//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9430 SUBJECT: GRB 090529: Swift detection of a burst DATE: 09/05/29 14:40:28 GMT FROM: Scott Barthelmy at NASA/GSFC T. Sakamoto (NASA/UMBC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), D. N. Burrows (PSU), J. R. Cummings (NASA/UMBC), P. A. Evans (U Leicester), O. Godet (U Leicester), C. Gronwall (PSU), C. Guidorzi (U Ferrara), S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU), H. A. Krimm (CRESST/GSFC/USRA), V. Mangano (INAF-IASFPA), J. Mao (INAF-OAB), R. Margutti (Univ Bicocca&OAB), C. B. Markwardt (CRESST/GSFC/UMD), F. E. Marshall (NASA/GSFC), P. T. O'Brien (U Leicester), J. P. Osborne (U Leicester), K. L. Page (U Leicester), D. M. Palmer (LANL), B. Sbarufatti (INAF-IASFPA), M. H. Siegel (PSU) and T. N. Ukwatta (GSFC/GWU) report on behalf of the Swift Team: At 14:12:35 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 090529 (trigger=353540). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 212.474, +24.437 which is RA(J2000) = 14h 09m 54s Dec(J2000) = +24d 26' 13" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve does not show anything but this is typical for an image trigger. The XRT began observing the field at 14:15:52.3 UT, 197.1 seconds after the BAT trigger. Using promptly downlinked data we find a bright, fading, uncatalogued X-ray source located at RA, Dec 212.46882, 24.45889 which is equivalent to: RA(J2000) = 14h 09m 52.52s Dec(J2000) = +24d 27' 32.0" with an uncertainty of 3.7 arcseconds (radius, 90% containment). This location is 80 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. A power-law fit to a spectrum formed from promptly downlinked event data gives a column density in excess of the Galactic value (1.61e+20 cm^-2, Kalberla et al. 2005), with an excess column of 2.9 (+1.72/-1.51) x 10^21 cm^-2 (90% confidence). The initial flux in the 2.5 s image was 1.48e-09 erg cm^-2 s^-1 (0.2-10 keV). UVOT took a finding chart exposure of 150 seconds with the White filter starting 205 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 0.02. Burst Advocate for this burst is T. Sakamoto (Taka.Sakamoto 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: 9431 SUBJECT: GRB 090529: Xinglong TNT optical observation DATE: 09/05/29 15:51:34 GMT FROM: L.P. Xin at NAOC L.P. Xin, W.K. Zheng, Y. Urata, Y.L. Qiu, J.Y. Wei, J. Wang, J.S. Deng and J.Y. Hu on behalf of EAFON report: We have observed GRB 090529 (Sakamoto et al. GCN 9430) with Xinglong TNT telescope from May 29, 14:36:54 (UT), 24.3 min after the burst. After combined 20*20s white band images and preliminary analysis, An new source was found in our combined image within the XRT errorbox. The brightness is estimated to be about R~19.4 mag derived from USNO-B1.0 R2 magnitude, at the mean time of 28 min since the trigger. The observation is still going. This message may be cited. For more information about Xinglong GRBs Follow-up observations, please visit the website: http://www.xinglong-naoc.org/grb/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9432 SUBJECT: GRB 090529: Preliminary Swift/UVOT Upper Limit DATE: 09/05/29 17:12:13 GMT FROM: Stephen Holland at USRA/NASA/GSFC/SSC S. T. Holland (CRESST/GSFC/USRA), F. E. Marshall (NASA/GSFC), P. Schady (MSSL-UCL), and T. Sakamoto (NASA/UMBC) report on the behalf of the Swift UVOT team: The Swift/UVOT took a 150 s exposure of the field of GRB 090529 with its white filter starting 204 s after the BAT trigger (Sakamoto, et al., 2009, GCN Circ. 9430). The preliminary 3-sigma upper limit at the XRT position is white > 20.3. This upper limit has not been corrected for the expected Galactic extinction along the line of sight corresponding to a reddening of E_{B-V} = 0.02 mag (Schlegel, et al., 1998, ApJS, 500, 525). The photometry is on the UVOT photometric system described in Poole et al. (2008, MNRAS, 383, 627). The non-detection in the white filter at 204 s, combined with the observation at 28 minutes of R ~ 19.4 (Xin, et al., 2009, GCN Circ. 9431) implies either that this afterglow is unusually red, or that it has brightened during the first half hour after the BAT trigger. Such a long brightening would be highly unusual (Oates, et al., 2009, MNRAS, 395, 450). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9433 SUBJECT: GRB 090529: Enhanced Swift-XRT position DATE: 09/05/29 19:11:24 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 2467 s of XRT Photon Counting mode data and 3 UVOT images for GRB 090529, 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 = 212.46850, +24.45919 which is equivalent to: RA (J2000): 14h 09m 52.44s Dec (J2000): +24d 27' 33.1" 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, arXiv:0812.3662). This circular was automatically generated, and is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9434 SUBJECT: GRB 090529: Swift-BAT refined analysis DATE: 09/05/29 20:10:34 GMT FROM: Hans Krimm at NASA-GSFC C. B. Markwardt (GSFC/UMD), 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), D. M. Palmer (LANL), A. M. Parsons (GSFC), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. N. Ukwatta (GWU) (i.e. the Swift-BAT team): Using the data set from T-60 to T+243 sec from the recent telemetry downlink, we report further analysis of BAT GRB 090529 (trigger #353540) (Sakamoto, et al., GCN Circ. 9430). The BAT ground-calculated position is RA, Dec = 212.446, 24.450 deg which is RA(J2000) = 14h 09m 47.1s Dec(J2000) = +24d 26' 58.5" with an uncertainty of 2.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 83%. The mask-weighted light curve shows that the burst was in progress when it came into the BAT field of view at ~T-50 sec, following a pre-planned slew. The detectable part of the light curve shows an exponentially falling rate, which some possible superimposed peaks at ~T-45, ~T-25 and ~T-15 sec. The count rate is down to background by T+50 seconds. Given that we did not observe the start of the burst, we can only provide a lower limit to T90: T90 (15-350 keV) is > 100 sec. The time-averaged spectrum from T-49.0 to T+39.3 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.00 +- 0.3. The fluence in the 15-150 keV band is 6.8 +- 1.7 x 10-7 erg/cm2. The 1-sec peak photon flux measured from T-50.0 sec in the 15-150 keV band is 0.4 +- 0.1 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/353540/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9435 SUBJECT: GRB090529: UVOT/Swift detection of a brightening optical afterglow DATE: 09/05/29 22:12:44 GMT FROM: Patricia Schady at MSSL/Swift P. Schady (MSSL-UCL), T. Sakamoto (NASA/UMBC), S. T. Holland (CRESST/GSFC/USRA) and F. E. Marshall (NASA/GSFC) report on behalf of the Swift UVOT team: The Swift/UVOT began settled observations of the field of GRB 090529 206s after the BAT trigger (Sakamoto et al., GCN Circ. 9430) and no new source was detected within the XRT position in the first white finding chart (fc) (Sakamoto et al., GCN Circ. 9430; Holland et al., GCN Circ. 9432). However, a new source is detected within the refined XRT error circle (Osborne et al., GCN Circ. 9433) in a second white finding chart, taken at 883s after the BAT trigger, as well as in a co-added b-band exposure at RA (J2000) 14:09:52.56 = 212.46892 (deg) Dec (J2000) +24:27:32.2 = +24.45892 (deg) with an estimated uncertainty of 0.7 arcsec (radius, 90% confidence, statistical + systematic). This source detection is consistent with the white band detection reported by Xin et al. (GCN Circ. 9431). We note that there is weak evidence that the source could be extended. The magnitudes and 3-sigma upper limits for the observations currently available are as follows: Filter T_start(s) T_stop(s) Exp(s) Mag/3-sigma UL white_fc1 206 355 147 > 21.09 white_fc2 883 1032 147 20.81 +/- 0.22 white 1185 2587 175 21.55 +/- 0.31 v 363 2637 253 > 20.24 b 461 2564 233 20.97 +/- 0.36 b 2716 2824 107 > 20.70 u 436 2691 253 > 20.87 uvw1 412 2667 156 > 20.60 uvm2 387 2661 253 > 20.20 uvw2 510 2594 253 > 20.65 The values quoted above are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.02 in the direction of the burst (Schlegel et al. 1998). The photometry is on the UVOT photometric system described in Poole et al. (2008, MNRAS, 383, 627). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9436 SUBJECT: GRB 090529: TLS Afterglow Observations DATE: 09/05/30 00:12:12 GMT FROM: Alexander Kann at TLS Tautenburg D. A. Kann, U. Laux and B. Stecklum (TLS Tautenburg) report: We observed the optical afterglow (Xin et al., GCN 9431) of the Swift GRB 090529 (Sakamoto et al., GCN 9430) with the 1.34m Schmidt telescope of the Thueringer Landessternwarte Tautenburg, Germany. Observations began at twilight, which, together with the setting moon, caused an elevated sky background. Airmass was low and conditions were excellent until clouds came in during the last Rc image. We obtained 6 x 300 sec dithered images in the Ic band and 3 x 600 sec images in the Rc band. The afterglow is very faintly visible on several Ic frames, clearly visible on the first two Rc frames and hardly visible on the last Rc frame. Using the USNOB1.0 catalog as a reference, we derive the following position (J2000) for the afterglow: RA = 14:09:52.53 Dec. = +24:27:32.77 with an error of 0".5. This position lies 0".7 from the UVOT position (Schady et al., GCN 9435), in full agreement with it. We find several sources of roughly similar magnitude within 10" of the afterglow. These may slightly affect the photometry. To calibrate, we use the isolated star with USNO catalog # 1144-0210566 at position RA = 14:09:47.50 Dec. = +24:27:44.5 which has R2 = 18.32 mag and I = 17.54 mag. (Note that it is 0.54 mag brighter in R1.) We derive the following magnitudes 0.3 days after the GRB: time (d) Mag dMag Exposure Filter 0.287871 20.98 0.13 6 x 300 Ic 0.304668 21.39 0.12 1 x 600 Rc 0.312191 21.40 0.12 1 x 600 Rc 0.319703 21.47 0.35 1 x 600 Rc Compared to the magnitude found by Xin et al., GCN 9431, this indicates the afterglow has faded by two magnitudes. The normal Rc - Ic color as well as the confirmation by Swift UVOT of a rising afterglow (Schady et al., GCN 9435) implies that it is not overly reddened, an alternate explanation by Holland et al., GCN 9432. No further observations are planned. This message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9437 SUBJECT: GRB 090529: optical observations DATE: 09/05/30 01:39:58 GMT FROM: Alexei Pozanenko at IKI, Moscow M. Andreev, A. Sergeev (Terskol Branch of Institute of Astronomy), A. Pozanenko (IKI) on behalf of larger GRB follow up collaboration report: We observed the optical afterglow (Xin et al. GCN 9431) of the Swift GRB 090529 (Sakamoto et al. GCN 9430) with the Z-600 telescope of Mt.Terskol observatory in R-filter between (UT) May 29 19:40 -- 20:20. In a combined image (20x120 s) we clearly detect the afterglow at the position (J2000) RA=14 09 52.55 Dec=+24 27 31.2 which is comparable with the afterglow position (Schady et al. GCN 9435, Kann et al. GCN 9436). The combined image finding chart can be found at http://grb.rssi.ru/GRB090529/GRB090529_Z600.JPG The photometry of the afterglow is undergoing. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9448 SUBJECT: GRB 090529: OSN optical observations DATE: 09/05/30 16:04:33 GMT FROM: Javier Gorosabel at Danish Space Res Inst J. Gorosabel (IAA-CSIC), A. de Ugarte Postigo (ESO, Santiago), F.J. Aceituno (OSN, IAA-CSIC), A.J. Castro-Tirado (IAA-CSIC), report on behalf of a larger collaboration: "We carried out R-band observations of the GRB 090529 XRT error circle (Sakamoto et al. GCN 9430; Osborne et al. GCN 9433) with the 1.5m OSN telescope. On May 29.87-29.93 UT (0.27-0.33 days afer the GRB) we detected the optical afterglow (Xin et al. GCN 9431) at R=21.44+/-0.06, against the same reference star used by Kann et al. (GCN 9436)." This message can be quoted. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9449 SUBJECT: GRB 090529: Swift-XRT refined analysis DATE: 09/05/30 16:48:02 GMT FROM: Boris Sbarufatti at INAF-IASF-Pa Sbarufatti B., Mangano V. (INAF-IASFPA) and T. Sakamoto (NASA/UMBC) report on behalf of the Swift Team: We have analyzed the first eleven orbits of Swift-XRT data of GRB 090529 (trigger 353540; Sakamoto, et al., GCN Circ. 9430), comprising 148 s taken in Windowed Timing (WT) mode, from T+203 s to T+352 s, and 8.2 ks in Photon Counting (PC) mode from T+353 s to T+46.7 ks. The best position for the X-ray afterglow is the XRT UVOT-enhanced position:RA, Dec = 212.46850, +24.45919 which is equivalent to: RA (J2000): 14h 09m 52.44s Dec (J2000): +24d 27' 33.1" with an uncertainty of 1.8 arcsec (radius, 90% confidence), as given by Osborne, et al., GCN Circ 9433. The 0.3-10 keV X-ray light curve is best fitted by a broken power-law wit early decay index -3.5+/-0.1, late decay index -0.7+/-0.2 and the break at (1100+180-140) s after the trigger. Faint flaring activity is detected along the decay. If decaying at the present rate, the predicted rate for T+ 48h is 2.8e-3 counts/s. However, we remark that a second break followed by a steepening of the light-curve is expected. The issue will be clarified when new data from the Swift observations (resumed today at 14:35 UT) will be available. The average spectrum of the steep decay part of the afterglow (WT + PC from T+203s to T+1.1 ks) is best fit by a power-law with indices 2.5+/-0.12 for the WT data and 2.2+/-0.15 for the PC data. The absorbing column is NH = (2.3-1.5+1.7)E20 cm^-2 slightly in excess with respect to the Galactic value of 1.61E20 cm^-2 (Kalberla et al. 2005). The average observed (unabsorbed) fluxes are 4.5(5.1)E-10 ergs cm^-2 s^-1 for the WT data and 1.5(1.6)E-11 for the PC data. The average spectrum of the flat decay part of the afterglow, consisting of 7.5 ks of PC data, observed from T+1.1 ks to T+46.7 ks (containing 120 photons) was fitted using Cash statistics with an absorbed power-law model. The absorbing column NH is (9 -7 +9)E20 cm^-2, consistent with the Galactic value, the photon index is 2.3+/-0.5. The observed (unabsorbed) flux is 5.3(7.2)E-13 ergs cm^-2 s^-1. The C-statistic is 66.4 with 101 bins. The count-rate to flux conversion factor is 4.7E-11. All quoted errors are at 90% confidence level. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00353540. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9453 SUBJECT: GRB 090529: NOT optical observations DATE: 09/05/30 23:53:10 GMT FROM: Giorgos Leloudas at Dark Cosmology Centre G. Leloudas, D. Malesani, D. Xu, J.P.U. Fynbo (DARK/NBI), P. Jakobsson (Univ. Iceland), M. E. Brown (Caltech), E.L. Schaller (Univ. Hawaii) and T. Liimets (NOT & Tartu Obs.) report on behalf of a larger collaboration: We observed the field of GRB 090529 (Sakamoto et al., GCN 9430) with the Nordic Optical Telescope equipped with MOSCA. 3x600s R-band frames were obtained starting on May 30, 21:22 UT, 1.29 days after the GRB. The optical afterglow (Xin et al., GCN 9431; Schady et al., GCN 9435) is well detected in our images. Using the same reference star as in Kann et al. (GCN 9436), we obtain R=22.5 for the afterglow. Comparison with the measurement by Kann et al., taken 0.3 days after the GRB, provides a decay index alpha = 0.72, assuming a power-law F (t) propto t^-alpha.//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9457 SUBJECT: GRB 090529: VLT spectroscopic redshift DATE: 09/05/31 10:39:47 GMT FROM: Valerio D'Elia at INAF-OAR D. Malesani, J. P. U. Fynbo, (DARK/NBI), V. D'Elia (INAF/OAR), A. de Ugarte Postigo (ESO), P. Jakobsson (U. Iceland), C. C. Thoene (INAF/OAB), report on behalf of a larger collaboration: Using FORS2 on the ESO Very Large Telescope, we have obtained low-resolution spectra (2 x 30 min) of the optical afterglow of GRB 090529 (Sakamoto et al., GCN 9430; Xin et al., GCN 9431) with the grism 300V, covering the wavelength range 3500-9200 AA. In the acquisition image the afterglow has a magnitude of R ~ 22.60 +-0.05. The first spectrum was taken starting on May 31.0778 UT (1.48 days after the GRB). In a preliminary analysis we detect strong absorption around 4416 AA which we interpret as Lyman-alpha at a redshift of z = 2.63. This value is supported by the detection of several metal absorption features, e.g., SiII 1526, CII 1335, SiII 1402 and CIV 1549, all at the common z=2.625, which we interpret as the redshift of the GRB. We thank the Paranal staff for excellent support, in particular Thomas Szeifert, Alain Smette, and Karla Aubel. We are also grateful to Lipin Xin for providing us with a finding chart. ------------------------------------------------- This mail sent through IMP: http://horde.org/imp/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9467 SUBJECT: GRB 090529: MITSuME optical observation DATE: 09/06/01 07:55:52 GMT FROM: Michitoshi Yoshida at Okayama Astrophysical Obs M. Yoshida, D. Kuroda, K. Yanagisawa, Y. Shimizu, S. Nagayama, H. Toda (OAO, NAOJ) and N. Kawai (Tokyo Tech) report on behalf of the MITSuME collaboration: We observed the field of GRB 090529 (Sakamoto et al. GCN 9430) with optical three color (g', Rc and Ic) CCD camera attached to the MITSuME 50cm telescope of Okayama Astrophysical Observatory. The observation started on 2009-05-29 14:51:47 UT. We found a faint source at the UVOT position reported by Schady et al. (GCN 9435) in g' band. Photometric results are listed below. We used USNO B1 catalog for flux calibration. #PDAY MID-UT T-EXP g' g'_err Rc Ic ---------------------------------------------------------- 0.03564 15:03:55 1200sec 20.3 0.4 >19.7 >18.9 ---------------------------------------------------------- //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9473 SUBJECT: GRB 090529B: Fermi GBM detection DATE: 09/06/01 15:04:50 GMT FROM: Arne Rau at MPE Arne Rau (MPE) reports on behalf of the Fermi GBM Team: "At 07:26:22.41 UT on 29 May 2009, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 090529B (trigger 265274784 / 090529310). The on-ground calculated location, using the GBM trigger data, is RA = 231.2, DEC = +32.2 (J2000 degrees, equivalent to 15 h 25 m, 32 d 12 '), with an uncertainty of 7.2 degrees (radius, 1-sigma containment, statistical only; there is additionally a systematic error which is currently estimated to be 2 to 3 degrees). The angle from the Fermi LAT boresight is 36 degrees. The GBM light curve consists of a single peak with a duration (T90) of about 5.1 s (8-1000 keV). The time-averaged spectrum from T0-1.792 s to T0+5.376 s is best fit by a Band function with Epeak = 142 +/- 56 keV, alpha = -0.7 +/- 0.3, and beta = -2.0 +/- 0.3 (chi squared 561 for 544 d.o.f.). The event fluence (8-1000 keV) in this time interval is (3.4 +/- 0.9)E-07 erg/cm^2. The 1.28-sec peak photon flux measured starting from T0+0.003 s in the 8-1000 keV band is 4.1 +/- 0.1 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: 9474 SUBJECT: GRB 090529C: Fermi GBM detection DATE: 09/06/01 15:09:17 GMT FROM: Arne Rau at MPE Arne Rau (MPE) reports on behalf of the Fermi GBM Team: "At 13:32:00.49 UT on 29 May 2009, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 090529C (trigger 265296722 / 090529564). The on-ground calculated location, using the GBM trigger data, is RA = 162.7, DEC = 47.3 (J2000 degrees, equivalent to 10 h 51 m, 47 d 18 '), with an uncertainty of 1.5 degrees (radius, 1-sigma containment, statistical only; there is additionally a systematic error which is currently estimated to be 2 to 3 degrees). The angle from the Fermi LAT boresight is 69 degrees. This burst was also independently detected by INTEGRAL SPI-ACS. The GBM light curve consists of two narrow pulses with a duration (T90) of about 10.4 s (8-1000 keV). The time-averaged spectrum from T0-0.002 s to T0+10.048 s is best fit by a Band function with Epeak = 188 +/- 15 keV, alpha = -0.84 +/- 0.05, and beta = -2.1 +/- 0.1 (chi squared 795 for 648 d.o.f.). The event fluence (8-1000 keV) in this time interval is (3.1 +/- 0.1)E-06 erg/cm^2. The 1.028-sec peak photon flux measured starting from T0+9.024 s in the 8-1000 keV band is 25 +/- 1 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog. We further report that the Fermi Observatory executed a maneuver following this trigger and tracked the burst location for the next 5 hours, subject to Earth-angle constraints. " //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9477 SUBJECT: GRB090529B: ROVOR Upper Limits DATE: 09/06/01 21:51:27 GMT FROM: J. Ward Moody at BYU Richard L. Pearson, Cameron J. Pace and J. Ward Moody report for Brigham Young University’s ROVOR team: We searched for GRB 090529B at the position specified by the Fermi notice processed at 07:27:20UT on 29 May 2009 (Fermi-GBM Ground Position notice, trigger 265274784, record 57). The notice reports a GRB position of 15h 36m 29s +37d 02’ 22” (J2000) with an error of 9.86 degrees. ROVOR’s 0.41 m telescope, with a FOV = 10 arcminutes, centered the frames at 15h 36m 26.924s (± 0.0990 arcseconds) +37d 04’ 28.748” (± 0.1145 arcseconds, J2000). Rau (GCN Circ. 9473) reports a ground calculated location of 15h 25m +32d 12’ with an uncertainty of 7.2 degrees. Our images are well within the degree of uncertainty reported by the Fermi trigger and within 1.9 degrees from the specified location in GCN Circ. 9473. ROVOR began retrieving data at 08:51:06.4UT (1.15 hrs post-burst). 25 x 60s frames were taken in the R band and 10 x 60s frames were taken in the V band. No optical afterglow was located after stacking the images and comparing them to the STScI Digital Sky Survey image of the same field. By using calibration stars from the nearby field of Mrk 501 (16h 53m 52.13s +39d 45’ 36.2”, J2000), limiting magnitudes of V > 20.7 ± 0.1mag and R > 21.4 ± 0.1mag were found. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9482 SUBJECT: GRB090529: Further NOT optical observations DATE: 09/06/02 21:57:20 GMT FROM: Dong Xu at DARK,NBI D. Xu, G. Leloudas, D. Malesani, J. P. U. Fynbo, J. Maund (DARK/NBI), P. Jakobsson (Univ. Iceland), and T. Liimets (NOT & Tartu Obs.) report on behalf of a larger collaboration: We continued to observe the field of GRB 090529 (Sakamoto et al., GCN 9430) with the Nordic Optical Telescope equipped with ALFOSC. We obtained 3x600 s R-band frames staring on June 01, 21:26:31 UT and ending on June 01, 22:00:52 UT. The mid-exposure time is 3.31 days after the burst. The optical afterglow (Xin et al., GCN 9431; Schady et al., GCN 9435) is still detected in the stacked frame. Using the same reference star as in Kann et al. (GCN 9436) and in Leloudas et al. (GCN 9453), we obtain R=22.8+/-0.1 for the afterglow. Measurements by Kann et al. (0.3 day after the burst) and Leloudas et al. (1.29 days after the burst) indicate an optical power-law decay index of alpha1=0.72. Our new observation indicates that the optical decay became even slower, with an index of alpha2=0.3 between our two obs epochs. In contrast, during the whole period of 0.3 - 3.31 days the X-ray afterglow decays with the index of ~1.0 (ref, Evans et al. 2009). The slow optical decay may be also due to the presence of a fairly bright host galaxy. Further optical observations are encouraged. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9485 SUBJECT: GRB 090529A: RTT150 Optical Observations DATE: 09/06/03 15:51:34 GMT FROM: Solen Balman at METU S. Balman (METU), M. Parmaksizoglu (TUG) Z. Eker (TUG), U. Kiziloglu (METU), E. Gogus (Sabanci Uni.) I. Bikmaev, N. Sakhibullin (KSU/AST) R. Burenin, M. Pavlinsky, R. Sunyaev (IKI), report: We observed the field of GRB090529A (trigger=353540, Sakamato et al. 2009 GCN Circ. 9430, also GCN Circ. 9431-9436,9448,9449,9457) with the Russian-Turkish 1.5-m telescope (RTT150, Bakirlitepe, TUBITAK National Observatory, Turkey) on 30 May starting at 00:09:01.86 UT about 9.94 hours (0.414 d) after the burst using the TFOSC CCD (burst detected at 14:12:35 UT with Swift Burst Alert Telescope (BAT)). We obtained one 900 sec exposure using the R band filter (Bessell filter). We found the afterglow candidate at the location designated by the Swift XRT position given by Osborne et al. 2009 GCN Circ. 9433. We performed PSF photometry using DAOPHOT within MIDAS software on the 13.3 by 13.3 arcmin field around the afterglow candidate. We calibrated the R band magnitude using the same USNO-B1 reference star noted by Kann et al. 2009 GCN Circ. 9436. The GRB090529 afterglow candidate is detected at R = 21.2+/-0.2 mag. This message can be cited. [GCN OPS NOTE(03jun09): Per author's request, the Subject line was changed.] //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9610 SUBJECT: GRB 090529: Mt.Terskol optical observations DATE: 09/07/03 22:10:53 GMT FROM: Alexei Pozanenko at IKI, Moscow M. Andreev, A. Sergeev (Terskol Branch of Institute of Astronomy), A. Pozanenko (IKI) on behalf of larger GRB follow up collaboration report: We report a photometry of the optical afterglow (Xin et al. GCN 9431) of the Swift GRB 090529 (Sakamoto et al. GCN 9430) observed with the Z-600 telescope of Mt.Terskol observatory in R-filter (Andreev et al, GCN 9437). The photometry is based on reference star USNO-B1.0 1144-0210607 (J2000) 14 09 58.32 +24 27 35.6), assuming R=16.46: T0+ Filter, Exposure, mag., (d) (s) 0.2420 R 20x120 21.13 +/- 0.2 //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9611 SUBJECT: GRB 090529: MTM-500 optical observations DATE: 09/07/03 22:16:50 GMT FROM: Alexei Pozanenko at IKI, Moscow A. Volnova (SAI MSU), K. Naumov, V. Kouprianov, A. Devyatkin (Pulkovo Observatory), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: We observed the field of the Swift GRB 090529 (Sakamoto et al. GCN 9430) with MTM-500 (0.5m) telescope of Kislovodsk solar station (43d 44.77' N, 42d 31.42' W) of the Pulkovo observatory in two series in R-filter starting May 29 (UT) 19:58. We do not detect optical afterglow (Xin et al. GCN 9431). The upper limits of combined images based on USNO-B1.0 are following: T0+ Filter, Exposure, mag., (d) (s) 0.2817 R 60x60 > 19.3 0.3324 R 55x60 > 19.4 //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9612 SUBJECT: GRB 090529: CrAO optical upper limit DATE: 09/07/03 22:27:56 GMT FROM: Alexei Pozanenko at IKI, Moscow D. Shakhovkoy, V. Rumyantsev (CrAO), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: We observed the field of the Swift GRB 090529 (Sakamoto et al. GCN 9430) with AZT-11 telescope of CrAO between (UT) May 29 18:41 -- 19:42 under poor weather conditions. We do not detect optical afterglow (Xin et al. GCN 9431). Upper limit of a stacked image based on USNO-B1.0 star (RA=14 09 47.65 Dec=+24 27 44.30) assuming I=17.54 is following: T0+ Filter, Exposure, mag. (d) (s) 0.2075 I 20x180 > 20.3