GRB170325A

This page lists all entries on GRB170325A in GRBweb

Summary Fermi GBM IPN Swift GCN 20938 GCN 20940 GCN 20958 GCN 20978

Summary table
Variable Value Source
GRB_name_Fermi GRB170325331
T0 7:56:57.950 UTC Swift
ra 127.4830° Swift
decl 20.5260° Swift
pos_error 1.55e-02° Swift
T90 0.576 s Fermi_GBM
T90_error 0.326 s Fermi_GBM
T90_start 7:56:57.977 UTC Fermi_GBM
fluence 2.57e-07 erg/cm² Fermi_GBM
fluence_error 1.24e-08 erg/cm² Fermi_GBM
T100 0.603 s
GBM_located False
mjd 57837.33122627315 Swift
Fermi GBM table
GRB_name_Fermi GRB170325331
trigger_name bn170325331
ra 127.4829°
decl 20.5261°
pos_error 6.86e+00°
datum 2017-03-25
t_trigger 7:56:58.041 UTC
T90 0.576 s
T90_error 0.326 s
T90_start 7:56:57.977 UTC
fluence 2.57e-07 erg/cm²
fluence_error 1.24e-08 erg/cm²
flux_1024 2.14e+00 erg/cm²/s
flux_1024_error 2.13e-01 erg/cm²/s
flux_1024_time -3.20e-01 erg/cm²/s
flux_64 8.07e+00 erg/cm²/s
flux_64_error 1.21e+00 erg/cm²/s
IPN table
GRB_name GRB170325A
ra 127.4833°
decl 20.5333°
pos_error 5.00e-02°
Swift table
GRB_name GRB170325A
t_trigger 7:56:57.950 UTC
ra 127.4830°
decl 20.5260°
pos_error 1.55e-02°
T90 0.3 s
fluence 8.80e-08 erg/cm²
GCN 20938 table
GRB_name GRB170325A
GCN_number 20938
Detection_method Swift-BAT Det
ra 127.4830°
decl 20.5260°
Circular_text TITLE: GCN CIRCULAR NUMBER: 20938 SUBJECT: GRB 170325A, Swift-BAT detection of a short GRB DATE: 17/03/26 04:36:10 GMT FROM: David Palmer at LANL GRB 170325A, Swift-BAT detection of a short GRB D. M. Palmer (LANL), S. D. Barthelmy (GSFC), J. R. Cummings (CPI), N. Gehrels (GSFC), H. A. Krimm (NSF/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), T. Sakamoto (AGU), M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team): GRB 170325A was detected by Swift/BAT at 2017-03-25 07:56:57.95 UTC. Because the spacecraft was slewing at that time, there was no onboard triggers, and the burst was found later in the ground analysis in response to Fermi-GBM trigger #512121423. Using the data set from T-16 to T+92 sec from the recent telemetry downlink, The BAT ground-calculated position is RA, Dec = 127.483, 20.526 deg which is RA(J2000) = 08h 29m 55.9s Dec(J2000) = +20d 31' 32.5" with an uncertainty of 2.0 arcmin, (radius, sys+stat, 90% containment). The mask-weighted light curve shows a single FRED-like pulse that starts and peaks at ~T0, and ends at ~T+0.4 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+0.4 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.06 +- 0.26. The fluence in the 15-150 keV band is 8.8 +-1.3 x 10^-8 erg/cm2. The 1-sec peak photon flux measured from T-0.30 sec in the 15-150 keV band is 1.1 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence level.
GCN 20940 table
GRB_name GRB170325A
GCN_number 20940
Detection_method Fermi GBM Det
t_trigger 7:56:58.040 UTC
Circular_text TITLE: GCN CIRCULAR NUMBER: 20940 SUBJECT: GRB 170325A: Fermi GBM observation DATE: 17/03/27 17:35:41 GMT FROM: Elisabetta Bissaldi at U.Innsbruk/IAPP E. Bissaldi (Politecnico & INFN Bari), M. Stanbro, and C. Meegan (UAH) report on behalf of the Fermi GBM Team: "At 07:56:58.04 UT on 25 March 2017, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 170325A (trigger 512121423/170325331), which was also detected by the Swift/BAT (Palmer et al. 2017, GCN 20938). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight at the GBM trigger time is 60 degrees. The GBM light curve consists of a single peak with a duration (T90) of about 0.58 s (50-300 keV). The time-averaged spectrum from T0-0.064 s to T0+0.192 s is adequately fit by a power law function with an exponential high-energy cutoff. The power law index is -0.7 +/- 0.2 and the cutoff energy, parameterized as Epeak, is 600 +/- 200 keV. The event fluence (10-1000 keV) in this time interval is (4.8 +/- 0.6)E-7 erg/cm^2. The 64-ms peak photon flux, measured starting from T0 in the 10-1000 keV band, is 7.6 +/- 1.1 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN 20958 table
GRB_name GRB170325A
GCN_number 20958
Detection_method Swift-BAT Det
Circular_text TITLE: GCN CIRCULAR NUMBER: 20958 SUBJECT: GRB 170325A: 15 GHz upper limits from AMI DATE: 17/03/31 15:12:54 GMT FROM: Kunal Mooley at Oxford U K. P. Mooley (Hintze Fellow, Oxford), T. D. Staley, R. P. Fender (Oxford), G. E. Anderson (Curtin), T. Cantwell (Manchester), D. Titterington, S. H. Carey, J. Hickish, Y. C. Perrott, N. Razavi-Ghods, P. Scott (Cambridge), K. Grainge, A. Scaife (Manchester) We followed up the short GRB 170325A, detected in the Swift/BAT ground-based analysis (Palmer et al., GCN 20938), with the AMI Large Array as part of the 4pisky program. We note that this GRB was also detected by Fermi/LAT (Bissaldi et al., GCN 20940). Our observations at 15 GHz on 2016 Mar 27.01, Mar 27.84 and Mar 29.83 (UT; 1.7d, 2.5d and 4.5d post-burst respectively) do not reveal any transient source in the BAT error circle (Palmer et al., GCN 20938), which allows us to place 3sigma upper limits of 113 uJy, 85 uJy and 117 uJy respectively on the radio afterglow of the GRB. We thank the AMI staff for scheduling these observations. The AMI-GRB database is a log of all GRB follow up observations with the AMI, and is available at http://4pisky.org/ami-grb/.
GCN 20978 table
GRB_name GRB170325A
GCN_number 20978
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 20978 SUBJECT: GRB 170325A: optical observations, possible OT/host detection DATE: 17/04/04 20:20:06 GMT FROM: Alexei Pozanenko at IKI, Moscow E. Mazaeva (IKI), A. Pozanenko (IKI), V. Rumyantsev (CrAO), P. Minaev (IKI), E. Klunko (ISTP), A. Volnova (IKI), M. Eselevich (ISTP) report on behalf of larger GRB follow-up collaboration: Цe followed up the short GRB 170325A (Palmer et al., GCN 20938) with AZT-33IK telescope of Sayan observatory (Mondy) an ZTSh telescope of CrAO observatory. The burst was detected by GBM/Fermi (Bissaldi et al., GCN 20940) and also detected as 5.5 sigma non-triggered IBAS event of 0.1 s duration of SPI-ACS/INTEGRAL (see http://grb.rssi.ru/GRB170325A/GRB170325_SPI-ACS.png). We obtained several images in R-filter on March 26, March 29, and April 1 and cover all 90% error box of the BAT/Fermi (Palmer et al., GCN 20938). We investigated variability of sources in the BAT/Fermi error box between the three epochs. One source exhibits marginal fading between first and second epochs. Preliminary photometry of the source is following Date UT start t-T0 Filter Exp. OT Err. UL (mid, days) (s) 2017-03-26 14:10:51 1.28049 R 3600 21.94 0.15 22.2 2017-03-29 21:00:52 4.56314 R 3240 22.27 0.10 23.6 2017-04-01 15:46:59 7.35072 R 4100 22.45 0.25 22.6 the photometry is based on nearby SDSS-DR9 stars SDSS-DR9_id R(Lupton transformations) J082954.53+203317.9 18.69 J083002.05+203031.2 16.74 J082950.18+203013.8 18.25 J082949.90+203106.9 16.65 Coordinates of the source are (J2000) 08:29:57.677 +20:30:51.75 with uncertainty of 0.7 arcsec in both coordinates. The finding chart can be found in http://grb.rssi.ru/GRB170325A/GRB170325A_Mondy_170326_2.png http://grb.rssi.ru/GRB170325A/GRB170325A_CrAO_170329.png The source is not presented in SDSS-DR9, but clearly visible in r(=22.59), i(=22.10) filters, barely visible in u-filter (23.1), and not detected in g and z of SDSS images. We suggest the source is an afterglow and host candidates of the short GRB 170325A.