d 56m 16s.8 14.64 2014-08-01 19:03:02.863 02h 56m 16.43s , +30d 56m 17s.0 15.72 2014-08-01 19:04:38.384 02h 56m 16.43s , +30d 56m 17s.0 16.30 Our band is well described by a parity 0.8R+0.2B (USNO B1). The discovery and reference images are available at: http://master.sai.msu.ru/static/GRB/GRB140801_FERMI.png The 5-sigma upper limit has been about 18.53mag The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 16654 SUBJECT: GRB 140801A: archival upper limits on the host galaxy DATE: 14/08/01 22:09:55 GMT FROM: Denis Denisenko at SAI MSU D. Denisenko, E. Gorbovskoy, V. Lipunov (Sternberg Astronomical Institute, Moscow State University) report: Since the error box of GRB 140801A (FERMI trigger 428612396) was not covered by Sloan Digital Sky Survey, we have used the digitized Palomar plates of this area to create the color-combined finder chart and to estimate the upper limits on the host galaxy of this burst. There are in total 12 plates available (POSS-I red and blue ones from 1953 and 1954, two Quick-V plates from 1982 and six POSS-II plates from 1991-1995: 2 blue, 2 red and 2 infrared). There is nothing at the position of MASTER optical transient (Gorbovskoy et al., GCN 16653) on any individual plates, as well as on their combination to the limiting magnitude ~22.5. 5'x5' color-combined finder chart centered at MASTER OT J025616.43+305617.0 is uploaded to http://master.sai.msu.ru/static/GRB/GRB140801A-BRIR5x5.jpg (position of the OT is marked with dashes). We also note the nearby white dwarf 44" north of the OT which is marked by an arrow. It has the following entries in the major catalogues: USNO-B1.0 1209-0038230 (02 56 16.581 +30 57 02.09 pmRA=88 pmDE=32 B1=15.37 R1=15.54 B2=15.74 R2=16.06 I=16.20) GALEX J025616.6+305702 (FUV=15.09+/-0.02 NUV=15.41+/-0.01) 2MASS J02561657+3057017 (J=16.12+/-0.09) There is no mention of its variability in the literature. However, it should be used with caution in photometric purposes. This message can be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 16655 SUBJECT: IPN triangulation of GRB 140801A (Fermi trigger 428612396) DATE: 14/08/01 22:25:55 GMT FROM: Kevin Hurley at UCBerkeley/SSL K. Hurley, on behalf of the IPN team, S. Golenetskii, R. Aptekar, V. Pal'shin, D. Frederiks, D. Svinkin, and T. Cline on behalf of the Konus-Wind team, J. Goldsten, on behalf of the MESSENGER NS GRB team, and V. Connaughton, M. S. Briggs, C. Meegan, and V. Pelassa, on behalf of the Fermi GBM team, report: GRB140801A (Fermi trigger 428612396) has been observed by Konus-Wind, Fermi-GBM, and MESSENGER, so far, at around 68393 SOD (18:59:53) UT. We have triangulated it to a preliminary, 3 sigma annulus centered at RA, Dec (2000)=123.886, +21.098 degrees, whose radius is 70.951 +/- 0.125 degrees. The bright MASTER OT (Gorbovskoy et al. GCN 16653) lies 0.0093 degrees from the center line of this annulus, and is therefore likely to be the optical afterglow of this GRB. A map has been posted at ssl.berkeley.edu/ipn3/140801A. This localization may be improved. The spectral and temporal properties of this GRB will be given in forthcoming GCN Circulars. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 16656 SUBJECT: GRB 140801A: NOT afterglow confirmation DATE: 14/08/02 03:34:21 GMT FROM: Dong Xu at DARK/NBI D. Xu (DARK/NBI), S. Schulze (PUC, MAS), M. El-Souri, S. Boye Nissen, M. Sparre, J. P. U. Fynbo (DARK/NBI), A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), P. Jakobsson (U. Iceland) report on behalf a larger collaboration: We observed the field of GRB 140801A (Fermi trigger 428612396) with the 2.5-m Nordic Optical Telescope (NOT) equipped with ALFOSC. We obtained a 200-s exposure in each of V, R, and I bands. Observations started at 01:07:23 UT on August 2 (i.e. 6.12 hours after the burst). The optical transient reported by Gorbovskoy et al. (GCN 16653) is clearly detected in each of our images at the same position. And it has decayed to R(Vega) ~ 20.6 mag at 6.15 hours post-trigger, calibrated against two bright nearby USNO B1 stars. This measurement is not corrected for foreground extinction. The OT roughly decays as t^-1.5 during the MASTER observations (GCN 16653), and then changes to roughly as t^-0.9 assuming a simple power-law decline since the MASTER's end-time. The whole behavior is similar to that of previous GRB optical afterglows. We thus conclude that this OT is very likely the optical afterglow of GRB 140801A. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 16657 SUBJECT: GRB 140801A: Redshift from the 10.4m GTC telescope DATE: 14/08/02 04:56:21 GMT FROM: Antonio de Ugarte Postigo at IAA-CSIC A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), J. Gorosabel (IAA-CSIC, UPV/EHU), C.C. Thoene (IAA-CSIC), J.P.U. Fynbo (DARK/NBI), D. Xu (DARK/NBI), D. Perez-Valladares (GTC), and G. Gomez-Velarde (ULL-IAC, GTC) report on behalf of a larger collaboration: We have observed the afterglow of the Fermi GRB140801A (Gorbovskoy et al. GCN 16653, Xu et al. GCN 16655) with the 10.4m GTC (+OSIRIS). Spectroscopic observations began at 3:35 UT (8.59 hr after the burst). The first 900 s spectrum was obtained with the R1000B grism, and covered the range between 3630 and 7500 A, at a resolution of ~1000. We detect a strong continuum with absorption features that correspond to NiII, MnII, FeII, MgII, and MgI at a common redshift of z=1.320, which we identify as the redshift of the GRB. Further spectroscopic observations are ongoing. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 16658 SUBJECT: GRB 140801A: Fermi GBM observation DATE: 14/08/02 05:37:24 GMT FROM: Veronique Pelassa at UAH V. Pelassa (UAH) reports on behalf of the Fermi GBM Team: "At 18:59:53.26 UT on 1 August 2014, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 140801A (trigger 428612396 / 140801792). An optical transient was detected by the MASTER II robotic telescope (Lipunov et al. 2014, GCN 16653). The GBM on-ground location is consistent with the OT location, which angle from the Fermi LAT boresight is 80 degrees. The GBM light curve consists of two bright pulses followed by a short tail, with a duration (T90) of about 7 s (50-300 keV). The time-averaged spectrum from T0-2.048 s to T0+12.288 s is well fit by a power law function with an exponential high-energy cutoff. The power law index is -0.42 +/- 0.03 and the cutoff energy, parameterized as Epeak, is 125 +/- 2 keV (Castor-statistics 697.99 for 610 d.o.f.). A Band function fits the spectrum equally well (Castor-statistics 695.14 for 609 d.o.f.) with Epeak= 122 +/- 3 keV, alpha = -0.40 +/- 0.04 and beta = -3.6 +/- 0.4. The event fluence (10-1000 keV) in this time interval is (1.22 +/- 0.01)E-05 erg/cm^2. The 1.024-sec peak photon flux measured starting from T0+0.832 s in the 10-1000 keV band is 22.6 +/- 0.4 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: 16659 SUBJECT: GRB 140801A : Virtual Telescope optical observations DATE: 14/08/02 09:44:48 GMT FROM: Gianluca Masi at Bellatrix Astronomical Obs G. Masi, the Virtual Telescope Project - Italy, reports: I observed the field of GRB 140801A (Fermi trigger 428612396) with with the 17" robotic unit part of the Virtual Telescope (Ceccano, Italy) at 2 Aug. 2014, 00:10:39 UT, 5.15 hours seconds after the burst. An optical source is visible where described by Gorbovskoy et al. (GCN 16653) and D. Xu et al (GCN 16656) in a image coming from the sum of three, 180-seconds exposures, unfiltered. The position of the source is RA: 02 56 16.46 +30 56 17.9 (J2000.0, mean residuals of 0.2") and the magnitude was estimated to be 19.6, assuming R mags for the reference stars from UCAC-4. The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 16660 SUBJECT: Konus-Wind observation of GRB 140801A DATE: 14/08/02 12:26:02 GMT FROM: Dmitry Frederiks at Ioffe Institute S. Golenetskii, R.Aptekar, D. Frederiks, V. Pal'shin, P. Oleynik, M. Ulanov, D. Svinkin, A. Tsvetkova, A.Lyssenko, and T. Cline on behalf of the Konus-Wind team, report: The long-duration GRB 140801A (IPN triangulation: Hurley et al., GCN 16655; Fermi-GBM detection: Pelassa, GCN 16658) triggered Konus-Wind at T0=68394.769 s UT (18:59:54.769). The light curve shows a multi-peaked structure with a total duration of ~7.5 s. The emission is seen up to ~3 MeV. As observed by Konus-Wind, the burst had a fluence of 1.10(-0.04,+0.04)x10^-5 erg/cm2, and a 64-ms peak flux, measured from T0+0.128 s, of 4.6(-0.6,+0.6)x10^-6 erg/cm2/s (both in the 20 keV - 10 MeV energy range). The time-averaged spectrum (measured from T0 to T0+7.680 s) is best fit in the 20 keV - 5 MeV range by the cutoff power law with the following model parameters: the photon index alpha = -0.44(-0.17,+0.18), and the peak energy Ep = 108(-4,+5) keV, chi2 = 75/71 dof. Fitting this spectrum with the Band model yields the same values of alpha and Ep with an upper limit on beta of -4.2 The spectrum near the peak count rate (measured from T0 to T0+0.256 s) is best fit in the 20 keV - 5 MeV range by the cutoff power law with the following model parameters: the photon index alpha = +0.38(-0.56,+0.69), and the peak energy Ep = 121(-12,+13) keV, chi2 = 27/24 dof. Assuming the redshift z=1.320 (de Ugarte Postigo et al., GCN 16657) and a standard cosmology model with H_0 = 70 km/s/Mpc, Omega_M = 0.27, and Omega_Lambda = 0.73, we estimate the following rest-frame parameters: the isotropic energy release E_iso is ~4.9x10^52 erg, the peak luminosity L_iso is ~5.0x10^52 erg/s, and the rest-frame peak energy of the time-integrated spectrum, Ep,i, is ~250 keV. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB140801_T68394/ All the quoted errors are at the 90% sigma confidence level. All the quoted values are preliminary. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 16661 SUBJECT: GRB 140801A: Swift-XRT observations DATE: 14/08/02 14:20:53 GMT FROM: Alessandro Maselli at INAF/IASF Palermo A. Maselli and M. De Pasquale (INAF-IASFPA) report on behalf of the Swift-XRT team: We have analysed 2.0 ks of XRT data for the FERMI/GBM detected burst GRB 140801A (Pelassa, GCN Circ. 16658), from 36.4 ks to 48.0 ks after the GBM trigger. The data are entirely in Photon Counting (PC) mode. An X-ray source is found at the position of the optical transient detected by MASTER (Gorbovskoy et al., GCN Circ. 16653). Using 1893 s of PC mode data and 2 UVOT images, we find an enhanced XRT position (using the XRT-UVOT alignment and matching UVOT field sources to the USNO-B1 catalogue): RA, Dec = 44.06877, +30.93799 which is equivalent to: RA (J2000): 02h 56m 16.50s Dec(J2000): +30d 56' 16.8" with an uncertainty of 2.5 arcsec (radius, 90% confidence). This position is 0.8 arcsec from the MASTER position. We believe that this source, which has a mean count rate of 2.3e-02 ct/sec, is the X-ray afterglow of GRB 140801A but further observations are needed to determine a decaying behaviour. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00020402. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 16662 SUBJECT: GRB 140801A: Swift/UVOT Upper Limits DATE: 14/08/02 18:10:39 GMT FROM: Lea Hagen at PSU L. M. Z. Hagen (PSU) and E. Troja (NASA/GSFC/UMCP) report on behalf of the Swift/UVOT team: The Swift/UVOT observed the field of the Fermi/GBM-detected burst GRB 140801A beginning 36.4 ks after the trigger (Pelassa, GCN Circ. 16658). No optical afterglow consistent with the XRT candidate (Maselli, GCN Circ. 16661) or MASTER candidate (Gorbovskoy et al., GCN Circ. 16653) 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 initial exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag uvw1 36391 47996 1944 >20.70 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.226 in the direction of the burst (Schlegel et al. 1998). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 16663 SUBJECT: GRB 140801A: BTA confirmation of redshift DATE: 14/08/02 19:11:44 GMT FROM: Vladimir Sokolov at SAO RAS A. Moskvitin, V. Komarova, T. Sokolova (SAO RAS), A. J. Castro-Tirado (IAA-SCIC), J. Gorosabel (IAA-SCIC, UPV/EHU), S. B. Pandey (ARIES), M. Glushkov (KFU), S. Boronina (SPbSU), report on behalf of the larger collaboration: At the night of August 1/2 we observed the GRB 140801A field (Fermi trigger 428612396) with BTA/Scorpio-I. Observations started at 21:10 UT (2.17 hours after the GRB). The optical transient (Gorbovskoy et al., GCNC 16653; Xu et al., GCNC 16656, Masi, GCNC 16659) is clearly detected in our V and Rc images with the brightness R = 20.2 (2.85 hours after the trigger). Photometry is based on the USNO-B1 star with the coordinates R. A. = 02:56:16.58, Dec. = +30:57:02.1 and R2 = 16.06. The OT magnitude was not corrected for the Galactic extinction E(B-V) = 0.09 in the direction of the object. We also obtained an OT spectrum and measured the redshift on basis of several lines. Our value z =1.319 +/- 0.003 is in a good agreement with that by de Ugarte Postigo et al. (GCNC 16657). We thank T. Fatkhullin for his great assistance in observations. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 16665 SUBJECT: GRB140801A: Swift/XRT further observations DATE: 14/08/03 14:05:25 GMT FROM: Alessandro Maselli at INAF/IASF Palermo A. Maselli, M. De Pasquale (INAF-IASFPA) and E. Troja (NASA/GSFC/UMCP) report on behalf of the Swift-XRT team: We report on further Swift XRT observations in the field of the FERMI/GBM-discovered GRB 140801A (Pelassa, GCN Circ. 16658). A new exposure of 2.0 ks has been obtained, 123 ks after the Fermi/GBM trigger. The X-ray counterpart reported by Maselli & De Pasquale (GCN Circ. 16661) is still detected at a count rate of 9.9 (+/-2.5) x 10^-3 cts s^-1. This latest measurement corresponds to a decay slope of 0.8 (+0.5, -0.4): thus we confirm that this source is the afterglow of GRB 140801A. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 16666 SUBJECT: GRB 140801A: GROND Afterglow detection, unbroken decay DATE: 14/08/03 22:14:51 GMT FROM: Alexander Kann at TLS Tautenburg D. A. Kann (TLS Tautenburg), C. Delvaux, and J. Greiner (both MPE Garching) report on behalf of the GROND team: We observed the field of GRB 140801A (Fermi trigger 428612396; Pelassa, GCN #16658) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2 m MPG telescope at ESO La Silla Observatory (Chile). Observations started at 09:43 UT on 2014-08-02, 0.61 days after the GRB trigger. They were performed at an average seeing of 1".5 and at an average airmass of 2.1. Based on images with exposure times of 1584 s in g'r'i'z', we detect the optical afterglow at the MASTER position reported by Gorbovskoy et al. (GCN #16653) at the following AB magnitudes: g' = 22.4 +/- 0.1 mag, r' = 21.9 +/- 0.1 mag, i' = 21.8 +/- 0.1 mag, and z' = 21.2 +/- 0.2 mag. Observations taken a day later show the afterglow to have decayed by about 0.75 magnitudes. The afterglow continues to decay with a slope of ~0.9 in comparison to the magnitudes given by Xu et al. (GCN #16656) and Moskvitin et al. (GCN #16663). The given magnitudes are derived based on calibrating the images against the GROND zeropoints and are not corrected for the Galactic foreground extinction corresponding to a reddening of E_(B-V) = 0.23 in the direction of the burst (Schlegel et al. 1998). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 16667 SUBJECT: GRB 140801A: AAO optical observations DATE: 14/08/04 01:38:25 GMT FROM: Alexei Pozanenko at IKI, Moscow A. Volnova (IKI), R. Inasaridze (AAO), Molotov (KIAM), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: We observed the field of GRB 140801A (Pelassa, GCN 16658) with AS-32 (0.7m) telescope of Abastumani Observatory starting on Aug. 02 (UT) 21:54:52. We obtained several unfiltered frames under of 60 s under average FWHM of 2.0 arcsec. The optical afterglow (Gorbovskoy et al., GCN 16653; Xu et al., GCN 16656, Masi, GCN 16659) is well detected on the stacked image. Details of a photometry of the GRB 140801A are following: date UT start t-T0 Filter Exp. OT err (mid, days) (s) 2014-08-02 21:54:52 1.14962 None 26*60 22.13 0.18 The photometry is based on the USNO-B1 star ((J2000) 02:56:16.58 +30:57:02.1 assuming R = 16.06) suggested by Moskvitin et al., (GCN 16663). Our photometry does not contradict un-broken decay of a light curve of GRB 140801A (Kann et al., GCN 16666).