//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11894 SUBJECT: GRB 110407A: Swift detection of a burst DATE: 11/04/07 14:18:56 GMT FROM: Scott Barthelmy at NASA/GSFC C. W. Wolf (PSU), S. D. Barthelmy (GSFC), A. P. Beardmore (U Leicester), S. Campana (INAF-OAB), V. D'Elia (ASDC), P. A. Evans (U Leicester), N. Gehrels (NASA/GSFC), J. M. Gelbord (PSU), B. Gendre (ASDC), C. Guidorzi (U Ferrara), S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU), H. A. Krimm (CRESST/GSFC/USRA), O. M. Littlejohns (U Leicester), V. Mangano (INAF-IASFPA), P. T. O'Brien (U Leicester), J. P. Osborne (U Leicester), C. Pagani (U Leicester), K. L. Page (U Leicester), P. Romano (INAF-IASFPA), M. H. Siegel (PSU), E. Sonbas (GSFC/USRA/Adiyaman Univ.), R. L. C. Starling (U Leicester), G. Stratta (ASDC), M. C. Stroh (PSU), C. A. Swenson (PSU), G. Tagliaferri (INAF-OAB), E. Troja (NASA/GSFC/ORAU) and T. N. Ukwatta (MSU) report on behalf of the Swift Team: At 14:06:41 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 110407A (trigger=450884). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 185.997, +15.718 which is RA(J2000) = 12h 23m 59s Dec(J2000) = +15d 43' 04" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). Even for an image trigger, the BAT lightcurve shows a smooth peak about 100 sec long with a peak roughly at T+20 sec. The XRT began observing the field at 14:09:20.4 UT, 159.3 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 186.0333, +15.7115 which is equivalent to: RA(J2000) = 12h 24m 07.99s Dec(J2000) = +15d 42' 41.3" with an uncertainty of 5.2 arcseconds (radius, 90% containment). This location is 127 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. UVOT took a finding chart exposure of 150 seconds with the White filter starting 167 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 expected extinction corresponding to E(B-V) of 0.03. Burst Advocate for this burst is C. W. Wolf (cwolf AT astro.psu.edu). 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: 11896 SUBJECT: GRB 110407A: Prompt enhanced Swift-XRT position DATE: 11/04/07 14:44:46 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 110407A, we find an enhanced XRT position of the afterglow: RA, Dec: 186.0313, 15.7117 which is equivalent to: RA (J2000) = 12 24 7.51 Dec (J2000) = +15 42 42.1 with an uncertainty of 2.1 arc sec (radius, 90% confidence). Analysis of the promptly available data is online at http://www.swift.ac.uk/sper/450884. 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: 11897 SUBJECT: GRB 110407A: MASTER early optical observations DATE: 11/04/07 14:51:40 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V.Yurkov, Yu.Sergienko, D.Varda, I.Kudelina Blagoveschensk Educational State University, Blagoveschensk E. Gorbovskoy, V. Lipunov, V.Kornilov, D.Kuvshinov, A.Belinski, N.Tyurina, N.Shatskiy, P.Balanutsa, V.V.Chazov, P.V.Kortunov, A.Kuznetsov, D.Zimnukhov, M. Kornilov, A.Kuznetsov, D.Zimnukhov, M. Kornilov, A.Sankovich Sternberg Astronomical Institute, Moscow State University A. Tlatov, A.V. Parhomenko, D. Dormidontov Kislovodsk Solar Station of the Pulkovo Observatory V.Krushinski, I.Zalozhnich, T.Kopytova, A. Popov Ural State University, Kourovka K.Ivanov, S.Yazev, N.M.Budnev, E.Konstantinov, V.Lenok, O.Gres, O.Chuvalaev, V.A.Poleshchuk Irkutsk State University MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in Blagoveschensk was pointed to the GRB110407 25 sec s after notice time and 107 sec after GRB time at 2011-04-07 14:08:28.65 UT. On our first (20s exposure) set we haven`t found optical transient within SWIFT-BAT error-box. The 5-sigma unfiltred upper limit has been about 17.8 mag MASTER II robotic telescope in Tunka also pointed on GRB110407 at same time in two polarizations. Unfortunately during this moment there was a strong clouds in the given direction and a upper limit very small. The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11898 SUBJECT: GRB 110407A : Xinglong TNT upper limit DATE: 11/04/07 15:18:55 GMT FROM: L.P. Xin at NAOC L.P. Xin, Y. Urata, Z. X. Ling, Y.L. Qiu, J.Y. Wei, J. Wang, J.S. Deng, C. Wu, X. H. Han on behalf of EAFON report: We began to observe GRB110407A ( Wolf et al., GCN 11894) with Xinglong TNT telescope at 14:28:05(UT), 21.5min after the burst, under the dusty and cloudy wheather. A series of R-band images were obtained. No any new source was found within the errorbox of X-ray counterpart ( Wolf et al., GCN 11894 ), down to 3 sigma upper limit of R ~ 18.3 mag, derived from USNO B1.0 R2 magnitude, at the mean time of 26 min after the burst This message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11899 SUBJECT: GRB 110407A : Lulin optical afterglow detection DATE: 11/04/07 16:48:39 GMT FROM: Kuiyun Huang at ASIAA GRB 110407A : Lulin optical afterglow detection C.J. Chuang, C.S. Lin, Y. Urata (NCU) and K.Y. Huang (ASIAA) on behalf of the EAFON cooperation: The 1-m telescope at Lulin Observatory started to observe GRB110407A (Wolf et al. GCN 11849) at 21 minutes after the BAT trigger. A series of our r'-band observations found a fading optical source in the XRT error region reported by Evans (GCN 11896). The position of the optical afterglow candidate is RA(J200) = 12:24:07.534 Dec(J200) = +15:42:46.63 with 1" error. We estimated the brightness of the optical transient against with several SDSS stars. Time (sec) mag(AB) error 1438 20.9 0.1 4758 22.7 0.3 This message may be cited //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11902 SUBJECT: GRB 110407A: Swift-BAT refined analysis DATE: 11/04/07 23:10:05 GMT FROM: Scott Barthelmy at NASA/GSFC T. N. Ukwatta (MSU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), M. Stamatikos (OSU), J. Tueller (GSFC), C. W. Wolf (PSU) (i.e. the Swift-BAT team): Using the data set from T-239 to T+800 sec from recent telemetry downlinks, we report further analysis of BAT GRB 110407A (trigger #450884) (Wolf, et al., GCN Circ. 11894). The BAT ground-calculated position is RA, Dec = 186.022, 15.726 deg, which is RA(J2000) = 12h 24m 05.3s Dec(J2000) = +15d 43' 33.2" with an uncertainty of 1.5 arcmin, (radius, sys+stat, 90% containment). The partial coding was 77%. The mask-weighted light curve shows several overlapping peaks starting at ~T-10 sec, peaking at ~T+15 sec, and ending around T+275 sec. T90 (15-350 keV) is 145 +- 15 sec (estimated error including systematics). The time-averaged spectrum from T-2.9 to T+158.8 sec is best fit by a power law with an exponential cutoff. This fit gives a photon index 0.73 +- 0.64, and Epeak of 57.9 +- 15.1 keV (chi squared 46.5 for 56 d.o.f.). For this model the total fluence in the 15-150 keV band is 1.7 +- 0.2 x 10^-6 erg/cm2 and the 1-sec peak flux measured from T+27.64 sec in the 15-150 keV band is 0.5 +- 0.1 ph/cm2/sec. A fit to a simple power law gives a photon index of 1.73 +- 0.12 (chi squared 55.6 for 57 d.o.f.). 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/450884/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11903 SUBJECT: GRB 110407A: Enhanced Swift-XRT position DATE: 11/04/07 23:12:56 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 2767 s of XRT Photon Counting mode data and 6 UVOT images for GRB 110407A, 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 = 186.03111, +15.71170 which is equivalent to: RA (J2000): 12h 24m 7.47s Dec (J2000): +15d 42' 42.1" with an uncertainty of 1.7 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: 11904 SUBJECT: GRB 110407A: NOT optical observations DATE: 11/04/08 01:20:18 GMT FROM: Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst Daniele Malesani (DARK/NBI), Paul Vreeswijk (Univ. Iceland), Dong Xu (WIS), Johan Fynbo (DARK/NBI), Pall Jakobsson (Univ. Iceland), Ingvar Svardh (NOT), and Martin Nielsen (NOT), report on behalf of a larger collaboration: We observed the field of GRB 110407A (Wolf et al., GCN 11895) with the Nordic Optical Telescope equipped with MOSCA. Observations were carried out in the R band, with a seeing of ~1.6", for a total observation time of 50 minutes. The mean time of the observation was Apr 7.943 UT (8.52 hr after the GRB). At the position of the optical and X-ray transient (Chuang et al., GCNs 11899, 11901; Evans et al., GCN 11903), we detect a source close to the detection limit. Its magnitude is R = 23.2 +- 0.20 (Vega) based on calibration against the SDSS r band. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11905 SUBJECT: GRB 110407A: MITSuME Okayama and Ishigakijima Optical upper limits DATE: 11/04/08 02:55:55 GMT FROM: Daisuke Kuroda at OAO/NAOJ D. Kuroda, (OAO, NAOJ), H. Hanayama (IAO, NAOJ), K. Yanagisawa, Y. Shimizu, H. Toda (OAO, NAOJ), T. Miyaji J. Watanabe, (IAO, NAOJ), S.Nagayama (NAOJ), M. Yoshida (Hiroshima), K. Ohta (Kyoto) and N. Kawai(Tokyo Tech) report on behalf of the MITSuME collaboration: We observed the field of GRB 110407A (Wolf et al., GCN 11894) with the optical three color (g', Rc and Ic) CCD camera attached to the MITSuME 50cm telescope of Okayama Astrophysical Observatory and the Murikabushi 1m telescope of Ishigakijima Astronomical Observatory. We did not find any new point source within the enhanced XRT error circle (Evans et al., GCNC 11903) in all the three bands. We could not detect the previously reported afterglow (Chuang et al., GCN 11899). Three sigma upper limits of the OT are listed below. We used SDSS catalog for flux calibration. Okayama Astrophysical Observatory: The observation started on 2011-04-07 14:08:27, (1.8 min after the burst). T0+[day] MID-UT T-EXP[sec] g' Rc Ic ------------------------------------------------------ 0.00472 14:13:28 540.0 >19.3 >19.1 >18.2 0.07701 15:57:35 6840.0 >20.3 >20.2 >19.4 ------------------------------------------------------ T0+ : Elapsed time after the burst [day] T-EXP: Total Exposure time [sec] Ishigakijima Astronomical Observatory: The observation started on2011-04-07 15:51:28 UT, (1.7 h after the burst). T0+[day] MID-UT T-EXP[sec] g' Rc Ic ------------------------------------------------------ 0.12244 17:02:59 1080.0 >20.9 >20.7 >19.7 ------------------------------------------------------ T0+ : Elapsed time after the burst [day] T-EXP: Total Exposure time [sec] //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11906 SUBJECT: GRB 110407A: GROND Detection of the Optical Afterglow DATE: 11/04/08 08:10:39 GMT FROM: Patricia Schady at MPE/Swift D. A. Kann (TLS Tautenburg), P. Schady and J. Greiner (both MPE Garching) report on behalf of the GROND team: We observed the field of GRB 110407A (Swift trigger 450884; Wolf et al., GCN #11894) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2 m MPI/ESO telescope at La Silla Observatory (Chile). Observations started at 00:50 UT on April 8, 11 hours after the GRB trigger, and continued until ~03:30 UT. They were performed at a seeing of 1.5-2.5" and at an average airmass of 1.5. We detect a point source within the 1.7 arcsec enhanced Swift-XRT error circle (Evans et al., GCN #11903), consistent with the optical afterglow detection reported by Chuang et al. (GCN #11901) and Malesani et al. (GCN #11904) in the g'r'i'z' bands. In an exposure of 102 mins at a mid-observing time of 02:31 UT (12.5 hours after the BAT trigger), we estimate a preliminary r'-band magnitude (in the AB system) of 23.9+/-0.1. The r'-band magnitude is calibrated against SDSS field stars and has not been corrected for the expected Galactic foreground extinction corresponding to a reddening of E_(B-V)=0.03 mag in the direction of the burst (Schlegel et al. 1998). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11907 SUBJECT: GRB110407A: UVOT Upper Limits DATE: 11/04/08 12:05:39 GMT FROM: Samantha Oates at MSSL S. R. Oates (MSSL-UCL) & C. W. Wolf (PSU) report on behalf of the Swift-UVOT team The Swift/UVOT began settled observations of the field of GRB 110407A 168s after the trigger (Wolf et al., GCN Circ. 11895). We do not detect a source at the position of the X-ray (Evans et al., GCN Circ. 11896, 11903) or optical afterglow reported by Lulin (Chuang et al, GCN Circ. 11899, 11901), NOT (Malesani et al., GCN Circ. 11904) and GROND (Kann et al, GCN Circ. 11906). Preliminary magnitudes using the UVOT photometric system (Poole et al. 2008,MNRAS, 383, 627) for the finding chart (FC) and summed exposures at the location of the optical afterglow are: Filter T_start(s) T_stop(s) Exp(s) Mag/3sigUL ##################################################### wh (FC) 168 317 147 >20.82 wh 607 6514 580 >21.59 u (FC) 327 577 246 >20.11 u 732 6104 413 >20.41 v 658 6873 382 >19.74 b 583 6309 432 >20.75 uvw1 708 5899 413 >20.34 uvm2 5493 5693 197 >19.75 uvw2 808 6719 413 >20.68 ##################################################### The values quoted above are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.03 in the direction of the burst (Schlegel et al. 1998). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11908 SUBJECT: GRB 110407A: MASTER optical observations DATE: 11/04/08 15:16:15 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V.Yurkov, Yu.Sergienko, D.Varda, I.Kudelina Blagoveschensk Educational State University, Blagoveschensk E. Gorbovskoy, V. Lipunov, V.Kornilov, D.Kuvshinov, A.Belinski, N.Tyurina, N.Shatskiy, P.Balanutsa, V.V.Chazov, P.V.Kortunov, A.Kuznetsov, D.Zimnukhov, M. Kornilov, A.Kuznetsov, D.Zimnukhov, M. Kornilov, A.Sankovich Sternberg Astronomical Institute, Moscow State University A. Tlatov, A.V. Parhomenko, D. Dormidontov Kislovodsk Solar Station of the Pulkovo Observatory V.Krushinski, I.Zalozhnich, T.Kopytova, A. Popov Ural State University, Kourovka K.Ivanov, S.Yazev, N.M.Budnev, E.Konstantinov, V.Lenok, O.Gres, O.Chuvalaev, V.A.Poleshchuk Irkutsk State University MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in Blagoveschensk was pointed to the GRB110407 25 sec after notice time and 107 sec after GRB time at 2011-04-07 14:08:28.65 UT. On our first (20s exposure) set we haven`t found optical transient within SWIFT-BAT error-box up to 17.8 mag (5 sigma unfiltered)(Yurkov et al., GCN Circ No 11897). The results of the follow observations are: T_mean-Tgrb [s] Tstart exptime 3 sigma-mlimit Coadd 209 14:08:28 200 19.7 5 1143 14:14:03 1220 21.3 10 2341 14:14:03 3380 22.0 22 3640 14:14:03 5720 22.5 35 There is no OT at the Lulin position (Chuang et al., GCN Circ 11899) The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11912 SUBJECT: GRB 110407A: SMARTS optical limit DATE: 11/04/08 23:35:14 GMT FROM: Bethany Cobb at GWU B. E. Cobb (GWU), reports: Using the ANDICAM instrument on the SMARTS 1.3m telescope at CTIO, we obtained optical imaging of the error region of GRB 110407A (GCN 11894, Wolf et al.) with a mid-exposure time of 2011-04-08 02:12 UT (~12.1 hrs post-burst). The total summed exposure time amounted to 36 minutes in I. No optical sources is detected at the position of the optical afterglow of GRB 110407A (GCN 11901, Chuang et al.; GCN 11904, Malesani et al.; GCN 11906, Kann et al.) to a limit of I > 20.3. Optical photometry is calibrated against Landolt standard stars. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11914 SUBJECT: GRB 110407A:VLF observations on 20.27kHz DATE: 11/04/09 16:17:17 GMT FROM: Matus Kocka at AI AS CR, Ondrejov Matus Kocka (AI AS CR), Rudolf Slosiar (Rudy BASE Observatory Bojnice), Vladimir Karlovsky (Observatory Hlohovec), Richard Marko (AI AS CR), Jan Karlovsky (Observatory Hlohovec), Rene Hudec (AI AS CR) We observed the ionospheric perturbation on Apr. 7th which started at 14:06:21 UT from 3 different VLF receivers, so called SID monitors (Sudden Ionospheric Disturbance) on ICV channel 20.27kHz. This event is with a high probability GRB 110407A (Wolf et al., GCN 11895). The detectors are located in Bojnice (Slovakia), Hlohovec (Slovakia) and Brno (Czech Republic). Those places are so far apart that we can rule out a possibility of a local disturbance. The plot from all three SID-monitors is here: http://zeus.asu.cas.cz/~koci/grb110407a/GRB110407A_vlf.png Further analysis is ongoing. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 11916 SUBJECT: GRB 110407A: Swift-XRT refined Analysis DATE: 11/04/11 03:58:19 GMT FROM: Chris Wolf at PSU C. W. Wolf (PSU) reports on behalf of the Swift-XRT team: We have analysed 26 ks of XRT data for GRB 110407A (Wolf et al. GCN Circ. 11894), from 147 s to 272.1 ks after the BAT trigger. The data comprise 593 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 Evans et al. (GCN. Circ 11896). After initial flaring (T>0.9 ks), the light curve can be modeled by a broken power-law model, with an initial decay index of alpha1=2.19 (+0.12, -0.11). A break occurs at T+13.6 ks followed by a plateau phase with a decay index of alpha2 = 0.4 (+0.5, -0.7). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.80 (+/-0.05). The best-fitting absorption column is 1.00 (+/-0.13) x 10^21 cm^-2, in excess of the Galactic value of 2.0 x 10^20 cm^-2 (Kalberla et al. 2005). The PC mode spectrum has a photon index of 1.87 (+0.21, -0.11) and a best-fitting absorption column of 8.4 (+5.1, -2.7) x 10^20 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 4.2 x 10^-11 (5.0 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 8.4 (+5.1, -2.7) x 10^20 cm^-2 Galactic foreground: 2.0 x 10^20 cm^-2 Excess significance: 5.2 sigma Photon index: 1.87 (+0.21, -0.11) The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00450884. This circular is an official product of the Swift-XRT team.