GRB250615A

This page lists all entries on GRB250615A in GRBweb

Summary Swift GCN 40736 GCN 40737 GCN 40739 GCN 40743 GCN 40745 GCN 40747 GCN 40748 GCN 40749 GCN 40752 GCN 40759 GCN 40765 GCN 40785

Summary table
Variable Value Source
T0 22:25:19.590 UTC GCN_circulars,Swift Det
ra 290.3857° Swift
decl 4.6851° Swift
pos_error 2.98e-04° Swift
GBM_located False
mjd 60841.934254513886 GCN_circulars,Swift Det
Swift table
GRB_name GRB250615A
t_trigger 22:25:19.590 UTC
ra 290.3857°
decl 4.6851°
pos_error 2.98e-04°
GCN 40736 table
GRB_name GRB250615A
GCN_number 40736
Detection_method Swift Det
t_trigger 22:25:19.590 UTC
ra 290.3440°
decl 4.6720°
Circular_text TITLE: GCN CIRCULAR NUMBER: 40736 SUBJECT: GRB 250615A: Swift detection of a burst DATE: 25/06/15 22:44:24 GMT FROM: Simone Dichiara at Pennsylvania State University S. Dichiara (PSU), J. J. DeLaunay (PSU), R. Gupta (NASA GSFC) and T. Sakamoto (AGU) report on behalf of the Neil Gehrels Swift Observatory Team: At 22:25:19.59 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 250615A (trigger=1324646). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 290.344, +4.672 which is RA(J2000) = 19h 21m 23s Dec(J2000) = +04d 40' 21" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a complex structure with a duration of about 55 sec. The peak count rate was ~5000 counts/sec (15-350 keV), at ~1 sec after the trigger. The XRT began observing the field at 22:26:46.4 UT, 86.9 seconds after the BAT trigger. Using promptly downlinked data we find a bright, fading, uncatalogued X-ray source located at RA, Dec 290.38466, 4.68467 which is equivalent to: RA(J2000) = 19h 21m 32.32s Dec(J2000) = +04d 41' 04.8" with an uncertainty of 3.6 arcseconds (radius, 90% containment). This location is 152 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 does not constrain the column density. The initial flux in the 2.5 s image was 9.89e-10 erg cm^-2 s^-1 (0.2-10 keV). UVOT took a finding chart exposure of 250 seconds with the U filter starting 152 seconds after the BAT trigger. No credible afterglow candidate has been found in the initial data products. Results from the 2.7'x2.7' sub-image are not available at this time. 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 18.0 mag. No correction has been made for the large, but uncertain, extinction expected. Burst Advocate for this burst is S. Dichiara (sbd5667 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 40737 table
GRB_name GRB250615A
GCN_number 40737
Detection_method Swift-XRT Other
ra 290.3856°
decl 4.6853°
Circular_text TITLE: GCN CIRCULAR NUMBER: 40737 SUBJECT: GRB 250615A: Prompt enhanced Swift-XRT position DATE: 25/06/15 23:00:07 GMT FROM: Phil Evans at U of Leicester P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team: Using 1.0 ks of promptly downlinked XRT event data for GRB 250615A, we find an enhanced XRT position of the afterglow: RA, Dec: 290.38555, 4.68527 which is equivalent to: RA (J2000) = 19 21 32.53 Dec (J2000) = +04 41 07.0 with an uncertainty of 2.0 arcseconds (radius, 90% confidence). Analysis of the promptly available data is online at http://www.swift.ac.uk/sper/1324646. 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 40739 table
GRB_name GRB250615A
GCN_number 40739
Detection_method Swift-XRT Det
ra 290.3856°
decl 4.6852°
Circular_text TITLE: GCN CIRCULAR NUMBER: 40739 SUBJECT: GRB 250615A: Enhanced Swift-XRT position DATE: 25/06/16 02:49:06 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 1622 s of XRT Photon Counting mode data and 1 UVOT images for GRB 250615A, 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 = 290.38565, +4.68515 which is equivalent to: RA (J2000): 19h 21m 32.56s Dec (J2000): +04d 41' 06.5" with an uncertainty of 2.3 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 40743 table
GRB_name GRB250615A
GCN_number 40743
Detection_method Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 40743 SUBJECT: EP250615a/GRB 250615A: EP-WXT detection of a fast X-ray transient DATE: 25/06/16 09:31:10 GMT FROM: EP Team at NAOC/CAS G. J. Yang, M. J. Liu (NAO, CAS), Y. Q. Zhao (USTC,PRIC), Y. P. Zhou (NJU), X. L. Chen (YNU), Q. Y. Wu, C. C. Jin (NAO,CAS) on behalf of the Einstein Probe team: We report on the detection of a fast X-ray transient, designated EP250615a, by the Wide-field X-ray Telescope (WXT) on board the Einstein Probe (EP) mission. The transient event started at 2025-06-15T22:25:17 (UTC). The position of the source is R.A. = 290.379 deg, DEC = 4.678 deg (J2000) with an uncertainty of 2.181 arcmin in radius (90% C.L. statistical and systematic). The transient event lasts for more than 50 seconds. The lightcurve of the transient observed by the WXT exhibits a rapid brightening profile. The average 0.5-4 keV spectrum can be fitted by an absorbed power law with a photon index of 2.2 (+1.5/-1.4) with a column density value of 2.1 (+1.7/-1.6) x 10^22 cm^-2. The derived average unabsorbed 0.5-4 keV flux is 1.0 (+4.3/-0.6) x 10^-8 erg/s/cm^2. The peak flux is around 6.3 x 10^-7 erg/s/cm^2. The uncertainties are at the 90% confidence level for the above parameters. The trigger time and position of this X-ray transient are consistent with that of GRB 250615A (GCN 40736, GCN 40737, GCN 40739). Launched on January 9, 2024, EP is a space X-ray observatory to monitor the soft X-ray sky with X-ray follow-up capability (Yuan et al. 2022, Handbook of X-ray and Gamma-ray Astrophysics).
GCN 40745 table
GRB_name GRB250615A
GCN_number 40745
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 40745 SUBJECT: GRB 250615A: Swift-XRT refined Analysis DATE: 25/06/16 10:56:50 GMT FROM: Phil Evans at U of Leicester D.N. Burrows (PSU), M.A. Williams (PSU), S. Dichiara (PSU), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), M.G. Bernardini (INAF-OAB), E. Ambrosi (INAF-IASFPA) , M. Capalbi (INAF-OAR) and P.A. Evans report on behalf of the Swift-XRT team: We have analysed 6.2 ks of XRT data for GRB 250615A, from 93 s to 40.3 ks after the trigger. The data comprise 106 s in Windowed Timing (WT) mode with the remainder in Photon Counting (PC) mode. The light curve can be modelled with a power-law decay with a decay index of alpha=1.62 (+0.07, -0.06). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.62 (+0.27, -0.26). The best-fitting absorption column is 2.4 (+0.6, -0.5) x 10^22 cm^-2, in excess of the Galactic value of 5.5 x 10^21 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 2.0 (+0.4, -0.3) and a best-fitting absorption column of 2.4 (+0.7, -0.6) x 10^22 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 6.7 x 10^-11 (1.5 x 10^-10) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 2.4 (+0.7, -0.6) x 10^22 cm^-2 Galactic foreground: 5.5 x 10^21 cm^-2 Excess significance: 5.3 sigma Photon index: 2.0 (+0.4, -0.3) If the light curve continues to decay with a power-law decay index of 1.62, the count rate at T+24 hours will be 2.2 x 10^-4 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.5 x 10^-14 (3.3 x 10^-14) erg cm^-2 s^-1. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/01324646. This circular is an official product of the Swift-XRT team.
GCN 40747 table
GRB_name GRB250615A
GCN_number 40747
Detection_method Swift-UVOT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 40747 SUBJECT: GRB 250615A: Swift/UVOT Upper Limits DATE: 25/06/16 11:38:35 GMT FROM: Paul Kuin at MSSL N.P.M.Kuin (UCL/MSSL) and S. Dichiara (PSU) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 250615A 152 s after the BAT trigger (Dichiara et al., GCN Circ. 40736). No optical afterglow consistent with the enhanced XRT position (Goad et al., GCN Circ. 40739) 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 u_FC 152 402 246 >19.8 white 432 1722 284 >21.0 v 483 1772 156 >19.5 b 408 1697 136 >20.7 u 152 1672 363 >20.0 w1 532 1821 136 >19.5 w2 804 1747 78 >19.2 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 1.165 in the direction of the burst (Schlegel et al. 1998).
GCN 40748 table
GRB_name GRB250615A
GCN_number 40748
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 40748 SUBJECT: GRB 250615A: DDOTI Optical Upper Limit DATE: 25/06/16 12:02:03 GMT FROM: Rosa L. Becerra at Tor Vergata, Roma Rosa L. Becerra (U Roma), Alan M. Watson (UNAM), Sahil Atri (U Roma), Camila Angulo Valdez (UNAM), Nat Butler (ASU), Simone Dichiara (Penn State University), Tsvetelina Dimitrova (ASU), Alexander Kutyrev (GSFC/UMD), William H. Lee (UNAM), Océlotl López (UNAM), Margarita Pereyra (UNAM) and Eleonora Troja (U Roma) report: We observed the field of GRB 250615A detected by Swift (Dichiara et al., GCN Circ. 40736) with the DDOTI/OAN wide-field imager at the Observatorio Astronómico Nacional on Sierra San Pedro Mártir (http://ddoti.astroscu.unam.mx) on the night of 2025-06-16 UTC. DDOTI observed the enhanced Swift-XRT position (Goad et al., GCN Circ. 40739) from 05:18 UTC to 09:55 UTC (from T+6.9 h to T+ 11.5 h after the trigger), obtaining a total exposure of 1.6 hours, alternating with other scientific programs. Comparing our observations to Pan-STARRS PS1 DR2 catalogues, we detect no uncatalogued fading sources within the observed field down to a 3-sigma limiting AB magnitude of: w >19.3 This upper limit is consistent with the non-detection reported by Swift/UVOT (Kuin et al., GCN Circ. 40747). This value is not corrected for Galactic extinction, which is significant due to the burst’s proximity to the Galactic plane. We thank the staff of the Observatorio Astronómico Nacional on the Sierra of San Pedro Mártir.
GCN 40749 table
GRB_name GRB250615A
GCN_number 40749
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 40749 SUBJECT: GRB 250615A: COLIBRÍ optical upper limit DATE: 25/06/16 15:32:51 GMT FROM: Francesco at Aix-Marseille Université, CPPM/CNRS Francesco Magnani (CPPM), Margarita Pereyra (UNAM), Stéphane Basa (UAR Pytheas), William H. Lee (UNAM), Alan M. Watson (UNAM), Fredd Alvarez (UNAM), Jean-Luc Atteia (IRAP), Camila Angulo (UNAM), Dalya Akl (AUS), Sarah Antier (OCA), Rosa L. Becerra (U Roma), Nathaniel R. Butler (ASU) , Damien Dornic (CPPM), Jean-Grégoire Ducoin (CPPM), Francis Fortin (IRAP), Leonardo García García (UNAM), Ramandeep Gill (UNAM), Noémie Globus (UNAM), Kin Ocelotl López (UNAM), Diego López-Cámara (UNAM), Enrique Moreno Méndez (UNAM), Ny Avo Rakotondrainibe (LAM), Benjamin Schneider (LAM) and Antonio de Ugarte Postigo (LAM): We imaged the field of the Swift GRB 250615A (Dichiara et al., GCN Circ. 40736) using the DDRAGO wide-field imager on the COLIBRÍ telescope. We observed from 2025-06-16 08:40 to 2025-06-16 10:46 UTC (from 10.3 to 12.3 hours after the trigger) and obtained 96 minutes of exposure in the i filter. The data were reduced and coadded with the COLIBRÍ pipeline and analysed with STDWeb/STDPipe (Karpov 2025). The photometry was calibrated using nearby stars from the PanSTARRS DR1 catalog, is in the AB system, and is not corrected for Galactic extinction. In our stacked image, we do not detect any new source at the enhanced Swift-XRT position (Goad et al., GCN Circ. 40739) down to a 3-sigma limiting AB magnitude of: i > 22.8 Our upper limit is consistent with the non-detection reported by Swift/UVOT (Kuin et al., GCN Circ. 40747) and DDOTI (Becerra et al., GCN Circ. 40748). We thank the staff of the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir and the COLIBRÍ and DDRAGO engineering teams. COLIBRÍ is an astronomical observatory developed and operated jointly by France (AMU, CNES and CNRS) and Mexico (UNAM and SECIHTI). It is located at the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir, Baja California, Mexico.
GCN 40752 table
GRB_name GRB250615A
GCN_number 40752
Detection_method AstroSat CZTI
Circular_text TITLE: GCN CIRCULAR NUMBER: 40752 SUBJECT: GRB 250615A / EP250615a: AstroSat CZTI detection DATE: 25/06/17 05:50:31 GMT FROM: Gaurav Waratkar at IIT Bombay M. Tembhurnikar (IUCAA), G. Waratkar (IITB), Harsha K. H. (IUCAA), 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 a long duration GRB 250615A / EP250615a which was also detected by Swift/BAT (Dichiara et al., GCN Circ. 40736) and Einstein Probe/WXT (Yang et al., GCN Circ. 40743). The burst location was at an angle of 84 deg from the pointing axis of AstroSat CZTI. The source was clearly detected in the CZT detectors in the 20-200 keV energy range. The light curve peaks at 2025-06-15 22:25:17.50 UTC. The measured peak count rate associated with the burst is 99 (+31, -11) counts/s above the background in the combined data of two quadrants (out of four), with a total of 983 (+231, -222) counts. The local mean background count rate was 155 (+1, -2) counts/s. Using cumulative rates, we measure a T90 of 22 (+15, -5) s. The source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2025-06-15 22:25:22.52 UTC. The measured peak count rate associated with the burst is 490 (+70, -50) counts/s above the background in the combined data of all quadrants, with a total of 7176 (+826, -898) counts. The local mean background count rate was 1329 (+7, -8) counts/s. We measure a T90 of 34 (+6, -10) 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 40759 table
GRB_name GRB250615A
GCN_number 40759
Detection_method Swift-BAT Det
Circular_text TITLE: GCN CIRCULAR NUMBER: 40759 SUBJECT: GRB 250615A: Calapai Observatory, Massa S. Giorgio (Messina), upper limit DATE: 25/06/17 16:55:47 GMT FROM: Giovanni Calapai at Calapai Astronomical Observatory, Massa S. Giorgio, Messina, Italy Giovanni Calapai at Calapai Astronomical Observatory, Massa S. Giorgio, (Messina) Italy Member of: GRB/UAI Gamma Ray Burst Section of Unione Astrofili Italiani. Report: We imaged the field of GRB 250615A detected by Swift/BAT (Dichiara et al. GCN 40736), with the 11 inches Schmidt-Cassegrain (Celestron 11) telescope F/D=6,3. The observations were started at 2025-06-15 23:21:59 UT (approximately 56 minutes after burst) stacking a set of unfiltered CCD image. We co-added 180 exposures of 60 sec each. Start T0+ End T0+ CR lim 0.94 hour 4.33 hour 19.6 We did not found any optical uncatalogued object within the Swift error circle. Magnitudes were estimated with the PanSTARRS cat. and are not corrected for galactic dust extinction. Our upper limit is consistent with other observations reported by Kuin et al. (GCN 40747), Becerra et al. (GCN 40748), Magnani et al. (GCN 40749). The message may be cited.
GCN 40765 table
GRB_name GRB250615A
GCN_number 40765
Detection_method Swift-BAT Det
ra 290.3840°
decl 4.6790°
Circular_text TITLE: GCN CIRCULAR NUMBER: 40765 SUBJECT: GRB 250615A: Swift-BAT refined analysis DATE: 25/06/18 02:48:55 GMT FROM: Takanori Sakamoto at AGU S. D. Barthelmy (GSFC), S. Dichiara (PSU), R. Gupta (GSFC), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa), C. B. Markwardt (GSFC), M. J. Moss (GSFC), D. M. Palmer (LANL), T. Parsotan (GSFC), D. Sadaula (GSFC/UMBC), T. Sakamoto (AGU) (i.e. the Swift-BAT team): Using the data set from T-239 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 250615A (trigger #1324646) (Dichiara, et al., GCN Circ. 40736). The BAT ground-calculated position is RA, Dec = 290.384, 4.679 deg which is RA(J2000) = 19h 21m 32.1s Dec(J2000) = +04d 40' 44.0" with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 56%. The mask-weighted light curve shows a complex structure that starts at T-5 sec, peaks at T+5 sec, and ends at T+77 sec. T90 (15-350 keV) is 52.5 +- 10.3 sec (estimated error including systematics). The time-averaged spectrum from -5.2 to 77.3 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.22 +- 0.08. The fluence in the 15-150 keV band is 3.8 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+3.29 sec in the 15-150 keV band is 4.1 +- 0.3 ph/cm2/sec. All the quoted errors are at the 90% confidence level. The results of the batgrbproduct analysis are available at https://swift.gsfc.nasa.gov/results/batgrbcat/BAT_refined_circular/1324646
GCN 40785 table
GRB_name GRB250615A
GCN_number 40785
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 40785 SUBJECT: GRB 250615A: Kilonova-Catcher optical upper limits DATE: 25/06/19 21:45:50 GMT FROM: Damien Turpin at CEA-Saclay D. Turpin (CEA-Saclay/Irfu), R. Hellot, M. Freeberg (KNC), C. Andrade(UMN), M. Pillas (ULiege), M. Tanasan (NARIT), S. Antier (OCA/IJCLAB) on behalf of the GRANDMA/Kilonova-Catcher collaboration: We observed the field of GRB 250615A (Dichiara et al., GCN 40736) detected by Swift/BAT with the GRANDMA citizen science project Kilonova-catcher (KNC). Our observations were performed with the TEC160FL telescope operated by M. Freeberg and a CDK17 telescope located at AITP San Pedro Chile Observatory operated by R. Hellot. Our observations started at TGRB+7.6hr. In our stacked frames, subtracted from the PanSTARRS DR2 template image, we do not detect any optical counterpart inside the Swift/XRT refined position (Goad et al., GCN 40739). We report our follow-up results in the table below: +---------------+-------------+---------+---------------------+--------------+ | Tmid-TGRB (hr)| Exp (s) | Filter | Magnitude | Instrument | +===============+=============+=========+=====================+==============+ | 7.9 | 6 x 300s | r (AB) | 20.1 (U.L., 5sigma) | TEC160FL | | 8.1 | 11 x 300s | g (AB) | 20.8 (U.L., 5sigma) | CDK17-AITP | | 8.5 | 6 x 300s | g (AB) | 20.4 (U.L., 5sigma) | TEC160FL | | 9.0 | 6 x 300s | i (AB) | 19.2 (U.L., 5sigma) | TEC160FL | | 9.6 | 11 x 300s | r (AB) | 20.2 (U.L., 5sigma) | CDK17-AITP | +---------------+-------------+---------+---------------------+--------------+ All the data have been reduced by a single data processing pipeline, STDPipe (Karpov et al., 2022). Images obtained with the sloan images were calibrated using the PanSTARRS DR1 catalog. We use the SkyPortal application (skyportal.io) to monitor our observational campaign (Coughlin et al. 2023). 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/).