//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9280 SUBJECT: GRB 090429: Swift detection of a burst DATE: 09/04/29 05:29:46 GMT FROM: David Palmer at LANL C. B. Markwardt (CRESST/GSFC/UMD), S. D. Barthelmy (GSFC), P. A. Evans (U Leicester), N. Gehrels (NASA/GSFC), K. L. Page (U Leicester), D. M. Palmer (LANL), B. A. Rowlinson (U Leicester), M. H. Siegel (PSU), M. Stamatikos (NASA/ORAU) and T. N. Ukwatta (GSFC/GWU) report on behalf of the Swift Team: At 04:53:39 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 090429 (trigger=350853). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 90.559, -52.386 which is RA(J2000) = 06h 02m 14s Dec(J2000) = -52d 23' 09" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a broad peak with a duration of about 25 sec. The peak count rate was ~700 counts/sec (15-350 keV), at ~5 sec after the trigger. The XRT began observing the field at 04:54:38.0 UT, 58.1 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 90.5548, -52.3855 which is equivalent to: RA(J2000) = 06h 02m 13.15s Dec(J2000) = -52d 23' 07.8" with an uncertainty of 5.1 arcseconds (radius, 90% containment). This location is 9.4 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 66 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 0.06. Because this burst was detected as part of the sub-threshold program (see GCN 8943) with a BAT image significance of only 5.64 sigma, GCN notices were not generated until the source was confirmed using XRT data. Burst Advocate for this burst is C. B. Markwardt (Craig.Markwardt 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: 9281 SUBJECT: GRB 090429B: Swift detection of a burst DATE: 09/04/29 05:47:53 GMT FROM: David Palmer at LANL T. N. Ukwatta (GSFC/GWU), S. D. Barthelmy (GSFC), P. A. Evans (U Leicester), N. Gehrels (NASA/GSFC), C. B. Markwardt (CRESST/GSFC/UMD), K. L. Page (U Leicester), D. M. Palmer (LANL), B. A. Rowlinson (U Leicester), M. H. Siegel (PSU), M. Stamatikos (NASA/ORAU) and L. Vetere (PSU) report on behalf of the Swift Team: At 05:30:03 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 090429B (trigger=350854). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 210.704, +32.163 which is RA(J2000) = 14h 02m 49s Dec(J2000) = +32d 09' 48" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed three peaks with a duration of about 5 sec. The peak count rate was ~4000 counts/sec (15-350 keV), at ~0 sec after the trigger. The XRT began observing the field at 05:31:50.0 UT, 106.6 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source with an enhanced position: RA, Dec 210.6670, 32.1707 which is equivalent to: RA(J2000) = 14h 02m 40.09s Dec(J2000) = +32d 10' 14.6" with an uncertainty of 2.3 arcseconds (radius, 90% containment). This location is 116 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 consistent with the Galactic value of 1.2e+20 cm^-2 (Kalberla et al. 2005). UVOT took a finding chart exposure of 150 seconds with the White filter starting 99 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 25% of the BAT error circle but does not overlap 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 BAT error circle and 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 0.01. Burst Advocate for this burst is T. N. Ukwatta (tilan.ukwatta AT gmail.com). 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: 9282 SUBJECT: GRB 090429B: Super-LOTIS early observations DATE: 09/04/29 06:40:06 GMT FROM: Adria C. Updike at Clemson U Adria C. Updike (Clemson University), G. Grant Williams (MMTO Observatory), Peter A. Milne (Steward Observatory), and Dieter H. Hartmann (Clemson University) report: The 0.6m Super-LOTIS telescope at Kitt Peak National Observatory began observing the field of GRB 090429B 40 seconds after the trigger (Ukwatta et al., GCN 9281) under good conditions. Observations consisted sets of 10, 20, and 60 second exposures. No new sources are found in the XRT error circle. The results of the stacked exposures are given below; time is given in seconds after the trigger (midtime of stack). Magnitudes were determined relative to the USNO B1.0 catalog. Band Exposures Time Mag ------------------------------------------- R 5 x 10sec 80 > 17 R 10 x 60sec 580 > 19 Observations are continuing. This message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9283 SUBJECT: GRB 090429B: GROND Observations DATE: 09/04/29 07:58:36 GMT FROM: Aybuke Kupcu Yoldas at ESO F. Olivares (MPE Garching), A. Kupcu Yoldas (ESO), J. Greiner, T. Kruehler, A. Yoldas (both MPE Garching) report on behalf of the GROND team: We observed the field of GRB 090429B (Swift trigger 350854; Ukwatta et al., GCN #9281) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2 m ESO/MPI telescope at La Silla Observatory (Chile). Observations started at 05:43 UT, ~13 minutes after the GRB trigger and continued until the source reached the 20 deg horizon limit. They are performed at an average seeing of 1.2 and at an average airmass of 2.5. We do not detect any source within the Swift-XRT error circle reported by Ukwatta et al. (GCN #9281) down to the following limits (based on 4 minutes of exposure time, all in AB system): g' > 23.4 mag r' > 23.3 mag i' > 22.4 mag z' > 21.8 mag J > 21.5 mag H > 20.2 mag K > 19.6 mag Quoted upper limits have been derived using USNO and 2MASS field stars as reference. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9284 SUBJECT: GRB 090429B: VLT upper limits DATE: 09/04/29 08:30:22 GMT FROM: Paolo D'Avanzo at INAF-OAB Paolo D'Avanzo (Univ. Milano-Bicocca & INAF/Brera), Andrew J. Levan (Univ. Warwick), Daniele Malesani (DARK/NBI), Christina C. Thoene (INAF/Brera), Johan P. U. Fynbo, Jens Hjorth (DARK/NBI), Nial Tanvir (Univ. Leicester), report on behalf of a larger collaboration: We observed the field of GRB 090429B (Ukwatta et al. GCN 9281) with the ESO-VLT in imaging mode with the FORS2 camera. Observations started about 1 hr after the burst. In our stacked images, no afterglow is detected down to the following 3sigma limits: R > 25.3 z > 23.5 Photometry has been calibrated against USNOB1 catalogue and the SDSS. We acknowledge support from the Paranal staff, in particular E. Mason and P. Lynam. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9286 SUBJECT: GRB090429B: Gemini-N infrared IR candidate DATE: 09/04/29 10:45:17 GMT FROM: Antonino Cucchiara at PSU A. Cucchiara (PSU), A. Levan (U. Warwick), N. Tanvir (U. Leicester), D. B. Fox (PSU) and E. Berger (Harvard U.) report: "On April 29.35 UT we imaged the field of Swift GRB 090429 (Ukwatta et al., GCN 9281) with NIRI on the Gemini-North telescope. We obtained images in J,H and K for a total exposure time of 9, 4.5 and 9 minutes respectively. In the coadded images we identify a possible IR counterpart inside the XRT error circle at the coordinates: RA (J2000): 14:02:40.05 Dec (J2000): +32:10:14.32 with an uncertainty of 0.5". The estimated magnitude are: J = 21.79 +- 0.1 H = 20.08 +- 0.05 K = 19.15 +- 0.03 These values are calibrated using the 2MASS star at RA=14:02:42.20, Dec= +32:10:50.36. Although variability remains to be confirmed, the red J-H colour, coupled with the relatively blue (H-K) is suggestive of a break. Although this may be caused by dust the lack of apparent excess N_H in the X-ray spectrum (GCN 9281) suggests this may not be the case. Hence GRB 090429B should be considered a high-z candidate." We thank the Gemini-N staff for the support in performing this observations, in particular Scott Fisher and Kathy Roth." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9287 SUBJECT: GRB 090429A - Correction to XRT position DATE: 09/04/29 11:35:56 GMT FROM: Phil Evans at U of Leicester P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team: The onboard XRT position for GRB 090429A (Markwardt et al. GCN. Circ 9280) delivered as an XRT position notice and given in GCN 9280 was incorrect. Inspection of the images reveals a cosmic ray 52 arcsec from the GRB which affected the onboard centroid. The correct position of the XRT afterglow is: RA, Dec= 90.5568, -52.3886 which is equivalent to: RA(J2000) = 06 02 13.63 Dec(J2000) = -52 23 18.9 with an uncertainty of 4.8 arcsec (radius, 90% confidence). This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9288 SUBJECT: GRB 090429B: Enhanced Swift-XRT position DATE: 09/04/29 11:44:00 GMT FROM: Phil Evans at U of Leicester A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) report on behalf of the Swift-XRT team. Using 862 s of XRT Photon Counting mode data and 1 UVOT images for GRB 090429B, 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 = 210.66707, +32.17072 which is equivalent to: RA (J2000): 14h 02m 40.10s Dec (J2000): +32d 10' 14.6" 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: 9289 SUBJECT: GRB 090429A: Swift-BAT refined analysis DATE: 09/04/29 11:56:38 GMT FROM: Scott Barthelmy at NASA/GSFC 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), 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-61 to T+302 sec from the recent telemetry downlink, we report further analysis of BAT GRB 090429A (trigger #350853) (Markwardt, et al., GCN Circ. 9280). The BAT ground-calculated position is RA, Dec = 90.573, -52.389 deg, which is RA(J2000) = 06h 02m 17.5s Dec(J2000) = -52d 23' 19.0" with an uncertainty of 1.7 arcmin, (radius, sys+stat, 90% containment). The partial coding was 100%. The mask-weighted light curve shows a relatively smooth structure with a couple overlapping peaks starting at ~T-12 sec and peaking at T_zero. The main peak ends around T+40 sec with a long weak tail extending out to ~T+200 sec. T90 (15-350 keV) is 188 +- 37 sec (estimated error including systematics). The time-averaged spectrum from T-10.8 to T+203.0 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.55 +- 0.22. The fluence in the 15-150 keV band is 1.0 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T-0.35 sec in the 15-150 keV band is 0.6 +- 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/350853/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9290 SUBJECT: GRB 090429B: Swift-BAT refined analysis DATE: 09/04/29 12:09:35 GMT FROM: Scott Barthelmy at NASA/GSFC M. Stamatikos (GSFC/ORAU), 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), A. M. Parsons (GSFC), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), 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 090429B (trigger #350854) (Ukwatta, et al., GCN Circ. 9281). The BAT ground-calculated position is RA, Dec = 210.672, 32.167 deg, which is RA(J2000) = 14h 02m 41.2s Dec(J2000) = +32d 10' 02.0" with an uncertainty of 1.3 arcmin, (radius, sys+stat, 90% containment). The partial coding was 84%. The mask-weighted light curve shows a main peak starting at ~T-4 sec, peaking at ~T-0.1 sec, and ending around T+3 sec. There are two very weak peaks: ~T+30 to ~T+70 sec, and ~T+100 to ~T+110 sec. T90 (15-350 keV) is 5.5 +- 1.0 sec (estimated error including systematics). The time-averaged spectrum from T-4.5 to T+2.4 sec is best fit by a power law with an exponential cutoff. This fit gives a photon index 0.47 +- 0.77, and Epeak of 42.1 +- 5.6 keV (chi squared 29.6 for 56 d.o.f.). For this model the total fluence in the 15-150 keV band is 3.1 +- 0.3 x 10^-7 erg/cm2 and the 1-sec peak flux measured from T-0.28 sec in the 15-150 keV band is 1.6 +- 0.2 ph/cm2/sec. A fit to a simple power law gives a photon index of 1.96 +- 0.13 (chi squared 45.3 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/350854/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9291 SUBJECT: GRB 090429B: RIMOTS optical upper limits DATE: 09/04/29 14:05:00 GMT FROM: Kenta Kono at Miyazaki U K.Kono, E.Sonoda, N.Ohmori, H.hayasi, K.Noda, A.Daikyuji, Y.Nisioka, M.Yamauchi (University of Miyazaki) We have observed the field covering the error circle of GRB09042 (Swift trigger 350854, GCN 9281, T. N. Ukwatta et al.) with the unfiltered CCD camera on the 30-cm telescope at University of Miyazaki. The observation was started 11:29:13 UT, about 6.0 hr 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. (GCN 9281, T. N. Ukwatta et al. GCN 9288, A.P. Beardmore et al. GCN 9290, M. Stamatikos et al.) the upper limits are as follows: -------------------------------------------------------------- Start(UT) End(UT) Num. of frames Limit (mag.) -------------------------------------------------------------- 11:29:13 11:29:33 1 16.4 11:29:13 12:04:10 28 17.9 --------------------------------------------------------------- //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9297 SUBJECT: GRB 090429A: Enhanced Swift-XRT position DATE: 09/04/29 18:20:30 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 945 s of XRT Photon Counting mode data and 1 UVOT images for GRB 090429A, 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 = 90.55469, -52.38758 which is equivalent to: RA (J2000): 06h 02m 13.13s Dec (J2000): -52d 23' 15.3" 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, arXiv:0812.3662). This circular was automatically generated, and is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9298 SUBJECT: GRB 090429B: Swift XRT refined analysis DATE: 09/04/29 20:14:12 GMT FROM: Antonia Rowlinson at U.of Leicester A. Rowlinson (U. Leicester) and T. N. Ukwatta (GSFC/GWU) report on behalf of the Swift-XRT team: We have analysed 8.9 ks of XRT data for GRB 090429B (Ukwatta et al. GCN Circ. 9281), from 104 s to 29.9 ks after the BAT trigger. The data are entirely in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Beardmore et al. (GCN. Circ 9288). The light curve initially shows a slow rise, which can be fitted with a power-law of index 0.89 (+0.36, -0.46). At around T+642 s the light curve breaks to a power-law decay, with index 1.20 (+0.11, -0.10). A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.00 (+0.15, -0.24). The best-fitting absorption column is 10.0 (+4.2, -5.3) x 10^20, in excess of the Galactic value of 1.2 x 10^20 cm^-2 (Kalberla et al. 2005). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.8 x 10^-11 (4.9 x 10^-11) erg cm^-2 count^-1. If the light curve continues to decay with a power-law decay index of 1.20, the count rate at T+24 hours will be 0.0014 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 5.3 x 10^-14 (6.9 x 10^-14) erg cm^-2 s^-1. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00350854. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9303 SUBJECT: GRB 090429A: GROND upper limits DATE: 09/04/30 09:16:41 GMT FROM: Thomas Kruehler at MPE/MPI F. Olivares, T. Kruehler, J. Greiner (all MPE) report on behalf of the GROND team: We observed the field of GRB 090429A (Swift trigger 350853, Markwardt et al.,GCN #9280) simultaneously in g'r'i'z'JHK with GROND mounted at the 2.2m ESO/MPI telescope at La Silla Observatory (Chile). Observations started on 30 Apr. 2009 at 01:05 UT, 20.2 h after the burst, and consisted of a set of images with a total integration time of 28 min in JHK and 32 min in g'r'i'z'. In stacked images we do not detect any object inside the enhanced XRT errorcircle (Evans et al., GCN #9297) down to the following AB magnitudes: g' > 23.4 r' > 23.3 i' > 22.6 z' > 22.2 J > 21.8 H > 20.7 K > 20.0 These upper limits have been obtained using 2MASS field stars and the GROND zeropoints as reference. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9304 SUBJECT: GRB 090429A: Swift-XRT refined analysis DATE: 09/04/30 10:39:40 GMT FROM: Phil Evans at U of Leicester P.A. Evans (U. Leicester) and C. B. Markwardt (CRESST/GSFC/UMD) report on behalf of the Swift-XRT team: We have analysed 6 ks of XRT data for GRB 090429A (Markwardt et al. GCN Circ. 9280). The first observation comprises a continuous observation from T0+64 s to T0+255 s with the data entirely in Windowed Timing (WT) mode. The second observation covers the range T0+35 to T0+64 ks, and contains 5.8 ks of Photon Counting (PC) mode data. The enhanced XRT position for this burst was given by Evans et al. (GCN. Circ 9297). The first observation shows a number of flares superimposed on a short, initial rise which breaks at T0+100s to a power-law decay with index 2.7 (+0.3, -0.2). The later PC mode data lie orders of magnitude above the extrapolation of this decay; the addition of a break around T0+1 ks to a decay with power-law index 0.56 (+0.12, -0.06) produces a good fit to the data. Due to the large observing gap the behaviour of the light curve in the interval T0+255 s to T0+35 ks is unknown; if it is more complex than the simple behaviour we have modelled the final decay index could differ significantly from the 0.56 (+0.12, -0.06) value we obtained. A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.0 (+1.0, -0.7). The best-fitting absorption column is 1.20 (+2.36, -0.77) x 10^21 cm^-2, consistent with the Galactic value of 4.2 x 10^20 cm^-2 (Kalberla et al. 2005). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.8 x 10^-11 (5.0 x 10^-11) erg cm^-2 count^-1. If the light curve continues to decay with a power-law decay index of 0.56, the count rate at T+48 hours will be 5.9 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.2 x 10^-13 (2.9 x 10^-13) erg cm^-2 s^-1. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00350853. This circular is an official product of the Swift-XRT team. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9306 SUBJECT: GRB 090429B: Gemini-N further nIR observations DATE: 09/04/30 11:38:26 GMT FROM: Nial Tanvir at IofA U.Cambridge A. Levan (U. Warwick), A. Cucchiara (PSU), N. Tanvir (U. Leicester), D. Fox (PSU) & E. Berger (Harvard U.) report: We re-observed the field of GRB 090429B with NIRI on Gemini-N, beginning about 30-Apr 08:00 (UT). The infra-red source reported by Cucchiara et al. (GCN 9286) is detected, but has faded significantly to K=20.0 +/- 0.2 mag. We thus confirm that this source is the afterglow of the burst. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9308 SUBJECT: GRB 090429A: Swift/UVOT Upper Limits DATE: 09/04/30 15:15:24 GMT FROM: Stephen Holland at USRA/NASA/GSFC/SSC M. M. Chester (PSU), S. T. Holland (CRESST/GSFC/USRA) and C. B. Markwardt (CRESST/GSFC/UMD) report on the behalf of the Swift UVOT team: The Swift/UVOT observed the field of GRB 090429A starting 49 s after the BAT trigger (Markwardt, et al., 2009, GCN Circ. 9280). Settled exposures started at T+67 s. We do not find any new source, relative to the DSS, USNO-B1.0, or 2MASS at the position of the XRT afterglow (Evans, et al. 2009, GCN Circ. 9297). Preliminary 3-sigma upper limits for detecting a source in the white finding chart and the co-added images, using a 2.5 arcsecond radius circular aperture, are Filter T_start T_stop Exp(s) Mag ---------------------------------------------- white (fc) 67 217 147 >21.7 v 35,736 58,902 114 >19.8 b 40,727 63,010 1697 >22.1 u 52,833 53,121 284 >21.0 uvw1 50,447 86,297 3336 >22.2 uvm2 44,777 47,341 659 >20.9 uvw2 34,829 57,197 1746 >21.9 white 63,015 63,137 120 >21.5 ---------------------------------------------- The quoted upper limits have not been corrected for the expected Galactic extinction along the line of sight corresponding to a reddening of E_{B-V} = 0.06 mag (Schlegel, et al., 1998, ApJS, 500, 525). All photometry is on the UVOT photometry system described in Poole et al. (2008, MNRAS, 383, 627). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9309 SUBJECT: GRB 090429B: Swift/UVOT Upper Limits DATE: 09/04/30 16:03:10 GMT FROM: Margaret Chester at PSU M. M. Chester (PSU) and T. N. Ukwatta (GSFC/GWU) report on the behalf of the Swift/UVOT team: The Swift/UVOT observed the field of GRB 090429B starting 78 s after the BAT trigger (Ukwatta et al. 2009, GCN Circ. 9281). Settled exposures started at T+99 s. We do not find any new source at the position of the XRT afterglow (Beardmore et al. 2009, GCN Circ. 9288). Preliminary 3-sigma upper limits for detecting a source in the white finding chart and the co-added images, using a 5 arcsecond radius circular aperture, are: Filter T_start T_stop Exp(s) Mag ---------------------------------------------- white (fc) 99 249 150 >21.0 white 591 10856 1241 >22.2 v 640 12550 1213 >20.6 b 567 6769 381 >20.8 u 311 6621 669 >20.8 uvw1 690 6416 419 >20.5 uvm2 665 6211 439 >21.4 uvw2 616 11762 1339 >20.3 ---------------------------------------------- The quoted upper limits have not been corrected for the expected Galactic extinction corresponding to a reddening of E_{B-V} = 0.015 in the direction of the XRT position (Schlegel, et al. 1998, ApJS, 500, 525). All photometry is on the UVOT photometry system described in Poole et al. (2008, MNRAS, 383, 627). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9310 SUBJECT: GRB 090429C: Fermi GBM detection DATE: 09/04/30 21:44:51 GMT FROM: Sheila McBreen at MPE Sheila McBreen (UCD/MPE) reports on behalf of the Fermi GBM Team: "At 12:43:25.70 UT on 29 April 2009, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 090429C (trigger 262701807 / 090429530). The on-ground calculated location, using the GBM trigger data, is RA = 261.4, DEC = +55.5 (J2000 degrees, equivalent to 17 h 26 m, +55 d 30 '), with an uncertainty of 4.9 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 112 degrees. The GBM light curve consists of two pulses with a duration of about 13 s (8-1000 keV). The time-averaged spectrum from T0-2 s to T0+11 s is adequately fit by a simple power law function with index -1.43 +/- 0.04 (chi squared 513 for 471 d.o.f.). The event fluence (8-1000 keV) in this time interval is (3.7 +/- 0.1)E-6 erg/cm^2. The 0.256 sec peak photon flux measured starting from T0+0.768 s in the 8-1000 keV band is 6.7 +/- 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: 9311 SUBJECT: GRB 090429D: Fermi GBM detection DATE: 09/04/30 22:09:24 GMT FROM: Narayana Bhat at U Alabama/Huntsville/GBM P. N. Bhat (UAH) reports on behalf of the Fermi GBM Team: "At 18:03:57.51 UT on 29 April 2009, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 090429D (trigger 262721039 / 090429753). The on-ground calculated location, using the GBM trigger data, is RA = 125.2, DEC = 6.2 (J2000 degrees, equivalent to 08 h 20.8 m, 06 d 12'), with an uncertainty of 4.6 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 33 degrees. [This burst was also independently detected by Konus Wind. Swift BAT confirms this GRB which occurred while it was slewing.] The GBM light curve consists of 3 short pulses (two which occurred before the trigger) with a duration (T90) of about 11 s (8-1000 keV). The time-averaged spectrum from T0-13.248 s to T0+1.088 s is adequately fit by a power law function with an exponential high energy cutoff. The power law index is -0.87 +/- 0.27 and the cutoff energy, parametrized as Epeak, is 223 +/- 72.5 keV (chi squared 459 for 487 d.o.f.). The event fluence (8-1000 keV) in this time interval is (1.6 +/- 0.3)E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0 s in the 8-1000 keV band is 0.86 +/- 0.16 ph/s/cm^2. [A Band function fits the spectrum equally well (chi squared 456 for 486 d.o.f.) with Epeak= 152.8 +/- 92.4 keV, alpha = -0.66 +/- 0.53 and beta = -1.88+/- 0.32.] The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog." //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9318 SUBJECT: GRB 090429A: ROVOR magnitude limit DATE: 09/05/01 15:46:47 GMT FROM: J. Ward Moody at BYU Richard L. Pearson and J. Ward Moody report for Brigham Young Univerisity’s ROVOR team: We observed the field around GRB 090429A (Swift trigger 350853, Markwardt et al., GCN 9280) with the ROVOR (Robotic Observatory for Variable Object Research) 16” telescope from Delta, Utah. Beginning 30 April 2009 at 03:46:50 UT (22.3 hours after outburst), observations were obtained for a complete integration time of 50 minutes in white light. No detection was made after stacking the images. Using the magnitude limits established by Olivares et al., GCN Circ. 9303 on the 2.2m ESO/MPI telescope at La Silla Observatory, we estimate a magnitude limit of 22 ± 1 mag on these observations. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 12043 SUBJECT: EVLA afterglow limits on the high z GRB090429B DATE: 11/05/28 12:16:12 GMT FROM: Dale A. Frail at NRAO Dale A. Frail (NRAO), Ashley Zauderer (Harvard), Edo Berger (Harvard) and Poonam Chandra (RMC) report on behalf of a larger collaboration: We used the EVLA to image a field toward the Swift burst GRB 090429B (GCNs 9281, 9288, 9290, 9298), for which a photometric redshift of z=9.4 has been recently claimed (Cucchiara et al. astro-ph/1105.4915). The EVLA observed at two frequencies (1 GHz bandwidth each) centered at 4.93 GHz and 6.68 GHz on 2011 April 4.38 UT and 2011 May 6.13 UT. No radio source is detected at the NIR afterglow position. Combining the data from both epochs we derive a 3-sigma limit of 16.6 microJy. This limit corresponds to a spectral luminosity of 2e31 erg/s/Hz. We also reduced archival data taken at a frequency of 8.46 GHz on 2009 April 30.28 UT. The 3-sigma limit for this observation is 132 microJy.