GRB230328B

This page lists all entries on GRB230328B in GRBweb

Summary Fermi GBM IPN Swift GCN 33526 GCN 33527 GCN 33528 GCN 33529 GCN 33530 GCN 33531 GCN 33532 GCN 33533 GCN 33534 GCN 33535 GCN 33536 GCN 33537 GCN 33538 GCN 33539 GCN 33540 GCN 33541 GCN 33543 GCN 33544 GCN 33547 GCN 33549 GCN 33550 GCN 33556 GCN 33559 GCN 33609 GCN 34141

Summary table
Variable Value Source
GRB_name_Fermi GRB230328621
T0 14:54:46.790 UTC Fermi_GBM
ra 291.0078° Swift
decl 80.0096° Swift
pos_error 5.70e-05° Swift
T90 18.88 s Fermi_GBM
T90_error 1.619 s Fermi_GBM
T90_start 14:54:46.790 UTC Fermi_GBM
fluence 9.13e-06 erg/cm² Fermi_GBM
fluence_error 2.03e-08 erg/cm² Fermi_GBM
redshift 0.0900 Swift
T100 20.44 s
GBM_located False
mjd 60031.62137488426 Fermi_GBM
Fermi GBM table
GRB_name_Fermi GRB230328621
trigger_name bn230328621
ra 301.8200°
decl 75.5900°
pos_error 2.92e+00°
datum 2023-03-28
t_trigger 14:54:47.430 UTC
T90 18.88 s
T90_error 1.619 s
T90_start 14:54:46.790 UTC
fluence 9.13e-06 erg/cm²
fluence_error 2.03e-08 erg/cm²
flux_1024 1.27e+01 erg/cm²/s
flux_1024_error 2.89e-01 erg/cm²/s
flux_1024_time 1.41e+00 erg/cm²/s
flux_64 1.74e+01 erg/cm²/s
flux_64_error 1.29e+00 erg/cm²/s
IPN table
GRB_name GRB230328B
ra 290.9875°
decl 80.0167°
pos_error 5.00e-02°
Swift table
GRB_name GRB230328B
t_trigger 14:54:48 UTC
ra 291.0078°
decl 80.0096°
pos_error 5.70e-05°
T90 19.23 s
fluence 4.30e-06 erg/cm²
redshift 0.0900
GCN 33526 table
GRB_name GRB230328B
GCN_number 33526
Detection_method Fermi GBM final loc
t_trigger 14:54:47 UTC
ra 301.8000°
decl 75.6000°
Circular_text TITLE: GCN CIRCULAR NUMBER: 33526 SUBJECT: GRB 230328B: Fermi GBM Final Real-time Localization DATE: 23/03/28 15:05:06 GMT FROM: Fermi GBM Team at MSFC/Fermi-GBM The Fermi GBM team reports the detection of a likely LONG GRB At 14:54:47 UT on 28 Mar 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230328B (trigger 701708092.430074 / 230328621). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 301.8, Dec = 75.6 (J2000 degrees, equivalent to J2000 20h 07m, 75d 35'), with a statistical uncertainty of 3.2 degrees. The angle from the Fermi LAT boresight is 38.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230328621/quicklook/glg_skymap_all_bn230328621.png The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230328621/quicklook/glg_healpix_all_bn230328621.fit The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230328621/quicklook/glg_lc_medres34_bn230328621.gif
GCN 33527 table
GRB_name GRB230328B
GCN_number 33527
Detection_method Swift Det
t_trigger 14:54:48 UTC
ra 290.9860°
decl 80.0160°
Circular_text TITLE: GCN CIRCULAR NUMBER: 33527 SUBJECT: GRB 230328B: Swift detection of a burst with an optical afterglow DATE: 23/03/28 15:06:35 GMT FROM: David Palmer at LANL J.D. Gropp (PSU), S. Dichiara (PSU), R. A. J. Eyles-Ferris (U Leicester), N. P. M. Kuin (UCL-MSSL), F. E. Marshall (NASA/GSFC), M. J. Moss (GWU), K. L. Page (U Leicester), D. M. Palmer (LANL) and M. H. Siegel (PSU) report on behalf of the Neil Gehrels Swift Observatory Team: At 14:54:48 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 230328B (trigger=1162001). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 290.986, +80.016 which is RA(J2000) = 19h 23m 57s Dec(J2000) = +80d 00' 58" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a complex GRB structure with a duration of about 20 sec, followed by a bright flaring afterglow visible below 25 keV for at least 200 s. The peak count rate was ~4375 counts/sec (15-350 keV), at ~0 sec after the trigger. The XRT began observing the field at 14:56:38.8 UT, 110.3 seconds after the BAT trigger. Using promptly downlinked data we find a fading, uncatalogued X-ray source located at RA, Dec 291.00418, 80.00951 which is equivalent to: RA(J2000) = 19h 24m 01.00s Dec(J2000) = +80d 00' 34.2" with an uncertainty of 3.6 arcseconds (radius, 90% containment). This location is 25 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 https://www.swift.ac.uk/sper. A power-law fit to a spectrum formed from promptly downlinked event data gives a column density in excess of the Galactic value (6.28 x 10^20 cm^-2, Willingale et al. 2013), with an excess column of 3.6 (+1.76/-1.56) x 10^21 cm^-2 (90% confidence). UVOT took a finding chart exposure of 150 seconds with the White filter starting 114 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at RA(J2000) = 19:24:01.84 = 291.00765 DEC(J2000) = +80:00:34.5 = 80.00959 with a 90%-confidence error radius of about 0.62 arc sec. This position is 0.7 arc sec. from the center of the XRT error circle. The estimated magnitude is 18.22 with a 1-sigma error of about 0.15. No correction has been made for the expected extinction corresponding to E(B-V) of 0.070. Burst Advocate for this burst is J.D. Gropp (jdg44 AT 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 33528 table
GRB_name GRB230328B
GCN_number 33528
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 33528 SUBJECT: GRB 230328B: Mondy optical afterglow confirmation DATE: 23/03/28 16:31:55 GMT FROM: Alexei Pozanenko at IKI, Moscow N. Pankov (HSE), E. Klunko (ISTP), A. Pozanenko (IKI), S. Belkin (IKI) report on behalf of GRB IKI FuN: We observed the field of Swift GRB 230328B (Gropp et al. GCN 33527) with AZT-33IK telescope of Mondy observatory in R-filter on 2023-03-28 starting (UT) 15:27:18. We clearly detect the optical afterglow of GRB 230328B (Gropp et al. GCN 33527) at the position of (J2000) 19 24 01.828 +80 00 34.53 with an error of 0.5 arcsec in both coordinates, which coincides with the position of UVOT (Gropp et al. GCN 33527). Preliminary photometry of a stack of the first 5 images is following Date UT start t-T0 Exp. Filter OT Err. UL(3sigma) (mid, days) (s) 2023-03-28 15:27:18 0.026047 5*60 R 18.9 0.2 21.1 The photometry is based on nearby USNO-B1.0 stars.
GCN 33529 table
GRB_name GRB230328B
GCN_number 33529
Detection_method Swift-XRT Det
ra 291.0071°
decl 80.0095°
Circular_text TITLE: GCN CIRCULAR NUMBER: 33529 SUBJECT: GRB 230328B: Enhanced Swift-XRT position DATE: 23/03/28 19:00:09 GMT FROM: Phil Evans at U of Leicester J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) report on behalf of the Swift-XRT team. Using 1128 s of XRT Photon Counting mode data and 3 UVOT images for GRB 230328B, 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 = 291.00713, +80.00952 which is equivalent to: RA (J2000): 19h 24m 1.71s Dec (J2000): +80d 00' 34.3" with an uncertainty of 2.1 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 33530 table
GRB_name GRB230328B
GCN_number 33530
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 33530 SUBJECT: GRB 230328B: Mondy, AbAO and Kitab optical observations DATE: 23/03/28 21:40:25 GMT FROM: Alexei Pozanenko at IKI, Moscow S. Belkin (IKI), R. Ya. Inasaridze (AbAO), E. Klunko (ISTP), A. Novichonok (Petrozavodsk State University, KIAM), A. Pozanenko (IKI), N. Pankov (HSE, IKI), D. Datashvili (AbAO), V. R. Ayvazian (AbAO), G. V. Kapanadze (AbAO) report on behalf of GRB IKI FuN: We observed the field of Swift GRB 230328B (Gropp et al. GCN 33527; Osborne et al. GCN 33529) till now with AZT-33IK telescope of Mondy observatory in R-filter, RC-36 telescope of Kitab observatory in Clear, AS-32 telescope of Abastumani observatory in R-filter. The optical afterglow (Gropp et al. GCN 33527; Pankov et al. GCN 33528) is detected in Mondy and Abastumani, and not detected in Kitab observatory. Preliminary photometry of a stacked images is following Date UT start t-T0 Filter Exp. OT Err. UL(3sigma) (mid, days) (s) 2023-03-28 16:19:20 0.062188 R 5*120 19.34 0.10 21.0 2023-03-28 16:37:07 0.042338 Clear 19*60 n/d n/d 17.6 2023-03-28 16:15:48 0.086725 R 104*60 19.50 0.10 21.2 The photometry is based on nearby USNO-B1.0 stars. Approximation of above photometry in R-filter and photometry reported early (GCN 33528) results in the power law index of -0.45 of slow decay LC of GRB 230328B.
GCN 33531 table
GRB_name GRB230328B
GCN_number 33531
Detection_method Fermi GBM Det
t_trigger 14:54:47.430 UTC
Circular_text TITLE: GCN CIRCULAR NUMBER: 33531 SUBJECT: GRB 230328B: Fermi GBM observation DATE: 23/03/28 22:50:25 GMT FROM: Sarah Dalessi at UAH S. Dalessi (UAH) and C. Meegan (UAH) report on behalf of the Fermi GBM Team: "At 14:54:47.43 UT on 28 March 2023, the Fermi Gamma-Ray Burst Monitor (GBM) triggered and located GRB 230328B (trigger 701708092 / 230328621), which was also detected by the Swift/BAT (J.D. Gropp et al. 2023, GCN 33527) The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight at the GBM trigger time is 38 degrees. The GBM light curve consists of a single burst with a duration (T90) of about 19 s (50-300 keV). The time-averaged spectrum from T0-3.5 s to T0+19.1 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -1.16 +/- 0.03 and the cutoff energy, parameterized as Epeak, is 169.6 +/- 9.9 keV. The event fluence (10-1000 keV) in this time interval is (9.4 +/- 0.3)E-06 erg/cm^2. The 1 sec peak photon flux measured starting from T0+1.4 s in the 10-1000 keV band is 12.7 +/- 0.3 ph/s/cm^2. A Band function fits the spectrum equally well with Epeak = 125.0 +/- 11.3 keV, alpha = -1.03 +/- 0.06, and beta = -2.10+/- 0.09. 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 33532 table
GRB_name GRB230328B
GCN_number 33532
Detection_method AstroSat CZTI
Circular_text TITLE: GCN CIRCULAR NUMBER: 33532 SUBJECT: GRB 230328B: AstroSat CZTI detection DATE: 23/03/29 01:58:51 GMT FROM: Varun Bhalerao at Indian Inst of Tech G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration: Analysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of GRB 230328B which was also detected by Fermi-GBM (GCN Circ. 33526), Swift-BAT (Gropp et. al, GCN Circ. 33527). The source was clearly detected in the 20-200 keV energy range. The light curve peaks at 2023-03-28 14:54:49.5 UTC. The measured peak count rate associated with the burst is 244.7 (+41.3 -43.3) counts/s above the background in the combined data of all quadrants, with a total of 1090 (+249 -250) counts. The local mean background count rate was 409.1 (+2.4 -3.1) counts/s. Using cumulative rates, we measure a T90 of 11.78 (+4.17 -4.51) s. It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2023-03-28 14:54:48.3 UTC. The measured peak count rate is 561.0 (+68.3 -74.6) counts/s above the background in the combined Veto data of all quadrants, with a total of 2819 (+428 -485) counts. The local mean background count rate was 1299.3 (+5.2 -5.5) counts/s. We measure a T90 of 12.86 (+5.41 -4.68) s from the cumulative Veto light curve. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project. CZTI GRB detections are reported regularly on the payload site at: http://astrosat.iucaa.in/czti/?q=grb
GCN 33533 table
GRB_name GRB230328B
GCN_number 33533
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 33533 SUBJECT: GRB 230328B: Swift-XRT refined Analysis DATE: 23/03/29 03:11:19 GMT FROM: Phil Evans at U of Leicester A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), A. Melandri (INAF-OAR), T. Sbarrato (INAF-OAB), P. D'Avanzo (INAF-OAB), J.A. Kennea (PSU), A. Tohuvavohu (U. Toronto), D.N. Burrows (PSU), J.P. Osborne (U. Leicester) and J.D. Gropp report on behalf of the Swift-XRT team: We have analysed 9.2 ks of XRT data for GRB 230328B (Gropp et al. GCN Circ. 33527), from 94 s to 28.9 ks after the BAT trigger. The data comprise 9 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 Osborne et al. (GCN Circ. 33529). The late-time light curve (from T0+4.3 ks) can be modelled with a power-law decay with a decay index of alpha=1.06 (+/-0.07). A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 1.89 (+/-0.08). The best-fitting absorption column is 1.37 (+0.26, -0.24) x 10^21 cm^-2, in excess of the Galactic value of 6.3 x 10^20 cm^-2 (Willingale et al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.6 x 10^-11 (4.5 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 1.37 (+0.26, -0.24) x 10^21 cm^-2 Galactic foreground: 6.3 x 10^20 cm^-2 Excess significance: 5.1 sigma Photon index: 1.89 (+/-0.08) If the light curve continues to decay with a power-law decay index of 1.06, the count rate at T+24 hours will be 0.052 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.9 x 10^-12 (2.3 x 10^-12) erg cm^-2 s^-1. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/01162001. This circular is an official product of the Swift-XRT team.
GCN 33534 table
GRB_name GRB230328B
GCN_number 33534
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 33534 SUBJECT: GRB 230328B: Nanshan/NEXT optical upper limit DATE: 23/03/29 03:45:19 GMT FROM: Dong Xu at NAOC/CAS T.H. Lu, S.Q. Jiang, S.Y. Fu, X. Liu (NAOC), Z.P. Zhu (NAOC, HUST), D. Xu (NAOC), X. Gao (Urumqi No.1 Senior High School), J.Z. Liu (XAO) report: We observed the field of GRB 230328B detected by Swift (Gropp et al., GCN 33527),using the NEXT-0.6m optical telescope located at Nanshan, Xinjiang, China. Observations started at 16:39:57 UT on 2023-03-28, i.e., 1.75 hr after the Swift/BAT trigger. The previously reported optical afterglow (e.g., Pankov et al., GCN 33528; Belkin et al., GCN 33530) is marginally detected in our stacked image. Preliminary photometry of the afterglow has r ~ 19.1 mag, calibrated by nearby PanSTARRS stars.
GCN 33535 table
GRB_name GRB230328B
GCN_number 33535
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 33535 SUBJECT: GRB 230328B: OASDG optical observations DATE: 23/03/29 08:38:29 GMT FROM: Luca Izzo at DARK/NBI A. Catapano (OASDG), and L. Izzo (DARK/NBI) report: We observed the field of GRB 230328B (Gropp et al., GCN #33527) with the 0.5m telescope of the Osservatorio Astronomico S. Di Giacomo located in Agerola, Italy ( https://osservatorio.astrocampania.it/ ). We obtained two sets of 8x240s images each in the Rc and in the Ic filter under good weather conditions, with the two sets of observations separated by three hours each. In the first dataset, we detect a faint source in the stacked Ic images at the enhanced position reported by Swift-XRT (Osborne et al., GCN #33529) and by optical telescopes (Pankov et al., GCN #33528; Belkin et al., GCN #33530, Lu et al., GCN #33534). We measure a preliminary magnitude of ~19.5 mag (AB), at exposure mid-time of MJD 60031.8 (5.1 hours after the GRB detection). We also report an upper limit of ~20.0 mag in the Rc band. In the second set of observations, the source is not detected in both filters, with upper limits of Rc > 20.2, and Ic > 19.8, respectively (MJD 60031.9, 8.1 hours after the GRB). The calibration was performed using nearby stars in the Pan-STARRS PS1 catalog, and using transformation equations to Rc and Ic magnitudes. Further analyses are ongoing.
GCN 33536 table
GRB_name GRB230328B
GCN_number 33536
Detection_method Optical
ra 291.0075°
decl 80.0096°
Circular_text TITLE: GCN CIRCULAR NUMBER: 33536 SUBJECT: GRB 230328B: GIT optical follow-up DATE: 23/03/29 14:22:27 GMT FROM: Varun Bhalerao at Indian Inst of Tech A. Suresh (IITB), V. Swain (IITB), H. Kumar (IITB), P. Dorjay (IAO), V. Bhalerao (IITB), G. C. Anupama(IIA), S. Barway (IIA) report on behalf of the GIT team: We observed GRB 230328B detected by Swift-BAT and optical afterglow discovered by Swift-UVOT (GCN 33527), with the 0.7m GROWTH-India Telescope (GIT). The observations started at 16:51:27.896 UT on 2023-03-28, 116.66 mins after the Swift-BAT trigger. We obtained multiple 300s exposures in the g', r', i', and z' filters. In stacked images for two bands, we clearly detected the afterglow at R.A.= 19h 24m 01.8s, DEC.= 80d 00' 34.5", consistent with the enhanced Swift-XRT position (GCN 33533). The photometric results follow as: ------------------------------------------------------------------- JD (mid) | T_mid-T0(hrs) | Filter| Total Exposure (s) | Magnitude (AB) | ------------------------------------------------------------------- 2460032.22721302 | 2.539 | r' | 1200 |20.181 +/- 0.054 | 2460032.23485986 | 2.723 | i' | 1200 |19.672 +/- 0.078 | 2460032.23490645 | 2.724 | g' | 600 |>20.089 | 2460032.24251012 | 2.906 | z' | 1200 |>18.503 | ------------------------------------------------------------------- These magnitudes are consistent with the reported optical afterglow detections (N. Pankov et al., GCN #33528; S. Belkin et al., GCN #33530; T.H. Lu et al., GCN #33534; A. Catapano et al., GCN #33535). The magnitudes are calibrated against PanSTARRS DR1 (Chambers et al., 2016) and not corrected for Galactic extinction. The GROWTH India Telescope (GIT; Kumar et al. 2022) is a 70-cm telescope with a 0.7-degree field of view, set up by the Indian Institute of Astrophysics (IIA) and the Indian Institute of Technology Bombay (IITB) with funding from DST-SERB and IUSSTF. It is located at the Indian Astronomical Observatory (Hanle), operated by IIA. We acknowledge funding by the IITB alumni batch of 1994, which partially supports operations of the telescope. Telescope technical details are available at https://sites.google.com/view/growthindia/.
GCN 33537 table
GRB_name GRB230328B
GCN_number 33537
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 33537 SUBJECT: GRB 230328B: OHP/T120 optical observations DATE: 23/03/29 14:52:49 GMT FROM: Benjamin Schneider at MIT C. Adami (LAM), B. Schneider (MIT), M. Birlan, T. Hromakina (Obs. de Paris), S. Basa (LAM), E. Le Floc'h, D. Turpin, D. Götz (CEA Paris-Saclay), S. D. Vergani (GEPI, Obs. de Paris), report on behalf of a larger collaboration: We observed the field of GRB 230328B (Gropp et al., GCN 33527; Osborne et al., GCN 33529; Dalessi et al., GCN 33531; Waratkar et al. GCN 33532) using the T120cm telescope at Observatoire de Haute-Provence (France). Six exposures were obtained in the Rc band (2x300s + 4x600s) from 28 March 2023 18:51:01 UT to 28 March 2023 20:13:46 UT (mid time ~4.5h after trigger). In the combined frame, we clearly detect the source and obtain the following magnitude: Rc = 20.03 +/- 0.10 mag (AB) The photometric calibration was performed using nearby stars from the PanSTARRS catalog converted in Rc and the magnitude is not corrected for Galactic extinction. The value is consistent with early observations obtained by Pankov et al. (GCN 33528), Belkin et al. (GCN 33530) and Lu et al. (GCN 33534), and the upper limit reported by Catapano & Izzo (GCN 33535) at a similar epoch. We acknowledge the excellent support from Observatoire de Haute Provence.
GCN 33538 table
GRB_name GRB230328B
GCN_number 33538
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 33538 SUBJECT: GRB 230328B: Liverpool Telescope afterglow detection DATE: 23/03/29 16:01:52 GMT FROM: Ben Gompertz at U of Birmingham B. P. Gompertz (U. Birmingham), D. B. Malesani (U. Radboud and DAWN/NBI) and A. J. Levan (U. Radboud) report: We observed GRB 230328B (Fermi GBM Team, GCN 33526; Gropp et al., GCN 33527) with the IO:O optical camera on the 2m robotic Liverpool Telescope. Observations began on March 29, 2023 at 03:20:58 UT (~12.4 hr after the Fermi and Swift triggers) and consist of a series of 15x120 s exposures in each of the SDSS r' and i' filters. We detect the optical afterglow first reported by Swift-UVOT (Gropp et al. GCN 33527) with the following magnitudes: r' = 21.16 0.06 i' = 20.75 0.07 Magnitudes are in the AB system, calibrated against nearby PS1 stars (Chambers et al., 2016), and are not corrected for the Galactic reddening of E(B-V) = 0.06 magnitudes along the line of sight (Schlafly & Finkbeiner 2011).
GCN 33539 table
GRB_name GRB230328B
GCN_number 33539
Detection_method correction
Circular_text TITLE: GCN CIRCULAR NUMBER: 33539 SUBJECT: GRB 230328B NUTTelA-TAO / BSTI Early Measurements DATE: 23/03/29 18:00:30 GMT FROM: Toktarkhan Komesh at Nazarbayev University T. Komesh (NU), Zh. Maksut (NU), B. Grossan (UCB, NU), Zh. Abdullayev (NU), M. Krugov (FAI), report on behalf of the Energetic Cosmos Laboratory: The Nazarbayev University Transient Telescope at Assy-Turgen Astrophysical Observatory (NUTTelA-TAO) pointed at GRB230328B on receipt of an automated GCN / BAT position alert, observing in Sloan g', r' and i' bands, with the Burst Simultaneous Three-Channel Imager (BSTI; Grossan, Kumar & Smoot 2019, JHEA, 32, 14). We started observations at UT 2023-03-28 14:55:23, 41 s after the BAT trigger. Observations were made under clear conditions. A new and changing source consistent with the XRT position (Osborne 2023, GCN 33529) was detected. Note that these observations provide essentially full-time coverage, simultaneous in all three bands. We report the following photometric values for the OT: tc-t0(s) g'(mag) exposure_time (s) -------- ------- -------- 68 17.1 54 125 17.1 60 185 17.5 60 245 17.6 60 305 18.0 60 365 18.0 60 440 18.6 90 530 18.8 90 620 19.1 90 725 19.1 120 845 19.8 120 965 17.7 120 tc-t0(s) r'(mag) i'(mag) exposure_time (s) ------ -------- ------ ------- 45 16.5 16.1 7.5 53 16.5 15.9 7.5 60 16.4 16.0 7.5 68 16.8 16.0 7.5 75 16.4 15.9 7.5 83 16.6 16.1 7.5 90 16.5 15.9 7.5 119 16.8 16.1 15 134 16.7 16.2 15 149 16.6 16.2 15 164 17.0 16.3 15 179 16.8 16.3 15 194 17.0 16.3 15 209 16.8 16.6 15 224 17.0 16.8 15 239 17.2 16.7 15 254 17.2 16.8 15 269 17.3 16.7 15 284 17.2 16.8 15 299 17.2 16.9 15 314 17.2 17.1 15 329 17.4 17.1 15 344 17.5 16.9 15 359 17.6 17.3 15 374 17.4 16.9 15 389 17.6 17.6 15 404 17.8 17.1 15 419 17.8 16.9 15 434 17.5 17.1 15 449 17.6 17.3 15 464 17.8 17.4 15 479 17.4 17.0 15 494 18.1 17.1 15 509 17.5 17.3 15 524 17.7 17.1 15 539 18.4 17.5 15 554 17.6 17.2 15 569 17.9 17.7 15 584 18.0 17.2 15 599 17.6 17.6 15 614 17.7 17.4 15 629 17.8 17.5 15 644 17.6 17.2 15 659 17.8 17.5 15 674 17.6 17.6 15 689 18.1 17.3 15 704 18.0 17.5 15 719 17.8 17.5 15 734 17.9 17.5 15 749 18.1 17.3 15 764 18.1 17.3 15 779 18.2 17.8 15 794 18.0 17.6 15 809 18.3 17.5 15 824 18.5 17.5 15 839 18.2 17.4 15 854 18.1 17.4 15 869 18.0 18.4 15 884 17.8 17.8 15 899 18.4 17.8 15 914 18.4 17.1 15 929 17.9 18.1 15 944 17.8 17.3 15 959 18.3 18.3 15 974 18.1 17.1 15 989 18.1 17.9 15 1004 18.3 17.6 15 Uncertainties are estimated at ~ 0.1 mag for all three filters except the latest images of g’ with indications of errors ~ 0.15 mag. tc-t0 = trigger time minus image center time. Calibration was done with 3-4 bright Pan-STARRS catalog stars on our images, and no other analysis or corrections. We caution the reader that these are preliminary results, without color or other corrections, and will likely change in small measure. Please also note that times are approximate. ---------------------------------- NU = Nazarbayev University, Nur-Sultan, Kazakhstan UCB = University of California, Berkeley, USA FAI = Fesenkov Astrophysical Institute, Kazakhstan This research has been funded by the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan (Grant No. AP14870504). The NUTTelA-TAO Team acknowledges the support of the staff of the Assy-Turgen Astrophysical Observatory, Almaty, Kazakhstan, and the Fesenkov Astrophysical Institute, Almaty, Kazkhstan.
GCN 33540 table
GRB_name GRB230328B
GCN_number 33540
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 33540 SUBJECT: GRB 230328B: Nanshan/NEXT 2nd optical observation DATE: 23/03/30 01:53:10 GMT FROM: Dong Xu at NAOC/CAS T.H. Lu, S.Q. Jiang, S.Y. Fu, X. Liu (NAOC), Z.P. Zhu (NAOC, HUST), D. Xu (NAOC), X. Gao (Urumqi No.1 Senior High School), J.Z. Liu (XAO) report: We observed the field of GRB 230328B detected by Swift (Gropp et al., GCN 33527) using the NEXT-0.6m telescope located at Nanshan, Xinjiang, China. We obtained 12x300 s frames in the Sloan r-band, starting at 14:49:11 UT on 2023-03-29 (i.e., 23.9 hr after the BAT trigger). The optical afterglow (e.g., Pankov et al., GCN 33528; Belkin et al., GCN 33530; Lu et al., GCN 33534; Catapano et al., GCN 33535; Suresh et al., GCN 33536; Adami et al., GCN 33537; Gompertz et al., GCN 33538; Komesh et al., GCN 33539) is not detected in our stacked image. Preliminary photometric result is as follows: T_mid-T0 (hr) Filter Upper limit(3-sigma) 24.42 r >21.0 calibrated with the nearby PanSTARRS field and not corrected for Galactic extinction.
GCN 33541 table
GRB_name GRB230328B
GCN_number 33541
Detection_method Swift-BAT Det
ra 291.0370°
decl 80.0130°
Circular_text TITLE: GCN CIRCULAR NUMBER: 33541 SUBJECT: GRB 230328B: Swift-BAT refined analysis DATE: 23/03/30 03:44:23 GMT FROM: Tyler Parsotan at UMBC/GSFC/CRESST II C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa), D. M. Palmer (LANL), T. Parsotan (GSFC/UMBC), T. Sakamoto (AGU), M. Stamatikos (OSU) (i.e. the Swift-BAT team): Using the data set from T-240 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 230328B (trigger #1162001) (Gropp, et al., GCN Circ. 33527). The BAT ground-calculated position is RA, Dec = 291.037, 80.013 deg which is RA(J2000) = 19h 24m 08.8s Dec(J2000) = +80d 00' 45.3" with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 46%. The mask weighted light curve has a double peaked structure. The light curve does not show an early afterglow as was stated in the original GCN. T90 (15-350 keV) is 19.23 +- 3.82 sec (estimated error including systematics). The time-averaged spectrum from T-7.38 to T+25.49 sec is best fit by a power law with an exponential cutoff. This fit gives a photon index 1.22 +- 0.29, and Epeak of 99.7 +- 59.7 keV (chi squared 29.53 for 56 d.o.f.). For this model the total fluence in the 15-150 keV band is 4.3 +- 0.2 x 10^-06 erg/cm2 and the 1-sec peak flux measured from T+0.26 sec in the 15-150 keV band is 8.4 +- 0.5 ph/cm2/sec. A fit to a simple power law gives a photon index of 1.63 +- 0.07 (chi squared 35.85 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/1162001/BA/
GCN 33543 table
GRB_name GRB230328B
GCN_number 33543
Detection_method Fermi GBM Det
Circular_text TITLE: GCN CIRCULAR NUMBER: 33543 SUBJECT: GRB 230328B: GRBAlpha detection DATE: 23/03/30 11:54:37 GMT FROM: Marianna Dafcikova at Masaryk University <500025@mail.muni.cz> M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner (Masaryk U.), M. Ohno, H. Takahashi (Hiroshima U.), L. Meszaros, B. Csak (Konkoly Observatory), N. Husarikova, F. Munz , M. Topinka, M. Kolar, J.-P. Breuer, F. Hroch (Masaryk U.), T. Urbanec, M. Kasal, A. Povalac (Brno U. of Technology), J. Hudec, J. Kapus, M. Frajt (Spacemanic s.r.o), R. Laszlo, M. Koleda (Needronix s.r.o), M. Smelko, P. Hanak, P. Lipovsky (Technical U. of Kosice), G. Galgoczi (Wigner Research Center/Eotvos U.), Y. Uchida, H. Poon, H. Matake (Hiroshima U.), N. Uchida (ISAS/JAXA), T. Bozoki (Eotvos U.), G. Dalya (Eotvos U.), T. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), G. Friss (Eotvos U.), Y. Fukazawa, K. Hirose (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), K. Kapas (Eotvos U.), L. L. Kiss (Konkoly Observatory), T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), J. Takatsy (Eotvos U.), K. Torigoe (Hiroshima U.), N. Kogiso, M. Yoneyama (Osaka Metropolitan U.), M. Moritaki (U. Tokyo), T. Kano (U. Michigan) -- the GRBAlpha collaboration. The long-duration GRB 230328B (Fermi/GBM detection: GCN 33526; Swift/BAT detection: GCN 33527; AstroSat/CZTI detection: GCN 33532; GECAM-B detection: trigger no. 165) was observed by the GRBAlpha 1U CubeSat (Pal et al. 2023; arXiv:2302.10048). The detection was confirmed at the peak time 2023-03-28 14:54:49 UTC. The T90 duration measured by GRBAlpha is 8 s and the overall significance during T90 reaches 13 sigma. GRBAlpha entered the outer Van Allen radiation belt during the tail part of the burst. The light curve obtained by GRBAlpha is available here: https://grbalpha.konkoly.hu/static/share/GRB230328B_GCN.pdf All GRBAlpha detections are listed at: https://monoceros.physics.muni.cz/hea/GRBAlpha/ GRBAlpha, launched on 2021 March 22, is a demonstration mission for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). The detector of GRBAlpha consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~50 keV to ~1000 keV. To increase the duty cycle and the downlink rate, the upgrade of the on-board data acquisition software stack is in progress. The ground segment is also supported by the radio amateur community and it takes advantage of the SatNOGS network for increased data downlink volume.
GCN 33544 table
GRB_name GRB230328B
GCN_number 33544
Detection_method Konus-Wind Det
t_trigger 14:54:48.873 UTC
Circular_text TITLE: GCN CIRCULAR NUMBER: 33544 SUBJECT: Konus-Wind detection of GRB 230328B DATE: 23/03/30 14:13:25 GMT FROM: Dmitry Svinkin at Ioffe Institute D. Svinkin, D. Frederiks, M. Ulanov, A. Tsvetkova, A. Lysenko, A. Ridnaia, and T. Cline on behalf of the Konus-Wind team, report: The long-duration GRB 230328B (Fermi-GBM detection: The Fermi GBM team, GCN Circ. 33526; Swift-BAT detection: Gropp et al., GCN Circ. 33527; Markwardt et al., GCN Circ. 33541; AstroSat-CZTI detection: Waratkar et al., GCN Circ. 33532; GRBAlpha detection: Dafcikova et al., GCN Circ. 33543;) triggered Konus-Wind at T0=53688.873 s UT (14:54:48.873). The burst light curve shows a multi-peaked structure which starts at ~T0-3.3 s and has a total duration of ~12 s. The emission is seen up to ~2 MeV. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB230328_T53688/ As observed by Konus-Wind, the burst had a fluence of 7.12(-0.51,+0.58)x10^-6 erg/cm2, and a 64-ms peak flux, measured from T0+0.430 s, of 2.87(-0.77,+0.78)x10^-6 erg/cm2/s (both in the 20 keV - 10 MeV energy range). The time-averaged spectrum of the burst (measured from T0 to T0+8.448 s) is best fit in the 20 keV - 5 MeV range by a power law with exponential cutoff model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) with alpha = -1.38(-0.13,+0.14) and Ep = 151(-21,+29) keV (chi2 = 73/75 dof). Fitting by a GRB (Band) model yields the same alpha and Ep, and an upper limit on the high energy photon index: beta < -2.2 (chi2 = 74/24 dof). All the quoted errors are at the 90% confidence level. All the quoted values are preliminary.
GCN 33547 table
GRB_name GRB230328B
GCN_number 33547
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 33547 SUBJECT: GRB 230328B: 3.6m DOT multiband optical observation DATE: 23/03/31 07:49:48 GMT FROM: Amit Kumar Ror at ARIES Amit K. Ror, Rahul Gupta, S. B. Pandey, A. Ghosh, A. Aryan, and K. Misra (ARIES) report: GRB 230328B was triggered by Swift-BAT at 14:54:48 UT and Fermi-GBM at 14:54:47.43 UT on 28-03-2023 (Gropp et al. 2023 GCN 33527, Dalessi et al. 2023 GCN 33531). The prompt emission was also detected by other space-based facilities like AstroSat-CZTI (Waratkar et al. 2023, GCN 33532), GRBAlpha (Dafcikova et al. 2023, GCN 33543), and Konus-Wind (Svinkin et al. 2023, GCN 33544). We searched for extended GeV emission for a temporal window of 10 ks since the GBM trigger, based on available LAT data. However, we did not find the detection of any GeV photons, and an upper limit was obtained for an energy flux < 5.2 x 10^{-10} erg/cm2/s in the energy range 100 MeV - 100 GeV with TS < 20. We observed the field of GRB 230328B using the 3.6m Devasthal Optical Telescope located at the Devasthal observatory of the Aryabhatta Research Institute of Observational Sciences (ARIES), Nainital, India. We have taken multiple frames with an exposure time of 300 sec each in several optical passbands. We clearly detect the optical afterglow discovered by Swift-UVOT in each individual image. The estimated preliminary magnitude is as follows: Date Start_UT T_start-T0 (days) Filter Exp time (sec) magnitude ============================================================== 2023-03-28 21:51:54.44 ~0.29 R 300 sec 20.30 +/- 0.08 The magnitude quoted is not corrected for the galactic and host extinctions in the direction of the burst. Photometric calibration is performed using the standard stars from the USNO-B1 catalog. The detection of the optical afterglow is consistent with the observation of Gropp et al. 2023 (GCN 33527), Pankov et al. 2023 (GCN 33528), Belkin et al. 2023 (GCN 33530), Lu et al. 2023 (GCN 33534), Catapano et al. (33535), Suresh et al. (GCN 33536), Adami et al. (GCN 33537), Gompertz et al. (GCN 33538), Komesh et al. (GCN 33539), Lu et al. 2023 (GCN 33540) By combining our R-band magnitude with the observations of Pankov et al. 2023 (GCN 33528) and Belkin et al. 2023 (GCN 33530), we have determined the preliminary flux decay index of 0.55 +/-0.06. This circular may be cited. The 3.6m Devasthal Optical Telescope (DOT) is a recently commissioned facility in the Northern Himalayan region of India (long: 79 41 04E, lat: 29 21 40N, alt: 2540m) owned and operated by the Aryabhatta Research Institute of Observational Sciences (ARIES), Nainital ( https://www.aries.res.in). The authors of this GCN circular thankfully acknowledge the consistent support from the staff members to run and maintain the 3.6m DOT.
GCN 33549 table
GRB_name GRB230328B
GCN_number 33549
Detection_method Swift Det
Circular_text TITLE: GCN CIRCULAR NUMBER: 33549 SUBJECT: GRB 230328B: CAHA 2.2m/CAFOS detection DATE: 23/03/31 19:29:32 GMT FROM: J. F. Agui Fernandez at IAA-CSIC J. F. Agui Fernandez (IAA-CSIC), A. de Ugarte Postigo (OCA/CNRS), C. C. Thoene (ASU-CAS), M. Blazek (CAHA) , Ana Guijarro (CAHA) and S. Cikota (CAHA) report: We observed the afterglow of GR230328B (Fermi/GBM Detection: Fermi GBM Team GCN 33526, Swift detection: Gropp et al. GCN 33527) with CAFOS mounted on the 2.2 m telescope at the Calar Alto Observatory (Almeria, Spain). The observations consisted of 5 x 360 s in Rc-band and were obtained at mean epoch of 0.4717 days after the GRB. The afterglow is clearly detected with Rc = 21.00 ± 0.06 (AB) mag measured against comparison stars from the PanSTARRS catalogue.
GCN 33550 table
GRB_name GRB230328B
GCN_number 33550
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 33550 SUBJECT: GRB 230328B : GRANDMA/Kilonova-Catcher optical detection DATE: 23/03/31 20:37:22 GMT FROM: Damien Turpin at NAOC (CAS) F. Kugel (KNC), D. Turpin (CEA), S. Karpov (FZU), T. Hussenot-Desenonges (IJCLab), S. Antier (OCA/Artemis), P.A. Duverne (APC, U. Paris Cit), P. Hello (IJCLab), A. Klotz (OMP/IRAP) report on behalf of the GRANDMA/Kilonova-Catcher collaboration: The Kilonova-Catcher telescope network responded to the alert of GRB 230328B (Swift detection: Gropp et al., GCN 33527; Fermi GBM detection: Veres et al., GCN 33526). The KNC observations were taken by F. Kugel with an ARTEMIS CCD ATIK-460ex camera mounted in the 0.4-m f/2.8 reflector telescope in the Chante-Perdrix Observatory (France). The afterglow is detected in the 36x60s unfiltered coadded images at about 5.2 hours (midtime of the exposure) after the Swift/BAT trigger time. Below, we report our photometric measurement in Rc magnitude. ------------------------------------------------------------- T-T0 (day) |Exposure| Filter | Mag +/- err |Mag.Lim. (AB) ------------------------------------------------------------- 0.22172 | 36 x 60s | Rc | 20.19 +/- 0.10 | 21.4 (3 sigma) Our detection is consistent with the detections and limits previously reported in Pankov et al., GCN 33528.; Belkin, GCN 33530; Lu et al., GCN 33534; Catapano et al., GCN 33535; Suresh et al., GCN 33536.; Adami et al., GCN 33537; Gompertz et al., GCN 33538; Komesh et al., GCN 33539; Lu et al., GCN 33540; Ror et al., GCN 33547; Agui Fernandez et al., GCN 33549 The GRANDMA/Kilonova-Cacther images have been calibrated using field stars from the PanSTARRS-DR1 catalog using the STDpipe pipeline (Karpov 2022) and the ps1/r to Rc mag conversion from (Pancino et al. 2022). GRANDMA is a worldwide telescope network (grandma.ijclab.in2p3.fr) devoted to the observation of transients in the context of multi-messenger astrophysics (Antier et al. 2020 MNRAS 497, 5518). Kilonova-Catcher (KNC) is the citizen science program of GRANDMA (http://kilonovacatcher.in2p3.fr/).
GCN 33556 table
GRB_name GRB230328B
GCN_number 33556
Detection_method Swift-UVOT Det
ra 291.0078°
decl 80.0096°
Circular_text TITLE: GCN CIRCULAR NUMBER: 33556 SUBJECT: GRB 230328B: Swift/UVOT Detection DATE: 23/04/02 23:10:18 GMT FROM: Mike Siegel at PSU/Swift MOC M. H. Siegel (PSU) and J. D. Gropp (PSU) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 230328B 114 s after the BAT trigger (Gropp et al., GCN Circ. 33527). A source consistent with the XRT position (Osborne et al. GCN Circ. 33529) is detected in the initial UVOT exposures, confirming the initial optical detections (Pankov et al., GCN Circ. 33528; Catapano & Izzo, GCN Circ. 33535; Suresh et al., GCN Circ. 33536; Adami et al., GCN Circ. 33537; Komesh et al., GCN Circ. 33539). The preliminary UVOT position is: RA (J2000) = 19:24:01.88 = 291.00783 (deg.) Dec (J2000) = +80:00:34.6 = 80.00962 (deg.) with an estimated uncertainty of 0.44 arc sec. (radius, 90% confidence). Preliminary detections and 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white (fc) 114 264 147 18.38 +/- 0.05 White 5537 5735 196 20.16 +/- 0.14 white 28147 28879 713 21.88 +/- 0.32 v 655 849 39 >17.6 b 582 774 39 >18.3 u (fc) 326 576 246 19.20 +/- 0.16 w1 705 725 19 >18.5 w2 805 825 19 >18.0 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.070 in the direction of the burst (Schlegel et al. 1998).
GCN 33559 table
GRB_name GRB230328B
GCN_number 33559
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 33559 SUBJECT: GRB 230328B: Multa observatory optical afterglow observation DATE: 23/04/03 23:51:33 GMT FROM: Alexei Pozanenko at IKI, Moscow N. Pankov (HSE), L. Elenin (KIAM RAS), A. Krylov (KIAM RAS), A. Pozanenko (IKI), S. Belkin (IKI) report on behalf of GRB IKI FuN: We observed the field of GRB 230328B (Gropp et al. GCN 33527; Veres et al., GCN 33526; Dalessi et al., GCN 33531; Waratkar et al., GCN 33532; Dafcikova et al., GCN 33543; Svinkin et al. GCN 33544) with Santel-400 (0.4m) telescope of ISON-Multa observatory (Altay Republic) in Clear filter on 2023-03-28 starting on (UT) 15:16:06. We detect the optical afterglow of GRB 230328B (Gropp et al. GCN 33527; Pankov et al. GCN 33528; Belkin et al. GCN 33530; Lu et al. GCN 33534; Catapano et al. GCN 33535; Suresh et al. GCN 33536; Adami et al. GCN 33537; Gompertz et al. GCN 33538; Komesh et al. GCN 33539; Lu et al. GCN 33540; Ror et al. GCN 33547; Kugel et al. GCN 33550; Siegel et al. GCN 33556). Preliminary photometry of the afterglow source is following Date UT start t-T0 Exp. Filter OT Err. UL(3sigma) (mid, days) (s) 2023-03-28 15:16:06 0.04603 90*60 Clear 18.9 0.1 20.0 The photometry is based on nearby USNO-B1.0 (R2) stars.
GCN 33609 table
GRB_name GRB230328B
GCN_number 33609
Detection_method Swift Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 33609 SUBJECT: GRB 230328B: redshift lower limit estimating DATE: 23/04/13 00:02:47 GMT FROM: Alexei Pozanenko at IKI, Moscow P. Minaev (IKI), A. Pozanenko (IKI) report on behalf of GRB IKI FuN: We analyzed GRB 230328B detected by Swift (Gropp et al., GCN 33527), Fermi (Dalessi et al., GCN 33531), Astrosat (Waratkar et al., GCN 33532), GRBAlpha (Dafcikova et al., GCN 33543), Konus (Svinkin et al., GCN 33544). Using publicly available data of GBM/Fermi we estimate the duration T_90 = 25.7 +/- 0.5 s in (10 - 300) keV energy band. We also performed spectral analysis in a time interval of (-7, 30) s since GBM trigger, the best fit is obtained for CPL model with following parameters: E_p = 164 +/- 13 keV, alpha = -1.22 +/- 0.04. The fluence of F = (1.02 +/- 0.04)E-5 erg/cm**2 is obtained in 10 - 1000 keV energy band. Using T_90,i - EH diagram [1] we can classify the burst as type II (long) and find the minimal possible redshift value of z = 0.09. The T_90,i - EH diagram for GRB 230328B can be found in http://grb.rssi.ru/GRB230328B/GRB230328B_T90i-EH.png [1] - Minaev, Pozanenko, MNRAS, 492, 1919, 2020
GCN 34141 table
GRB_name GRB230328B
GCN_number 34141
Detection_method Konus-Wind Det
Circular_text TITLE: GCN CIRCULAR NUMBER: 34141 SUBJECT: GRB 230328B: LBT detection of the likely host galaxy DATE: 23/07/04 14:14:34 GMT FROM: Andrea Rossi at INAF A. Rossi, E. Maiorano, and E. Palazzi (INAF-OAS) report on behalf of the CIBO collaboration: We observed the field of the long GRB 230328B detected by Fermi-GBM (Fermi GBM Team, GCN 33526; Dalessi et al., GCN 33531), Swift-BAT (Gropp et al., GCN 33527), AstroSat-CZTI (Waratkar et al., GCN 33532), GRBAlpha (Dafcikova et al., GCN 33543), and Konus-Wind (Svinkin et al., GCN 33544). We obtained 20 min of g'- and r'-band imaging with the LBC camera mounted on LBT (Mt Graham, AZ, USA) on 2023-06-23, ~3 months after the burst trigger. Observations were performed under mediocre weather conditions with a strong SW wind and thus an average seeing of ~2". At the location of the optical afterglow (Pankov et al., GCN 33528; Belkin et al., GCN 33530; Lu et al., GCN 33534; Catapano et al., GCN 33535; Suresh et al., GCN 33536; Adami et al., GCN 33537; Gompertz et al., GCN 33538; Komesh et al., GCN 33539; Kumar et al., GCN 33547; Kugel et al., GCN 33550; Siegel et al., 33556; Pozanenko et al., GCN 33559), we detect a faint source which is likely the GRB host galaxy. We measure the following AB magnitudes: g 24.2 +- 0.3 r 23.8 +- 0.2 calibrated against PanSTARRS field stars, and not corrected for the foreground Galactic extinction. We acknowledge the excellent support from the LBTO and LBT-INAF staff, particularly D. Thompson, D. Gonzalez Huerta, F. Cusano and D. Paris, in obtaining these observations.