GRB090424A

This page lists all entries on GRB090424A in GRBweb

Summary Fermi GBM IPN Swift GCN 9223 GCN 9224 GCN 9225 GCN 9226 GCN 9230 GCN 9231 GCN 9232 GCN 9233 GCN 9234 GCN 9236 GCN 9237 GCN 9238 GCN 9239 GCN 9240 GCN 9243 GCN 9245 GCN 9246 GCN 9247 GCN 9248 GCN 9250 GCN 9252 GCN 9253 GCN 9260 GCN 9270 GCN 9275 GCN 9278 GCN 9305 GCN 9313 GCN 9316 GCN 9320 GCN 9484 GCN 9504 GCN 11883 GCN 11884

Summary table
Variable Value Source
GRB_name_Fermi GRB090424592
T0 14:08:12.670 UTC GCN_circulars,Fermi GBM Det
ra 189.5213° Swift
decl 16.8375° Swift
pos_error 9.58e-05° Swift
T90 14.144 s Fermi_GBM
T90_error 0.264 s Fermi_GBM
T90_start 14:12:09.177 UTC Fermi_GBM
fluence 4.63e-05 erg/cm² Fermi_GBM
fluence_error 3.86e-08 erg/cm² Fermi_GBM
redshift 0.5440 GCN_circulars,Other
T100 284.33 s
GBM_located False
mjd 54945.58903553241 GCN_circulars,Fermi GBM Det
Fermi GBM table
GRB_name_Fermi GRB090424592
trigger_name bn090424592
ra 189.5000°
decl 16.8000°
pos_error 2.51e+00°
datum 2009-04-24
t_trigger 14:12:08.665 UTC
T90 14.144 s
T90_error 0.264 s
T90_start 14:12:09.177 UTC
fluence 4.63e-05 erg/cm²
fluence_error 3.86e-08 erg/cm²
flux_1024 1.10e+02 erg/cm²/s
flux_1024_error 4.90e-01 erg/cm²/s
flux_1024_time 5.12e-01 erg/cm²/s
flux_64 1.27e+02 erg/cm²/s
flux_64_error 2.04e+00 erg/cm²/s
IPN table
GRB_name GRB090424A
ra 189.5375°
decl 16.8333°
pos_error 5.00e-02°
redshift 0.5440
Swift table
GRB_name GRB090424A
t_trigger 14:12:09 UTC
ra 189.5213°
decl 16.8375°
pos_error 9.58e-05°
T90 48.0 s
fluence 2.10e-05 erg/cm²
redshift 0.5440
GCN 9223 table
GRB_name GRB090424A
GCN_number 9223
Detection_method Swift Det
t_trigger 14:12:09 UTC
ra 189.5380°
decl 16.8290°
Circular_text TITLE: GCN CIRCULAR NUMBER: 9223 SUBJECT: GRB 090424: Swift detection of a burst with an optical counterpart DATE: 09/04/24 14:23:57 GMT FROM: Scott Barthelmy at NASA/GSFC J. K. Cannizzo (NASA/UMBC), S. D. Barthelmy (GSFC), A. P. Beardmore (U Leicester), D. N. Burrows (PSU), P.A. Curran (MSSL-UCL), P. A. Evans (U Leicester), N. Gehrels (NASA/GSFC), C. Gronwall (PSU), C. Guidorzi (U Ferrara), S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU), H. A. Krimm (CRESST/GSFC/USRA), J. Mao (INAF-OAB), R. Margutti (Univ Bicocca&OAB), F. E. Marshall (NASA/GSFC), P. T. O'Brien (U Leicester), K. L. Page (U Leicester), P. Romano (INAF-IASFPA), B. A. Rowlinson (U Leicester), M. H. Siegel (PSU), M. C. Stroh (PSU), G. Tagliaferri (INAF-OAB) and L. Vetere (PSU) report on behalf of the Swift Team: At 14:12:09 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 090424 (trigger=350311). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 189.538, +16.829 which is RA(J2000) = 12h 38m 09s Dec(J2000) = +16d 49' 46" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows several bright peaks in the first 5 seconds, and then several smaller peaks at T+8, +15, and +50 sec. Total duration of about 60 sec. The peak count rate was ~50000 counts/sec (15-350 keV), at ~3 sec after the trigger. The XRT began observing the field at 14:13:33.8 UT, 84.5 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 189.5213, +16.8364 which is equivalent to: RA(J2000) = 12h 38m 05.11s Dec(J2000) = +16d 50' 11.0" with an uncertainty of 4.8 arcseconds (radius, 90% containment). This location is 63 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 91 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at RA(J2000) = 12:38:05.11 = 189.52128 DEC(J2000) = +16:50:15.1 = 16.83753 with a 90%-confidence error radius of about 0.74 arc sec. This position is 4.1 arc sec. from the center of the XRT error circle. The estimated magnitude is 15.29 with a 1-sigma error of about 0.14. No correction has been made for the expected extinction corresponding to E(B-V) of 0.03. Burst Advocate for this burst is J. K. Cannizzo (cannizzo 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.)
GCN 9224 table
GRB_name GRB090424A
GCN_number 9224
Detection_method Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 9224 SUBJECT: GRB 090424: ROTSE-III Confimation of Optical Counterpart DATE: 09/04/24 14:35:53 GMT FROM: Fang Yuan at ROTSE F. Yuan (U Mich), report on behalf of the ROTSE collaboration: ROTSE-IIIa, located at Siding Spring Observatory, Australia, responded to GRB 090424 (Swift trigger 350311;Cannizzo et al, GCN 9223). The first image started at 14:18:41.4 UT, ~6 min after the burst. The unfiltered images are calibrated relative to USNO A2.0. We detect a fading source at the position consistent with the UVOT OT, at the following magnitude: start UT mag mlim(of image) ---------------------------------- 14:18:41.4 15.5 17.2 This source is not visible in DSS (second epoch), 2MASS or the MPChecker database. A jpeg image is available at http://www.rotse.net/images/gsb350311_3a001-010_key.jpg Note that the object marked 12 is the candidate in question. Continuing observations are in progress.
GCN 9225 table
GRB_name GRB090424A
GCN_number 9225
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 9225 SUBJECT: GRB 090424: TNT optical observations DATE: 09/04/24 15:21:45 GMT FROM: W.K. Zheng at NAOC L.P. Xin, W.K. Zheng, Y.L. Qiu, J.Y. Wei, j. Wang, J.S. Deng, Y. Urata and J.Y. Hu on behalf of EAFON report: TNT quickly responsed to the GRB 090424 (Swift trigger 350311; Cannizzo et al. GCN 9223) in automatical mode, the first images was taken start 14:13:36, 87s after the burst. The optical afterglow (Cannizzo et al. GCN 9223; Yuan GCN 9224) was clearly detected in our early white and R bands images, after preliminary reduction, we estimated the afterglow have faded about 3.5 mag from ~100s to ~1000s after the burst. Observation is still under going. This message may be cited.
GCN 9226 table
GRB_name GRB090424A
GCN_number 9226
Detection_method Swift Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 9226 SUBJECT: GRB 090424: SDSS Galaxy at the Swift position DATE: 09/04/24 15:23:49 GMT FROM: Phil Evans at U of Leicester P.A. Evans (U. Leicester) and S.T. Holland (CRESST/USRA/GSFC) report: We note the presence of the extended source SDSS J123805.09+165014.6 in the UVOT error circle of GRB 090424 (Cannizzo et al. GCN Circ 9223); 0.1" away from the Swift-UVOT position. This potential host galaxy has a photo-z of 0.26. GRB 090424 was detected in the u-band by Swift/UVOT, which is consistent with a low redshift origin of the burst.
GCN 9230 table
GRB_name GRB090424A
GCN_number 9230
Detection_method Fermi GBM Det
t_trigger 14:08:12.670 UTC
Circular_text TITLE: GCN CIRCULAR NUMBER: 9230 SUBJECT: GRB 090424: Fermi GBM Observation DATE: 09/04/24 17:46:24 GMT FROM: Valerie Connaughton at MSFC Valerie Connaughton (UAH) reports on behalf of the Fermi GBM Team: "At 14:08:12.67 UT on 24 April 2009, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 090424 (trigger 262275130 / 090424592). which was also detected by the Swift-BAT (J. Cannizzo et al. 2009, GCN 9223). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight is 71 degrees, increasing after trigger time. The GBM light curve shows an intense, multi-peaked emission period lasting around 6 sec, tailing off into smaller peaks until about 20 sec after trigger time, followed by a smaller peak between 45-60 sec after the trigger. The duration (T90) between 8 and 1000 keV is about 52 sec. The time-averaged spectrum of the peak from T0-0.3 s to T0+5.5 s is best fit by a Band function with Epeak = 177 +/- 3 keV, alpha = 0.90 +/- 0.02, and beta = -2.9 +/- 0.1 The event fluence (8-1000 keV) over the entire event (-0.3 s to 59 s) is (5.2 +/- 0.1)E-05 erg/cm^2. The 0.128-sec peak photon flux measured at 1.4 s in the 8-1000 keV band is 137 +/- 5 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN 9231 table
GRB_name GRB090424A
GCN_number 9231
Detection_method Swift-BAT Det
ra 189.5310°
decl 16.8290°
Circular_text TITLE: GCN CIRCULAR NUMBER: 9231 SUBJECT: GRB 090424: Swift-BAT refined analysis DATE: 09/04/24 19:20:50 GMT FROM: Scott Barthelmy at NASA/GSFC T. Sakamoto (GSFC/UMBC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. K. Cannizzo (NASA/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), 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 090424 (trigger #350311) (Cannizzo, et al., GCN Circ. 9223). The BAT ground-calculated position is RA, Dec = 189.531, 16.829 deg which is RA(J2000) = 12h 38m 07.4s Dec(J2000) = +16d 49' 45.9" with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 12%. The mask-weighted light curve shows several overlapping bright peaks starting at about T-2sec and ending at about T+5 sec. There are 3 much weaker, and broader, peaks at T+7, +15, and +50 sec. The emission returns to background at around T+150 sec. T90 (15-350 keV) is 48 +- 3 sec (estimated error including systematics). The time-averaged spectrum from T-0.7 to T+103.2 sec is best fit by a power law with an exponential cutoff. This fit gives a photon index 1.19 +- 0.15, and Epeak of 108.6 +- 20.3 keV (chi squared 45.8 for 56 d.o.f.). For this model the total fluence in the 15-150 keV band is 2.1 +- 0.0 x 10^-5 erg/cm2 and the 1-sec peak flux measured from T-0.10 sec in the 15-150 keV band is 71.0 +- 2.0 ph/cm2/sec. A fit to a simple power law gives a photon index of 1.62 +- 0.03 (chi squared 72.0 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/350311/BA/
GCN 9232 table
GRB_name GRB090424A
GCN_number 9232
Detection_method Swift-XRT Det
ra 189.5211°
decl 16.8377°
Circular_text TITLE: GCN CIRCULAR NUMBER: 9232 SUBJECT: GRB 090424: Enhanced Swift-XRT position DATE: 09/04/24 19:40:43 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 564 s of XRT Photon Counting mode data and 2 UVOT images for GRB 090424, 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 = 189.52107, +16.83773 which is equivalent to: RA (J2000): 12h 38m 5.06s Dec (J2000): +16d 50' 15.8" with an uncertainty of 1.7 arcsec (radius, 90% confidence). This position may be improved as more data are received. The latest position can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, arXiv:0812.3662). This circular was automatically generated, and is an official product of the Swift-XRT team.
GCN 9233 table
GRB_name GRB090424A
GCN_number 9233
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 9233 SUBJECT: GRB 090424: MASTER-Net prompt optical observations DATE: 09/04/24 21:01:23 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs E. Gorbovskoy, V. Lipunov, V.Kornilov, A.Belinski, N.Shatskiy, N.Tyurina, D.Kuvshinov, P.Balanutsa, V.V.Chazov, P.V.Kortunov, A.Kuznetsov Sternberg Astronomical Institute, Moscow State University K.Ivanov, S.Yazev Irkutsk State University A. Tlatov, A.V. Parhomenko, Kislovodsk Solar Station of the Pulkovo Observatory V.Krushinski, I.Zalognikh, T.Kopytova Ural State University, Kourovka There are 6 MASTER Very Wide Field cameras located at Kislovodsk and Irkutsk with common FOW = 6000 square degrees (http://observ.pereplet.ru/). One of the two MASTER Very Wide Field Cameras located at Irkutsk (D=50 mm, 2x1000 square degrees, 11 Mpx, 72" per pix in binning regime) has observed UVOT error box (Cannizzo et al., GCN 9223) with 1s exposure befoure, during and after GRB Time without time gap between images. The error box is near at the center of our FOW. Our unfiltered images are calibrated relative to Tycho stars (V). The magnitude limit of the each emage is ~8 m at the center of FOW (some cloudy on the sky). The limit of coadded five images ~ 9 m. The reduction is continued. The message may be cited. mailto: lipunov@sai.msu.ru
GCN 9234 table
GRB_name GRB090424A
GCN_number 9234
Detection_method Swift-UVOT Det
Circular_text TITLE: GCN CIRCULAR NUMBER: 9234 SUBJECT: Swift/UVOT observations of GRB 090424 DATE: 09/04/24 21:42:37 GMT FROM: Samantha Oates at MSSL P.Schady (MSSL/UCL) and J. K. Cannizzo (NASA/UMBC) report on behalf of the Swift/UVOT team: The Swift/UVOT started settled observations of the burst GRB090424 (Cannizzo et al. GCN Circ. 9223) with the finding chart (fc) exposure in white, 167s after the BAT trigger. The afterglow is detected in the all filters at the position reported by Cannizzo et al. (GCN Circ. 9223), placing an upper limit on the redshift of ~1.3. The combined UVOT data indicates that the afterglow is fading with a decay index of alpha ~ 0.9. The UVOT magnitudes our reported below: Filter Tmid(s) Exp(s) Magnitude white (fc) 167 147.4 15.27 +/- 0.01 u (fc) 429 245.8 16.40 +/- 0.03 white 594 19.4 16.99 +/- 0.07 v 644 19.5 16.86 +/- 0.19 b 570 19.5 17.27 +/- 0.13 u 1122 19.5 17.44 +/- 0.20 uvw1 695 19.5 16.81 +/- 0.19 uvm2 670 19.4 17.39 +/- 0.34 uvw2 793 19.4 17.51 +/- 0.27 The values quoted above are in the UVOT photometric system (Poole et al. 2008, MNRAS, 383, 627) and are not corrected for the expected Galactic extinction corresponding to a reddening of E(B-V)=0.025 mag in the direction of the burst (Schlegel et al. 1998).
GCN 9236 table
GRB_name GRB090424A
GCN_number 9236
Detection_method Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 9236 SUBJECT: GRB 090424: Optical observations from 1.23m CAHA DATE: 09/04/24 22:59:07 GMT FROM: Javier Gorosabel at IAA-CSIC J. Gorosabel, P. Kubanek , M. Jelinek (IAA-CSIC), A. de Ugarte Postigo (ESO), J. Aceituno (CAHA), report on behalf of a larger collaboration: We have observed the field of GRB 090424 (Cannizzo et al., GCN 9223) with the 1.23m telescope at Calar Alto. The afterglow is clearly detected in BVRI-bands. On April 24.87 UT the afterglow showed a magnitude of R = 19.3 +/- 0.1, as compared to stars from the USNO-B1.0. Calar Alto is operated jointly by MPIA and IAA-CSIC. Further observations are ongoing.
GCN 9237 table
GRB_name GRB090424A
GCN_number 9237
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 9237 SUBJECT: GRB 090424: Swift-XRT refined analysis DATE: 09/04/24 23:15:47 GMT FROM: Raffaella Margutti at U. di Milano Bicocca R. Margutti (Univ. Bicocca & INAF-OAB), C. Guidorzi (Univ. Ferrara), J. Mao (INAF-OAB) and J. K. Cannizzo (NASA/UMBC) report on behalf of the Swift-XRT team: We have analysed the first 2 orbits of Swift-XRT data obtained for GRB 090424 (Cannizzo et al. GCN Circ. 9223), covering 1732 s of Windowed Timing (WT) and 1329 s of Photon Counting (PC) mode data, respectively, between 88 s and 8 ks after the trigger. The UVOT-enhanced XRT position was given by Goad et al. in GCN Circ. 9232. The light-curve can be modelled by a double broken power-law, with a first decaying index alpha_1= 1.29 +/- 0.05 and a first break time of about 260 s. The decay then flattens to alpha_2= 0.74 +/- 0.02. After 1450 s the decay is best modelled by a power-law index alpha_3= 1.15 +/- 0.05. The very good statistics allows us to observe spectral evolution in WT data before the first break, with the simple power law photon index evolving from 2.6 to 2.1 . A spectrum extracted from WT mode data in the time interval 0.4-1.4 ks can be modelled with an absorbed power-law with a photon index Gamma= 2.13 +/- 0.05 and best-fitting absorption column NH = (0.20 +/- 0.01) x10^22 cm^-2, in excess of the Galactic value of 1.9 x 10^20 cm^-2 (Kalberla et al. 2005). The spectrum extracted from PC data in the time interval 6.1-8 ks can be modelled with an absorbed power-law, with Gamma = 2.06 +/- 0.09 and a column density of NH = (0.27 +/- 0.03)x10^22 cm^-2. The observed (unabsorbed) 0.3 -10 keV flux over this time interval is 4.2x10^-11 (6.7x10^-11) erg cm^-2 count^-1. Uncertainties are given at 90% confidence. If the light-curve continues to decay with alpha ~1.15, the count rate 24 hours after the burst is estimated to be 0.10 count s^-1, which corresponds to an observed (unabsorbed) flux of 4.2x10^-12 (6.7x10^-12) erg cm^-2 s^-1. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00350311. This circular is an official product of the Swift-XRT team.
GCN 9238 table
GRB_name GRB090424A
GCN_number 9238
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 9238 SUBJECT: GRB 090424: Liverpool Telescope observations DATE: 09/04/24 23:24:58 GMT FROM: Cristiano Guidorzi at Ferrara U,Italy C. Guidorzi (U. Ferrara), D. Bersier (Liverpool JMU), and N. Tanvir (U. Leicester) on behalf of a larger collaboration report: We began observing the field of GRB 090424 (Cannizzo et al. GCN Circ. 9223) with the 2-m Liverpool Telescope at 21:29:47 UT. We clearly detect the optical afterglow (Cannizzo et al. GCN Circ 9223; Yuan et al. GCN Circ. 9224; Xin et al. GCN Circ. 9225; Schady et al. GCN Circ. 9234; Gorosabel et al. GCN Circ. 9236) with r'=19.93 0.03 at a mid epoch of 7.55 hrs post burst from a 6x300 s coadded exposure. Calibration was performed with respect to nearby SDSS field stars.
GCN 9239 table
GRB_name GRB090424A
GCN_number 9239
Detection_method Optical
ra 189.5213°
decl 16.8376°
Circular_text TITLE: GCN CIRCULAR NUMBER: 9239 SUBJECT: GRB 090424 optical observations DATE: 09/04/24 23:40:52 GMT FROM: AAVSO GRB Network at AAVSO Arto Oksanen (Hankasalmi Obs., Hankasalmi, Finland) reports via the AAVSO International High Energy Network the following optical observations of GRB 090424 (Cannizzo et al., GCN #9223): A. Oksanen reports the detection of the optical counterpart of GRB 090424 approximately 6.5 hours post-burst. Unfiltered observations were made using a 0.4-meter RC telescope with an SBIG STL-1001E CCD. A total of sixty, 60-second observations were made having a mid-point time of 20:45:00 UT on 2009 April 24. The afterglow was detected with a magnitude of 19.1 +/- 0.1 measured relative to the R band magnitude of USNO-A2.0 1050-06753889 (R=16.3). Astrometry of the afterglow position yields a position of RA: 12h 38m 05.1s, Dec: +16d 50m 15.3s, in agreement with the UVOT coordinates given by Cannizzo et al. (GCN #9223). A jpeg preview of the observation showing the position of the afterglow is available at this URL: http://murtoinen.dyndns.org:8888/ccd/grb/GRB090424/GRB090424-S001-R0XX-Clear.jpg A detailed report of the observation is available at the following URL: ftp://ftp.aavso.org/grb/ArtoOksanen_GRB090424_2454946.42162_.txt A FITS image of this observation is available at the following URL: ftp://ftp.aavso.org/grb/ArtoOksanen_GRB090424_2454946.42162_.fits The AAVSO thanks the Curry Foundation for their continued support of the AAVSO International High Energy Network.
GCN 9240 table
GRB_name GRB090424A
GCN_number 9240
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 9240 SUBJECT: GRB 090424 : TAOS optical detection DATE: 09/04/25 01:27:48 GMT FROM: Kuiyun Huang at ASIAA GRB 090424 : TAOS optical detection Y. Urata, Z.W. Zhang, C.Y. Wen, K.Y. Huang, S.Y. Wang and the TAOS team Three 50cm TAOS telescopes, located at Lulin observatory, Taiwan, started to observe GRB 090424 field (Cannizzo et al.; GCN 9223) at 94s after the trigger. The optical afterglow (Yuan et al., GCN 9224; Xin et al. GCN 9225) was clearly detected in images taken by TAOSA (25s exposure), TAOSB (5s exposure), and TAOSD (1s exposure). Brightness of the afterglow is about R~13.08 at 94s post the burst. Our R-band magnitude were calibrated with USNOB red stars. this message can be cited
GCN 9243 table
GRB_name GRB090424A
GCN_number 9243
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 9243 SUBJECT: GRB 090424 Gemini-South Redshift DATE: 09/04/25 03:02:24 GMT FROM: Ryan Chornock at UC Berkeley R. Chornock, D. A. Perley, S. B. Cenko, and J. S. Bloom (UC Berkeley) report on behalf of a larger collaboration: We obtained optical spectra of the afterglow of GRB 090424 (Cannizzo et al., GCN 9223) using GMOS on Gemini-South. Our spectra cover the wavelength range of 4400-8600 angstroms. Our first 1200s exposure, starting at 01:51:56 April 25 UT (11.7 hr after the trigger) reveals.a pair of absorption lines at 6077 and 6130 Angs, which we identify as the Ca II H+K doublet at z=0.544. Additionally, an emission line is present at 5758 A, which is consistent with the [O II] 3727 doublet at the same redshift, which we therefore identify as the redshift of the host galaxy. We note that this redshift is significantly higher than the photo-z noted by Evans & Holland (GCN 9226).
GCN 9245 table
GRB_name GRB090424A
GCN_number 9245
Detection_method GROND
Circular_text TITLE: GCN CIRCULAR NUMBER: 9245 SUBJECT: GRB 090424: GROND Observations of the Optical/NIR Afterglow DATE: 09/04/25 04:34:34 GMT FROM: Aybuke Kupcu Yoldas at ESO F. Olivares (MPE Garching), A. Kupcu Yoldas (ESO), J. Greiner, A. Yoldas (both MPE Garching) report on behalf of the GROND team: We observed the field of GRB 090424 (Swift trigger 350311;Cannizzo et al., GCN #9223) 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 02:52 UT on 25 April, ~12.5 hours after the GRB trigger, and are continuing. They were performed at an average seeing of 1.0 and at an average airmass of 1.45. We clearly detect the optical afterglow (Cannizzo et al. GCN #9223; Yuan et al. GCN #9224; Xin et al. GCN #9225; Schady et al. #9234; Gorosabel et al. GCN #9236). Preliminary photometry yields the following AB magnitudes in stacked images of the first OB, obtained using SDSS/2MASS stars as reference: Filter Exp[s] AB Mag MagErr ---------------------------------------- g' 4x115 20.98 0.02 r' 4x115 20.42 0.04 i' 4x115 20.01 0.04 z' 4x115 19.64 0.02 J 48x10 19.08 0.09 H 48x10 18.62 0.03 K 48x10 18.29 0.04 Given magnitudes are not corrected for the expected Galactic foreground extinction corresponding of E_(B-V)=0.03 mag (Schlegel et al. 1998). These magnitudes combined with the results of previous observations (Schady et al. GCN #9234, Guidorzi et al. GCN #9238) indicate a flattening in the afterglow light-curve.
GCN 9246 table
GRB_name GRB090424A
GCN_number 9246
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 9246 SUBJECT: GRB 090424: THO optical observations DATE: 09/04/25 05:35:50 GMT FROM: Veli-Pekka Hentunen at Taurus Hill Obs,A95 Markku Nissinen (Taurus Hill Observatory) and Veli-Pekka Hentunen (Taurus Hill Observatory) report: We used 0.35m C14 XLT telescope with SBIG ST-8XME CCD at Taurus Hill Observatory (Varkaus, Finland) for follow-up observations of GRB090424. The observations were started on April 24, at 19:59 UTC (5.8 hours after the burst) and stopped on April 24, at 23:11 UTC. Sixteen unfiltered 600 seconds images were taken. We detected clear optical afterglow object at the position of RA 12h 38m 05s.12 and DEC +16o 50' 15".2 with respect to POSSII F/USNO-B1.0 which is in good correlation with enhanced Swift XRT-UVOT position. Upper limit for the observations is >20.4 mag. Quoted upper limit has been derived using POSSII F and USNO-B1.0 field stars as reference. Filter Tmid(s) Exp(s) Mag (CR) USNO-B1.0 u 20:14:23 600 19.55+/-0.37 u 20:37:30 600 19.95+/-0.38 u 21:32:48 600 20.15+/-0.34 A jpeg preview of the observation showing the position of the afterglow is available at this URL: http://cutenews.kassiopeia.net/data/upimages/grb090424_ticks.jpg
GCN 9247 table
GRB_name GRB090424A
GCN_number 9247
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 9247 SUBJECT: GRB 090424 : Lulin 1m telescope optical observations DATE: 09/04/25 06:06:14 GMT FROM: Yuji Urata at Nat. Central U. Y. Urata(NCU), K. Y. Huang (ASIAA) on behalf of EAFON report; "We have observed optical afterglow of GRB090424 (Cannizzo et al., GCN #9223, Yuan et al. GCN #9224; Xin et al. GCN #9225; Schady et al. #9234; Gorosabel et al. GCN #9236; Urata et al. GCN #9240, Olivares et al GCN #9245; Nissinen et al. GCN #9246) using Lulin 1m telescope (LOT) with B, V, R, I and z'-band filters. Observations started at 14:34:18 UT on 24 April. These LOT images show the afterglow clearly. Based on our preliminary photometry compared with USNO B1.0 stars, the R-band light curve between 1329 sec and 13303 sec after the burst is well fitted by a simple power law with the decay index 0.71."
GCN 9248 table
GRB_name GRB090424A
GCN_number 9248
Detection_method Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 9248 SUBJECT: GRB090424: BVRI/R-band detection after 15 hrs burst DATE: 09/04/25 06:52:02 GMT FROM: Myungshin Im at Seoul Nat U M. Im, W. Park, Y. Jeon, I. Lee (CEOU/Seoul National Univ), Y.-B. Jeon (KASI) and Y. Urata (NCU) on behalf of EAFON team. We took BVRI-band images of GRB090424 (GCN 9223) using the 1.0m telescope at Mt. Lemmon (Arizona, US) operated by the Korea Astronomy Space Science Institute. The whole sequence of the observation started at 2009 April 25, 04:30:19 UT, among which R-band observation started at 04:58:32.22. From a stacked image of 6 frames (3 min exp. each), we cleary detect the afterglow at R=19.9 +- 0.14 mag, calibrated against USNO-B1 stars in the vicinity. The mid-point of the obseravation is April 25, 05:10:57 UT (14.97 hrs after the burst). Analysis of the BVI data is ongoing. We thank the LOAO operator, J. Yoon for his assistance for this observation.
GCN 9250 table
GRB_name GRB090424A
GCN_number 9250
Detection_method Other
redshift 0.5440
Circular_text TITLE: GCN CIRCULAR NUMBER: 9250 SUBJECT: GRB 090424: WHT ISIS spectroscopy DATE: 09/04/25 17:23:03 GMT FROM: Klaas Wiersema at U of Leicester K. Wiersema (Leicester), A. de Ugarte Postigo (ESO) and A. Levan (Warwick) report on behalf of a larger collaboration: We observed the afterglow of GRB 090424 (Cannizzo et al, GCN 9223) with the ISIS spectrograph on the William Herschel Telescope at the Observatorio del Roque de los Muchachos on La Palma, ~8 hours after burst. In the spectrum we find several lines, among others the Mg II doublet (with restframe EW > 1 A of the 2796 line), Fe II, Na I. Through these we confirm the redshift of z=0.544 found by Chornock et al (GCN 9243). Continuum is detected up to at least 3200 A, giving an upper limit to the GRB redshift of 1.6, consistent with the emission and absorption redshift of 0.544. We thank the staff of the WHT, in particular O. Vadivescu, for support for these observations.
GCN 9252 table
GRB_name GRB090424A
GCN_number 9252
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 9252 SUBJECT: GRB 090424: MASTER-Net prompt optical limit DATE: 09/04/25 20:29:42 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs E. Gorbovskoy, V. Lipunov, V.Kornilov, A.Belinski, N.Shatskiy, N.Tyurina, D.Kuvshinov, P.Balanutsa, V.V.Chazov, P.V.Kortunov, A.Kuznetsov Sternberg Astronomical Institute, Moscow State University K.Ivanov, S.Yazev Irkutsk State University A. Tlatov, A.V. Parhomenko, Kislovodsk Solar Station of the Pulkovo Observatory V.Krushinski, I.Zalognikh, T.Kopytova Ural State University, Kourovka There are 6 MASTER Very Wide Field cameras located at Kislovodsk and Irkutsk with common FOW = 6000 square degrees (http://observ.pereplet.ru/). One of the two MASTER Very Wide Field Cameras located at Irkutsk (D=50 mm, 2x1000 square degrees, 11 Mpx, 72" per pix in binning regime) has observed UVOT error box (Cannizzo et al., GCN 9223) with 1s exposure befoure, during and after GRB Time without time gap between images. The error box is near at the center of our FOW. Our unfiltered images are calibrated relative to Tycho stars (V) and very close to V band. The magnitude limit of the each emage is ~8 m at the center of FOW (some cloudy on the sky). The limit of coadded six images ~ 9 m. We do not detect OT. Our observations results: ---------------------------------------------------------------------- Fermi GRB Trigg.* Exposure Mag Limit Optical Flux Coadd? time (sec) (sec) (m) (erg/sm^2 s) ---------------------------------------------------------------------- -2 1 8.1 1.3x10^-8 No -1 1 8.1 1.3x10^-8 No 0 1 8.0 1.4x10^-8 No +1 1 8.0 1.4x10^-8 No +2 1 8.0 1.4x10^-8 No +3 1 7.9 1.5x10^-8 No +4 1 8.0 1.4x10^-8 No +5 1 8.0 1.4x10^-8 No -60 : +120 1 ~8 ~1.4x10^-8 No -6 6 8.9 7.0x10^-9 Yes +0 6 8.7 7.3x10^-9 Yes +6 6 8.8 7.2x10^-9 Yes +12 6 8.9 7.0x10^-9 Yes -60 60 9.7 3.0x10^-9 Yes 0 60 9.7 3.0x10^-9 Yes 60 60 9.5 3.5x10^-9 Yes ----------------------------------------------------------------------- *Fermi GBM Trigger Time = 14:12:08.67 (Connaughton, GCN 9230) 1% coincident with our start zero image time. 1). the optical fluence during GRBurst is limited by 0 up to +6 s ~<= 1 x 10E-7 erg/cm^2 0 up to +60 s <= 5 x 10E-7 erg/cm^2 including total absorbtion 1 magnitude in V band. (The absorption column density NH = (0.20 +/- 0.01) x10^22 cm^-2 from Swift XRT spectrum data, Margutti, GCN 9237). The event fluence (8-1000 keV) in this time interval is (5.2 +/- 0.1)E-05 erg/cm^2 (Connaughton, GCN 9230). So: 2). Optical-Fluence(6s)/Gamma-Fluence (8-1000 keV) ~ < 1/500 Optical-Fluence(60s)/Gamma-Fluence(8-1000 keV) ~ < 1/100 The same ratio for GRB080319B is Optical-Fluence/Gamma-Fluence(8 - 1000 keV) ~ 1/140 (Naked Eye GRB, Racusin, Karpov et al., Nature, vol.455, 183, 2008). The light curve and film of our observations is available at http://observ.pereplet.ru/images/GRB090424/GRB090424.html The reduction is continued. The message may be cited. mailto: lipunov@sai.msu.ru
GCN 9253 table
GRB_name GRB090424A
GCN_number 9253
Detection_method Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 9253 SUBJECT: GRB090424: R-band detection (37.5 hrs post-burst), jet break? DATE: 09/04/26 11:30:29 GMT FROM: Myungshin Im at Seoul Nat U M. Im, W. Park, Y. Jeon, I. Lee (CEOU/Seoul National Univ), Y.-B. Jeon (KASI) and Y. Urata (NCU) on behalf of EAFON team. We continued the follow-up observation of GRB090424 (Cannizzo et al. GCN 9223) in BVR using the 1.0m telescope at Mt. Lemmon (Arizona, US) operated by the Korea Astronomy Space Science Institute. The R-band imaging started at 2009 April 26, 03:11:23 UT. The mid-point of the R-band obseravation is April 26, 03:39:43 UT (37.45 hrs after the burst). From a stacked image of 13 frames (3 min exp. each), the afterglow is visible at R=20.96 +- 0.17 mag, suggesting a significant fading occurred since last night (Im et al. GCN 9248), more than the expected amount of fading with the power-law index of 0.71 reported earlier (Urata et al. GCN 9247). This suggests that jet break might have occured. The afterglow is also visible in B- and V-bands. The photometry was calibrated against USNO-B1 stars in the vicinity. We thank the LOAO operator, J. Yoon for his assistance for this observation.
GCN 9260 table
GRB_name GRB090424A
GCN_number 9260
Detection_method Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 9260 SUBJECT: Detection of bright radio afterglow of GRB 090424 with the VLA DATE: 09/04/26 18:29:16 GMT FROM: Poonam Chandra at U Virginia/NRAO Poonam Chandra (RMC) and Dale A. Frail (NRAO) report on behalf of a larger collaboration: "We used the Very Large Array to observe the field of view toward the GRB 090424 (GCN 9223) at a frequency of 8.46 GHz on 2009 Apr 26.09 UT. We detected a bright radio afterglow at the UVOT position (GCN 9223). The GRB radio flux density is 673 +/- 39 uJy. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc."
GCN 9270 table
GRB_name GRB090424A
GCN_number 9270
Detection_method Suzaku WAM Det
Circular_text TITLE: GCN CIRCULAR NUMBER: 9270 SUBJECT: GRB 090424: Suzaku WAM observation of the prompt emission DATE: 09/04/27 14:14:03 GMT FROM: Yoshitaka Hanabata at Hiroshima U Y. Hanabata, T. Uehara, T. Takahashi, Y. Fukazawa(Hiroshima U.), K. Kono, E. Sonoda, M. Yamauchi, N. Ohmori, H. Hayashi, K. Noda, A. Daikyuji, Y. Nishioka (Univ. of Miyazaki), M. Ohno, M. Suzuki, M. Kokubun, T. Takahashi (ISAS/JAXA), W. Iwakiri, M. Tashiro, Y. Terada, A. Endo, K. Onda, T. Sugasahara (Saitama U.), Y. Urata (NCU), T. Enoto, K. Nakazawa, K. Makishima (Univ. of Tokyo), K. Yamaoka, S. Sugita (Aoyama Gakuin U.), Y. E. Nakagawa, T. Tamagawa (RIKEN), S. Hong (Nihon U.), N. Vasquez (Tokyo Tech.), on behalf of the Suzaku WAM team, report: The long GRB 090424 (Swift/BAT trigger #350311 ; Cannizzo et al., GCN 9223) triggered the Suzaku Wide-band All-sky Monitor (WAM) which covers an energy range of 50 keV - 5 MeV at 14:12:09.216 UT (=T0). The observed light curve shows a multi-peaked structure starting at T0-1 s, ending at T0+12 s, with a duration (T90) of about 4.18 seconds. The fluence in 100 - 1000 keV was 1.36 (-0.10, +0.28) x10^-5 erg/cm2. The 1-s peak flux measured from T0 was 12.6 (-0.9, +1.6) photons/cm2/s in the same energy range. Preliminary result shows that the time-averaged spectrum from T0-1 s to T0+12 s is fitted by a power-law with exponential cutoff model: dN/dE ~ E^{-alpha} * exp(-(2-alpha)*E/Epeak) with alpha 0.92 (-0.77, +0.66), and Epeak 250 (-83, +41) keV (chi^2/d.o.f. = 18.9/27). Due to the high counting rate of this GRB, a 3% systematic error was added for low energy channels. We note that this GRB came from the WAM 2 direction, which has a large uncertainty ~40 % in the absolute flux. The light curves for this burst are available at: http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html
GCN 9275 table
GRB_name GRB090424A
GCN_number 9275
Detection_method Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 9275 SUBJECT: GRB 090424: Continued R-band monitoring DATE: 09/04/28 02:18:53 GMT FROM: Myungshin Im at Seoul Nat U M. Im, Y. Jeon, W. Park, I. Lee (CEOU/Seoul National Univ), Y.-B. Jeon (KASI) and Y. Urata (NCU) on behalf of EAFON team. We continued our follow-up observation of GRB090424 (Cannizo et al. GCN 9223) in R using the 1.0m telescope at Mt. Lemmon (Arizona, US) operated by the Korea Astronomy Space Science Institute. The R-band imaging started at 2009 April 27, 02:57:33 UT. The mid-point of the R-band obseravation is April 27, 03:45:21 UT (61.55 hrs after the burst). From a stacked image of 20 frames (3 min exp. each), we clearly detect the afterglow at R=21.7 +- 0.3 mag. Note that this value includes the flux (R ~ 22.2 mag) of the host or foreground galaxy at the location of the GRB noted by Evans et al. (GCN 9226). The trend of the fading, corrected for the galaxy light contamination, is consistent with a steep decay of flux reported earlier (Im et al. GCN 9253). The photometry was calibrated against USNO-B1 stars in the vicinity of GRB. Mid-point Rmag Rmag (hrs after burst) (excluding the galaxy light) ----------------------------------------------------- 14.97 19.9+-0.14 20.0 37.45 21.0+-0.17 21.4 61.55 21.7+-0.30 22.8 We thank the LOAO operator, I. Baek for her assistance for this observation.
GCN 9278 table
GRB_name GRB090424A
GCN_number 9278
Detection_method Swift Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 9278 SUBJECT: GRB 090424 : Multiband Optical observation from Nainital DATE: 09/04/28 19:35:04 GMT FROM: Rupak Roy at ARIES Rupak Roy, Brajesh Kumar, S. B. Pandey and Brijesh Kumar (ARIES, NainiTal, India, on behalf of larger Indian GRB collaboration). We performed BVRI photometric observation of Swift GRB 090424 (Cannizzo, J. K. et al., GCN 9223) on 24th April, 2009 at 16.7 hrs UT, under moderate sky conditions, using 1.04 m Sampurnanand Optical telescope at ARIES, Nainital. The same field was again observed on next day, about 29 hrs after the burst in R and I bands. Fading nature of the afterglow is clearly visible in all bands. The R_c and I_c band magnitudes of OT, with respect to nearby USNO-B1 stars, are 18.5 +/- 0.05 and 17.8 +/- 0.06 respectively, measured 2.67 hrs after the burst. Further analysis is under progress.
GCN 9305 table
GRB_name GRB090424A
GCN_number 9305
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 9305 SUBJECT: GRB 090424: YNAO-GMG observations DATE: 09/04/30 11:10:12 GMT FROM: Jirong Mao at Yunnan Obs J. Mao (YNAO & INAF-OAB), G. Cha and J. Bai (YNAO) report on behalf of the GMG group: We observed the optical counterpart of GRB 090424 (Cannizzo et al., GCN 9223) using one 2.4-m telescope located at Gao-Mei-Gu (GMG) about 40 minutes after the trigger and obtained the following magnitudes: Start UT Exposure Filter mag err ------------------------------------------------- 14:53:41 10 sec R 17.51 0.02 14:56:41 30 sec B 18.50 0.03 15:01:22 30 sec V 18.57 0.02 15:03:55 20 sec I 17.68 0.02 17:26:58 75 sec R 18.89 0.04 We continued our observations of GRB 090424 in R band started at 13:42:00 UT on April 25, 2009. After 20 minutes of exposure time, we obtained the magnitude R=20.59 +/- 0.07 mag. All the calibrations were processed by nearby SDSS stars. The telescope is charged by Yunnan Observatory (YNAO), Chinese Academy of Sciences. This message might be cited.
GCN 9313 table
GRB_name GRB090424A
GCN_number 9313
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 9313 SUBJECT: GRB 090424, SMARTS optical/IR afterglow monitoring DATE: 09/05/01 03:00:53 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 090424 (GCN 9223, Cannizzo et al.) over nine epochs between ~0.5 and 5.6 days post burst. In our first epoch of imaging, total summed exposure times amounted to 15 minutes in I and V and 12 minutes in J and K. All later epochs had total summed exposure times of 36 minutes in I and 30 minutes in J. The optical afterglow of GRB 090424 (e.g. GCN 9223, Cannizzo et al. & GCN 9224, Yuan et al.) is observed to fade steadily in our imaging with no indication of a jet break between ~0.5 and 5.6 days post-burst. The combined light of the afterglow and the underlying galaxy fades with a decay rate of alpha = -0.72 (where afterglow flux is proportional to t^alpha). Assuming that the galaxy has an intrinsic magnitude of I=21.6 (based on the SDSS i and r values and the Lupton 2005 transformation equations), then the afterglow's true decay rate is alpha = -1.2 over these epochs. The afterglow + host galaxy photometry is measured as follows (no correction has been made for Galactic extinction): mid-exposure time (days post-burst) I mag J mag V mag K mag ------------------------------------------------------------------- 0.45031 19.42+/-0.04 18.31+/-0.06 20.61+/-0.04 16.38+/-0.05 0.50291 19.45+/-0.04 18.11+/-0.04 ... ... 0.57498 19.61+/-0.04 18.22+/-0.05 ... ... 0.62815 19.70+/-0.04 18.23+/-0.05 ... ... 1.53459 20.45+/-0.05 19.18+/-0.08 ... ... 2.49012 20.92+/-0.05 19.61+/-0.11 ... ... 3.51877 20.99+/-0.05 19.53+/-0.09 ... ... 4.56909 21.24+/-0.08 > 19.7 ... ... 5.56135 21.31+/-0.10 > 19.7 ... ... (Optical photometry is calibrated against Landolt standard stars and IR photometry is calibrated against 2MASS stars in the field.)
GCN 9316 table
GRB_name GRB090424A
GCN_number 9316
Detection_method Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 9316 SUBJECT: ICSP VLF observation of GRB090424 from four receivers DATE: 09/05/01 13:25:00 GMT FROM: Sandip K. Chakrabarti at S.N. Bose Nat. Centre for Basic Sci. ICSP VLF observation of GRB090424 from four receivers Sandip K. Chakrabarti (S. N. Bose Centre and ICSP), Sushanta K. Mondal (ICSP), Asit Choudhury (ICSP, Malda branch), Achintya Chatterjee (ICSP, Malda Branch), Narendra N. Patra (Univ. Pune) and D. Bhowmick (ICSP) Three ICSP VLF receivers clearly observed the effects of GRB090424 (GCN#s 9223, 9230) on the ionosphere simultaneously. The subflare point (16.8d N , 123.76d E) being closer to eastern India the signal was prominent. Two receivers were kept at Kolkata (22.5N, 88.5d E) at sixteen kilometers (~ 10 miles) apart, while a third receiver was kept at Malda (25d N, 88d E) which is about 200 miles away. All the three receivers detected the GRB right after triggering and the correlation of the signals were found excellent for about ~100 seconds. Before the triggering, the correlation was poor. The signal from a fourth ICSP receiver at Pune (~1000 miles from Kolkata) in western India (18.5d N, 74d N) was very poor. A comparison of the smoothed signals can be found in allthree.jpg in http://www.bose.res.in/~chakraba/grb090424-1.html. This message may be cited.
GCN 9320 table
GRB_name GRB090424A
GCN_number 9320
Detection_method Optical
ra 12.0000°
decl 16.0000°
Circular_text TITLE: GCN CIRCULAR NUMBER: 9320 SUBJECT: GRB 090424: optical observations DATE: 09/05/04 00:21:25 GMT FROM: Alexei Pozanenko at IKI, Moscow V. Rumyantsev, K. Antoniuk (CrAO), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: We observed the afterglow (Cannizzo et al. GCN 9223; Yuan GCN 9224) of the Swift GRB 090424 (Trigger 350311; Cannizzo et al., GCN 9223) in R filter on Apr. 24 (18:25:36 -- 19:23:38) and Apr. 26 (19:57:14 -- 21:01:01) with AZT-11 telescope of CrAO. We detect the afterglow in combined images of both epochs. Astrometry of the afterglow is RA(J2000): 12 38 05.1 Dec(J2000): +16 50 14.72 with uncertainty of 0.5 arcsec. Preliminary photometry of combined images is based on USNO-B1.0 1068-0228255 star RA=12:38:02.33 Dec=+16:51:10.0 is following: T0+ Filter, Exposure, mag., err. (d) (s) 0.1972 R 20x180 19.27 +/-0.06 2.2628 R 20x180 21.0 +/-0.2 The photometry is contaminated with possible host galaxy (Evans et al. GCN 9226). The combined image of the Apr. 24 observation can de found at http://grb.rssi.ru/GRB090424/GRB090424_AZT-11_R.gif
GCN 9484 table
GRB_name GRB090424A
GCN_number 9484
Detection_method Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 9484 SUBJECT: GMRT observation of GRB 090424 afterglow DATE: 09/06/03 14:37:33 GMT FROM: Atish Kamble at U. of Amsterdam Atish Kamble (University of Amsterdam), Sabyasachi Pal (NCRA/TIFR), A. J. van der Horst (NASA/MSFC), D. Bhattacharya (IUCAA,Pune), R. Wijers (University of Amsterdam), C. H. Ishwara Chandra (NCRA/TIFR), Evert Rol (University of Amsterdam) report on behalf of a larger GRB collaboration : The Giant Metrewave Radio Telescope (GMRT), India observed the field of GRB090424 (GCN 9223, GCN 9260) on 23 May 2009 (between 11.0 UT and 15.0 UT i.e. about 30 days after the burst) at 1280 MHz using a bandwidth of 32 MHz. The radio transient was not detected down to a 3-sigma upper limit of 141 microJy at the source location. We thank the GMRT and the National Centre for Radio Astrophysics (NCRA) staff. This TOO was done under the GMRT Director's Discretionary Time. GMRT is run by NCRA-TIFR, Pune (INDIA). This message may be cited.
GCN 9504 table
GRB_name GRB090424A
GCN_number 9504
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 9504 SUBJECT: GRB 090424: WSRT Radio Observations DATE: 09/06/12 04:00:08 GMT FROM: Alexander van der Horst at NASA/MSFC A.J. van der Horst (NASA/MSFC/ORAU) and A.P. Kamble (University of Amsterdam) report on behalf of a large collaboration: "We observed the position of the GRB 090424 afterglow with the Westerbork Synthesis Radio Telescope at 2.3 GHz at May 4 19.91 UT to May 5 3.34 UT, and at 4.9 GHz at May 23 15.97 to 21.45 UT, i.e. 10.39 and 29.19 days after the burst (GCN 9223) respectively. We do not detect a radio source at the position of the optical counterpart (GCN 9223). The three-sigma rms noise in the map around that position is 168 microJy per beam at 2.3 GHz and 132 microJy per beam at 4.9 GHz. The formal flux measurement for a point source at the position of the optical counterpart is 47 +/- 56 microJy and 84 +/- 43 microJy at 2.3 and 4.9 GHz respectively. We would like to thank the WSRT staff for scheduling and obtaining these observations."
GCN 11883 table
GRB_name GRB090424A
GCN_number 11883
Detection_method Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 11883 SUBJECT: Comparison of ICSP VLF observation of GRB 090424 with satellite observations DATE: 11/04/05 11:09:52 GMT FROM: Sandip K. Chakrabarti at S.N. Bose Nat. Centre for Basic Sci. Sushanta K. Mondal (ICSP), Sandip K. Chakrabarti (S. N. Bose Centre and ICSP), Asit Choudhury (ICSP, Malda branch), Achintya Chatterjee (ICSP, Malda Branch), and D. Bhowmick (ICSP) Indian Centre for Space Physics observed the ionospheric perturbation due to GRB 090424 (GCN No. 9316) through monitoring VLF signals from various transmitters. The final analysis with corrected time stamp (http://www.bose.res.in/~chakraba/grb090424.html) suggests that VLF signals were spreaded out for few seconds due to ionospheric effects.
GCN 11884 table
GRB_name GRB090424A
GCN_number 11884
Detection_method Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 11884 SUBJECT: ICSP VLF observation of multiple SGR-like bursts from 1E 1841-045 on Feb. 9, 2011 DATE: 11/04/05 12:30:16 GMT FROM: Sandip K. Chakrabarti at S.N. Bose Nat. Centre for Basic Sci. ICSP VLF observation of multiple SGR-like bursts from 1E 1841-045 on Feb. 9, 2011 Sushanta K. Mondal (ICSP), Sandip K. Chakrabarti (S. N. Bose Centre and ICSP), Debashis Bhowmick (ICSP) We observed several sudden ionospheric disturbances on Feb. 9th, 2011 in signals transmitted from several stations. One of them (occurring at 05:14:26 UT) coincided exactly with the observed time of Fermi (GCN #11684) but there were many both before and after within a few hundred seconds. All these events were observed in both phase and amplitude, indicating that the disturbances were real. One image of the amplitude/phase from various transmitting stations as obtained by our receiver at Sitapur station is in http://www.bose.res.in/~chakraba/gbm090211.html. The entire set of events were riding on a 'B' type flare, but we suspect our events are not parts of any solar flare, as the time durations of the signals involved appear to be too short (similar to our GRB090424 for our VLF signal; see GCN No.11883) Since GCN #11684 observes only one signal (corresponding to spikes at 18866s in our Figure), we request others to check if there were any observations at the times when other VLF signals were seen.