GRB190427A

This page lists all entries on GRB190427A in GRBweb

Summary Fermi GBM IPN Swift GCN 24261 GCN 24264 GCN 24265 GCN 24272 GCN 24282 GCN 24287 GCN 24288 GCN 24290 GCN 24293 GCN 24330 GCN 24333 GCN 24339

Summary table
Variable Value Source
GRB_name_Fermi GRB190427190
T0 4:34:15 UTC GCN_circulars,Swift Det
ra 280.2170° Swift
decl 40.3040° Swift
pos_error 1.86e-02° Swift
T90 0.368 s Fermi_GBM
T90_error 0.072 s Fermi_GBM
T90_start 4:34:15.065 UTC Fermi_GBM
fluence 5.34e-07 erg/cm² Fermi_GBM
fluence_error 1.22e-08 erg/cm² Fermi_GBM
T100 0.433 s
GBM_located False
mjd 58600.19045138889 GCN_circulars,Swift Det
Fermi GBM table
GRB_name_Fermi GRB190427190
trigger_name bn190427190
ra 280.2129°
decl 40.3219°
pos_error 5.29e+00°
datum 2019-04-27
t_trigger 4:34:15.081 UTC
T90 0.368 s
T90_error 0.072 s
T90_start 4:34:15.065 UTC
fluence 5.34e-07 erg/cm²
fluence_error 1.22e-08 erg/cm²
flux_1024 3.72e+00 erg/cm²/s
flux_1024_error 2.68e-01 erg/cm²/s
flux_1024_time -4.48e-01 erg/cm²/s
flux_64 1.88e+01 erg/cm²/s
flux_64_error 1.96e+00 erg/cm²/s
IPN table
GRB_name GRB190427A
ra 280.2125°
decl 40.3167°
pos_error 5.00e-02°
Swift table
GRB_name GRB190427A
t_trigger 4:34:15 UTC
ra 280.2170°
decl 40.3040°
pos_error 1.86e-02°
T90 0.3 s
fluence 1.30e-07 erg/cm²
GCN 24261 table
GRB_name GRB190427A
GCN_number 24261
Detection_method Swift Det
t_trigger 4:34:15 UTC
ra 280.2130°
decl 40.3220°
Circular_text TITLE: GCN CIRCULAR NUMBER: 24261 SUBJECT: GRB 190427A: Swift detection of a short burst DATE: 19/04/27 04:43:39 GMT FROM: David Palmer at LANL A. Tohuvavohu (PSU), N. J. Klingler (PSU), A. Y. Lien (GSFC/UMBC), D. M. Palmer (LANL) and M. H. Siegel (PSU) report on behalf of the Neil Gehrels Swift Observatory Team: At 04:34:15 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 190427A (trigger=900730). Swift's slew will be delayed due to an observing constraint. The BAT on-board calculated location is RA, Dec 280.213, +40.322 which is RA(J2000) = 18h 40m 51s Dec(J2000) = +40d 19' 20" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single short structure with a duration of about 0.5 sec. The peak count rate was ~6000 counts/sec (15-350 keV), at ~0 sec after the trigger. Due to an observing constraint, Swift will not slew until T0+43.4 minutes. There will be no XRT or UVOT data until this time. Burst Advocate for this burst is A. Tohuvavohu (aaronb AT swift.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/)
GCN 24264 table
GRB_name GRB190427A
GCN_number 24264
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 24264 SUBJECT: GRB 190427A: Swift-XRT observations DATE: 19/04/27 06:14:37 GMT FROM: Phil Evans at U of Leicester S. Campana (INAF-OAB), P.A. Evans (U. Leicester), J.P. Osborne (U. Leicester), D.N. Burrows (PSU), J.A. Kennea (PSU) and G. Tagliaferri (INAF-OAB) report on behalf of the Swift-XRT team: The XRT began observing the field of GRB 190427A at 05:36:30.6 UT, 3735.8 seconds after the BAT trigger. No source was detected in 142 s of promptly downlinked data. We are waiting for the full dataset to detect and localise the XRT counterpart.
GCN 24265 table
GRB_name GRB190427A
GCN_number 24265
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 24265 SUBJECT: GRB 190427A: NOT optical observations DATE: 19/04/27 06:25:28 GMT FROM: Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst L. Izzo (HETH/IAA-CSIC), D. B. Malesani (DAWN/NBI and DARK/NBI), D. Xu (NAOC/CAS), and N. Jannsen (NOT), report: We observed the field of the Swift GRB 190427A (Tohuvavohu et al., GCN 24261; Campana et al., GCN 24264) using the Nordic Optical Telescope (NOT) located in La Palma (Canary Islands, Spain), equipped with the ALFOSC camera. We have obtained a series of 2 exposures of 300 s each in the SDSS r’, i’ and z’ filters. The first r'-band image was acquired starting on 2019 Apr 27.19742 UT (602 s after the GRB). Visual comparison with the Pan-STARRS archival images reveals no new sources inside the BAT error circle, down to a limiting magnitude r = 23.5 AB (calibrated against Pan-STARRS sources). Further analysis is ongoing.
GCN 24272 table
GRB_name GRB190427A
GCN_number 24272
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 24272 SUBJECT: GRB 190427A: BOOTES-1 and BOOTES-5/JGT early follow-up observations DATE: 19/04/27 08:22:34 GMT FROM: Alberto J. Castro-Tirado at IAA-CSIC Y.-D. Hu, X.-Y.Li, E. Fernandez-Garcia, A. Ayala, and A. J. Castro-Tirado (IAA-CSIC), D. Hiriart and W. H. Lee (UNAM), S. Jeong and I. H. Park (SKKU), I. Carrasco, A. Castellon, C. Perez del Pulgar (Univ. de Malaga), S. B. Pandey (ARIES) and M. D. Caballero-Garcia (ASU-CAS, CZ) on behalf of a larger collaboration, report: Following the detection of the short-duration GRB 190427A (Tohuvavohu et al. GCNC 24261), both the 30cm BOOTES-1 robotic telescope in Mazagon (Huelva, southern Spain) and the BOOTES-5/JGT robotic telescope at Observatorio Astronomico Nacional in San Pedro Martir (Mexico), automatically responded at 04:35:01 UT (~46 s after trigger) and 04:55:00 UT (~0.33 hr after trigger) respectively. No optical afterglow is detected down to 17 mag and 20 mag respectively. This is consistent with the no-detection reported by Lipunov et al. (GCNC 24263) and Izzo et al. (GCNC 24265). Further analysis is ongoing.
GCN 24282 table
GRB_name GRB190427A
GCN_number 24282
Detection_method Swift-BAT Det
Circular_text TITLE: GCN CIRCULAR NUMBER: 24282 SUBJECT: GRB 190427A: RATIR Optical and NIR Observations DATE: 19/04/27 14:08:29 GMT FROM: Eleonora Troja at NASA/GSFC/UMD Eleonora Troja (GSFC), Nat Butler (ASU), Alan M. Watson (UNAM), Alexander Kutyrev (GSFC), William H. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UVI), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), Jesús González (UNAM), Carlos Roman-Zuniga (UNAM), Harvey Moseley (GSFC), John Capone (UMD), V. Zach Golkhou (U. Wash.), and Vicki Toy (UMD) report: We observed the field of GRB 190427A (Tohuvavohu, et al., GCN 24261) with the Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the 1.5m Harold Johnson Telescope at the Observatorio Astronomico Nacional on Sierra San Pedro Martir from 2019/04 27.28 to 2019/04 27.30 UTC (2.22 to 2.53 hours after the BAT trigger), obtaining a total of 0.20 hours exposure in the r and i bands and 0.06 hours exposure in the Z, Y, J, and H bands. In comparison with the SDSS DR9 catalog, we detect no new source brighter than r~22 AB mag within the BAT error circle. We thank the staff of the Observatorio Astronómico Nacional in San Pedro Martir.
GCN 24287 table
GRB_name GRB190427A
GCN_number 24287
Detection_method Swift-BAT Det
Circular_text TITLE: GCN CIRCULAR NUMBER: 24287 SUBJECT: GRB 190427A: COATLI Optical Observations DATE: 19/04/27 15:13:14 GMT FROM: Alan M Watson at UNAM Alan M. Watson (UNAM), Eleonora Troja (GSFC), Nat Butler (ASU), Rosa L. Becerra (UNAM), Diego González (UNAM), William H. Lee (UNAM), Margarita Pereyra (UNAM), Carlos Román-Zúñiga (UNAM) and Alexander Kutyrev (GSFC) report: We observed the field of GRB 190427A (Tohuvavohu et al., GCN Circ. 24261) with the COATLI 50-cm telescope and interim imager at the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir (http://coatli.astroscu.unam.mx) from 2019-02-04 05:28:30 to 06:36:27 (from 0.9 to 2.0 hours after the trigger), obtaining a total of 3000 seconds of exposure in the w filter. Comparing to the USNO and Pan-STARRS1 catalogs, we do not detect any new sources brighter than w = 21 in the BAT error region. Our w magnitudes are calibrated against the Pan-STARRS1 catalog, are on an approximate AB system, and are not corrected for Galactic extinction in the direction of the GRB. We thank the COATLI technical team and the staff of the Observatorio Astronómico Nacional.
GCN 24288 table
GRB_name GRB190427A
GCN_number 24288
Detection_method MITSuME
Circular_text TITLE: GCN CIRCULAR NUMBER: 24288 SUBJECT: GRB 190427A: MITSuME Akeno optical upper limits DATE: 19/04/27 15:58:22 GMT FROM: Katsuhiro L. Murata at Nagoya U K. L. Murata, M. Oeda, K.Shiraishi, K. Iida, M. Niwano, R. Adachi, Y. Yatsu, and N. Kawai (TokyoTech) report on behalf of the MITSuME collaboration: We searched for the optical counterpart of GRB 190427A (Tohuvavohu et al., GCN Circular #24261) with the optical three color (g', Rc, and Ic) CCD cameras attached to the MITSuME 50 cm telescope of Akeno Observatory, Yamanashi, Japan. The observation started on 13:16:48 UT. We did not find any new point sources within the BAT circle (Tohuvavohu et al., GCN Circular #24261) in all three bands. We obtained the following 5-sigma limits for the magnitudes. T0+[hour] MID-UT T-EXP[sec] 5-sigma limits ------------------------------------------------------------------------------------------------ ~8.7 13:35:08 1620(g'),1560(Rc),1980(Ic) g'>17.8,Rc>18.2,Ic >18.6 ------------------------------------------------------------------------------------------------ T0+ : Elapsed time after the burst T-EXP: Total Exposure time We used GSC2.3 catalog for flux calibration. The magnitudes are expressed in the AB system.
GCN 24290 table
GRB_name GRB190427A
GCN_number 24290
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 24290 SUBJECT: GRB 190427A: Lick/Nickel telescope optical observations DATE: 19/04/27 16:07:18 GMT FROM: Weikang Zheng at UC Berkeley Keto Zhang, Shaunak Modak, WeiKang Zheng and Alexei V. Filippenko (UC Berkeley) report on behalf of the KAIT GRB team: We observed the field of GRB 190427A (Tohuvavohu et al., GCN 24261) with the 1-m Nickel telescope located at Lick observatory, California. Observations started about 4.31 hours after the burst. A total of 5 image in R band were taken with each exposure time of 600s. No viable counterparts were identified in our images. The limiting magnitude of our 5 combined image is R~22.0 mag calibrated to the Pan-STARRS1 catalog.
GCN 24293 table
GRB_name GRB190427A
GCN_number 24293
Detection_method Fermi GBM Det
t_trigger 4:34:15.080 UTC
Circular_text TITLE: GCN CIRCULAR NUMBER: 24293 SUBJECT: GRB 190427A: Fermi GBM detection DATE: 19/04/27 17:14:36 GMT FROM: Christian Malacaria at NASA-MSFC/USRA C. Malacaria (NASA-MSFC/USRA), A. von Kienlin (MPE) and C. Meegan (UAH) report on behalf of the Fermi GBM Team: "At 04:34:15.08 UT on 27 04 2019, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 190427A (trigger 578032460 / 190427190). The event was also detected by the Swift/BAT (Tohuvavohu et al. 2019, GCN 24261) The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight at the GBM trigger time is 106 degrees. The GBM light curve consists of a dominant pulse with following structure and a duration (T90) of about 0.37 s (50-300 keV). The time-averaged spectrum from T0-0.064 s to T0+0.384 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -1.05 +/- 0.18 and the cutoff energy, parameterized as Epeak, is 246.40 +/- 78.20 keV. The event fluence (10-1000 keV) in this time interval is (4.855 +/- 0.717)E-07 erg/cm^2. The 64-msec peak photon flux measured starting from T0+0.0 s in the 10-1000 keV band is 18.8 +/- 1.1 ph/s/cm^2." The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog: https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html For Fermi GBM data and info, please visit the official Fermi GBM Support Page: https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/
GCN 24330 table
GRB_name GRB190427A
GCN_number 24330
Detection_method Swift-BAT Det
ra 280.2170°
decl 40.3040°
Circular_text TITLE: GCN CIRCULAR NUMBER: 24330 SUBJECT: GRB 190427A, Swift-BAT refined analysis DATE: 19/04/28 15:40:56 GMT FROM: Amy Lien at GSFC T. N. Ukwatta (LANL), S. D. Barthelmy (GSFC), J. R. Cummings (CPI), H. A. Krimm (NSF/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), A. Tohuvavohu (PSU) (i.e. the Swift-BAT team): Using the data set from T-61 to T+242 sec from the recent telemetry downlink, we report further analysis of BAT GRB 190427A (trigger #900730) (Tohuvavohu et al., GCN Circ. 24261). The BAT ground-calculated position is RA, Dec = 280.217, 40.304 deg which is RA(J2000) = 18h 40m 52.0s Dec(J2000) = +40d 18' 15.6" with an uncertainty of 2.4 arcmin, (radius, sys+stat, 90% containment). The partial coding was 68%. The mask-weighted light curve shows a double-peaked structure that starts from ~ T0 and ends at ~T+0.3. The main peak occurs at ~T0, followed by a weaker peak at ~T+0.2 s. T90 (15-350 keV) is 0.3 +- 0.1 sec (estimated error including systematics). The time-averaged spectrum from T-0.0 to T+0.3 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.17 +- 0.21. The fluence in the 15-150 keV band is 1.3 +- 0.2 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T-0.33 sec in the 15-150 keV band is 1.6 +- 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/900730/BA/
GCN 24333 table
GRB_name GRB190427A
GCN_number 24333
Detection_method Swift-UVOT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 24333 SUBJECT: GRB 190427A: Swift/UVOT Upper Limits DATE: 19/04/28 20:09:21 GMT FROM: Paul Kuin at MSSL N. P. M. Kuin (UCL-MSSL) and A. Tohuvavohu (PSU) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 190427A 3737 s after the BAT trigger (Tohuvavohu et al., GCN Circ. 24261). No optical afterglow consistent with the BAT position (Ukwatta et al., GCN Circ. 24330) is detected in the initial UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the initial exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag u 3737 3936 197 >19.9 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.06 in the direction of the burst (Schlegel et al. 1998).
GCN 24339 table
GRB_name GRB190427A
GCN_number 24339
Detection_method CALET
Circular_text TITLE: GCN CIRCULAR NUMBER: 24339 SUBJECT: GRB 190427A: CALET Gamma-Ray Burst Monitor detection DATE: 19/04/29 07:47:46 GMT FROM: Valentin Pal'shin at AGU N. Cannady (LSU), A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU), Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN), Y. Asaoka, S. Ozawa, S. Torii (Waseda U), T. Tamura, Y. Shimizu (Kanagawa U), M. L. Cherry (LSU), S. Ricciarini (U of Florence), P. S. Marrocchesi (U of Siena) and the CALET collaboration: The short GRB 190427A (Swift-BAT trigger #900730: Tohuvavohu et al., GCN Circ. 24261, Ukwatta et al., GCN Circ. 24330; Fermi GBM detection: Malacaria, von Kienlin and Meegan, GCN Circ. 24293) was detected in ground analysis of the CALET Gamma-ray Burst Monitor (CGBM) data near the Swift-BAT trigger time at T0=04:34:14.95 UT on 27 April 2019. The burst signal was seen only by the SGM detector. The source location (Ukwatta et al., GCN Circ. 24330) was out of the HXM detectors' FOVs and likely blocked by the ISS structures. The burst light curve shows a single bin (125 ms) spike with a signal-to-noise ratio of 9.0 in the 40-1000 keV range. The ground processed light curve is available at http://cgbm.calet.jp/cgbm_trigger/ground/1240374828/ The CALET data used in this analysis are provided by the Waseda CALET Operation Center located at the Waseda University.