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

[vsnet-grb-info 38236] GRB 250419A: Mephisto Multi-band Optical Detection
by GCN Circulars 22 Apr '25

22 Apr '25

TITLE: GCN CIRCULAR NUMBER: 40210 SUBJECT: GRB 250419A: Mephisto Multi-band Optical Detection DATE: 25/04/22 17:40:55 GMT FROM: Chenxu Liu at Mephisto Team <cxliu(a)ynu.edu.cn> Edoardo Lagioia, Chenxu Liu, Yuan Fang, Guowang Du, Donglin Gao, Zhang Zepeng, Jinghua Zhang, Brajesh Kumar, Yuanpei Yang, Xiangkun Liu, Xiaowei Liu (all SWIFAR, YNU) report on behalf of the Mephisto Team: We conducted simultaneous multi-band photometric observations of the gamma-ray burst GRB 250419A (SVOM/ECLAIRs trigger sb25041901 at 2025-04-19T02:29:32 UTC; Wang et al. GCN 40168) with the Multi-channel Photometric Survey Telescope (Mephisto) of Yunnan University, located at the Lijiang Observatory. The observations extend over two nights from 19 to 20 April 2025. An optical counterpart is detected in the u-, g-, r-, i-band stacked images but not in the v-, z-band stack. The preliminary photometry and the 3σ upper limits are listed below. UT start |T-T0 (hr)| Band | Exp | Mag/LimMag (AB) -------------------|---------|------|--------|-------------------------- 2025/4/19 21:13:29 | 18.73 | u | 2x300s | > 20.63 2025/4/19 21:25:42 | 18.94 | v | 2x300s | > 20.91 2025/4/19 21:13:29 | 18.73 | g | 2x300s | 19.84 +/- 0.19 2025/4/19 21:25:42 | 18.94 | r | 2x300s | 19.92 +/- 0.10 2025/4/19 21:13:29 | 18.73 | i | 2x300s | 19.58 +/- 0.12 2025/4/19 21:25:42 | 18.94 | z | 2x300s | > 20.27 * Note: The above two sets of 300s exposures are taken at altitude ~ 23 deg. UT start |T-T0 (hr)| Band | Exp | Mag/LimMag (AB) -------------------|---------|------|--------|-------------------------- 2025/4/20 17:10:04 | 38.68 | u | 2x300s | 21.47 +/- 0.39 2025/4/20 17:10:06 | 38.68 | g | 2x300s | 21.00 +/- 0.17 2025/4/20 17:10:04 | 38.68 | i | 2x300s | 20.42 +/- 0.18 -------------------|---------|------|--------|-------------------------- 2025/4/20 19:50:05 | 41.34 | v | 1x300s | > 22.18 2025/4/20 19:50:04 | 41.34 | r | 1x300s | 21.15 +/- 0.29 2025/4/20 19:50:07 | 41.34 | z | 1x300s | > 21.30 Follow-up observations have already confirmed the presence of an optical counterpart ((López et al., GCN 40169; Xin et al., GCN 40170; Zheng et al., GCN 40171; Kumar et al., GCN 40172; Thakur et al., GCN 40174; Lipunov et al., GCN 40179; Odeh et al., GCN 40180; Perley & Bochenek, GCN 40181; Pankov et al., GCN 40182; Pérez-Fournon et al., GCN 40183; Kuin, GCN 40185; Wu et al., GCN 40186; Xie et al., GCN 40187; Jiang et al., GCN 40188; Ghosh et al., GCN 40189; Bochenek & Perley, GCN 40190; Pankov et al., GCN 40202; Gianluca Masi, GCN 40206; Giovanni Calapai & Massa S. Giorgio, GCN 40209). The ESO/X-Shooter spectroscopic observations identify a redshift of z = 0.845 (Thakur et al., GCN 40174). ---------------------------------------------------------- Mephisto (Multi-channel Photometric Survey Telescope) is a 1.6-m wide-field multi-channel telescope, the first of its type in the world, capable of imaging the same field of view in three optical bands simultaneously. It provides real-time, high-quality colors of stellar objects. The on-site telescope assemblage and commissioning were carried out in September 2022. The first light in all three channels was achieved on 2023 December 21. ---------------------------------------------------------- View this GCN Circular online at https://gcn.nasa.gov/circulars/40210. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38235] GRB 250419A: Calapai Observatory, Massa S. Giorgio (Messina), optical observations.
by GCN Circulars 22 Apr '25

22 Apr '25

TITLE: GCN CIRCULAR NUMBER: 40209 SUBJECT: GRB 250419A: Calapai Observatory, Massa S. Giorgio (Messina), optical observations. DATE: 25/04/22 15:45:12 GMT FROM: Giovanni Calapai at Calapai Astronomical Observatory, Massa S. Giorgio, Messina, Italy <giovannicalapai(a)tiscali.it> 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 observed the field of GRB 250419A detected by SVOM/ECLAIRs (Wang et al. GCN 40168) with the 11 inches Schmidt-Cassegrain (Celestron 11) telescope F/D=6,3. The observations were started at 2025-04-19 23:55 UT (approximately 21.43 hours after burst) stacking a set of unfiltered CCD image. The observations were carried out with clear skies and good visibility conditions. The OT was detected at the following position: RA (J2000.0) 13h 29m 37.33s Decl. (J2000.0) +07° 02' 27.5" Photometry was obtained using nearby PanSTARRS stars as follows: Observation Mid-Time T-T0 (hr) Exposure Filter Mag. Err. 2025-04-20 01:19:29 UT 22.83 164x60s CR 19.76 +/-0.06 Magnitude was calibrated with the nearby PanSTARRS stars converted using Lupton (2005) equations. No correction for galactic dust extinction was applied. Our observations are consistent with other already reported López et al. (GCN 40169), Xin et al. (GCN 40170), Zheng et al. (GCN 40171), Kumar et al. (GCN 40172), Lipunov et al. (GCN 40179), Odeh et al. (GCN 40180), Perley & Bochenek (GCN 40181), Pankov et al. (GCN 40182), Pérez-Fournon et al. (GCN 40183), Kuin (GCN 40185), Wu et al. (GCN 40186), Xie et al. (GCN 40187), Jiang et al. (GCN 40188), Ghosh et al. (GCN 40189), Bochenek & Perley (GCN 40190), Pankov et al. (GCN 40202), Masi (GCN 40206). The message may be cited. View this GCN Circular online at https://gcn.nasa.gov/circulars/40209. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38234] IC-250421A: LAST optical observations of the IceCube neutrino candidate
by GCN Circulars 22 Apr '25

22 Apr '25

TITLE: GCN CIRCULAR NUMBER: 40208 SUBJECT: IC-250421A: LAST optical observations of the IceCube neutrino candidate DATE: 25/04/22 13:56:21 GMT FROM: Simone Garrappa at Weizmann Institute of Science <simone.garrappa(a)weizmann.ac.il> S. Garrappa (WIS), R. Konno (WIS), E. A. Zimmerman (WIS), A. Horowicz (WIS), E. O. Ofek (WIS), S. Ben-Ami (WIS), D. Polishook (WIS), O. Yaron (WIS), S. Fainer (WIS), P. Chen (WIS), A. Krassilchtchikov (WIS), Y. M. Shani (WIS), E. Segre (WIS), A. Gal-Yam (WIS), S. Spitzer (WIS), and K. Rybicki (WIS) on behalf of the LAST Collaboration. We report the observations of the IceCube Bronze neutrino candidate IC-250421A with the Large Array Survey Telescope (LAST, Ofek et al. 2023; Ben-Ami et al. 2023). We observe the field of IC-250421A using four telescopes, each with a FoV of 7.4 deg^2 and no filter (clear - similar to the GAIA Bp band) over several epochs. In each epoch, we coadd 20x20s images. We observed for a total of 19 epochs under bright moon conditions, with an average limiting magnitude of 19.70 (AB). We find one candidate transient optical counterpart in our automatic transient-detection pipeline (Konno et al., in prep.). This is SN2025cbj, a known SN candidate classified as Type IIn (Sollerman et al., 2025) at redshift z = 0.07, which was discovered by ZTF on 20 02 2025 (~60 days before T0, https://alerce.online/object/ZTF25aagbrpb) SN2025cbj is located at ~1.8 deg distance from the IceCube best-fit localization, within the 90% localization error. We began observations on 21 04 2025 at 22:19:54 UTC (T-T0 = 5.23 hours). The observations cover part of the 90% neutrino footprint reported in GCN#40195 with predefined LAST observation fields. The following LAST field was observed: | Field| RA | Dec | Time | Limiting Mag (AB) | | ---- | ------ |-------- |----------- |------------ | | 1294 | 242.22 | 27 | 2459326.43 | 19.70 | Here we report the average brightness during the night: | RA (J2000)|Dec (J2000)| Mag (AB) | MagErr | Comment | | ---------- |-----------|-----------|--------|-------------| | 239.916993 | 27.111324 | 18.53 | 0.07 | SN 2025cbj | On 04 04 2025 (~17 days before T0) LAST observed the same field during nominal all-sky survey operations and detected SN2025cbj. We report the average source brightness from these archival observations. | RA (J2000)|Dec (J2000)| Mag (AB) | MagErr | Comment | | ---------- |-----------|-----------|--------|-------------| | 239.916993 | 27.111324 | 18.52 | 0.06 | SN 2025cbj | The reported magnitudes are in the AB system, calibrated using the LAST absolute photometric calibration pipeline (Garrappa et al. 2024). All reported errors are statistical only. The monitoring of this field will continue during LAST sky survey operations. We encourage multi-wavelength follow-up observations of this source. LAST is a survey telescope array of the Weizmann Astrophysical Observatory (https://www.weizmann.ac.il/wao/) View this GCN Circular online at https://gcn.nasa.gov/circulars/40208. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38233] EP250421a: NOT optical observations
by GCN Circulars 22 Apr '25

22 Apr '25

TITLE: GCN CIRCULAR NUMBER: 40207 SUBJECT: EP250421a: NOT optical observations DATE: 25/04/22 13:46:09 GMT FROM: Daniele B. Malesani at IMAPP / Radboud University <d.malesani(a)astro.ru.nl> D. B. Malesani (DAWN/NBI and Radboud), J. Sanchez-Sierras (Radboud), A. Martin-Carrillo (UCD), J. Quirola-Vásquez (Radboud), P. G. Jonker (Radboud), A. J. Levan (Radboud and Warwick), D. Xu (NAOC), Z. P. Zhu (NAOC), H. Dawson (IAP Potsdam), report on behalf of a larger collaboration: We observed the field of the fast X-ray transient EP250421a (Zhao et al., GCN 40198) using the Nordic Optical Telescope (NOT) equipped with the ALFOSC camera. Observations were carried out under poor seeing (1.8") in the r and z filters (3x300 s, each) starting on 2025-04-21 at 22:04:12 UT (5.79 hr after the trigger). At the location of the optical counterpart reported by Lee et al. (GCN 40192), Fu et al. (GCN 40193), and Liu et al. (GCN 40197), also consistent with the EP/FXT and Swift/XRT positions (Zhao et al., GCN 40198; Salvaggio et al., GCN 40204), we only marginally detect a source with r = 23.8 +/- 0.3 (AB), calibrated against nearby Pan-STARRS objects. View this GCN Circular online at https://gcn.nasa.gov/circulars/40207. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38232] GRB 250419A: Optical Observations via Virtual Telescope Project
by GCN Circulars 22 Apr '25

22 Apr '25

TITLE: GCN CIRCULAR NUMBER: 40206 SUBJECT: GRB 250419A: Optical Observations via Virtual Telescope Project DATE: 25/04/22 13:17:41 GMT FROM: Gianluca Masi at Virtual Telescope Project <gianluca(a)bellatrixobservatory.org> Gianluca Masi, Virtual Telescope Project (Italy), reports: We observed the field of GRB 250419A (Wang et al., GCN 40168) with the 14” robotic unit available at the Virtual Telescope Project facility in Manciano, Italy, equipped with a KAF-3200E based CCD camera. We collected 3, 300-second unfiltered exposures, then we averaged them. The central time of the resulting stack was 19 April, 21:07 UTC, that is about 18.6 hours after the burst. We clearly detect the optical counterpart of GRB 250419A. The position of the source is RA: 13 29 37.26; Decl.: +07 02 28.0 (J2000.0, mean residuals of 0.05”, reference stars from GaiaDR2) and the magnitude was estimated to be 19.3 (SNR=12, assuming R mags for the reference stars from GaiaDR2). The image is available here: https://www.virtualtelescope.eu/2025/04/22/grb-250419a-detection-of-the-opt… View this GCN Circular online at https://gcn.nasa.gov/circulars/40206. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38231] EP250421a: REM optical upper limit
by GCN Circulars 22 Apr '25

22 Apr '25

TITLE: GCN CIRCULAR NUMBER: 40205 SUBJECT: EP250421a: REM optical upper limit DATE: 25/04/22 09:22:46 GMT FROM: Riccardo Brivio at INAF-OAB <riccardo.brivio(a)inaf.it> R. Brivio, M. Ferro, D. Fugazza, P. D'Avanzo, S. Covino (INAF-OAB) report on behalf of the REM team: We observed the field of EP250421a (Zhao et al., GCN 40198) with the REM 60 cm robotic telescope located at the ESO observatory of La Silla (Chile). The observations were carried in the g, r, i, and z bands, started on 2025 April 21 at 23:08:27 UT (i.e. 6.9 hr after the burst), and lasted for about 1 hour. From preliminary inspection, we do not detect any counterpart at the position of the optical afterglow (Lee et al., GCN. 40192; Fu et al., GCN 40193; Liu et al., GCN 40197) down to the following 3sigma limit: r > 20.6 (AB; calibrated against the Pan-STARRS catalogue), at a mid-time of 7.4 hours after the trigger. View this GCN Circular online at https://gcn.nasa.gov/circulars/40205. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38230] EP250421a: Swift/XRT counterpart detection
by GCN Circulars 22 Apr '25

22 Apr '25

TITLE: GCN CIRCULAR NUMBER: 40204 SUBJECT: EP250421a: Swift/XRT counterpart detection DATE: 25/04/22 09:04:31 GMT FROM: Chiara Salvaggio at INAF OABrera <chiara.salvaggio(a)inaf.it> C. Salvaggio (INAF-OAB), T. Sbarrato (INAF-OAB), R. Brivio (INAF-OAB), M. Ferro (INAF-OAB), K. Page (U. Leicester), D. Malesani (DAWN/NBI and Radboud) and P.A. Evans (U. Leicester) report on behalf the Swift-XRT team: Swift/XRT has performed follow-up observations of EP-WXT detected transient EP250421a (trigger 01709135179, Zhao et al. GCN 40198). We searched for X-ray sources in 1.8 ks of Photon Counting (PC) mode data, from T0+5.8 ks to T0+11.7 ks after the EP-WXT trigger. We found an uncatalogued X-ray source within the estimated 3-sigma EP-WXT error region. Using 1772 s of XRT PC mode data and 2 UVOT images, we find an enhanced XRT position: RA, Dec = 172.420,-24.67568 which is equivalent to: RA (J2000): 11h 29m 40.80s Dec (J2000): -24° 40' 32.4" with an uncertainty of 2.7 arcsec (radius, 90% confidence). This position is 35 arcsec from the EP-WXT position, and consistent with the X-ray counterpart found in EP/FXT data (Zhao et al., GCN 40198) and with the optical counterpart reported by Lee et al. (GCN 40192), Fu et al. (GCN 40193), Liu et al. (GCN 40197). The source has a mean count rate of 0.272 ct/s and shows signs of fading at 2.8 sigma significance. The results of the XRT-team automatic analysis are available at https://www.swift.ac.uk/EP/EP_FIELD00035/ This circular is an official product of the Swift-XRT team. View this GCN Circular online at https://gcn.nasa.gov/circulars/40204. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38229] EP250421A: COLIBRÍ Optical Upper Limit
by GCN Circulars 22 Apr '25

22 Apr '25

TITLE: GCN CIRCULAR NUMBER: 40203 SUBJECT: EP250421A: COLIBRÍ Optical Upper Limit DATE: 25/04/22 08:13:37 GMT FROM: Rosa L. Becerra at Tor Vergata, Roma <rosa.becerra(a)roma2.infn.it> Rosa L. Becerra (U Roma), Camila Angulo (UNAM), Francis Fortin (IRAP), Alan M. Watson (UNAM), Stéphane Basa (UAR Pytheas), William H. Lee (UNAM), Jean-Luc Atteia (IRAP), Sarah Antier (OCA/IJCLAB), Dalya Akl (AUS), Nathaniel R. Butler (ASU), Damien Dornic (CPPM), Jean-Grégoire Ducoin (CPPM), 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), Antonio de Ugarte Postigo (LAM) and Benjamin Schneider (LAM) report: We imaged the field of EP250421A (Zhao et al., GCN Circ. 40198) with the DDRAGO wide-field imager on the COLIBRÍ telescope at the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir in Mexico on the night of 2025-04-22 UTC. We observed from 2025-04-22 04:54 to 06:03 UTC (T+12.6 to T+13.8 hours after the trigger) and obtained 50 minutes of exposure in total in the r filter. Our observations were performed under regular weather conditions. The data were coadded with the COLIBRÍ pipeline and analysed in STDWeb/STDPipe (Karpov 2025), with photometric calibration against Pan-STARRS DR1. Our photometry is in the AB system and is not corrected for Galactic extinction. At the position of the optical counterpart (Lee et al., GCN Circ. 40192; Fu et al., GCN Circ. 40193; Liu et al., GCN Circ. 40197), we obtained an upper limit (5-sgima) of: r > 23.44 We warmly thank the COLIBRÍ and DDRAGO engineering teams and the staff of the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir. View this GCN Circular online at https://gcn.nasa.gov/circulars/40203. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38228] GRB 250419A: Mondy Continued Optical Observations
by GCN Circulars 22 Apr '25

22 Apr '25

TITLE: GCN CIRCULAR NUMBER: 40202 SUBJECT: GRB 250419A: Mondy Continued Optical Observations DATE: 25/04/22 07:27:22 GMT FROM: Nicolai Pankov at HSE, IKI RAS <colinsergesen(a)gmail.com> N. Pankov (HSE, IKI), A. Pozanenko (IKI), E. Klunko (ISTP) report on behalf of IKI-GRB-FuN: We continued observations of the field of GRB 250419A (Wang et al., GCN 40168; Page et al., GCN 40111; Page et al., GCN 40176) at the redshift of z = 0.845 (Thakur et al., GCN 40174) with the 1.5-meter AZT-33IK telescope of the Sayan Solar Observatory (Mondy). The R-band observations began on 2025-04-20 at 15:54:03 UT, i.e. ~1.58 days since trigger. The optical counterpart (López et al., GCN 40169; Xin et al., GCN 40170; Zheng et al., GCN 40171; Kumar et al., GCN 40172; Thakur et al., GCN 40174; Lipunov et al., GCN 40179; Odeh et al., GCN 40180; Perley & Bochenek, GCN 40181; Pankov et al., GCN 40182; Pérez-Fournon et al., GCN 40183; Kuin, GCN 40185; Wu et al., GCN 40186; Xie et al., GCN 40187; Jiang et al., GCN 40188; Ghosh et al., GCN 40189; Bochenek & Perley, GCN 40190) is detected in the stacked image. The preliminary photometry is as follows: Date UTstart Exptime t-T0 Filter OT Err UL (s) (mid, days) (3sigma) 2025-04-20 15:54:03 45*120 1.58995 R 20.00 0.06 22.6 The photometry is based on nearby USNO-B1.0 stars (R2 magnitudes, provided in Pankov et al., GCN 40182) and has not been corrected for the Galactic extinction. View this GCN Circular online at https://gcn.nasa.gov/circulars/40202. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38227] Fermi GRB 250421A: Global MASTER-Net observations report
by GCN Circulars 22 Apr '25

22 Apr '25

TITLE: GCN CIRCULAR NUMBER: 40201 SUBJECT: Fermi GRB 250421A: Global MASTER-Net observations report DATE: 25/04/22 06:17:02 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov(a)xray.sai.msu.ru> V.Lipunov, E.Gorbovskoy, N.Tiurina, P.Balanutsa, , D.Vlasenko, I.Panchenko, A.Kuznetsov, G.Antipov, A.Sankovich, A.Sosnovskij, Yu.Tselik, M.Gulyaev, Ya.Kechin, V.Senik, A.Chasovnikov, K.Labsina, I. Gorbunov (Lomonosov MSU), O.Gress, N.Budnev (ISU), C.Francile, F. Podesta, R.Podesta, E. Gonzalez (Observatorio Astronomico Felix Aguilar (OAFA), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), A. Gabovich, V.Yurkov (Blagoveschensk Educational StateUniversity) D.Buckley (SAAO), R.Rebolo (The Instituto de Astrofisica de Canarias), L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory) MASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB 250421A ( Fermi GBM team, GCN 40191) errorbox 67295 sec after notice time and 67337 sec after trigger time at 2025-04-22 05:20:48 UT, with upper limit up to 18.9 mag. The observations began at zenith distance = 33 deg. The sun altitude is -68.2 deg. The galactic latitude b = -9 deg., longitude l = 328 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2848837 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 67368 | 2025-04-22 05:20:48 | MASTER-OAFA | (16h 29m 49.10s , -59d 22m 10.8s) | C | 60 | 18.4 | 67601 | 2025-04-22 05:24:42 | MASTER-OAFA | (16h 25m 54.95s , -61d 15m 16.6s) | C | 60 | 18.4 | 67790 | 2025-04-22 05:28:01 | MASTER-OAFA | (16h 37m 54.84s , -62d 00m 16.5s) | C | 40 | 17.4 | 67800 | 2025-04-22 05:28:01 | MASTER-OAFA | (16h 57m 07.49s , -61d 33m 46.3s) | C | 60 | 18.9 | 68001 | 2025-04-22 05:31:22 | MASTER-OAFA | (16h 29m 45.37s , -59d 21m 53.7s) | C | 60 | 18.3 | 68194 | 2025-04-22 05:34:44 | MASTER-OAFA | (16h 41m 10.93s , -60d 04m 07.5s) | C | 40 | 17.2 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited. View this GCN Circular online at https://gcn.nasa.gov/circulars/40201. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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