GRB100424A

This page lists all entries on GRB100424A in GRBweb

Summary IPN Swift GCN 10667 GCN 10668 GCN 10669 GCN 10670 GCN 10671 GCN 10672 GCN 10674 GCN 10675 GCN 10676 GCN 10677 GCN 10679 GCN 10681 GCN 10682 GCN 10687 GCN 10688 GCN 10690 GCN 10692 GCN 10693 GCN 10701 GCN 14291

Summary table
Variable Value Source
T0 16:32:42 UTC GCN_circulars,Swift Det
ra 209.4478° Swift
decl 1.5385° Swift
pos_error 2.20e-04° Swift
T90 104.0 s Swift
T90_start 16:32:42 UTC Swift
fluence 1.50e-06 erg/cm² Swift
redshift 2.4650 GCN_circulars,Other
T100 104.0 s
GBM_located False
mjd 55310.689375 GCN_circulars,Swift Det
IPN table
GRB_name GRB100424A
ra 209.4542°
decl 1.5167°
pos_error 5.00e-02°
redshift 2.4650
Swift table
GRB_name GRB100424A
t_trigger 16:32:42 UTC
ra 209.4478°
decl 1.5385°
pos_error 2.20e-04°
T90 104.0 s
fluence 1.50e-06 erg/cm²
redshift 2.4650
GCN 10667 table
GRB_name GRB100424A
GCN_number 10667
Detection_method Swift Det
t_trigger 16:32:42 UTC
ra 209.4530°
decl 1.5130°
Circular_text TITLE: GCN CIRCULAR NUMBER: 10667 SUBJECT: GRB 100424A: Swift detection of a burst DATE: 10/04/24 16:45:28 GMT FROM: Scott Barthelmy at NASA/GSFC E. A. Hoversten (PSU), S. D. Barthelmy (GSFC), P. A. Evans (U Leicester), C. Guidorzi (U Ferrara), S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU), W.B Landsman (GSFC), C. B. Markwardt (CRESST/GSFC/UMD), F. E. Marshall (NASA/GSFC), P. T. O'Brien (U Leicester), C. Pagani (U Leicester), D. M. Palmer (LANL), M. H. Siegel (PSU) and M. A. Stark (PSU) report on behalf of the Swift Team: At 16:32:42 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 100424A (trigger=420367). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 209.453, +1.513 which is RA(J2000) = 13h 57m 49s Dec(J2000) = +01d 30' 48" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT lightcurve shows nothing as is usual for an image trigger. The XRT began observing the field at 16:34:42.1 UT, 119.8 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 209.4467, +1.5366 which is equivalent to: RA(J2000) = 13h 57m 47.20s Dec(J2000) = +01d 32' 11.7" with an uncertainty of 5.1 arcseconds (radius, 90% containment). No event data are yet available to determine the column density using X-ray spectroscopy. The initial flux in the 2.5 s image was 2.09e-09 erg cm^-2 s^-1 (0.2-10 keV). UVOT took a finding chart exposure of 150 seconds with the White filter starting 128 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 0.03. Burst Advocate for this burst is E. A. Hoversten (hoversten 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.)
GCN 10668 table
GRB_name GRB100424A
GCN_number 10668
Detection_method Swift-XRT Other
ra 209.4478°
decl 1.5386°
Circular_text TITLE: GCN CIRCULAR NUMBER: 10668 SUBJECT: GRB 100424A: Prompt enhanced Swift-XRT position. DATE: 10/04/24 17:10:26 GMT FROM: Phil Evans at U of Leicester P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team: Using 1.4 ks of promptly downlinked XRT data and 1 promptly available UVOT image we find an enhanced position of the XRT afterglow of GRB 100424A (Hoversten et al., GCN Circ. 10667) of RA, Dec 209.4478, 1.5386 which is equivalent to: RA(J2000) = 13h 57m 47.44s Dec(J2000) = +01d 32' 18.8" with an uncertainty of 2.0 arcseconds (radius, 90% containment). Analysis of the promptly available data is online at http://www.swift.ac.uk/sper/420367. Position enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, MNRAS, 397, 1177). This circular is an official product of the Swift-XRT team.
GCN 10669 table
GRB_name GRB100424A
GCN_number 10669
Detection_method Swift-XRT Det
ra 209.4478°
decl 1.5390°
Circular_text TITLE: GCN CIRCULAR NUMBER: 10669 SUBJECT: GRB 100424A: Enhanced Swift-XRT position DATE: 10/04/24 22:50:55 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 1406 s of XRT Photon Counting mode data and 1 UVOT images for GRB 100424A, 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 = 209.44775, +1.53897 which is equivalent to: RA (J2000): 13h 57m 47.46s Dec (J2000): +01d 32' 20.3" 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, MNRAS, 397, 1177). This circular was automatically generated, and is an official product of the Swift-XRT team.
GCN 10670 table
GRB_name GRB100424A
GCN_number 10670
Detection_method Swift-BAT Det
ra 209.4530°
decl 1.5120°
Circular_text TITLE: GCN CIRCULAR NUMBER: 10670 SUBJECT: GRB 100424A, Swift-BAT refined analysis DATE: 10/04/24 23:50:55 GMT FROM: Jay R. Cummings at NASA/GSFC/Swift H. A. Krimm (GSFC/USRA), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), E. A. Hoversten (PSU), 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-60 to T+243 sec from the recent telemetry downlink, we report further analysis of BAT GRB 100424A (trigger #420367) (Hoversten et al., GCN Circ. 10667). The BAT ground-calculated position is RA, Dec = 209.453, 1.512 deg which is RA(J2000) = 13h 57m 48.6s Dec(J2000) = +01d 30' 44.2" with an uncertainty of 1.5 arcmin, (radius, sys+stat, 90% containment). The partial coding was 88%. The mask-weighted lightcurve shows a single broad peak from about T+20 to T+150 sec. T90 (15-350 keV) is 104 +- 15.5 sec (estimated error including systematics). The time-averaged spectrum from T+22.3 to T+148.5 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.83 +- 0.13. The fluence in the 15-150 keV band is 1.5 +- 0.1 x 10^-06 erg/cm2. The 1-sec peak photon flux measured from T+58.28 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/420367/BA/
GCN 10671 table
GRB_name GRB100424A
GCN_number 10671
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 10671 SUBJECT: GRB 100424A: NOT optical observations DATE: 10/04/25 01:19:23 GMT FROM: Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst D. Malesani (DARK/NBI), D. Xu (Weizmann Inst.), A. J. Levan (Univ. Warwick), P. Jakobsson (Univ. Iceland), T. Pursimo (NOT), report on behalf of a larger collaboration: We observed the field of GRB 100424A (Hoversten et al., GCN 10667) with the NOT equipped with ALFOSC in the R, I, and z filters. Observations started on April 24 at 22:38, 23:05, and 23:31 UT in R, I, z, respectively (6.30, 6.74, and 7.21 hr after the GRB), and were affected by the closeby bright Moon (42 deg away, 85% full) and some clouds. We do not detect any new object within the refined XRT error circle (Evans, GCN 10668; Evans et al., GCN 10669). The limiting magnitudes are R(Vega) = 22.5 and z(AB) = 21.9, calibrated against the USNO-B1 and SDSS catalogs, respectively. Given the relatively large X-ray flux, we encourage NIR observations.
GCN 10672 table
GRB_name GRB100424A
GCN_number 10672
Detection_method Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 10672 SUBJECT: GRB 100424A: WHT z-band observations DATE: 10/04/25 02:12:06 GMT FROM: Andrew Levan at U.of Leicester A.J. Levan, C. Copperwheat, E. Breedt (U. Warwick), D. Malesani (DARK/NBI) report on behalf of a larger collaboration: "We observed the localization of GRB 100424A (Hoversten et al. GCN 10667) using the WHT and ACAM. Observations begin at April 25 00:18, approximately 9 hours after the burst. We obtained 4x200s exposures in the z-band. No source is visible within the enhanced XRT location (Evans et al. GCN 10669) to a limiting magnitude of z>23.2, calibrated against SDSS. The deep z-band limit, coupled with apparently bright early X-ray afterglow is suggestive of either a highly extinguished, or high redshift burst."
GCN 10674 table
GRB_name GRB100424A
GCN_number 10674
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 10674 SUBJECT: GRB 100424A: Swift-XRT refined analysis DATE: 10/04/25 04:13:36 GMT FROM: Michael Stroh at PSU/Swift M. C. Stroh, D. Grupe and E. A. Hoversten (PSU) report on behalf of the Swift-XRT team: We have analysed 641 s of XRT data for GRB 100424A (Hoversten et al. GCN Circ. 10667), from 126 s to 769 s after the BAT trigger. The data comprise 509 s in Windowed Timing (WT) mode with the remainder in Photon Counting (PC) mode. The light curve can be modelled with a series of power-law decays. The initial decay index is alpha=0.63 (+/-0.14). At T+288 s the decay steepens to an alpha of 1.41 (+0.27, -0.19) before breaking again at T+526 s to a final decay with index alpha=2.8 (+0.9, -0.6). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.26 (+/-0.06). The best-fitting absorption column is 1.62 (+0.22, -0.21) x 10^21 cm^-2, in excess of the Galactic value of 2.3 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 5.8 x 10^-11 (6.5 x 10^-11) erg cm^-2 count^-1. If the light curve continues to decay with a power-law decay index of 2.8, the count rate at T+24 hours will be 5.1 x 10^-6 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 3.0 x 10^-16 (3.3 x 10^-16) erg cm^-2 s^-1. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00420367. This circular is an official product of the Swift-XRT team.
GCN 10675 table
GRB_name GRB100424A
GCN_number 10675
Detection_method correction
Circular_text TITLE: GCN CIRCULAR NUMBER: 10675 SUBJECT: GRB 100424A: PAIRITEL NIR Upper Limits DATE: 10/04/25 06:14:03 GMT FROM: Adam Morgan at U.C. Berkeley A. N. Morgan and J. S. Bloom (UC Berkeley) report: We observed the field of GRB 100424A (Hoversten et al., GCN 10667) with the 1.3m PAIRITEL located at Mt. Hopkins, Arizona. Observations began at 2010-04-25 03:51:19 UT, ~11.3 hours after the Swift Trigger, under high airmass. In mosaics (effective exposure time of 0.74 hours) taken simultaneously in the J, H, and Ks filters, we do not detect any source within the enhanced XRT error circle (Evans et al., GCN 10669). The preliminary photometry yields: post burst t_mid (hr) exp.(hr) filt U. Limit (3 sig) 11.81 0.74 J > 19.3 11.81 0.74 H > 18.4 11.81 0.74 Ks > 17.0 Further observations are ongoing to obtain a deeper limit. All magnitudes are given in the Vega system, calibrated to 2MASS. No correction for Galactic extinction has been made to the above reported values.
GCN 10676 table
GRB_name GRB100424A
GCN_number 10676
Detection_method GROND
Circular_text TITLE: GCN CIRCULAR NUMBER: 10676 SUBJECT: GRB 100424A: GROND Upper Limits DATE: 10/04/25 06:32:41 GMT FROM: Thomas Kruehler at MPE/MPI F. Olivares, T. Kruehler and J. Greiner (all MPE Garching) report on behalf of the GROND team: We observed the field of GRB 100424A (Swift trigger 420367; Hoversten et al., GCN 10667) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2 m MPI/ESO telescope at La Silla Observatory (Chile). Observations started at 00:16 UT on April 25, 7.7 hours after the GRB trigger, and continued for 3 hours. The observations were severely affected by passing cirrus clouds. In our first stacked images of 24 min total integration time in g'r'i'z' and 20 min in JHK, we do not (see also Malesani et al., GCN 10671, Levan et al., GCN 10672, Morgan & Bloom GCN 10675) detect a source within the enhanced Swift/XRT error circle (Evans et al., GCN 10669) down to the following preliminary 3 sigma limiting magnitudes (all in the AB system): g' > 23.03 r' > 23.37 i' > 22.96 z' > 23.04 J > 21.77 H > 21.21 K > 20.29 Later images do not increase these limiting magnitudes due to worse sky conditions. These limits were derived by calibrating the images against SDSS/2MASS field stars and are not corrected for the Galactic foreground extinction corresponding to a reddening of E_(B-V)= 0.03 in the direction of the burst (Schlegel et al. 1998).
GCN 10677 table
GRB_name GRB100424A
GCN_number 10677
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 10677 SUBJECT: GRB 100424A : Lulin early z'-band upper limit DATE: 10/04/25 07:46:11 GMT FROM: Yuji Urata at Nat. Central U. K.Y. Huang (ASIAA), Y. Urata, P. Tsai (NCU) on behalf of EAFON report; We observed the field of GRB 100424A (Hoversten et al., GCN 10667) in r' and z'-band with the LOT. Observations started at 17:52 UT on April 24, ~80 min after the Swift Trigger. In our z'-band stacked image shows no new object within the enhanced Swift/XRT position (Evans et al., GCN 10669) down to the following preliminary limiting magnitudes, ---------------------------- Time(hr) Filter Limit(AB) ---------------------------- 2.16 z' 20.6 ----------------------------
GCN 10679 table
GRB_name GRB100424A
GCN_number 10679
Detection_method MITSuME
Circular_text TITLE: GCN CIRCULAR NUMBER: 10679 SUBJECT: GRB100424A: MITSuME optical upper limits DATE: 10/04/25 08:14:00 GMT FROM: Daisuke Kuroda at OAO/NAOJ D. Kuroda, K. Yanagisawa, Y. Shimizu, H. Toda (OAO, NAOJ), S. Nagayama (NAOJ), M. Yoshida (Hiroshima), K. Ohta (Kyoto) and N. Kawai(Tokyo Tech) report on behalf of the MITSuME collaboration: We observed the field of GRB 100424A (Hoversten et al. GCNC 10667) with the optical three color (g', Rc and Ic) CCD camera attached to the MITSuME 50cm telescope of Okayama Astrophysical Observatory. The observation started on 2010-04-24 16:34:56 UT (~2.2 min after the burst). We did not find any new point source within the XRT error circle (Evans, GCNC 10668; Evans et al., GCNC 10669) in all the three bands. Three sigma upper limits of the OT are listed below. We used SDSS catalog for flux calibration. T0+[day] MID-UT T-EXP[sec] g' Rc Ic ------------------------------------------------------ 0.00527 16:40:18 540.0 >18.4 >18.5 >17.7 0.04356 17:35:26 5940.0 >19.6 >20.0 >19.4 ------------------------------------------------------ T0+ : Elapsed time after the burst [day] T-EXP: Total Exposure time [sec]
GCN 10681 table
GRB_name GRB100424A
GCN_number 10681
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 10681 SUBJECT: GRB 100424A: D50 optical limits DATE: 10/04/25 09:35:32 GMT FROM: Jan Strobl at AI AS CR,Ondrejov Jan Strobl (1), Martin Jelinek (2), Cyril Polasek (1), Petr Kubanek (2,3), Martin Nekola (1), Matus Kocka (1), Michal Jakubec (1) and Rene Hudec (1) (1. ASU AVCR Ondrejov, 2. IAA Granada, 3. GACE Valencia) We observed the field of Swift GRB 100424A (Hoversten et al., GCNC 10667) with the 0.5m telescope D50 in Ondrejov (Czech Republic), starting at 23:27:02 UT, i.e. 06:54:20 after the trigger. A sequence of 20s unfiltered images was obtained. We coadded 60x20s exposure, obtaining an image with a limitting magnitude Rc~19.3, with an effective exposure time 7.35h after the trigger (23:54UT). We do not detect any new source within the XRT localization (Evans et al., GCN10699). This message can be cited.
GCN 10682 table
GRB_name GRB100424A
GCN_number 10682
Detection_method Other
ra 209.4476°
decl 1.5386°
Circular_text TITLE: GCN CIRCULAR NUMBER: 10682 SUBJECT: GRB 100424A: Gemini/NIRI Candidate Afterglow DATE: 10/04/25 09:47:55 GMT FROM: S. Bradley Cenko at Caltech S. B. Cenko, J. S. Bloom, A. N. Morgan, and B. E. Cobb (UC Berkeley) report on behalf of a larger collaboration: We have imaged the field of GRB 100424A (Hoversten et al., GCN 10667) with the Near-InfraRed Imager and Spectrometer mounted on the 8 m Gemini North telescope. Observations were taken in the J and K filters beginning at 6:28 UT on 25 April 2010 (~ 14 hours after the burst). At the edge of the refined XRT error circle (Evans et al., GCN 10669) we identify a faint point source in both filters. Referencing both the astrometry and photometry to the 2MASS source 13574681+0131477, we measure a position (J2000) of RA: 13:57:47.43 Dec: +01:32:18.9 and approximate magnitudes of K = 19.9, J = 22.1 (both Vega magnitudes). The J-K color indicates a red afterglow, though does not necessarily require a high-redshift origin (e.g., Levan et al., GCN 10672). No other objects are detected inside the XRT error circle. Without evidence for variability, we cannot definitively confirm if this source is the afterglow of GRB 100424A. Further observations are planned to search for fading. We wish to thank the staff at Gemini Observatory, in particular Kristin Chiboucas, for promptly executing these observations.
GCN 10687 table
GRB_name GRB100424A
GCN_number 10687
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 10687 SUBJECT: GRB 100424A: Liverpool Telescope Upper Limits DATE: 10/04/25 14:25:15 GMT FROM: Zach Cano at ARI/John Moores Liverpool Z. Cano, A. Melandri (Liverpool JMU), C. Guidorzi (U. Ferrara), C. Mundell, R.J. Smith, D. Bersier, I.A. Steele, S. Kobayashi, C.J. Mottram, (Liverpool JMU), A. Gomboc (U. Ljubljana) report, on behalf of a larger collaboration: We observed the field of GRB 100424A (Hoversten et al. GCNC 10667) with the Liverpool Telescope starting 20:54 UT on April 24, 2010. We do not detect the NIR afterglow discovered by Cenko et al. (GCN 10682), nor any other object within the enhanced XRT error circle (Evans, GCN 10668; Evans et al., GCN 10669) down to the following limits: ------------------------------------------------------------------- Mid Exposure Total T-To (hrs) Exposure Time (min) Filter upper limit ------------------------------------------------------------------- 6.91 30 B >21.5 6.92 50 I >21.8 8.38 20 R >21.7 ------------------------------------------------------------------- The upper limits are for an isolated object in our images and are calibrated using nearby stars in the USNO-B1 catalogue. No correction for Galactic extinction has been made.
GCN 10688 table
GRB_name GRB100424A
GCN_number 10688
Detection_method Swift-UVOT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 10688 SUBJECT: GRB 100424A: Swift/UVOT Upper Limits DATE: 10/04/25 14:39:39 GMT FROM: Peter Curran at MSSL P.A. Curran (MSSL-UCL) and E. Hoversten (PSU) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 100424A 128 s after the BAT trigger (Hoversten et al., GCN Circ. 10667). No optical afterglow consistent with the refined XRT position (Evans et al., GCN Circ. 10669) or the proposed NIR counterpart (Cenko et al. (GCN Circ. 10682) is detected in the initial UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Poole et al. 2008, MNRAS, 383, 627) for the initial finding charts (FC) and exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag ---------------------------------------------- white 128 278 147 >20.8 (FC) u 288 537 246 >20.0 (FC) white 128 2046 444 >21.2 v 618 1930 156 >19.2 b 543 2028 156 >20.1 u 288 2003 382 >20.1 w1 668 1979 156 >19.7 m2 642 1955 97 >19.1 w2 594 5584 193 >20.0 The values quoted above are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.08 in the direction of the burst (Schlegel et al. 1998).
GCN 10690 table
GRB_name GRB100424A
GCN_number 10690
Detection_method Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 10690 SUBJECT: GRB 100424A: Gemini/NIRI H-band observations DATE: 10/04/26 07:27:45 GMT FROM: S. Bradley Cenko at Caltech S. B. Cenko, A. N. Morgan, and J. S. Bloom (UC Berkeley) report on behalf of a larger collaboration: We have obtained further imaging of the field of GRB 100424A (Hoversten et al., GCN 10667) with the Near InfraRed Imager and Spectrometer mounted on the 8 m Gemini North telescope. Following our report of a detection of a candidate afterglow in the J and K filters (Cenko et al., GCN 10682), we obtained a sequence of H-band images beginning at 9:29 UT on 25 April 2010 (~ 17 hours after the burst). The candidate afterglow is also detected in the H-band. Using the PAIRITEL imaging of the field for photometric calibration (Morgan and Bloom, GCN 10675), we measure a magnitude of H = 20.9 (Vega) at this time. Combined with our previous J and K photometry (and assuming the afterglow decays in time like a power-law with index alpha=-1), the candidate infrared afterglow appears consistent with a relatively steep spectral power-law index of beta ~ 2.5-3.0 across all three bands. This suggests the afterglow is reddened due predominantly to dust in the host galaxy of the GRB, and not an extremely high-redshift (z > 7) origin, as would be suggested by the presence of host galaxy extinction from the X-ray afterglow spectrum (Stroh et al., GCN 10674). We wish to thank the staff at Gemini Observatory for assistance in executing these observations.
GCN 10692 table
GRB_name GRB100424A
GCN_number 10692
Detection_method Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 10692 SUBJECT: GRB 100424A: NIR Afterglow Confirmation DATE: 10/04/27 00:05:44 GMT FROM: S. Bradley Cenko at Caltech S. B. Cenko, J. S. Bloom, D. A. Perley, A. N. Morgan, B. E. Cobb (UC Berkeley) and A. J. Levan (U. Warwick) report on behalf of a larger collaboration: We have obtained a second epoch of K-band imaging of the field of GRB 100424A (Hoversten et al., GCN 10667) with the Near InfraRed Imager and Spectrometer mounted on the 8 m Gemini North telescope. Observations began at 11:23 UT on 26 April 2010 (~ 43 hours after the burst). The previously identified candidate in the XRT error circle (Cenko et al., GCN 10682) has faded by 0.9 +/- 0.1 mag, confirming the object is indeed the NIR afterglow of GRB 100424A. Assuming negligible contribution from an underlying host galaxy, the inferred power-law decay index, alpha ~ 0.7, is relatively shallow. We wish to thank the staff at Gemini Observatory, in particular Kristin Chiboucas, for executing these observations.
GCN 10693 table
GRB_name GRB100424A
GCN_number 10693
Detection_method Optical
ra 209.4398°
decl 1.5582°
Circular_text TITLE: GCN CIRCULAR NUMBER: 10693 SUBJECT: GRB 100424A: CrAO optical observations DATE: 10/04/27 07:54:33 GMT FROM: Alina Volnova at SAI MSU V. Rumyantsev, D. Shakhovskoy (CrAO), A. Volnova (SAI MSU), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: We observed the field of the Swift GRB 100424A (Hoversten et al., GCN 10667) with AZT-11 telescope of CrAO observatory between (UT) Apr. 24 18:01 - 19:18 under seeing of about 3 arcsec. We detected a probable source at coordinates (J2000) RA = 13:57:47.64 Dec = +01:32:21.06 with an uncertainty of 0.5 arcsec in both coordinates. The probable source is located 2.8 arcsec from the enhanced XRT position with an uncertainty (radius) of 1.7 arcsec (Evans et al., GCN 10669). Due to low S/N we cannot confirm the detected source is a real object. We do not detect any source at the position of afterglow candidate (Cenko, et al., GCN 10682, Cenko, et al., GCN 10690). The photometry of the probable source and upper limit of the point-like source in a stacked image based on USNO-B1.0 star (RA(J2000) = 13:57:45.54 Dec(J2000)= +01:33:29.7) and assuming R=17.80 is following: T0+ Filter, Exposure, mag. UL (mid, d) (s) 0.0882 R 21x180 20.1 +/- 0.3 20.4 The combined image can be found at http://grb.rssi.ru/GRB100424A/GRB100424a_R_AZT11.gif
GCN 10701 table
GRB_name GRB100424A
GCN_number 10701
Detection_method Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 10701 SUBJECT: GRB 100424a. Radio observations DATE: 10/04/28 23:30:36 GMT FROM: Dale A. Frail at NRAO Dale A. Frail (NRAO) and Poonam Chandra (RMC) report on behalf of a larger collaboration: "We observed the localization of GRB 100424A (Hoversten et al. GCN 10667) the Expanded Very Large Array (EVLA) on April 27.14 UT at a center frequency of 8.46 GHz. We do not detect any radio source anywhere within the refined XRT error circle (Evans et al., GCN 10669) to a 3-sigma limit of 66 uJy. The EVLA is still undergoing active commissioning and we caution that these results should be considered preliminary. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc."
GCN 14291 table
GRB_name GRB100424A
GCN_number 14291
Detection_method Other
redshift 2.4650
Circular_text TITLE: GCN CIRCULAR NUMBER: 14291 SUBJECT: GRB 100424A: Keck host detection and VLT/X-shooter redshift DATE: 13/03/12 16:07:54 GMT FROM: Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst D. Malesani, D. Xu, J. P. U. Fynbo, T. Kruehler (DARK/NBI), D. A. Perley (Caltech), S. D. Vergani (CNRS/GEPI), P. Goldoni (APC/IRFU-CEA), report on behalf of the GRB GTO X-shooter collaboration: We observed the field of GRB 100424A (Hoversten et al., GCN 10667) using the Keck-I telescope equipped with the LRIS instrument. Observations were carried out on 2010 July 8.2 UT (74.5 days after the burst), simultaneously in the g and I bands, for a total exposure time of 35 and 32 min, respectively. Consistent with the position of the NIR afterglow (Cenko et al., GCNs 10682, 10690, 10692), we detected a source with g = 26 (AB) and I = 24.4 (Vega). We consider this object to be the host galaxy of GRB 100424A. A spectrum of this source was taken on 2013 March 11.3 UT with the ESO VLT equipped with the X-shooter spectrograph, covering the wavelength range 3000-25000 AA. The exposure time was 8x600 s. In the NIR arm, we detect four emission lines, that we interpret as [O III](4959), [O III](5007), Hbeta, and [O II](3727), all at a common redshift of z = 2.465. In the UVB arm, we also detect weak Lyalpha in emission at the same redshift. We acknowledge excellent support from the observing staff at Mauna Kea and Paranal, in particular Thomas Rivinius and Claudio Melo.