GRB150530A

This page lists all entries on GRB150530A in GRBweb

Summary Fermi GBM IPN Swift GCN 17888 GCN 17889 GCN 17890 GCN 17891 GCN 17892 GCN 17893 GCN 17894 GCN 17900

Summary table
Variable Value Source
GRB_name_Fermi GRB150530488
T0 11:42:14.583 UTC Fermi_GBM
ra 327.5122° Swift
decl 57.5166° Swift
pos_error 2.07e-04° Swift
T90 7.168 s Fermi_GBM
T90_error 0.572 s Fermi_GBM
T90_start 11:42:14.583 UTC Fermi_GBM
fluence 3.49e-06 erg/cm² Fermi_GBM
fluence_error 4.09e-08 erg/cm² Fermi_GBM
T100 10.037 s
GBM_located False
mjd 57172.48766878472 Fermi_GBM
Fermi GBM table
GRB_name_Fermi GRB150530488
trigger_name bn150530488
ra 327.5108°
decl 57.5164°
pos_error 3.19e+00°
datum 2015-05-30
t_trigger 11:42:15.607 UTC
T90 7.168 s
T90_error 0.572 s
T90_start 11:42:14.583 UTC
fluence 3.49e-06 erg/cm²
fluence_error 4.09e-08 erg/cm²
flux_1024 6.72e+00 erg/cm²/s
flux_1024_error 3.09e-01 erg/cm²/s
flux_1024_time 2.82e+00 erg/cm²/s
flux_64 8.35e+00 erg/cm²/s
flux_64_error 1.41e+00 erg/cm²/s
IPN table
GRB_name GRB150530A
ra 327.5250°
decl 57.5667°
pos_error 5.00e-02°
Swift table
GRB_name GRB150530A
t_trigger 11:42:18 UTC
ra 327.5122°
decl 57.5166°
pos_error 2.07e-04°
T90 6.62 s
fluence 1.80e-06 erg/cm²
GCN 17888 table
GRB_name GRB150530A
GCN_number 17888
Detection_method Swift Det
t_trigger 11:42:18 UTC
ra 327.5230°
decl 57.4900°
Circular_text TITLE: GCN CIRCULAR NUMBER: 17888 SUBJECT: GRB 150530A: Swift detection of a burst DATE: 15/05/30 11:59:01 GMT FROM: Rhaana Starling at U of Leicester R. L. C. Starling (U Leicester), N. Gehrels (NASA/GSFC), J. A. Kennea (PSU), F. E. Marshall (NASA/GSFC) and K. L. Page (U Leicester) report on behalf of the Swift Team: At 11:42:18 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 150530A (trigger=642018). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 327.523, +57.490 which is RA(J2000) = 21h 50m 06s Dec(J2000) = +57d 29' 25" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single peak with some structure with a duration of about 10 sec. The peak count rate was ~2500 counts/sec (15-350 keV). The XRT began observing the field at 11:44:00.8 UT, 102.7 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source with an enhanced position: RA, Dec 327.5109, 57.5164 which is equivalent to: RA(J2000) = 21h 50m 02.61s Dec(J2000) = +57d 30' 58.9" with an uncertainty of 3.3 arcseconds (radius, 90% containment). This location is 96 arcseconds from the BAT onboard position, within the BAT error circle. This position may be improved as more data are received; the latest position is available at http://www.swift.ac.uk/sper. We cannot determine whether the source is fading at the present time. A power-law fit to a spectrum formed from promptly downlinked event data gives a column density consistent with the Galactic value of 1.00 x 10^22 cm^-2 (Willingale et al. 2013). UVOT took a finding chart exposure of 150 seconds with the White filter starting 106 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 large, but uncertain extinction expected. Burst Advocate for this burst is R. L. C. Starling (rlcs1 AT star.le.ac.uk). 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 17889 table
GRB_name GRB150530A
GCN_number 17889
Detection_method Swift-XRT Det
ra 327.5130°
decl 57.5168°
Circular_text TITLE: GCN CIRCULAR NUMBER: 17889 SUBJECT: GRB 150530A: Enhanced Swift-XRT position DATE: 15/05/30 15:55:52 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 418 s of XRT Photon Counting mode data and 1 UVOT images for GRB 150530A, 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 = 327.51297, +57.51681 which is equivalent to: RA (J2000): 21h 50m 3.11s Dec (J2000): +57d 31' 00.5" with an uncertainty of 2.2 arcsec (radius, 90% confidence). This position may be improved as more data are received. The latest position can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, MNRAS, 397, 1177). This circular was automatically generated, and is an official product of the Swift-XRT team.
GCN 17890 table
GRB_name GRB150530A
GCN_number 17890
Detection_method Swift-BAT Det
ra 327.5110°
decl 57.5190°
Circular_text TITLE: GCN CIRCULAR NUMBER: 17890 SUBJECT: GRB 150530A: Swift-BAT refined analysis DATE: 15/05/30 16:15:22 GMT FROM: Scott Barthelmy at NASA/GSFC C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), R. L. C. Starling (U Leicester), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team): Using the data set from T-61 to T+242 sec from recent telemetry downlinks, we report further analysis of BAT GRB 150530A (trigger #642018) (Strling, et al., GCN Circ. 17888). The BAT ground-calculated position is RA, Dec = 327.511, 57.519 deg, which is RA(J2000) = 21h 50m 02.6s Dec(J2000) = +57d 31' 07.4" with an uncertainty of 1.2 arcmin, (radius, sys+stat, 90% containment). The partial coding was 17%. The mask-weighted light curve shows a couple overlapping peaks starting at ~T-10 sec, peaking at ~T+2 sec, and ending at ~T+40 sec. T90 (15-350 keV) is 6.62 +- 0.84 sec (estimated error including systematics). The time-averaged spectrum from T-4.21 to T+3.49 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.49 +- 0.11. The fluence in the 15-150 keV band is 1.8 +- 0.1 x 10^-06 erg/cm2. The 1-sec peak photon flux measured from T+0.48 sec in the 15-150 keV band is 4.1 +- 0.6 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/642018/BA/
GCN 17891 table
GRB_name GRB150530A
GCN_number 17891
Detection_method Fermi GBM Det
t_trigger 11:42:15.610 UTC
Circular_text TITLE: GCN CIRCULAR NUMBER: 17891 SUBJECT: GRB 150530A: Fermi GBM observation DATE: 15/05/30 18:45:28 GMT FROM: George A. Younes at USRA/NASA/MSFC Yu H.-F. (MPE), Younes G. (USRA at GWU), and Meegan C. (UAH) report on behalf of the Fermi GBM Team: "At 11:42:15.61 UT, on 2015 May 30, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 150530A (trigger 454678938 / 150530488) which was also detected by Swift (Starling et al. 2015, GCN 17888). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight is about 46 degrees. The GBM light curve consists of two peaks with a duration (T90) of 7 s (50-300 keV). The time-averaged spectrum from T0-4.6 s to T0+6.7 s is well fit by a BAND function with Epeak = 126 +/- 14 keV, alpha = -0.8 +/- 0.1, and beta = -2.4 +/- 0.2. The event fluence (10-1000 keV) in this time interval is (4.1 +/- 0.2)E-06 erg/cm^2. The 1.024-sec peak photon flux measured starting from T0+2.8 s in the 10-1000 keV band is 6.7 +/- 0.3 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN 17892 table
GRB_name GRB150530A
GCN_number 17892
Detection_method Swift-UVOT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 17892 SUBJECT: GRB 150530A: Swift/UVOT Upper Limits DATE: 15/05/30 21:29:27 GMT FROM: Alice Breeveld at MSSL-UCL M. De Pasquale (UCL-MSSL) and R. L. C. Starling (U Leicester)report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 150530A 106 s after the BAT trigger (Starling et al., GCN Circ. 17888). No optical afterglow consistent with the XRT position (Goad et al. GCN Circ. 17889) 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 first finding chart (FC) exposure and subsequent exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white_FC 106 256 147 >20.1 u_FC 319 562 238 >19.2 white 106 5690 541 >21.0 v 4465 6101 393 >19.3 b 3849 5485 393 >20.4 u 319 5280 435 >19.7 w1 4875 5075 197 >19.5 m2 4670 6306 393 >19.9 w2 4260 5896 393 >20.1 The magnitudes in the table are not corrected for the strong Galactic extinction due to the reddening of E(B-V) = 1.81 in the direction of the burst (Schlegel et al. 1998).
GCN 17893 table
GRB_name GRB150530A
GCN_number 17893
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 17893 SUBJECT: GRB 150530A: Swift-XRT refined Analysis DATE: 15/05/30 23:59:04 GMT FROM: Phil Evans at U of Leicester A. Melandri (INAF-OAB), P. D'Avanzo (INAF-OAB), J.A. Kennea (PSU), B. Sbarufatti (INAF-OAB/PSU), D.N. Burrows (PSU), K.L. Page (U. Leicester), C. Pagani (U. Leicester), A.P. Beardmore (U. Leicester), V. D'Elia (ASDC) and R.L.C. Starling report on behalf of the Swift-XRT team: We have analysed 9.2 ks of XRT data for GRB 150530A (Starling et al. GCN Circ. 17888), from 90 s to 22.6 ks after the BAT trigger. The data comprise 6 s in Windowed Timing (WT) mode (taken while Swift was slewing), with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Goad et al. (GCN Circ. 17889). The light curve can be modelled with a power-law decay with a decay index of alpha=0.98 (+/-0.06). A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 1.9 (+/-0.5). The best-fitting absorption column is 2.2 (+0.9, -0.8) x 10^22 cm^-2, in excess of the Galactic value of 1.0 x 10^22 cm^-2 (Willingale et al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 6.6 x 10^-11 (1.3 x 10^-10) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 2.2 (+0.9, -0.8) x 10^22 cm^-2 Galactic foreground: 1.0 x 10^22 cm^-2 Excess significance: 2.7 sigma Photon index: 1.9 (+/-0.5) If the light curve continues to decay with a power-law decay index of 0.98, the count rate at T+24 hours will be 1.6 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.1 x 10^-13 (2.2 x 10^-13) erg cm^-2 s^-1. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00642018. This circular is an official product of the Swift-XRT team.
GCN 17894 table
GRB_name GRB150530A
GCN_number 17894
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 17894 SUBJECT: GRB 150530A: RATIR Optical Observations DATE: 15/05/31 19:31:54 GMT FROM: Alan M. Watson at Instituto de Astronomia UNAM Alan M. Watson (UNAM), Nat Butler (ASU), Alexander Kutyrev (GSFC), William H. Lee (UNAM), Michael G. Richer (UNAM), Chris Klein (UCB), Ori Fox (UCB), J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (ORAU/GSFC), Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), José A. de Diego (UNAM), Leonid Georgiev (UNAM), Jesús González (UNAM), Carlos Román-Zúñiga (UNAM), Neil Gehrels (GSFC), and Harvey Moseley (GSFC) report: We observed the field of GRB 150530A (Starling et al., GCN 17888) with the Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the 1.5m Harold Johnson Telescope at the Observatorio Astronómico Nacional on Sierra San Pedro Mártir from 2015/05 31.32 to 2015/05 31.45 UTC (20.08 to 23.21 hours after the BAT trigger), obtaining a total of 2.49 hours exposure in the r, i, and z bands. For a source within the Swift-XRT error circle, in comparison with 2MASS, we obtain the following upper limits (3-sigma): r > 24.42 i > 24.18 z > 20.44 These magnitudes are in the AB system and are not corrected for Galactic extinction in the direction of the GRB. We thank the staff of the Observatorio Astronómico Nacional in San Pedro Mártir.
GCN 17900 table
GRB_name GRB150530A
GCN_number 17900
Detection_method Konus-Wind Det
t_trigger 11:42:16.529 UTC
Circular_text TITLE: GCN CIRCULAR NUMBER: 17900 SUBJECT: Konus-Wind observation of GRB 150530A DATE: 15/06/03 17:40:38 GMT FROM: Anastasia Tsvetkova at Ioffe Institute S. Golenetskii, R.Aptekar, D. Frederiks, V. Pal'shin, P. Oleynik, M. Ulanov, D. Svinkin, A. Tsvetkova, A. Lysenko, and T. Cline on behalf of the Konus-Wind team, report: The long-duration GRB 150530A (Swift-BAT trigger #642018: Starling et al., GCN 17888; Markwardt et al., GCN 17890; Fermi GBM detection: Yu, Younes and Meegan, GCN 17891) triggered Konus-Wind at T0=42136.529 s UT (11:42:16.529). The burst light curve shows a single pulse lasting from ~T0-4 s to ~T0+6 s. The emission is seen up to ~1.2 MeV. As observed by Konus-Wind, the burst had a fluence of 2.54(-0.26,+0.28)x10^-6 erg/cm2, and a 64-ms peak energy flux, measured from T0+0.082 s, of 1.06(-0.43,+0.43)x10^-6 erg/cm2/s (both in the 20 keV - 10 MeV energy range). The time-integrated spectrum of the burst (measured from T0 to T0+8.448 s) is best fit in the 20 keV - 1.2 MeV range by a power law with exponential cutoff model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) with alpha = -0.63(-0.38,+0.46), and Ep = 114(-17,+23) keV (chi2 = 59/58 dof). Fitting by a GRB (Band) model yields the same alpha and Ep, and an upper limit on the high energy photon index: beta < -3.07 (chi2 = 59/57 dof). The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB150530_T42136/ All the quoted errors are at the 90% confidence level. All the quoted values are preliminary.