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

[vsnet-grb-info 38590] GRB 250527B / MAXI J1450-527 : MAXI/GSC detection
by GCN Circulars 27 May '25

27 May '25

TITLE: GCN CIRCULAR NUMBER: 40556 SUBJECT: GRB 250527B / MAXI J1450-527 : MAXI/GSC detection DATE: 25/05/27 22:44:00 GMT FROM: taiki.kawamuro(a)riken.jp T. Kawamuro (Osaka U.), M. Nakajima (Nihon U.), M. Serino (AGU), W. Iwakiri (Chiba U.), H. Negoro, K. Takagi, H. Takahashi, K. Tatano, H. Nishio (Nihon U.), T. Mihara, T. Tamagawa, N. Kawai, M. Matsuoka (RIKEN), T. Sakamoto, S. Sugita, Y. Kawakubo, H. Hiramatsu, Y. Kondo, A. Yoshida (AGU), Y. Tsuboi, H. Sugai, N. Nagashima (Chuo U.), M. Shidatsu, Y. Niida, C. Kang, T. Nakamoto (Ehime U.), I. Takahashi, M. Niwano, N. Higuchi, Y. Yatsu (Tokyo Tech), S. Nakahira, S. Ueno, H. Tomida, M. Ishikawa, S. Ogawa, M. Kurihara (JAXA), Y. Ueda, K. Fujiwara (Kyoto U.), M. Yamauchi, M. Nishio, C. Hiraizumi (Miyazaki U.), K. Yamaoka (Nagoya U.), M. Sugizaki (Kanazawa U.), S. Yamada (Tohoku U.) The MAXI/GSC nova alert system triggered a bright uncatalogued X-ray transient source at 2025-05-27 17:38:05 UT. Assuming that the source flux was constant over the transit, we obtain the source position at (R.A., Dec) = (222.622 deg, -52.704 deg) = (14 50 29, -52 42 14) (J2000) with a statistical 90% C.L. elliptical error region with long and short radii of 0.12 deg and 0.11 deg, respectively. The roll angle of long axis from the north direction is 90.0 deg counterclockwise. There is an additional systematic uncertainty of 0.1 deg (90% containment radius). The X-ray flux averaged over the scan was 350 +- 36 mCrab (4.0-10.0keV, 1 sigma error). Without assumptions on the source constancy, we obtain a rectangular error box for the transient source with the following corners: (222.154, -51.832) deg = (14 48 36, -51 49 55) (J2000) (221.831, -51.930) deg = (14 47 19, -51 55 48) (J2000) (222.883, -53.207) deg = (14 51 31, -53 12 25) (J2000) (223.212, -53.106) deg = (14 52 50, -53 06 21) (J2000) There was no significant excess flux in the previous transit at 17:17 UT and in the next transit at 18:50 UT with an upper limit of 20 mCrab for each. View this GCN Circular online at https://gcn.nasa.gov/circulars/40556. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38589] GCN Announcement: Browse Circulars by Event, Advanced Search, Sample Codes, Schema Release
by GCN Announcements 27 May '25

27 May '25

The GCN Team is pleased to announce new features, documentation, and a schema release on https://gcn.nasa.gov. Browse Circulars by Event By popular demand, you can now view Circulars grouped by astronomical event. In the Circulars archive (https://gcn.nasa.gov/circulars) you can now toggle between two view modes: Circulars View - View Circulars sorted inversely by Circular ID. - Use the search bar to search for text strings (e.g. https://gcn.nasa.gov/circulars/?view=index&query=250101A&startDate=&endDate=) Circulars numbers (e.g. 12345; https://gcn.nasa.gov/circulars?view=index&query=12345) or use Advanced Search (see below). Events View - View a list of astronomical events (e.g. GRB 250101A; https://gcn.nasa.gov/circulars?view=group&query=GRB+250101A) LIGO/Virgo/KAGRA S250331o (https://gcn.nasa.gov/circulars?view=group&query=LIGO%2FVirgo%2FKAGRA+S25033…) EP250101a (https://gcn.nasa.gov/circulars?view=group&query=EP250101a) expand to show all Circulars associated with that event, or tap the event name to see all related Circulars in sequence (similar to the GCN Classic Circulars archive). - Use the search bar to search by event name (e.g. GRB 250404A). - The GCN Team manually associates events with multiple names (e.g. GRB 250404A, EP250404a; https://gcn.nasa.gov/circulars/events/grb-250404a) into event groups. You can view all Circulars associated with any member of an event group by selecting that event in the event view. You can also search for an event by any event name that group. If you would like to suggest additional event names that should be in the same event group, please contact the GCN Team (https://gcn.nasa.gov/support) See additional documentation (https://gcn.nasa.gov/docs/circulars/archive) on event view, event names, and event groups. Circulars Advanced Search The Circulars archive (https://gcn.nasa.gov/circulars) now allows users to search for keywords by Subject, Body, and Submitter. Select "Advanced Search" to view and copy example syntax. See documentation (https://gcn.nasa.gov/docs/circulars/archive#advanced-search) for more details, examples, and compound query logic. Mission Notices Table The Missions page (https://gcn.nasa.gov/missions) now contains a table listing the status of all current, past, and upcoming Notices producers. You can learn about the formats and distribution mechanisms that are available for every Notice type, including the transitions to GCN Kafka. The table provides mission-specific links to signup for Notices over email and the Kafka start streaming guide. Notices Sample Code Sample code (https://gcn.nasa.gov/docs/sample) serves as a starting point for consumers of GCN Notices for functions including consuming Kafka messages, parsing plain text, VOEvent XML, and JSON format notices, and interacting with HEALPix maps. We have also included producer sample code for encoding embedded data (e.g. HEALPix maps). The GCN Team welcomes contributions of additional sample code that might be of use to our community. Apache Spark Kafka client We added Kafka client sample code for Apache Spark (https://gcn.nasa.gov/docs/client#pyspark) Apache Spark (https://spark.apache.org) is a multi-language engine for executing data engineering, data science, and machine learning on single-node machines or clusters. Schema v4.4.1 GCN Schema v4.4.1 is available with recent changes including the generic high-energy neutrino and fast radio burst schema (Release Notes; https://github.com/nasa-gcn/gcn-schema/releases/tag/v4.4.1) For more details on this new feature and an archive of GCN news and announcements, see https://gcn.nasa.gov/news. For questions, issues, or bug reports, please contact us via: - Contact form: https://gcn.nasa.gov/contact - GitHub issue tracker: https://github.com/nasa-gcn/gcn.nasa.gov/issues --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38588] GRB 250527A: Fermi GBM Final Localization
by GCN Circulars 27 May '25

27 May '25

TITLE: GCN CIRCULAR NUMBER: 40555 SUBJECT: GRB 250527A: Fermi GBM Final Localization DATE: 25/05/27 19:44:11 GMT FROM: eliza.neights(a)gmail.com The Fermi GBM team reports the detection of a likely LONG GRB "At 17:06:07.26 UT on 27 May 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250527A (trigger 770058372/250527713). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 30.5, Dec = 15.0 (J2000 degrees, equivalent to J2000 2h 2m, 15d 2'), with a statistical uncertainty of 9.7 degrees. The angle from the Fermi LAT boresight is 58.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250527713/… The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250527713/… The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250527713/…" View this GCN Circular online at https://gcn.nasa.gov/circulars/40555. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38587] EP250526a: refined analysis of the EP-WXT and EP-FXT observations
by GCN Circulars 27 May '25

27 May '25

TITLE: GCN CIRCULAR NUMBER: 40554 SUBJECT: EP250526a: refined analysis of the EP-WXT and EP-FXT observations DATE: 25/05/27 12:44:31 GMT FROM: EP Team at NAOC/CAS <ep_ta(a)bao.ac.cn> Jiahua Wu (GZHU), D. Y. Li (NAO, CAS), B.-T. Wang (YNAO, CAS), W. F. Wen (SZTU) and Y. Liu (NAO, CAS) report on behalf of the Einstein Probe team: The X-ray transient EP250526a was detected by the Wide-field X-ray Telescope (WXT) on board the Einstein Probe (EP) mission (Li et al., GCN 40550), and followed up by several optical telescopes (Lipunov et al, GCN 40551, Angulo et al., GCN 40552), while no optical counterpart has been detected yet. Refined analysis of the WXT data shows that the event started at T0=2025-05-26T19:24:55 (UTC) and lasted for about 175 s (T90). The peak flux (0.5-4 keV) is estimated to be 4 x 10^-9 erg/s/cm^2 (T0+39 s). The averaged 0.5-4 keV spectrum of T90 can be fitted with an absorbed power-law with a Galactic hydrogen column density of 7 x 10^20 cm^-2 and a photon index of 1.31 (-/+0.42). The derived average unabsorbed 0.5-4 keV flux is 1.75 (-0.37, +0.51) x 10^-9 erg/s/cm^2. The Follow-up X-ray Telescope (FXT) on board EP observed this source autonomously at 2025-05-26T19:31:10, about 375 seconds after T0, with an exposure time of 2270 seconds. The averaged 0.5-10 keV spectrum can be fitted with an absorbed power-law with a photon index of 2.59 (-0.43, +0.44). The derived unabsorbed 0.5-10 keV flux is 7.0 (-1.4, +2.0) x 10^-13 erg/s/cm^2. Another FXT observation was conducted at 2025-05-27T04:18:56, about 9 hours after T0. The X-ray spectrum can be fitted with an absorbed power-law with a photon index of 2.37 (-0.93, +0.91), and the derived unabsorbed 0.5-10 keV flux is 1.2 (-0.5, +1.2) x 10^-13 erg/s/cm^2. The absorption was fixed at the Galactic value during the spectral fitting. The uncertainties are at the 90% confidence level for the above parameters. 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). The contact TA of this source is Jiahua Wu, please contact him via the email jhwu(a)e.gzhu.edu.cn if needed. View this GCN Circular online at https://gcn.nasa.gov/circulars/40554. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38586] GRB 250314A: CIDER NB1008 upper limit
by GCN Circulars 27 May '25

27 May '25

TITLE: GCN CIRCULAR NUMBER: 40553 SUBJECT: GRB 250314A: CIDER NB1008 upper limit DATE: 25/05/27 12:41:08 GMT FROM: Zhen-Ya Zheng at Shanghai Astronomical Observatory, CAS <zhengzy(a)shao.ac.cn> Z.-Y. Zheng (SHAO), S.R. Zhu (SHAO), J. X. Wang (USTC), J. E. Rhoads (NASA/GSFC), S. Malhotra (NASA/GSFC), I. G. B. Wold (NASA/GSFC), F. Barrientos (PUC), L. Infante (LCO), W. Hu (TAMU), C. Jiang (SHAO), D. Xu (NAOC), and F. Valdes (NOIRLab) report on behalf of the CIDER collaboration: We observed the near-infrared NB1008 narrowband counterpart (Malesani et al., GCN 39727; see also Kennea et al., GCN 39734; Turpin et al., GCN 39739) of the SVOM/ECLAIRs GRB 250314A (Wang et al., GCN 39719), using the Blanco 4m Telescope equipped with the Dark Energy Camera and a small fraction of the CIDER project’s observing time. A sequence of 19 exposures of 540 s each and 4 exposures of 180s each (3.1 hrs in total) was secured in the NB1008 band, with mid time 2025 April 3 (on Apr. 2-4, about 20 days after the GRB). In a preliminary reduction, no source is detected at the GRB position down to a 1-sigma upper limiting magnitude NB1008 ~ 23.5 (AB), calibrated with the communication pipeline for DES. We also took a 0.35 hrs exposure in the i-band with DECam and no source is detected down to a 1-sigma upper limiting magnitude of i ~ 26.7 (AB), consistent with the high redshift of this GRB. If the redshift 7.27 is correct from the previous spectroscopic and photometric confirmation (z ~ 7.27; Malesani et al., GCN 39732; Rakotondrainibe et al., GCN 39743), the NB1008 filter would cover the pure Lya flux of the GRB host galaxy. The NB1008 band‘s 1-sigma upper limit of 23.5 (AB) can be converted to a Lya flux of < 4.2e-17 erg/cm^2/s, and a Lya luminosity of < 3.1e+43 erg/s at z=7.27. Based on the line emission ratio of Lya to Ha in Case B recombination (Osterbrock et al. 1989) and the relation between SFR and the Ha luminosity (Kennicutt 1998), the derived SFR of the GRB host galaxy is < 28 M_sun/yr (1-sigma upper limit). View this GCN Circular online at https://gcn.nasa.gov/circulars/40553. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38585] EP250526a: COLIBRÍ optical upper limits
by GCN Circulars 27 May '25

27 May '25

TITLE: GCN CIRCULAR NUMBER: 40552 SUBJECT: EP250526a: COLIBRÍ optical upper limits DATE: 25/05/27 08:15:01 GMT FROM: Benjamin Schneider at MIT <bschn(a)mit.edu> Camila Angulo (UNAM), Benjamin Schneider (LAM), Rosa L. Becerra (U Roma), Stéphane Basa (UAR Pytheas), William H. Lee (UNAM), Alan M. Watson (UNAM), Fredd Alvarez (UNAM), Jean-Luc Atteia (IRAP), 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) and Antonio de Ugarte Postigo (LAM): We imaged the field of the EP250526a (Li et al., GCN Circ. 40550) using the DDRAGO wide-field imager on the COLIBRÍ telescope. We observed from 2025-05-27 03:30 to 5:35 UTC (from 8.0 to 10.1 hours after the trigger and 58 minutes after the notice) and obtained 32 minutes of exposure in g, r and i filters (each one). 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 SkyMapper catalog, is in the AB system, and is not corrected for Galactic extinction. In the stacked images, we do not detect any new source at the FXT position (Li et al., GCN Circ. 40550) down to the following 3-sigma limit: g > 23.6 r > 23.4 i > 23.0 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/40552. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38584] EP250526a: COLIBRÍ optical upper limits
by GCN Circulars 27 May '25

27 May '25

TITLE: GCN CIRCULAR NUMBER: 40552 SUBJECT: EP250526a: COLIBRÍ optical upper limits DATE: 25/05/27 08:15:01 GMT FROM: Benjamin Schneider at MIT <bschn(a)mit.edu> Camila Angulo (UNAM), Benjamin Schneider (LAM), Rosa L. Becerra (U Roma), Stéphane Basa (UAR Pytheas), William H. Lee (UNAM), Alan M. Watson (UNAM), Fredd Alvarez (UNAM), Jean-Luc Atteia (IRAP), 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) and Antonio de Ugarte Postigo (LAM): We imaged the field of the EP250526a (Li et al., GCN Circ. 40550) using the DDRAGO wide-field imager on the COLIBRÍ telescope. We observed from 2025-05-27 03:30 to 5:35 UTC (from 8.0 to 10.1 hours after the trigger and 58 minutes after the notice) and obtained 32 minutes of exposure in g, r and i filters (each one). 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 SkyMapper catalog, is in the AB system, and is not corrected for Galactic extinction. In the stacked images, we do not detect any new source at the FXT position (Li et al., GCN Circ. 40550) down to the following 3-sigma limit: g > 23.6 r > 23.4 i > 23.0 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/40552. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38583] EP250526a: Global MASTER-Net observations report
by GCN Circulars 27 May '25

27 May '25

TITLE: GCN CIRCULAR NUMBER: 40551 SUBJECT: EP250526a: Global MASTER-Net observations report DATE: 25/05/27 07:36:46 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov(a)xray.sai.msu.ru> V.Lipunov, E.Gorbovskoy, A.Kuznetsov, K.Zhirkov, I.Panchenko, N.Tiurina, P.Balanutsa, V.Topolev, D.Vlasenko, G.Antipov, A.Sankovich, Yu.Tselik, 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.Sosnovskij (CrAO), 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) was pointed to the EP250526a ( EP Team et al., GCN 40550) errorbox 15422 sec after notice time and 42778 sec after trigger time at 2025-05-27 07:21:21 UT, with upper limit up to 18.6 mag. The observations began at zenith distance = 57 deg. The sun altitude is -51.0 deg. The galactic latitude b = 24 deg., longitude l = 325 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2883070 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 42809 | 2025-05-27 07:21:21 | MASTER-OAFA | (14h 28m 05.95s , -34d 00m 45.3s) | C | 60 | 18.6 | 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/40551. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38582] EP250526a: Einstein Probe detection of a fast X-ray transient
by GCN Circulars 27 May '25

27 May '25

TITLE: GCN CIRCULAR NUMBER: 40550 SUBJECT: EP250526a: Einstein Probe detection of a fast X-ray transient DATE: 25/05/27 03:02:34 GMT FROM: EP Team at NAOC/CAS <ep_ta(a)bao.ac.cn> D. Y. Li (NAO, CAS), B.-T. Wang (YNAO, CAS), W. F. Wen (SZTU), J. H. Wu (GZHU), Y. Liu (NAO, CAS) on behalf of the Einstein Probe (EP) team: We report on the detection of a fast X-ray transient by the Wide-field X-ray Telescope (WXT) on board the Einstein Probe (EP) mission, designated EP250526a. The transient triggered EP-WXT (ID: 01709176979) at 2025-05-26 19:28:23 (UTC). The WXT position of the source is R.A. = 217.049 deg, DEC = -34.355 deg (J2000) with an uncertainty of 2.9 arcmin in radius (90% C.L. statistical and systematic). A follow-up observation with the Follow-up X-ray Telescope (FXT) was performed automatically. Within the WXT error circle, an uncatalogued X-ray source was detected at R.A. = 217.0509 deg, DEC = -34.3293 deg (J2000) with an uncertainty of 10 arcsec in radius (90% C.L. statistical and systematic). Further information will be updated when the telemetry data is received. 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/40550. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38581] EP J1350.0-8622: BOOTES-6/DPRT optical upper limit
by GCN Circulars 26 May '25

26 May '25

TITLE: GCN CIRCULAR NUMBER: 40549 SUBJECT: EP J1350.0-8622: BOOTES-6/DPRT optical upper limit DATE: 25/05/26 21:51:45 GMT FROM: I. Perez-Garcia at Institute of Astrophysics of Andalusia <ipg(a)iaa.es> I. Perez-Garcia, E. Fernandez-Garcia, M.D. Caballero-Garcia, R. Sanchez-Ramirez, S. Guziy, S.-Y. Wu, G. Garcia-Segura and A. J. Castro-Tirado (IAA-CSIC, Granada), P. J. Meintjes and H. J. van Heerden (UFS, South Africa), A. Martin-Carrillo and L. Hanlon (UCD, Ireland), M. Gritsevich (Univ. of Helsinki) and C. J. Perez del Pulgar (UMA, Malaga), on behalf of a larger collaboration, report: Following the detection of X-ray transient candidate EP J1350.0-8622 by Einstein Probe (Liu et al., GCNC [40548](https://gcn.nasa.gov/circulars/40548)) the BOOTES-6/DPRT 0.6m robotic telescope at Boyden Observatory in Maselspoort (South Africa) responded to this event starting on May 26, 16:59 UT (~ 17.7 h after trigger). No new source is detected in the WXT region up to magnitude 20.3 using the clear filter and Gaia DR3 Gmag magnitude as reference. We thank the staff at Boyden Observatory for their excellent support. View this GCN Circular online at https://gcn.nasa.gov/circulars/40549. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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