//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 10376 SUBJECT: GRB 100206A: Swift detection of a short hard burst DATE: 10/02/06 13:44:17 GMT FROM: David Palmer at LANL H. A. Krimm (CRESST/GSFC/USRA), W. H. Baumgartner (GSFC/UMBC), P. A. Evans (U Leicester), N. Gehrels (NASA/GSFC), C. Guidorzi (U Ferrara), S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU), V. Mangano (INAF-IASFPA), F. E. Marshall (NASA/GSFC), P. T. O'Brien (U Leicester), K. L. Page (U Leicester), D. M. Palmer (LANL), J. L. Racusin (NASA/GSFC), M. H. Siegel (PSU), M. A. Stark (PSU), R. L. C. Starling (U Leicester), E. Troja (NASA/GSFC/ORAU), T. N. Ukwatta (GSFC/GWU) and L. Vetere (PSU) report on behalf of the Swift Team: At 13:30:05 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 100206A (trigger=411412). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 47.177, +13.168 which is RA(J2000) = 03h 08m 42s Dec(J2000) = +13d 10' 04" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single strong peak with a duration of about .3 sec. The peak count rate was ~14766 counts/sec (15-350 keV), at ~0 sec after the trigger. The XRT began observing the field at 13:31:20.0 UT, 74.6 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source with an enhanced position: RA, Dec 47.1617, 13.1579 which is equivalent to: RA(J2000) = 03h 08m 38.81s Dec(J2000) = +13d 09' 28.4" with an uncertainty of 3.8 arcseconds (radius, 90% containment). This location is 64 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 1.32e+21 cm^-2 (Kalberla et al. 2005). 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 expected extinction corresponding to E(B-V) of 0.38. Burst Advocate for this burst is H. A. Krimm (krimm 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: 10377 SUBJECT: GRB 100206A: Pre-explosion imaging and host candidate DATE: 10/02/06 14:29:52 GMT FROM: Daniel Perley at U.C. Berkeley A. A. Miller, D. A. Perley, J. S. Bloom, S. B. Cenko (UC Berkeley), and P. E. Nugent (LBNL) report: We co-added 78 archival images from the DeepSky* project at Palomar Observatory covering the field of GRB 100206A (Krimm et al., GCN 10376). The images were obtained between 2004-2008 from the Palomar-Quest Consortium at the Oschin Schmidt telescope. The limiting magnitude of the stack is approximately R ~ 23 mag. In the combined image we detect a faint (R = 21.7 +/- 0.3 mag relative to nearby USNO catalog stars) extended source, slightly outside the current XRT error circle to its northeast. The approximate (+/- 1") coordinates of the source are: RA = 03:08:39.10, dec = +13:09:29.3 (J2000) We suggest this as a potential host candidate of the short-hard burst and encourage spectroscopic follow-up. * http://supernova.lbl.gov/~nugent/deepsky.html //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 10378 SUBJECT: GRB 100206A: Enhanced Swift-XRT position DATE: 10/02/06 17:30:38 GMT FROM: Phil Evans at U of Leicester M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team. Using 1262 s of XRT Photon Counting mode data and 1 UVOT images for GRB 100206A, 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 = 47.16225, +13.15708 which is equivalent to: RA (J2000): 03h 08m 38.94s Dec (J2000): +13d 09' 25.5" with an uncertainty of 3.2 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: 10379 SUBJECT: GRB 100206A: Swift-BAT refined analysis DATE: 10/02/06 17:34:23 GMT FROM: Scott Barthelmy at NASA/GSFC T. Sakamoto (GSFC/UMBC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. N. Ukwatta (GWU) (i.e. the Swift-BAT team): Using the data set from T-240 to T+302 sec from the recent telemetry downlink, we report further analysis of BAT GRB 100206A (trigger #411412) (Krimm, et al., GCN Circ. 10376). The BAT ground-calculated position is RA, Dec = 47.168, 13.175 deg which is RA(J2000) = 03h 08m 40.3s Dec(J2000) = +13d 10' 30.3" with an uncertainty of 1.5 arcmin, (radius, sys+stat, 90% containment). The partial coding was 51%. The mask-weighted light curves a single spike starting at ~T+0.0 and ending at ~T+0.2 sec. T90 (15-350 keV) is 0.12 +- 0.03 sec (estimated error including systematics). The time-averaged spectrum from T-0.008 to T+0.124 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 0.63 +- 0.17. The fluence in the 15-150 keV band is 1.4 +- 0.2 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T-0.44 sec in the 15-150 keV band is 1.4 +- 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/411412/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 10380 SUBJECT: GRB 100206A: Optical limit DATE: 10/02/06 18:34:33 GMT FROM: Dipankar Bhattacharya at IUCAA D. Bhattacharya, Vijay Mohan, A.N. Ramaprakash, Chaitanya Rajarshi (IUCAA) and Kuntal Misra (STScI)report: We imaged the field of GRB100206A (Krimm et al. GCN 10376, Goad et al GCN 10378) using the 2-m telescope of the IUCAA Girawali Observatory. Four 15-min exposures in R-band were taken on 06 Feb 2010 starting at 15:46 UT. The stacked 1 hour exposure shows no optical transient to a limiting magnitude of R ~22. The extended source reported by Miller et al (GCN 10377) is however clearly detected. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 10381 SUBJECT: GRB 100206A: Fermi GBM observation DATE: 10/02/06 19:02:46 GMT FROM: Andreas von Kienlin at MPE A. von Kienlin (MPE) reports on behalf of the Fermi GBM Team: "At 13:30:05.39 UT on 06 February 2010, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 100206A (trigger 287155807 / 100206563) which was also detected by the SWIFT-BAT (Krimm et al. 2008, GCN 10376). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight is 44.7 degrees. The Fermi Observatory executed a maneuver following this trigger and tracked the burst location for the next 5 hours, subject to Earth-angle constraints. The GBM light curve shows a single bright peak with a duration (T90) of about 0.13 +/- 0.05 s (8-1000 keV). The time-averaged spectrum from T0-0.019 s to T0+0.109 s is best fit by a power law function with an exponential high energy cutoff. The power law index is -0.18 (+/-0.13) and the cutoff energy, parameterized as Epeak, is 506 (+68/-53) keV (Castor C statistic of 569 for 479 d.o.f.) The event fluence (8-1000 keV) in this time interval is (9.3 +/- 0.4)E-07 erg/cm^2. The 0.016-sec peak photon flux measured starting from T0-0.003 s in the 8-1000 keV band is 31 +/- 2 ph/s/cm^2. A Band function fits the spectrum equally well (Castor C statistic of 565 for 478 d.o.f.) with Epeak= 439 (+73/-60) keV, alpha = -0.09 (+0.17/-0.15)and beta = -2.35 (+0.24/-0.43) . The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 10382 SUBJECT: GRB 100206A: Swift-XRT refined analysis DATE: 10/02/06 19:06:13 GMT FROM: Phil Evans at U of Leicester P.A. Evans and H. A. Krimm (CRESST/GSFC/USRA) report on behalf of the Swift-XRT team: We have analysed 1.3 ks of XRT data for GRB 100206A (Krimm et al. GCN Circ. 10376), from 82 s to 1.3 ks after the BAT trigger. The data are entirely in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Goad et al. (GCN. Circ 10378). The light curve can be modelled with a power-law decay with a decay index of alpha=1.9 (+0.9/-0.7). A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.0 (+1.2, -0.9). The best-fitting absorption column is 3.5 (+5.3, -0.0) x 10^21 cm^-2, in excess of the Galactic value of 1.3 x 10^21 cm^-2 (Kalberla et al. 2005). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 4.6 x 10^-11 (7.4 x 10^-11) erg cm^-2 count^-1. If the light curve continues to decay with a power-law decay index of 1.9, the count rate at T+24 hours will be 1.9 x 10^-7 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.9 x 10^-17 (4.7 x 10^-17) erg cm^-2 s^-1. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00411412. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 10384 SUBJECT: GRB 100206A: optical observations from Southern Spain DATE: 10/02/06 21:34:06 GMT FROM: Alberto Castro-Tirado at Inst.de Astro. de Andalucia S. Guziy, F. J. Aceituno and A. J. Castro-Tirado (IAA-CSIC Granada), on behalf of a larger collaboration, report: “Following the detection of the short-duration gamma-ray burst GRB 100206A by Swift/BAT (Krimm et al. GCN Circ. 10376), we have conducted follow-up observations with the 0.6m TELMA robotic telescope (+ clear filter) at the BOOTES-2 station in Málaga and with the 1.5m OSN telescope (+ I-band filter) at Observatorio de Sierra Nevada in Granada. No optical afterglow is detected within the Swift/XRT error box (Goad et al., GCN Circ. 10378). An upper limit of I = 21 is derived from a combined 9 x 150-s I-band image obtained starting at 18:40 UT (5.2 hr postburst), consistent with the null result reported by Bhattacharya et al. (GCN Circ. 10380). The candidate host galaxy reported by Miller et al. (GCN Circ. 10377) is also detected at the edge of the error box.” This message can be quoted. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 10385 SUBJECT: GRB 100206A, RIMOTS optical upper limits DATE: 10/02/06 22:03:16 GMT FROM: Kazuhiro Noda at Miyazaki U K.Noda, E.Sonoda, H.hayasi, K.Kono, N.Ohmori, A.Daikyuji, Y.Nisioka, M.Yamauchi (University of Miyazaki) We have observed the field covering the error circle of GRB GRB090206A (Swift trigger 411412, GCN 10376, Krimm et al.) with the unfiltered CCD camera on the 30-cm telescope at University of Miyazaki. The observation was started 13:31:14 UT, about 1 min after the Swift trigger time. We have compared our data of 30 sec exposures with the USNO-A2.0 catalog, There is no new source at the reported position. the upper limits are as follows: -------------------------------------------------------------- Start(UT) End(UT) Num. of frames Limit (mag.) -------------------------------------------------------------- 13:31:14 13:31:44 1 14.1 13:31:14 14:26:55 29 17.4 --------------------------------------------------------------- //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 10386 SUBJECT: GRB 100206A: WHT candidate afterglow DATE: 10/02/06 23:56:02 GMT FROM: Andrew Levan at U.of Leicester A.J. Levan (U. Warwick), N.R. Tanvir, K. Wiersema (U. Leicester) M. Niederste-Ostholt (Cambridge), D. Malesani, G. Leloudas (DARK/NBI) D. Xu (WIS & DARK/NBI) report for a larger collaboration: "We observed the localization of GRB 100206A (Krimm et al. GCN 10376) with the WHT beginning at 20:33 UT, approximately 7 hours after the burst. Observations were obtained in the i and z bands with exposures of 2000 and 2400s respectively. Inside the refined XRT error circle (Goad et al. GCN 10378), we detect a faint source in both the i and z-bands. The location of the source is: RA(J2000) = 03:08:38.99 DEC(J2000) = 13:09:22.7 With an uncertainty of approximately 0.5" in each axis. We consider this to be a candidate afterglow of GRB 100206A, however cannot currently place any constraints on variability of the source. Further observations are planned." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 10387 SUBJECT: GRB 100206A: NOT NIR observations DATE: 10/02/06 23:56:28 GMT FROM: Giorgos Leloudas at Dark Cosmology Centre G. Leloudas (DARK/NBI), D. Xu (WIS and DARK/NBI), D. Malesani (DARK/ NBI), A. J. Levan (U. Warwick), P. Jakobsson (Univ. Iceland), A. A. Djupvik (NOT), report, on behalf of a larger collaboration: We observed the field of GRB 100206A (Krimm et al., GCN 10376) with the NOT equipped with NOTCam. Observations were carried out in the Ks-filter (6x9x60 s) starting at 20h24 UT, i.e. 6.9 hr after the GRB. Inside the enhanced XRT position (Goad et al., GCN 10378) we do not detect any object down to a limiting magnitude > 19.7 (based on the nearby 2MASS star 03083760+1308461). The extended object reported by Miller et al. (GCN 10377) is clearly detected at Ks ~ 16.4. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 10388 SUBJECT: GRB100206: MITSuME optical upper limits DATE: 10/02/07 02:15:59 GMT FROM: Daisuke Kuroda at OAO/NAOJ D. Kuroda, K. Yanagisawa, Y. Shimizu, S. Nagayama, H. Toda (OAO, NAOJ), M. Yoshida (Hiroshima) and N. Kawai (Tokyo Tech) report on behalf of the MITSuME collaboration: We observed the field of GRB 100206A (Krimm et al. GCN 10376) with the optical three color (g', Rc and Ic) CCD camera attached to the MITSuME 50cm telescope of Okayama Astrophysical Observatory. The observation started on 2010-02-06 13:31:10 UT (65s after the burst). We did not find any new point source in the XRT error circle in all the three bands. Three sigma upper limits of the OT are listed below. We used GSC2.3 catalog for flux calibration. PDAY MID-UT T-EXP g' Rc Ic --------------------------------------------------- 0.00422 13:36:10 480.0 >19.0 >19.0 >17.9 0.02166 14:01:17 2940.0 >19.8 >19.8 >18.7 --------------------------------------------------- //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 10389 SUBJECT: GRB 100206A - Keck/LRIS Spectroscopy DATE: 10/02/07 06:49:28 GMT FROM: S. Bradley Cenko at Caltech S. B. Cenko, J. S. Bloom, D. A. Perley, B. E. Cobb, A. N. Morgan, and A. A. Miller, Maryam Modjaz (UC Berkeley) and B. James (DARK) report on behalf of a larger collaboration: We have obtained spectra of the likely host galaxy (Miller et al., GCN 10377) and afterglow (Levan et al., GCN 10386) of the short-hard GRB100206A (Krimm et al, GCN 10376) with the Low Resolution Imaging Spectrometer mounted on the 10-m Keck I telescope. Observations began at 06:17 UT on 7 February (~ 16.8 hours after the burst) and cover the wavelength range from approximately 3500 - 10000 A. At the location of the candidate host galaxy, we detect a strongly red continuum consistent with the published photometry (Leloudas et al., GCN 10387). We detect strong, clearly resolved emission lines from H-alpha and [NII] at a redshift of z = 0.41. No other obvious lines are visible over spectral range in our preliminary reduction. The lack of H-beta, coupled with the red spectrum and colors, suggest a relatively dusty environment. At this redshift, the projected offset of ~ 6.8" from the candidate afterglow corresponds to a distance of ~ 35 kpc. No obvious trace is visible at the location of the afterglow. Observations and reduction are ongoing. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 10390 SUBJECT: GRB 100206A: PAIRITEL Photometry of Host Candidate DATE: 10/02/07 11:00:55 GMT FROM: Adam Morgan at U.C. Berkeley A. N. Morgan, B. E. Cobb, J. S. Bloom, S. B. Cenko, D. A. Perley, A. A. Miller, M. Modjaz, C. R. Klein (UC Berkeley), report: We have imaged the field of the short-hard GRB 100206A (Krimm et al., GCN 10376) with the 1.3m PAIRITEL located at Mt. Hopkins, Arizona. Observations began at 2010-02-07 02:37:50 UT (~13.1 hours after the burst). The potential host galaxy (Miller et al., GCN 10377) is clearly detected in mosaics taken simultaneously in the J, H, and Ks filters (effective exposure time of 2293 seconds). The preliminary photometry yields: exp(s) filt mag ============================== 2293 J 18.35 +/- 0.07 2293 H 17.55 +/- 0.08 2293 Ks 16.56 +/- 0.08 ============================== A preliminary estimate of the metallicity from the Halpha and [N II] line ratios suggest a super-solar metallicity (~1.5 solar metallicity, using Asplund 2009 for Solar oxygen abundance). At a redshift of z = 0.41 (Cenko et al., GCN 10389), and assuming a Lambda-CDM cosmology with H_0=74 km/s/Mpc, Omega_M=0.27 and Omega_Lambda=0.73, we calculate the distance modulus to be 41.65 mag, which implies a rest-frame H-band magnitude of about -25 mag. This extreme luminosity, coupled with what appears to be strong optical reddening (Cenko et al., GCN 10389) suggests that this galaxy is a luminous infrared galaxy (LIRG/ULIRG). While the physical connection to GRB 100206A has not been definitively established, the probability of a chance coincidence of such a galaxy with a SHB is low, providing an a posterori argument for a physical connection. All magnitudes given in the Vega system, calibrated to 2MASS. No correction for Galactic extinction has been made to the above reported values. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 10391 SUBJECT: GRB 100206A: MASTER-Net optical alert observations DATE: 10/02/07 13:24:10 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V.Yurkov, S.Sergienko Blagoveschensk Educational State University, Blagoveschensk E. Gorbovskoy, V. Lipunov, V.Kornilov, A.Belinski, N.Shatskiy, N.Tyurina, D.Kuvshinov, P.Balanutsa, V.V.Chazov, P.V.Kortunov, A.Kuznetsov, D.Zemnukhov, M. Kornilov Sternberg Astronomical Institute, Moscow State University A. Tlatov, A.V. Parhomenko, D. Dormidontov Kislovodsk Solar Station of the Pulkovo Observatory V.Krushinski, I.Zalozhnih, T.Kopytova, A. Popov Ural State University, Kourovka K.Ivanov, S.Yazev, N.M.Budnev, E.Konstantinov, V.Lenok Irkutsk State University MASTER robotic telescope (MASTER-Net: http://observ.pereplet.ru, 200 mm, FOV=8 square degrees (testing mode)) and Very Wide Field Camera (D=50 mm, 1000 square degrees, 11 Mpx, 36" per pix, mounted on telescope) located at Blagoveschensk was responted to the GRB 100206A (Swift BAT alert, TRIGGER_NUM: 411412, Krimm et al, GCN CIRC 10376) 73 sec after first Notice time and 90 s after the GRB time. Unfortunatelly, the main telescope camera was not operating due to technical problem at this time. We have a number images with 5 s exposition from Very Wide Field Camera. The image limit from Very Wide Filed Camera ~11.5. trees) is available at http://observ.pereplet.ru/images/GRB100206A/grb100206A.png . There is no OT brighter 11.5. The message may be cited. mailto: lipunov@sai.msu.ru //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 10392 SUBJECT: GRB 100206A: YNAO-GMG observations DATE: 10/02/07 13:26:10 GMT FROM: Jirong Mao at INAF-OAB J. Mao (YNAO & INAF-OAB), D. Wang and J. Bai (YNAO) report on behalf of the GMG group: Starting 14h 44m UT, after more than 1 hour of the trigger, we observed the field of GRB 100206A (Krimm et al., GCN 10376) with one 2.4-m telescope located at Gao-Mei-Gu (GMG). We did not see the afterglow in the R-band image with exposure time 20 min. However, the nearby galaxy(Miller et al. GCN 10377) were clearly detected, the magnitude is about R ~ 21.5 referenced to one USNO star. This message might be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 10394 SUBJECT: GRB 100206A: Swift/UVOT Upper Limits DATE: 10/02/07 17:03:04 GMT FROM: Frank Marshall at GSFC F.E. Marshall (NASA/GSFC) and H.A. Krimm (CRESST/GSFC/USRA) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 100206A 78 s after the BAT trigger (Krimm et al., GCN Circ. 10376). No optical afterglow consistent with the refined XRT position (Goad et al., GCN Circ. 10378) or the candidate optical afterglow position (Levan et al., GCN Circ. 10386) is detected in the initial UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Poole et al. 2008, MNRAS, 383, 627) for the first finding chart (FC) exposures and subsequent exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white_FC 78 228 147 >20.5 u_FC 290 540 246 >20.1 white 78 7046 647 >21.4 v 619 7457 553 >20.1 b 545 13655 1223 >21.2 u 290 12756 1464 >20.5 w1 668 7866 510 >20.7 The values quoted above are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.38 in the direction of the burst (Schlegel et al. 1998). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 10395 SUBJECT: GRB 100206A: Gemini-North observations DATE: 10/02/07 17:13:40 GMT FROM: Edo Berger at Harvard E. Berger, R. Chornock (Harvard), N. Tanvir (U. Leicester), A.J. Levan (U. Warwick), D. Fox, A. Cucchiara (PSU), A. Fruchter and J. Graham (STScI) report on behalf of a larger collaboration: "We observed the field of the short GRB 100206A (GCN #10376) with GMOS on the Gemini-North 8-m telescope starting on 2010 Feb 7.215 (15.7 hours after the burst). Observations were obtained in the i- and z-band filters for a total of 1200 sec in each filter. Inside the refined XRT error circle (GCN #10378) we detect the candidate optical afterglow detected with the WHT (GCN #10386). Within the photometric uncertainties the source does not appear to fade in either filter between the two observation (7 and 15.7 hours) and it is thus unlikely to be the optical afterglow. However, since the source is located within the XRT error circle we consider it to be a potential host galaxy, likely at a higher redshift than the bright galaxy at z=0.41 located just outside the error circle (GCN #10389)." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 10396 SUBJECT: GRB 100206A: GROND upper limits DATE: 10/02/07 17:40:07 GMT FROM: Thomas Kruehler at MPE/MPI A. Nicuesa (Tautenburg Obs.), T. Kruehler (MPE), S. Klose (Tautenburg Obs.) and J. Greiner (MPE Garching) report on behalf of the GROND team: We observed the field of GRB 100206A (Swift trigger #411412; Krimm et al., GCN #10376) 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 LaSilla Observatory (Chile). Observations started on 7 February 2010 at 00:31 UT, 11 hours after the GRB trigger, and were performed at high airmass and poor seeing conditions. In stacked images with a total integration time of 40 minutes in JHK and 50 minutes in g'r'i'z' we do not detect the object reported by Levan et al. (GCN #10386) and Berger et al. (GCN #10395) down to the following limits, all in the AB system: g' > 23.2, r' > 23.4, i' > 22.4, z' > 22.2, J > 21.2 , H > 20.7 and K > 20.0 These upper limits have been obtained using the GROND zeropoints and 2MASS field stars as reference. The nearby object (Miller et al., GCN#10377, Bhattacharya et al., GCN#10380, Guziy et al., GCN#10384, Leloudas et al., GCN#10387, Cenko et al., GCN# 10389, Morgan et al., GCN#10390, Mao et al. #10392) is detected in all seven bands. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 10410 SUBJECT: GRB 100206A: Second epoch Gemini-north observations and afterglow limits DATE: 10/02/13 21:24:47 GMT FROM: Edo Berger at Harvard E. Berger and R. Chornock (Harvard) report on behalf of a larger collaboration: "We obtained a second epoch of i-band imaging of the short GRB 100206A (GCN 10376) with GMOS on the Gemini-North 8-m telescope starting on 2010 Feb 12.28 UT. Digital image subtraction of the new observation relative to our previous i-band epoch from 2010 Feb 7.23 UT (GCN 10395) using the ISIS software package does not reveal any fading sources to a 3-sigma limit of i>24.7 mag within the XRT error circle (GCN 10378), in coincidence with the nearby bright galaxy at z=0.41 (GCN 10389), or in coincidence with the nearby fainter galaxy (GCNs 10386,10395). We therefore place a limit of i>24.7 mag on the brightness of the optical afterglow at 15.7 hours after the burst." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 10455 SUBJECT: GRB 100206A: optical observations in Terskol DATE: 10/02/26 02:58:35 GMT FROM: Alexei Pozanenko at IKI, Moscow M.Andreev, A.Sergeev, N.Parakhin, N.Karpov (Terskol Branch of Institute of Astronomy), Yu. Kuznietsova (Main Astronomical Observatory NASU), V.Petkov (Baksan Neutrino Observatory INR) and A. Pozanenko (IKI) on behalf of larger GRB follow up collaboration report: We observed the field of the Swift GRB 100206A (Krimm et al. GCN 10376) with the Z-600 telescope of Mt.Terskol observatory in R-filter on Feb. 06 starting at (UT) 15:49. We obtained three series under variable weather conditions and improving seeing. The upper limits of point like object in combined images of each series are presented below. The photometry is based on the USNO-B1.0 reference stars 1032-0043920 (assuming R2=15.76) and 1031-0041081 (R2=15.78): T0+ Filter, Exposure, mag. (mid, d) (s) 0.1034 R 10x120 >20.5 0.1235 R 20x120 >20.8 0.1631 R 20x120 >21.4 The nearby galaxy (Miller et al., GCN 10377, Bhattacharya et al., GCN 10380, Guziy et al., GCN 10384, Leloudas et al., GCN 10387, Cenko et al., GCN 10389, Morgan et al., GCN 10390, Mao et al. GCN 10392, Nicuesa et al. GCN 10396) is detected in last series in coordinates (J2000) RA=03 08 39.17 Dec=+13 09 28.7 +/-0.5" and magnitude R=21.3 +/-0.3. No objects is detected in enhanced XRT error circle (Goad et al. GCN 10378). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 10456 SUBJECT: GRB 100206A: optical observations in CrAO DATE: 10/02/26 03:00:50 GMT FROM: Alexei Pozanenko at IKI, Moscow V. Rumyantsev, D. Shakhovkoy (CrAO), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: We observed the field of the Swift GRB 100206A (Krimm et al. GCN 10376) with AZT-11 telescope of CrAO between (UT) Feb. 06 16:09 -- 17:10 under poor seeing of about 6 arcsec. No objects is detected in enhanced XRT error circle (Goad et al. GCN 10378). The upper limit of point like object in a stacked image based on USNO-B1.0 star 1031-0041090 (assuming R2=16.63) is following: T0+ Filter, Exposure, mag. (mid, d) (s) 0.1315 R 20x180 > 21.7