July 2025 - vsnet-grb-info - ooruri.kusastro.kyoto-u.ac.jp

[vsnet-grb-info 39140] GRB 250706B/C: 7DT Follow-up Observations
by GCN Circulars 14 Jul '25

14 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41087 SUBJECT: GRB 250706B/C: 7DT Follow-up Observations DATE: 25/07/14 06:58:11 GMT FROM: Mankeun Jeong <jmk5040(a)gmail.com> Mankeun Jeong (SNU/SNUARC), Myungshin Im (SNU/SNUARC), Hyeonho Choi (SNU/SNUARC), and Seo-Won Chang (SNU/SNUARC) report on behalf of the 7-Dimensional Telescope collaboration We observed the field of GRB 250706B/C (Palmerio et al., GCN 40989; Zhu et al., GCN 40991; Frederiks et al., GCN 41013; Longo et al., GCN 41019) using the 7-Dimensional Telescope (7DT). Observations were conducted on 2025 July 8 in multiple broadband and medium-band filters. We performed forced photometry at the position of the UVOT optical counterpart (GCN 41015; RA = 02:44:53.43, Dec = −50:03:40.2, J2000), using a coadded image from all filters for source detection. Photometric calibration was performed using Gaia XP synthetic photometry (Gaia Collaboration et al. 2022). We report a marginal detection only in the i-band, with a magnitude of i = 19.68±0.38 AB mag at T-T0 ≈ 1.84 days. The following table lists our photometric measurements (AB magnitudes). For non-detections, we provide 5σ upper limits: Filter Mag (AB) Exp(s) UT Date-Obs T−T₀ (days) ----------------------------------------------------------------------- g >19.90 300 2025-07-08 07:21:36 1.842 r >19.88 300 2025-07-08 07:26:58 1.846 i 19.68 ± 0.38 1200 2025-07-08 07:38:17 1.841 m400 >18.19 300 2025-07-08 07:27:01 1.846 m450 >18.85 300 2025-07-08 07:21:33 1.842 m475 >18.94 300 2025-07-08 07:26:58 1.846 m550 >18.65 300 2025-07-08 07:21:40 1.842 m575 >18.69 300 2025-07-08 07:27:08 1.846 m600 >18.71 300 2025-07-08 07:21:41 1.842 m625 >18.56 300 2025-07-08 07:27:15 1.846 m650 >18.81 300 2025-07-08 07:21:34 1.842 m675 >18.78 300 2025-07-08 07:26:57 1.846 m700 >18.62 300 2025-07-08 07:21:29 1.841 m725 >18.46 300 2025-07-08 07:26:50 1.846 m750 >18.31 300 2025-07-08 07:21:36 1.842 m775 >17.94 300 2025-07-08 07:26:59 1.846 m800 >17.70 300 2025-07-08 07:21:43 1.842 m825 >17.63 300 2025-07-08 07:27:13 1.846 m850 >17.06 300 2025-07-08 07:21:31 1.842 m875 >16.84 300 2025-07-08 07:21:37 1.842 View this GCN Circular online at https://gcn.nasa.gov/circulars/41087. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39139] GRB 250713A: Swift-XRT observations
by GCN Circulars 14 Jul '25

14 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41086 SUBJECT: GRB 250713A: Swift-XRT observations DATE: 25/07/14 05:58:35 GMT FROM: Phil Evans at U of Leicester <pae9(a)star.le.ac.uk> P.A. Evans (U. Leicester), J.A. Kennea (PSU), E. Ambrosi (INAF-IASFPA) , A.P. Beardmore (U. Leicester), M.G. Bernardini (INAF-OAB), R. Brivio (INAF-OAB), D.N. Burrows (PSU), S. Campana (INAF-OAB), M. Capalbi (INAF-OAR), A. D'Ai (INAF-IASFPA), P. D'Avanzo (INAF-OAB), V. D'Elia (SSDC & INAF-OAR), S. Dichiara (PSU), M. Ferro (INAF-OAB), A. Melandri (INAF-OAR), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), M. Perri (SSDC & INAF-OAR), C. Salvaggio (INAF-OAB), T. Sbarrato (INAF-OAB), B. Sbarufatti (INAF-OAB), M.A. Williams (PSU) report on behalf of the Swift-XRT team: Swift-XRT has performed follow-up observations of the SVOM/ECLAIRs-detected source GRB 250713A, collecting 2.0 ks of Photon Counting (PC) mode data between T0+429 s and T0+6.4 ks after the trigger. We have detected 1 source. This has been automatically classified as an uncatalogued X-ray source. Uncatalogued X-ray sources -------------------------- Source 1 (SWIFT J222820.3+385214): ================================== RA (J2000.0): 337.0847 = 22h 28m 20.33s Dec (J2000.0): +38.8706 = +38d 52' 14.2" Error: 7.0 (arcsec, radius, 90% confidence). Detect flag: GOOD Distance: 8.2 arcmin from the SVOM/ECLAIRs position. Mean rate: (7.7 [+2.8, -2.3])e-3 ct s^-1 Mean flux: (2.94 [+1.07, -0.88])e-13 erg cm^-2 s^-1 Peak rate: (7.7 [+2.8, -2.3])e-3 ct s^-1 Peak flux: (2.94 [+1.07, -0.88])e-13 erg cm^-2 s^-1 ECF: 3.84e-11 erg cm^-2 ct^-1, assuming NH=1.27e+21 cm^-2, gamma=1.63; determined from a spectral fit. XMM UL: 2.2e-12 erg cm^-2 s^-1, (0.3-10 keV) so the source is 19.2-sigma above this 3-sigma upper limit. There is no evidence for fading. This source is not spatially consistent with any of those detected by EP-FXT (Circ. 41085). All fluxes are 0.3-10 keV, observed. For all flux conversions and comparisons with catalogues and upper limits from other missions, we assumed a power-law spectrum with NH=3x10^20 cm^-2 and photon index (Gamma)=1.7 unless otherwise stated. The results of the XRT-team automatic analysis of the XRT observations, including a position-specific upper limit calculator, are available at https://www.swift.ac.uk/SVOM. This circular is an officicial product of the Swift-XRT team. View this GCN Circular online at https://gcn.nasa.gov/circulars/41086. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39138] GRB 250713A: EP-FXT counterpart detection
by GCN Circulars 14 Jul '25

14 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41085 SUBJECT: GRB 250713A: EP-FXT counterpart detection DATE: 25/07/14 03:06:19 GMT FROM: EP Team at NAOC/CAS <ep_ta(a)bao.ac.cn> Y. F. Liang (PMO, CAS), M. H. Zhang (NAO, CAS), C. Y. Dai (NJU), Y. Liu (NAO, CAS) on behalf of the Einstein Probe (EP) team: EP-FXT performed a follow-up observation of the SVOM/ECLAIRs-detected burst GRB 250713A (SVOM/sb25071320) at 2025-07-13T18:52:11 (UTC), about 2 hours after the SVOM/ECLAIRs trigger, with an exposure time of 4919s. Five uncatalogued sources are detected within the ECLAIRs error circle, among which Source 2 is spatially consistent with the candidate counterpart detected by SVOM/MXT (Maggi et al. GCN #41078). Preliminary analysis on these source are automatically conducted, and the details are listed as follows. Source 1: EPF_J222746.7+384738 RA (J2000): 336.9445 Dec (J2000): 38.7939 Flux: 2.68 x 10^-13 erg/s/cm^2 (observed, 0.5-10 kev) Flux_err: 4.65 x 10^-14 erg/s/cm^2 (1 sigma) Source 2: EPF_J222734.0+384613 RA (J2000): 336.8919 Dec (J2000): 38.7702 Flux: 1.05 x 10^-13 erg/s/cm^2 (observed, 0.5-10 kev) Flux_err: 4.09 x 10^-14 erg/s/cm^2 (1 sigma) Note: This source is spatially consistent with the candidate counterpart detected by SVOM/MXT. Source 3: EPF_J222734.3+384800 RA (J2000): 336.8931 Dec (J2000): 38.8000 Flux: 1.39 x 10^-13 erg/s/cm^2 (observed, 0.5-10 kev) Flux_err: 3.05 x 10^-14 erg/s/cm^2 (1 sigma) Source 4: EPF_J222729.6+384709 RA (J2000): 336.8733 Dec (J2000): 38.7859 Flux: 9.13 x 10^-13 erg/s/cm^2 (observed, 0.5-10 kev) Flux_err: 2.37 x 10^-13 erg/s/cm^2 (1 sigma) Source 5: EPF_J222815.4+384825 RA (J2000): 337.0641 Dec (J2000): 38.8070 Flux: 8.94 x 10^-14 erg/s/cm^2 (observed, 0.5-10 kev) Flux_err: 3.54 x 10^-14 erg/s/cm^2 (1 sigma) The Source 1, 2, and 3 were detected by both FXT-A and FXT-B, while Source 4 and 5 were detected only by FXT-B. The positional uncertainty of the sources are about 10 arcsec in radius (90% C.L. statistical and systematic). 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). View this GCN Circular online at https://gcn.nasa.gov/circulars/41085. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39137] EP250711a: COLIBRÍ continuous optical observations
by GCN Circulars 13 Jul '25

13 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41084 SUBJECT: EP250711a: COLIBRÍ continuous optical observations DATE: 25/07/13 21:34:30 GMT FROM: Rosa L. Becerra at Tor Vergata, Roma <rosa.becerra(a)roma2.infn.it> Rosa L. Becerra (U Roma), Alan M. Watson (UNAM), Nikos Mandarakas (LAM), Stéphane Basa (UAR Pytheas), William H. Lee (UNAM), Jean-Luc Atteia (IRAP), Fredd Alvarez (UNAM), Camila Angulo (UNAM), Dalya Akl (AUS), Sarah Antier (OCA), 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), Francesco Magnani (CPPM), Enrique Moreno Méndez (UNAM), Margarita Pereyra (UNAM), Ny Avo Rakotondrainibe (LAM), Benjamin Schneider (LAM) and Antonio de Ugarte Postigo (LAM): We continued the follow-up campaign of EP250711a (Wang et al., GCN Circ. 41070) using the DDRAGO wide-field imager on the COLIBRÍ telescope. Observations were conducted on 2025-07-13 from 04:57 to 10:32 UTC (35.8 to 41.4 hours after the trigger), obtaining 61 minutes of exposure in each of the g, r and i filters. 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. We measure preliminary magnitudes of: g = 23.02 +/- 0.24 r = 22.78 +/- 0.22 i = 21.64 +/- 0.11 Compared with the value reported in Becerra et al. (GCN Circ. 41073), we estimate a temporal decay index of ~0.9. 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. View this GCN Circular online at https://gcn.nasa.gov/circulars/41084. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39136] GRB 250706A: Swift-BAT refined analysis
by GCN Circulars 13 Jul '25

13 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41083 SUBJECT: GRB 250706A: Swift-BAT refined analysis DATE: 25/07/13 21:01:31 GMT FROM: Takanori Sakamoto at AGU <tsakamoto(a)phys.aoyama.ac.jp> D. M. Palmer (LANL), S. D. Barthelmy (GSFC), R. Gupta (GSFC), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa), C. B. Markwardt (GSFC), M. J. Moss (GSFC), T. Parsotan (GSFC), D. Sadaula (GSFC/UMBC), T. Sakamoto (AGU) (i.e. the Swift-BAT team): Using the data set from T-240 to T+962 sec from the recent telemetry downlink, we report further analysis of BAT GRB 250706A (trigger #1330958) (Moss, et al., GCN Circ. 40988). The BAT ground-calculated position is RA, Dec = 284.011, 32.327 deg which is RA(J2000) = 18h 56m 02.7s Dec(J2000) = +32d 19' 36.8" with an uncertainty of 1.7 arcmin, (radius, sys+stat, 90% containment). The partial coding was 26%. The mask-weighted light curve shows a single-peak structure that starts at ~T-1 s, peaks at ~T+2 s, and ends at ~T+40 s. T90 (15-350 keV) is 31.9 +- 7.2 sec (estimated error including systematics). The time-averaged spectrum from T0 to T+40 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.34 +- 0.17. The fluence in the 15-150 keV band is 1.6 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+1.93 sec in the 15-150 keV band is 1.3 +- 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/1330958 View this GCN Circular online at https://gcn.nasa.gov/circulars/41083. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39135] GRB 250702F: Swift-BAT refined analysis
by GCN Circulars 13 Jul '25

13 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41082 SUBJECT: GRB 250702F: Swift-BAT refined analysis DATE: 25/07/13 21:00:20 GMT FROM: Takanori Sakamoto at AGU <tsakamoto(a)phys.aoyama.ac.jp> M. J. Moss (GSFC), S. D. Barthelmy (GSFC), R. Gupta (GSFC), N. J. Klingler (GSFC/UMBC/CRESSTII) H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa), C. B. Markwardt (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 250702F (trigger #1329888) (Klingler, et al., GCN Circ. 40894). The BAT ground-calculated position is RA, Dec = 212.942, 16.739 deg which is RA(J2000) = 14h 11m 46.1s Dec(J2000) = +16d 44' 20.6" with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 81%. The mask-weighted light curve shows a complex structure that starts at ~T-3 s, peaks at ~T+38 s, and ends at ~T+80 s. T90 (15-350 keV) is 63.7 +- 12.5 sec (estimated error including systematics). The time-averaged spectrum from T-29.13 to T+76.44 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.49 +- 0.06. The fluence in the 15-150 keV band is 4.8 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+37.35 sec in the 15-150 keV band is 5.1 +- 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/1329888 View this GCN Circular online at https://gcn.nasa.gov/circulars/41082. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39134] GRB 250628A: Swift-BAT refined analysis
by GCN Circulars 13 Jul '25

13 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41081 SUBJECT: GRB 250628A: Swift-BAT refined analysis DATE: 25/07/13 20:59:21 GMT FROM: Takanori Sakamoto at AGU <tsakamoto(a)phys.aoyama.ac.jp> C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC), M. Ferro (INAF-OAB), R. Gupta (GSFC), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa), 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-240 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 250628A (trigger #1328546) (Ferro, et al., GCN Circ. 40853). The BAT ground-calculated position is RA, Dec = 38.539, -38.082 deg which is RA(J2000) = 02h 34m 09.3s Dec(J2000) = -38d 04' 54.3" with an uncertainty of 1.5 arcmin, (radius, sys+stat, 90% containment). The partial coding was 51%. The mask-weighted light curve shows a double-peak structure that starts at ~T-9 s, peaks at ~T+1 s, and ends at ~T+70 s. T90 (15-350 keV) is 64 +- 11 sec (estimated error including systematics). The time-averaged spectrum from T-9.42 to T+68.56 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.99 +- 0.12. The fluence in the 15-150 keV band is 1.9 +- 0.1 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T-0.10 sec in the 15-150 keV band is 1.2 +- 0.2 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/1328546 View this GCN Circular online at https://gcn.nasa.gov/circulars/41081. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39133] LIGO/Virgo/KAGRA S250712cd: Updated Sky localization
by GCN Circulars 13 Jul '25

13 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41080 SUBJECT: LIGO/Virgo/KAGRA S250712cd: Updated Sky localization DATE: 25/07/13 19:39:42 GMT FROM: Sylvia Biscoveanu at Northwestern CIERA <sylvia.biscoveanu(a)ligo.org> The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report: We have conducted further analysis of the LIGO Hanford Observatory (H1), LIGO Livingston Observatory (L1), and Virgo Observatory (V1) data around the time of the compact binary merger (CBC) candidate S250712cd (GCN Circular 41075). Parameter estimation has been performed using Bilby [1] and a new sky map, Bilby.multiorder.fits,0, distributed via GCN and SCiMMA notices, is available for retrieval from the GraceDB event page: https://gracedb.ligo.org/superevents/S250712cd For the Bilby.multiorder.fits,0 sky map, the 90% credible region is well fit by an ellipse with an area of 180 deg2 described by the following DS9 region (right ascension, declination, semi-major axis, semi-minor axis, position angle of the semi-minor axis): icrs; ellipse(19h24m, +55d04m, 10.93d, 5.26d, 101.96d) Marginalized over the whole sky, the a posteriori luminosity distance estimate is 2439 +/- 870 Mpc (a posteriori mean +/- standard deviation). For further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide https://emfollow.docs.ligo.org/. [1] Ashton et al. ApJS 241, 27 (2019) doi:10.3847/1538-4365/ab06fc and Morisaki et al. PRD 108, 123040 (2023) doi:10.1103/PhysRevD.108.123040 View this GCN Circular online at https://gcn.nasa.gov/circulars/41080. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39132] GRB 250713A: JinShan optical upper limits
by GCN Circulars 13 Jul '25

13 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41079 SUBJECT: GRB 250713A: JinShan optical upper limits DATE: 25/07/13 19:06:10 GMT FROM: syfu(a)nao.cas.cn S.Y. Fu(HUST), S.Q. Jiang, J. An, X. Liu, Z.P. Zhu, L.B. He, D. Xu (NAOC), J.Z. Liu (XAO) report on behalf of a large collaboration: We observed the field of GRB250713A (sb25071320) detected by SVOM/ECLAIRs (Maggi et al., GCN 41078), using the 50cm & 100cm telescopes of the JinShan project, located at Altay, Xinjiang, China. Observations began at 17:08:08 UT on 2025-07-13, i.e., 102 seconds after the trigger, and a series of frames were obtained in the Sloan r, i and z-band. No new optical source is detected within the SVOM/MXT error circle, down to 5-sigma upper limits of r ~ 21.0, i ~ 17.7 and z ~ 20.8, calibrated with nearby Pan-STARRS stars and not corrected for Galactic extinction. We acknowledge the excellent support from T.Q. Chen for enabling these observations. View this GCN Circular online at https://gcn.nasa.gov/circulars/41079. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39131] GRB 250713A: SVOM detection of a short burst
by GCN Circulars 13 Jul '25

13 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41078 SUBJECT: GRB 250713A: SVOM detection of a short burst DATE: 25/07/13 17:46:03 GMT FROM: SVOM_group <svomgroup(a)bao.ac.cn> P. Maggi (ObAS), M. Brunet, L.Bouchet (IRAP), D. Gotz (CEA) report on behalf of the SVOM mission team: At 2025-07-13T17:06:26 UTC (T0), SVOM/ECLAIRs triggered and located the gamma-ray burst GRB 250713A (SVOM burst-id sb25071320). The following trigger information was received on the ground with low latency by the SVOM VHF Alert Network. The burst was detected both by the Count-Rate Trigger (CRT) and the Image Trigger (IMT), which produced a sequence of 7 alerts. IMT provided the alert with the best signal-to-noise-ratio in the image (SNR) of 14.04 in the [8-120] keV energy band over a time window of 40.96 seconds starting at 2025-07-13T17:06:02. The localization of the best alert is R.A., Dec. 336.9666, 38.7686 degrees (J2000) with a 90% confidence level (C.L.) radius of 5.84 arcmin (including systematic error of 2 arcmin added in quadrature). The lightcurve shows a short spike which could be followed by an extended emission. SVOM slewed to the burst. SVOM/MXT began observing the field at 2025-07-13T17:08:48 UTC, 142 seconds after T0. Using onboard processed data we found an uncatalogued X-ray source located at R.A., Dec. 336.9045, 38.7670 degrees: R.A. (J2000) = 22h27m37.09s Dec. (J2000) = 38d46m01.31s with a 90% C.L. radius of 55 arcseconds (including systematic error of 25 arcsec added in quadrature). This location is 2.90 arcminutes from the ECLAIRs onboard position. This position may be improved as more data is received. VT began observing the field after the slew. The analysis of the data will be published in a future circular. The Space-based multi-band astronomical Variable Objects Monitor (SVOM) is a China-France joint mission led by the Chinese National Space Administration (CNSA), French Space Agency (CNES), and the Chinese Academy of Sciences (CAS), which is dedicated to observing gamma-ray bursts and other transient phenomena in the energetic universe. SVOM/ECLAIRs was developed jointly by CNES, CEA-IRFU, CNRS-IRAP, CNRS-APC. SVOM/GRM was developed by the Institute of High Energy Physics (IHEP) of CAS. SVOM/MXT was developed jointly by CNES, CEA-IRFU, CNRS-IJCLab, University of Leicester, MPE. The Burst Advocate (BA) on shift for this alert is Pierre Maggi: pierre.maggi(a)astro.unistra.fr. Please contact the BA by email if you require additional information. View this GCN Circular online at https://gcn.nasa.gov/circulars/41078. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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