//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9325 SUBJECT: GRB 090509: Swift detection of a burst DATE: 09/05/09 05:21:22 GMT FROM: Scott Barthelmy at NASA/GSFC D. Grupe (PSU), S. D. Barthelmy (GSFC), M. M. Chester (PSU), H. A. Krimm (CRESST/GSFC/USRA), F. E. Marshall (NASA/GSFC), D. M. Palmer (LANL), J. L. Racusin (PSU) and M. H. Siegel (PSU) report on behalf of the Swift Team: At 05:10:03 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 090509 (trigger=351525). Swift did not slew to this burst. The BAT on-board calculated location is RA, Dec 241.404, -28.404 which is RA(J2000) = 16h 05m 37s Dec(J2000) = -28d 24' 12" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows multiple peaks with a duration of about 30 sec. The peak count rate was ~1300 counts/sec (15-350 keV), at ~20 sec after the trigger. Due to the Moon observing constraint, Swift cannot slew to the BAT position until May 12. There will thus be no XRT or UVOT data for this trigger. Burst Advocate for this burst is D. Grupe (grupe 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: 9326 SUBJECT: GRB 090509: GROND afterglow candidate DATE: 09/05/09 06:00:25 GMT FROM: Thomas Kruehler at MPE/MPI F. Olivares, J. Greiner, T. Kruehler (all MPE Garching) and S. Klose (TLS) report on behalf of the GROND team: We observed the field of GRB 090509 (Swift trigger 351525; Grupe et al., GCN #9325) 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). We detect a bright uncatalogued source in all bands at 16:05:39.01 -28:23:59.7 with a magnitude of r' = 17.9 at 15 min after the burst, calibrated using the GROND zeropoint. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9327 SUBJECT: GRB 090509: REM NIR afterglow DATE: 09/05/09 06:03:38 GMT FROM: Stefano Covino at Brera Astronomical Observatory S. Covino, P. D'Avanzo, L.A. Antonelli, D. Fugazza, L. Calzoletti, S. Campana, G. Chincarini, M.L. Conciatore, S. Cutini, V. D'Elia, F. D'Alessio, F. Fiore, P. Goldoni, D. Guetta, C. Guidorzi, G.L. Israel, E. Maiorano, N. Masetti, A. Melandri, E.J.A. Meurs, L. Nicastro, E. Palazzi, E. Pian, S. Piranomonte, L. Stella, G. Stratta, G. Tagliaferri, G. Tosti, V. Testa, S.D. Vergani, F. Vitali report on behalf of the REM team: The robotic 60-cm REM telescope located at La Silla (Chile) observed automatically the field of the GRB 090509 (Grupe et al. GCN9325) starting about 3min after the burst. We detect a fading object in the BAT error circle in our first H-band images at H~14.3 at coordinates: RA(J2000) 16:05:38.99; Dec(J2000) -28:23:58.7 with 1 arcsec error. Moon is only at about 15 deg preventing useful optical observations. [GCN OPS NOTE(09may09): Per author's request, the "R~14.3" was changed to "H~14.3".] [GCN OPS NOTE(09may09): Per self request, D.Malesani was removed from the author list.] //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9328 SUBJECT: GRB 090509: GROND further analysis and redshift limit DATE: 09/05/09 12:31:34 GMT FROM: Thomas Kruehler at MPE/MPI F. Olivares, T. Kruehler (MPE Garching), S. Klose (Tautenburg), and J. Greiner (MPE Garching) report on behalf of the GROND team: In addition to our previous GCN (Olivares et al., GCN #9326) we report here the observed preliminary magnitudes (in the AB system) for the afterglow (GCN #9326 and Covino et al., GCN #9327) of GRB 090509 (Grupe et al., GCN #9325). Based on 8 min of effective exposure starting at 5:22 UT (12 minutes after the trigger), we measure g = 18.12 +/- 0.01 r = 17.75 +/- 0.01 i = 17.48 +/- 0.01 z = 17.22 +/- 0.01 J = 16.87 +/- 0.07 H = 16.57 +/- 0.12 K = 16.31 +/- 0.17 The quoted error is statistical only. There is an additional systematic error from the calibration against the GROND zeropoints and 2MASS field stars which is expected to be in the 0.1 mag range. After correcting for a Galactic foreground extinction corresponding to a reddening of E_(B-V)=0.206 mag (Schlegel et al.), the g' to K band is well described with a single power law. This implies, that Lyman alpha is below or very close to the blue edge of the g' band, and constrains the redshift to smaller than z < 3.0 (90% confidence limit). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9333 SUBJECT: GRB 090509, SMARTS optical/IR afterglow observations DATE: 09/05/10 02:05:34 GMT FROM: Bethany Cobb at UC Berkeley B. E. Cobb (UC Berkeley) reports: Using the ANDICAM instrument on the 1.3m telescope at CTIO, we obtained optical/IR imaging of the error region of GRB 090509 (Grupe et al. GCN 9325) beginning approximately 0.8 hours post-burst (2009-05-09 05:59 UT). Several dithered images were obtained in each filter, with total summed exposure times of 180s in each of BRIJK and 120s in each of H and V. The GRB afterglow (Olivares et al. GCN 9326, Covino et al. GCN 9327) is detected in all filters with the following magnitudes at a mid-exposure time of 2009-05-09 06:14 UT (1.07 hours post-burst): B= 20.18 +/- 0.13 V= 19.68 +/- 0.16 R= 19.02 +/- 0.10 I= 18.76 +/- 0.09 J= 17.70 +/- 0.16 H= 17.07 +/- 0.15 K= 16.48 +/- 0.22 (Optical photometry is calibrated against Landolt standard stars and IR photometry is calibrated against 2MASS stars in the field.) //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9335 SUBJECT: GRB 090509: Swift-BAT refined analysis DATE: 09/05/10 05:41:38 GMT FROM: Scott Barthelmy at NASA/GSFC J. Tueller (GSFC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), D. Grupe (PSU), 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), 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 090509 (trigger #351525) (Grupe, et al., GCN Circ. 9325). The BAT ground-calculated position is RA, Dec = 241.426, -28.420 deg, which is RA(J2000) = 16h 05m 42.3s Dec(J2000) = -28d 25' 12.6" with an uncertainty of 1.9 arcmin, (radius, sys+stat, 90% containment). The partial coding was 29%. The mask-weighted light curve shows multiple overlapping peaks starting at ~T-4 sec, peaking at ~T+21 sec, and ending at ~T=3 sec. T90 (15-350 keV) is 20.4 +- 1.7 sec (estimated error including systematics). The time-averaged spectrum from T-1.1 to T+22.4 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.54 +- 0.16. The fluence in the 15-150 keV band is 1.1 +- 0.1 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+20.73 sec in the 15-150 keV band is 1.5 +- 0.3 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/351525/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9349 SUBJECT: GRB 090509, further Swift-BAT refined analysis DATE: 09/05/11 17:15:49 GMT FROM: Hans Krimm at NASA-GSFC H. A. Krimm (GSFC/USRA), S. D. Barthelmy (GSFC), and J. R. Cummings (GSFC/UMBC) for the Swift-BAT team. Here we report on further analysis of GRB 090509 (Grupe et al., GCN Circ. 9325) based on additional event data received since GCN Circ. 9335 (Tueller et al.) was issued. The results given here supersede those from GCN Circ. 9335. Using the data set from T-239 to T+316 sec from the recent telemetry downlink, we report further analysis of BAT GRB 090509 (trigger #351525). The BAT ground-calculated position is RA, Dec = 241.422, -28.385 deg which is RA(J2000) = 16h 05m 41.3s Dec(J2000) = -28d 23' 04.4" with an uncertainty of 2.1 arcmin, (radius, sys+stat, 90% containment). The partial coding was 29%. The mask weighted light curve consists of two sets of peaks widely separated in time. The first complex contains multiple overlapping peaks starting at ~T-4 sec, peaking at ~T+21 sec, and ending at ~T+40 sec. The second complex also contains multiple overlapping peaks starting at ~T+240 sec, peaking at ~T+250 sec and continuing until at least ~T+300 sec, when a pre-planned slew caused the source to move out of the BAT field of view. However until ~T+950 sec the source was at a location outside the field of view where high energy (> 50 keV) photons from the source could have penetrated the BAT shield and contributed to the non-maskweighted light curve. Examination of the raw light curve shows no additional peaks comparable in intensity to those described above. We cannot rule out weak source activity or activity below about 50 keV. Based on the available data, T90 (15-350 keV) is 335 +- 32 sec (estimated error including systematics). The time-averaged spectrum from T-62.6 to T+298.7 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.75 +- 0.20. The fluence in the 15-150 keV band is 3.3 +- 0.4 x 10-6 erg/cm2. The 1-sec peak photon flux measured from T+20.73 sec in the 15-150 keV band is 1.5 +- 0.3 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/351525/BA/ //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 9366 SUBJECT: GRB 090509: Fermi GBM observation DATE: 09/05/15 15:33:09 GMT FROM: Andreas von Kienlin at MPE A. von Kienlin (MPE) and Sheila McBreen (UCD/MPE) report on behalf of the Fermi GBM Team: "At 05:10:05.72 UT on 09 May 2009, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 090509 (trigger 263538607 / 090509215) which was also detected by the SWIFT-BAT (Grupe et al. 2008, GCN 9325; Krimm et al., GCN 9349). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight is 75 degrees. The GBM light curve consists of two widely separated multi-peaked emission periods with a duration (T90) of about 295 s (8-1000 keV). The time-averaged spectrum of the first emission complex from T0-3.072 to T0+24.576 s is well fit by a power law function with an exponential high energy cutoff. The power law index is -0.90 +/- 0.16 and the cutoff energy, parameterized as Epeak, is 343 +/- 93 keV (chi squared 375 for 360 d.o.f.). The time-averaged spectrum of the second emission complex from T0+239.619 s to T0+288.772 s is best fit by a simple power law function with index -1.55 +/- 0.07 (chi squared 328 for 361 d.o.f.). The summed event fluence (8-1000 keV) of both time intervals is (8.4 +/- 0.4)E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0+18.432 s in the 8-1000 keV band is 3.1 +/- 0.3 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."