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

[vsnet-grb-info 37276] GRB 250210A: AstroSat CZTI detection
by GCN Circulars 10 Feb '25

10 Feb '25

TITLE: GCN CIRCULAR NUMBER: 39267 SUBJECT: GRB 250210A: AstroSat CZTI detection DATE: 25/02/10 10:39:26 GMT FROM: Gaurav Waratkar at IIT Bombay <gauravwaratkar(a)iitb.ac.in> A. Dasgupta (BITS Pilani, Hyderabad), G. Waratkar (IITB), J. Joshi (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 250210A which was also detected by Fermi/GBM (Fermi-GBM Team, GCN Circ. 39262). Inspection of INTEGRAL/SPI-ACS data also showed the detection of the burst. The source was clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2025-02-10 05:31:58.0 UTC. The measured peak count rate is 293 (+69, -41) counts/s above the background in the combined Veto data of all quadrants, with a total of 4599 (+645, -696) counts. The local mean background count rate was 1317 (+7, -7) counts/s. We measure a T90 of 29 (+2, -2) s from the cumulative Veto light curve. The source was also faintly detected in the CZT detectors in the 20-200 keV energy range. 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 View this GCN Circular online at https://gcn.nasa.gov/circulars/39267. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 37275] EP250207b: a new X-ray transient detected by Einstein Probe
by GCN Circulars 10 Feb '25

10 Feb '25

TITLE: GCN CIRCULAR NUMBER: 39266 SUBJECT: EP250207b: a new X-ray transient detected by Einstein Probe DATE: 25/02/10 09:16:09 GMT FROM: EP Team at NAOC/CAS <ep_ta(a)bao.ac.cn> X.-Y. Zhou (PRIC), A. Li (BNU), D.-H. Zhao, X.-P. Xu, Q.-Y. Wu and Y. Liu (NAOC, CAS) report on behalf of the Einstein Probe team: We report on the detection of an X-ray transient, designated EP250207b, by the Wide-field X-ray Telescope (WXT) on board the Einstein Probe (EP) mission. The transient event started at T0=2025-02-07T21:47:56(UTC) and lasted for more than 120 s before the observation ended. The WXT position of the source is R.A. = 167.495 deg, DEC = -7.906 deg (J2000) with an uncertainty of 2.7 arcmin in radius (90% C.L. statistical and systematic). The average WXT 0.5-4 keV spectrum can be fitted with an absorbed power law with a fixed Galactic equivalent hydrogen column density of 4.24 x 10^20 cm^-2 and a photon index of 0.6 (-0.8/+0.8). The derived average unabsorbed 0.5-4 keV flux is 6.1 (-2.5/+4.2) x 10^(-10) erg/s/cm^2. Two ToO observations were performed by the Follow-up X-ray Telescope (FXT) . The first observation started at 2025-02-08T14:52:06 (~T0+17h) with an exposure time of 3024 s. An uncatalogued source was detected at R.A. = 167.5130, DEC = -7.8695 (J2000) with an uncertainty of 10 arcsec (radius, 90% C.L. statistical and systematic). The average FXT 0.5-10 keV spectrum can be fitted with an absorbed power law with a fixed Galactic equivalent hydrogen column density of 4.24 x 10^20 cm^-2 and a photon index of 1.5 (-0.6/+0.6), giving an average unabsorbed 0.5-10 keV flux of 3.6 (-1.4/+3.5) x 10^(-13) erg/s/cm^2. The second observation started at 2025-02-09T18:10:59 (~T0+44h) with an exposure time of 5042 s. The uncatalogued source was detetcted with a declined flux of 6.4 (-2.8/+3.5) x 10^(-14) erg/s/cm^2, indicating its correlation with EP250207b. The uncertainties are at the 90% confidence level for the above parameters. Further follow-up observations are encouraged to identify the nature of this X-ray transient. 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/39266. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 37274] LIGO/Virgo/KAGRA S250206dm: MASTER detection AT2025bbo
by GCN Circulars 10 Feb '25

10 Feb '25

TITLE: GCN CIRCULAR NUMBER: 39265 SUBJECT: LIGO/Virgo/KAGRA S250206dm: MASTER detection AT2025bbo DATE: 25/02/10 09:10:56 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov(a)xray.sai.msu.ru> V.Lipunov, E.Gorbovskoy, A.Kuznetsov, N.Tiurina, D.Vlasenko, P.Balanutsa, I.Panchenko, A.Chasovnikov K.Zhirkov, G.Antipov, A.Sankovich, I.Gorbunov, A.Sosnovskij, Yu.Tselik, Ya.Kechin, V.Senik, V.Topolev (Lomonosov MSU), O.Gress, N.Budnev, O.Ershova (ISU), C.Francile, F. Podesta, R.Podesta, E. Gonzalez (Observatorio Astronomico Felix Aguilar (OAFA), D.Buckley (SAAO), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), A. Gabovich, V.Yurkov (Blagoveschensk Educational StateUniversity), 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) Global MASTER robotic net (Applied Physics Institute, ISU, Lipunov, Korniov, Gorbovskoy, Tiurina & Kuznetsov, 2023, Astronomical Robotic Networks and Operative Multichanel Astrophysics, Lomonosov MSU PRESS, 591 pp. https://msupress.com/en/catalogue/books/book/astronomicheskie-robotizirovan…) detected OT AT2025bbo (Smart et al., GCN 39244) in GW LVK error area S250206dm (The LIGO-Virgo-Kagra Collaboration, GCN 39175) with 19.1 unfiltered magnitude at 2025-02-09 16:54:16 (exp = 1440 sec).. The deep image is welcome. View this GCN Circular online at https://gcn.nasa.gov/circulars/39265. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 37273] GRB 250209A: MAXI/GSC detection (possible detection of an X-ray flare from 1RXS J145110.3+310648)
by GCN Circulars 10 Feb '25

10 Feb '25

TITLE: GCN CIRCULAR NUMBER: 39264 SUBJECT: GRB 250209A: MAXI/GSC detection (possible detection of an X-ray flare from 1RXS J145110.3+310648) DATE: 25/02/10 06:51:48 GMT FROM: Hitoshi Negoro at Nihon University/MAXI team <negoro.hitoshi(a)nihon-u.ac.jp> H. Negoro, H. Nishio (Nihon U.), T. Mihara (RIKEN), M. Serino (AGU), M. Nakajima, Y. Kudo, H. Shibui, K. Takagi, H. Takahashi, K. Tatano (Nihon U.), S. Yamada, T. Tamagawa, N. Kawai, M. Matsuoka (RIKEN), T. Sakamoto, S. Sugita, Y. Kawakubo, H. Hiramatsu, H. Nishikawa, Y. Kondo, S. Sasao, A. Yoshida (AGU), Y. Tsuboi, H. Sugai, N. Nagashima (Chuo U.), M. Shidatsu, Y. Niida (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, Y. Okada, K. Fujiwara (Kyoto U.), M. Yamauchi, Y. Otsuki, T. Hasegawa, M. Nishio (Miyazaki U.), K. Yamaoka (Nagoya U.), M. Sugizaki (Kanazawa U.), W. Iwakiri (Chiba U.), T. Kawamuro (Osaka U.), report on behalf of the MAXI team: The MAXI/GSC detected a relatively soft X-ray transient source at 11:00 UT on February 9, 2025. Assuming that the source flux was constant over the transit, we obtain the source position at (R.A., Dec) = (222.844 deg, 30.986 deg) = (14 51 22, +30 59 09) (J2000) with a statistical 90% C.L. elliptical error region with long and short radii of 0.35 deg and 0.32 deg, respectively. The roll angle of the long axis from the north direction is 54.0 deg counterclockwise. There is an additional systematic uncertainty of 0.1 deg (90% containment radius). The X-ray flux averaged over the scan was 133 +- 34 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: (R.A., Dec) = (221.544, 29.670) deg = (14 46 10, +29 40 12) (J2000) (R.A., Dec) = (222.164, 29.349) deg = (14 48 39, +29 20 56) (J2000) (R.A., Dec) = (223.910, 31.810) deg = (14 55 38, +31 48 35) (J2000) (R.A., Dec) = (223.280, 32.140) deg = (14 53 07, +32 08 24) (J2000) There was no significant excess flux in the previous transit at 09:27 UT and in the next transit at 12:33 UT with an upper limit of 20 mCrab for each. This transient event is positionally consistent with a nearby M4.0Ve star G 166-49 (a.k.a. 1RXS J145110.3+310648) and GRB 190306A (GCN Circ. 23937, 23941). This and the relatively soft X-ray spectrum suggest that this event originates from an X-ray flare from G 166-49. If so, the luminosity of the flare is about 6.0e31 erg/cm2/s for 13 pc distance, and that GRB 190306A might be an X-ray flare from this source though GRB 190306A showed a harder spectrum. We also designates this event GRB 250209A because of the un-identification. We crosspost this to the ATel and the GCN Circular for both communities. View this GCN Circular online at https://gcn.nasa.gov/circulars/39264. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 37272] Fermi GRB 250210A: Global MASTER-Net observations report
by GCN Circulars 10 Feb '25

10 Feb '25

TITLE: GCN CIRCULAR NUMBER: 39263 SUBJECT: Fermi GRB 250210A: Global MASTER-Net observations report DATE: 25/02/10 05:46:02 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 250210A ( Fermi GBM team, GCN 39262) errorbox 87 sec after notice time and 123 sec after trigger time at 2025-02-10 05:33:43 UT, with upper limit up to 19.3 mag. The observations began at zenith distance = 6 deg. The sun altitude is -43.4 deg. The galactic latitude b = 23 deg., longitude l = 262 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2774098 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 133 | 2025-02-10 05:33:43 | MASTER-OAFA | (09h 54m 55.98s , -29d 23m 26.3s) | C | 20 | 17.7 | 133 | 2025-02-10 05:33:43 | MASTER-OAFA | (10h 05m 22.08s , -28d 58m 37.7s) | C | 20 | 19.2 | 175 | 2025-02-10 05:34:29 | MASTER-OAFA | (10h 00m 11.61s , -27d 39m 32.1s) | C | 10 | 17.1 | 185 | 2025-02-10 05:34:30 | MASTER-OAFA | (10h 10m 27.82s , -27d 14m 47.7s) | C | 30 | 19.3 | 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/39263. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 37271] GRB 250210A: Fermi GBM Final Real-time Localization
by GCN Circulars 10 Feb '25

10 Feb '25

TITLE: GCN CIRCULAR NUMBER: 39262 SUBJECT: GRB 250210A: Fermi GBM Final Real-time Localization DATE: 25/02/10 05:42:14 GMT FROM: Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply(a)GIOC.nsstc.nasa.gov> The Fermi GBM team reports the detection of a likely LONG GRB At 05:31:40 UT on 10 Feb 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250210A (trigger 760858305.125996 / 250210230). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 150.3, Dec = -25.5 (J2000 degrees, equivalent to J2000 10h 01m, -25d 30'), with a statistical uncertainty of 2.8 degrees. The angle from the Fermi LAT boresight is 30.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250210230/… The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250210230/… The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250210230/… View this GCN Circular online at https://gcn.nasa.gov/circulars/39262. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 37270] LIGO/Virgo/KAGRA S250206dm: Upper limits from GECAM Observations
by GCN Circulars 10 Feb '25

10 Feb '25

TITLE: GCN CIRCULAR NUMBER: 39261 SUBJECT: LIGO/Virgo/KAGRA S250206dm: Upper limits from GECAM Observations DATE: 25/02/10 03:19:49 GMT FROM: yqzhang_cl(a)163.com Ce Cai (HEBNU), Shao-Lin Xiong, Yan-Qiu Zhang, Wen-Jun Tan, Chen-Wei Wang, Yue Wang and Jin-Peng Zhang (IHEP) report on behalf of the GECAM team: At the event time 2025-02-06T21:25:30.439 (UTC) of S250206dm (GCN 39175; GCN 39178; GCN 39231), GECAM-C was observing normally and monitored 66.9% of the localization probability region of this GW event, while GECAM-A and GECAM-B detectors were turned off. There was no GECAM-C in-flight trigger around the event time of S250206dm. The routine blind search of GECAM-C data also found no burst candidate. Thus, we implemented a targeted search [1] within +/-30 s around the event time, and identified no candidate above 3 sigma. Considering three typical GRB spectral models (i.e. soft, normal and hard Band functions), three timescales and the center region of GW localization (RA= 38.21°, Dec = 53.47°), the 3 sigma upper limits of the GRB energy flux (10 keV-1000 keV, in units of 10^-7 erg/s/cm^2) are reported below: Timescale (s) Soft Normal Hard 0.1 1.84 2.33 4.10 1 0.58 0.73 1.29 10 0.18 0.23 0.41 With the median luminosity distance of 373 Mpc from the GW detection (GCN 39231), we further calculate the following upper limits of the GRB intrinsic luminosity (1 keV-10 MeV, in units of 10^49 erg/s): Timescale (s) Soft Normal Hard 0.1 0.46 0.55 3.39 1 0.14 0.17 1.06 10 0.05 0.05 0.33 We note that all these results are preliminary and refined analysis will be reported. Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor (GECAM) mission originally consists of two micro-satellites (GECAM-A and GECAM-B) launched in Dec. 2020. As the third member of GECAM constellation, GECAM-C was launched onboard SATech-01 experimental satellite in July 2022. GECAM mission is funded by the Chinese Academy of Sciences (CAS). [1] C. Cai et al. MNRAS 508, 3910–3920 (2021) https://doi.org/10.1093/mnras/stab2760 View this GCN Circular online at https://gcn.nasa.gov/circulars/39261. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 37269] IceCube-250207A: Upper limits from a search for additional neutrino events in IceCube
by GCN Circulars 09 Feb '25

09 Feb '25

TITLE: GCN CIRCULAR NUMBER: 39260 SUBJECT: IceCube-250207A: Upper limits from a search for additional neutrino events in IceCube DATE: 25/02/09 22:02:46 GMT FROM: Alicia Mand at IceCube/UW-Madison <aemand(a)wisc.edu> The IceCube Collaboration (http://icecube.wisc.edu/) reports: IceCube has performed a search [1] for additional track-like muon neutrino events arriving from the direction of IceCube-250207A (https://gcn.nasa.gov/circulars/39203) in a time range of 1000 seconds centered on the alert event time (2025-02-07 01:59:35.270 UTC to 2025-02-07 02:16:15.270 UTC) during which IceCube was collecting good quality data. Excluding the event that prompted the alert, zero track-like events are found within the 90% containment region of IceCube-250207A. The IceCube sensitivity to neutrino point sources with an E^-2.5 spectrum (E^2 dN/dE at 1 TeV) within the locations spanned by the 90% spatial containment region of IceCube-250207A is 1.4e-01 GeV cm^-2 in a 1000 second time window. 90% of events IceCube would detect from a source at this declination with an E^-2.5 spectrum have energies in the approximate energy range between 2e+02 GeV and 9e+04 GeV. A subsequent search was performed including 2 days of data centered on the alert event time (2025-02-06 02:07:55.270 UTC to 2025-02-08 02:07:55.270 UTC). In this case, we report a p-value of 0.20, consistent with no significant excess of track events. The IceCube sensitivity to neutrino point sources with an E^-2.5 spectrum (E^2 dN/dE at 1 TeV) within the locations spanned by the 90% spatial containment region of IceCube-250207A is 1.7e-01 GeV cm^-2 in a 2 day time window. The IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc(a)icecube.wisc.edu. [1] IceCube Collaboration, R. Abbasi et al., ApJ 910 4 (2021) View this GCN Circular online at https://gcn.nasa.gov/circulars/39260. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 37268] LIGO/Virgo/KAGRA S250206dm: COLIBRÍ/DDRAGO Observations of AT2025bbo and Galaxies in the Localization Volume
by GCN Circulars 09 Feb '25

09 Feb '25

TITLE: GCN CIRCULAR NUMBER: 39258 SUBJECT: LIGO/Virgo/KAGRA S250206dm: COLIBRÍ/DDRAGO Observations of AT2025bbo and Galaxies in the Localization Volume DATE: 25/02/09 20:50:19 GMT FROM: Alan Watson at UNAM <alan(a)astro.unam.mx> Jean-Grégoire Ducoin (CPPM), Rosa L. Becerra (U Rome), Dalya Akl (AUS), Alan M. Watson (UNAM), Ny Avo Rakotondrainibe (LAM), Sarah Antier (OCA), Stéphane Basa (UAR Pytheas), William H. Lee (UNAM), Camila Angulo (UNAM), Jean-Luc Atteia (IRAP), Nathaniel R. Butler (ASU), Damien Dornic (CPPM), Francis Fortin (IRAP), Noémie Globus (UNAM), Francesco Magnani (CPPM), Margarita Pereyra (UNAM), and Benjamin Schneider (LAM) report: We imaged the field of the candidate reported by the Pan-STARRS Collaboration (Young et al. GCN 39210) of the optical transient AT 2025bbo reported as a possible counterpart of the GW transient S250206dm (LVK Collaboration, GCN Circ. 39175, GCN Circ. 39184) with the DDRAGO wide-field imager on the COLIBRÍ telescope at the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir in Mexico. We observed AT 2025bbo from 2025-02-09 03:47 to 04:44 (from T+2.27 to T+2.30 days after the GW transient), obtaining 600 seconds of exposure in both g and r. The data were reduced and stacked using custom software and then calibrated against the PS1 catalog and analysed using STDPipe (Karpov 2021). We carried out image subtraction against PS DR2 images. At the position of the source reported by Young et al., we detect the source at: r = 19.85 +/- 0.05 In agreement to the increase in the brightness reported by the Kinder (Lee et al., GCN Circ. 39252) and WFST collaborations (Smartt et al., GCN Circ. 39249). In g, the source is fainter than our 3-sigma limit of g > 21.1 This suggests that the source is red. Further observations are planned. Furthermore, we observed 10 galaxies in the MANGROVE catalog (Ducoin et al., 2020) in the 50% region of probability of S250206dm, consistent with the 90% containment volume. We observed between 2025-02-09 02:35 and 06:15 (from T+2.2 to T+2.4 days after the GW transient) and obtained 600 seconds of exposure in r on each galaxy. The data were reduced and stacked using custom software and then calibrated against the PS1 catalog and analysed using STDPipe (Karpov 2021). We carried out image subtraction against PS DR2 images. With one exception, we detect no possible candidates to the 10-sigma limits quoted below: | | Name | RA | Dec | 10-sigma limit | |---|---|---|---|---| | 1 | 2MASS 02242513+5242101 | 36.105 | 52.703 | r > 21.2 | | 2 | 2MASS 02353482+5315284 | 38.895 | 53.258 | r > 20.9 | | 3 | 2MASS 02292273+5329140 | 37.345 | 53.487 | r > 20.2 | | 4 | HyperLEDA 166437 | 40.104 | 54.253 | r > 20.8 | | 5 | 2MASS 02234887+5338542 | 35.954 | 53.648 | r > 20.8 | | 6 | 2MASS 02363571+5351138 | 39.149 | 53.854 | r > 20.6 | | 7 | 2MASS 02363578+5325108 | 39.149 | 53.420 | r > 20.9 | | 8 | 2MASS 02261049+5307282 | 36.544 | 53.125 | r > 19.8 | | 9 | 2MASS 02243083+5251021 | 36.128 | 52.851 | r > 20.7 | | 10 | 2MASS 02371899+5401539 | 39.329 | 54.032 | r > 20.6 | The one exception is that in the field of 2MASS 02363571+5351138 (galaxy 6 above), we detect a transient source 9-3 arcmin from the galaxy at RA = 39.27171 and Dec = 53.99079 degrees with a magnitude of r = 19.98 +/- 0.05. However, a source at the same position appears in the Pan-STARRS catalogs with g = 21.1 in DR1 and at several epochs at g = 22.5 in DR2. We interpret this as a variable star. Our photometry is not corrected for Galactic extinction. 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/39258. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 37267] IceCube Alert 250207.09: Global MASTER-Net observations report
by GCN Circulars 09 Feb '25

09 Feb '25

TITLE: GCN CIRCULAR NUMBER: 39257 SUBJECT: IceCube Alert 250207.09: Global MASTER-Net observations report DATE: 25/02/09 20:40:02 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-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the IceCube Alert 250207.09 (trigger No 78196104,08h 41m 03.60s , +17d 02m 34.8s, R=4.44) errorbox 14 sec after notice time and 68 sec after trigger time at 2025-02-07 02:09:04 UT, with upper limit up to 19.0 mag. The observations began at zenith distance = 75 deg. The sun altitude is -23.3 deg. MASTER-Tunka robotic telescope located in Russia (Applied Physics Institute, Irkutsk State University) started inspect of the IceCube Alert 250207.09 errorbox 42255 sec after notice time and 42309 sec after trigger time at 2025-02-07 13:53:05 UT, with upper limit up to 19.2 mag. The observations began at zenith distance = 45 deg. The sun altitude is -35.4 deg. The galactic latitude b = 32 deg., longitude l = 209 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2770114 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 74 | 2025-02-07 02:09:04 | MASTER-SAAO | (08h 40m 36.36s , +17d 03m 01.6s) | C | 10 | 17.3 | 94 | 2025-02-07 02:09:04 | MASTER-SAAO | (08h 40m 36.36s , +17d 03m 01.5s) | C | 50 | 18.3 | Coadd 108 | 2025-02-07 02:09:33 | MASTER-SAAO | (08h 40m 36.80s , +17d 03m 02.9s) | C | 20 | 17.9 | 147 | 2025-02-07 02:10:12 | MASTER-SAAO | (08h 40m 37.31s , +17d 03m 04.8s) | C | 20 | 17.8 | 191 | 2025-02-07 02:10:51 | MASTER-SAAO | (08h 40m 37.89s , +17d 03m 06.7s) | C | 30 | 18.0 | 245 | 2025-02-07 02:11:40 | MASTER-SAAO | (08h 40m 38.66s , +17d 03m 09.0s) | C | 40 | 18.1 | 309 | 2025-02-07 02:12:39 | MASTER-SAAO | (08h 40m 39.56s , +17d 03m 11.7s) | C | 50 | 18.1 | 383 | 2025-02-07 02:13:48 | MASTER-SAAO | (08h 40m 40.66s , +17d 03m 14.3s) | C | 60 | 18.1 | 462 | 2025-02-07 02:15:06 | MASTER-SAAO | (08h 40m 41.81s , +17d 03m 17.3s) | C | 60 | 18.1 | 541 | 2025-02-07 02:16:26 | MASTER-SAAO | (08h 40m 43.01s , +17d 03m 20.5s) | C | 60 | 18.0 | 620 | 2025-02-07 02:17:45 | MASTER-SAAO | (08h 40m 44.27s , +17d 03m 23.4s) | C | 60 | 18.0 | 699 | 2025-02-07 02:19:04 | MASTER-SAAO | (08h 40m 45.56s , +17d 03m 26.6s) | C | 60 | 17.9 | 778 | 2025-02-07 02:20:23 | MASTER-SAAO | (08h 40m 46.85s , +17d 03m 29.8s) | C | 60 | 17.9 | 857 | 2025-02-07 02:21:42 | MASTER-SAAO | (08h 40m 48.22s , +17d 03m 32.8s) | C | 60 | 17.9 | 936 | 2025-02-07 02:23:01 | MASTER-SAAO | (08h 40m 49.59s , +17d 03m 36.0s) | C | 60 | 17.8 | 1015 | 2025-02-07 02:24:20 | MASTER-SAAO | (08h 40m 51.02s , +17d 03m 38.9s) | C | 60 | 17.8 | 1094 | 2025-02-07 02:25:39 | MASTER-SAAO | (08h 40m 52.46s , +17d 03m 42.2s) | C | 60 | 17.7 | 1173 | 2025-02-07 02:26:58 | MASTER-SAAO | (08h 40m 53.93s , +17d 03m 45.3s) | C | 60 | 17.7 | 1252 | 2025-02-07 02:28:17 | MASTER-SAAO | (08h 40m 55.47s , +17d 03m 48.3s) | C | 60 | 17.6 | 1332 | 2025-02-07 02:29:36 | MASTER-SAAO | (08h 40m 57.02s , +17d 03m 51.7s) | C | 60 | 17.7 | 1411 | 2025-02-07 02:30:56 | MASTER-SAAO | (08h 40m 58.60s , +17d 03m 55.0s) | C | 60 | 17.6 | 1490 | 2025-02-07 02:32:15 | MASTER-SAAO | (08h 41m 00.22s , +17d 03m 58.3s) | C | 60 | 17.5 | 1569 | 2025-02-07 02:33:34 | MASTER-SAAO | (08h 41m 00.88s , +17d 04m 01.8s) | C | 60 | 18.3 | 1629 | 2025-02-07 02:33:34 | MASTER-SAAO | (08h 41m 00.88s , +17d 04m 01.8s) | C | 180 | 19.0 | Coadd 1649 | 2025-02-07 02:34:54 | MASTER-SAAO | (08h 41m 00.70s , +17d 04m 05.2s) | C | 60 | 18.3 | 1728 | 2025-02-07 02:36:12 | MASTER-SAAO | (08h 41m 00.53s , +17d 04m 08.4s) | C | 60 | 18.3 | 1807 | 2025-02-07 02:37:32 | MASTER-SAAO | (08h 41m 00.30s , +17d 04m 12.2s) | C | 60 | 18.3 | 1867 | 2025-02-07 02:37:32 | MASTER-SAAO | (08h 41m 00.29s , +17d 04m 12.1s) | C | 180 | 18.9 | Coadd 1886 | 2025-02-07 02:38:51 | MASTER-SAAO | (08h 41m 00.06s , +17d 04m 15.9s) | C | 60 | 18.3 | 1965 | 2025-02-07 02:40:10 | MASTER-SAAO | (08h 40m 59.84s , +17d 04m 19.2s) | C | 60 | 18.3 | 2044 | 2025-02-07 02:41:29 | MASTER-SAAO | (08h 40m 59.57s , +17d 04m 23.3s) | C | 60 | 18.2 | 2104 | 2025-02-07 02:41:29 | MASTER-SAAO | (08h 40m 59.56s , +17d 04m 23.4s) | C | 180 | 18.8 | Coadd 2123 | 2025-02-07 02:42:48 | MASTER-SAAO | (08h 40m 59.30s , +17d 04m 27.4s) | C | 60 | 18.2 | 2203 | 2025-02-07 02:44:07 | MASTER-SAAO | (08h 40m 59.02s , +17d 04m 31.8s) | C | 60 | 18.1 | 2281 | 2025-02-07 02:45:26 | MASTER-SAAO | (08h 40m 58.78s , +17d 04m 36.4s) | C | 60 | 18.1 | 2341 | 2025-02-07 02:45:26 | MASTER-SAAO | (08h 40m 58.77s , +17d 04m 36.5s) | C | 180 | 18.7 | Coadd 2361 | 2025-02-07 02:46:45 | MASTER-SAAO | (08h 40m 58.40s , +17d 04m 42.0s) | C | 60 | 18.0 | 2440 | 2025-02-07 02:48:05 | MASTER-SAAO | (08h 40m 58.05s , +17d 04m 47.5s) | C | 60 | 17.9 | 2519 | 2025-02-07 02:49:24 | MASTER-SAAO | (08h 40m 57.72s , +17d 04m 52.7s) | C | 60 | 17.9 | 2579 | 2025-02-07 02:49:24 | MASTER-SAAO | (08h 40m 57.72s , +17d 04m 52.7s) | C | 180 | 18.5 | Coadd 2599 | 2025-02-07 02:50:43 | MASTER-SAAO | (08h 40m 57.35s , +17d 04m 58.0s) | C | 60 | 17.8 | 2678 | 2025-02-07 02:52:03 | MASTER-SAAO | (08h 40m 56.91s , +17d 05m 03.9s) | C | 60 | 17.6 | 2757 | 2025-02-07 02:53:22 | MASTER-SAAO | (08h 40m 56.44s , +17d 05m 10.0s) | C | 60 | 17.4 | 2836 | 2025-02-07 02:54:41 | MASTER-SAAO | (08h 40m 56.01s , +17d 05m 15.8s) | C | 60 | 17.4 | 2915 | 2025-02-07 02:56:00 | MASTER-SAAO | (08h 40m 55.44s , +17d 05m 22.6s) | C | 60 | 16.8 | 2994 | 2025-02-07 02:57:19 | MASTER-SAAO | (08h 40m 54.71s , +17d 05m 32.1s) | C | 60 | 16.1 | 3074 | 2025-02-07 02:58:38 | MASTER-SAAO | (08h 40m 54.23s , +17d 05m 38.1s) | C | 60 | 15.4 | 3153 | 2025-02-07 02:59:57 | MASTER-SAAO | (08h 40m 53.73s , +17d 05m 43.7s) | C | 60 | 15.3 | 3231 | 2025-02-07 03:01:16 | MASTER-SAAO | (08h 40m 53.86s , +17d 05m 46.9s) | C | 60 | 12.1 | 42320 | 2025-02-07 13:53:05 | MASTER-Tunka | (08h 50m 13.23s , +20d 46m 32.3s) | C | 20 | 18.5 | 42340 | 2025-02-07 13:53:05 | MASTER-Tunka | (08h 50m 13.24s , +20d 46m 32.3s) | C | 60 | 19.2 | Coadd 42344 | 2025-02-07 13:53:28 | MASTER-Tunka | (08h 50m 13.23s , +20d 46m 33.0s) | C | 20 | 18.6 | 42367 | 2025-02-07 13:53:52 | MASTER-Tunka | (08h 50m 13.23s , +20d 46m 34.1s) | C | 20 | 18.5 | 42394 | 2025-02-07 13:54:16 | MASTER-Tunka | (08h 50m 13.22s , +20d 46m 35.3s) | C | 25 | 18.5 | 42423 | 2025-02-07 13:54:44 | MASTER-Tunka | (08h 50m 13.22s , +20d 46m 36.3s) | C | 25 | 18.5 | 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/39257. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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