August 2024 - vsnet-grb-info - ooruri.kusastro.kyoto-u.ac.jp

[vsnet-grb-info 34975] GRB 240801A: GRBAlpha detection
by GCN Circulars 08 Aug '24

08 Aug '24

TITLE: GCN CIRCULAR NUMBER: 37102 SUBJECT: GRB 240801A: GRBAlpha detection DATE: 24/08/08 16:15:32 GMT FROM: Jakub Ripa <ripa.jakub(a)gmail.com> J. Ripa, M. Dafcikova, M. Kolar (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner (Masaryk U.), M. Ohno, H. Takahashi (Hiroshima U.), L. Meszaros, B. Csak (Konkoly Observatory), N. Husarikova, F. Munz , M. Topinka, M. Duriskova, L. Szakszonova, J.-P. Breuer, F. Hroch (Masaryk U.), T. Urbanec, M. Kasal, A. Povalac (Brno U. of Technology), J. Hudec, J. Kapus, M. Frajt (Spacemanic s.r.o), R. Laszlo, M. Koleda (Needronix s.r.o), M. Smelko, P. Hanak, P. Lipovsky (Technical U. of Kosice), G. Galgoczi (Wigner Research Center/Eotvos U.), Y. Uchida, H. Poon, H. Matake (Hiroshima U.), N. Uchida (ISAS/JAXA), T. Bozoki (Eotvos U.), G. Dalya (Eotvos U.), T. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), G. Friss (Eotvos U.), Y. Fukazawa, K. Hirose (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), K. Kapas (Eotvos U.), L. L. Kiss (Konkoly Observatory), T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), J. Takatsy (Eotvos U.), K. Torigoe (Hiroshima U.), N. Kogiso, M. Yoneyama (Osaka Metropolitan U.), M. Moritaki (U. Tokyo), T. Kano (U. Michigan) -- the GRBAlpha collaboration. The long-duration GRB 240801A (Fermi/GBM detection: GCN 36994) was observed by the GRBAlpha 1U CubeSat (Pal et al. 2023, A&A, 677, 40; https://ui.adsabs.harvard.edu/abs/2023A%26A...677A..40P/abstract). The detection was confirmed at the peak time 2024-08-01 03:18:33.1 UTC. The T90 duration measured by GRBAlpha is 13.0 s and the overall significance during T90 reaches 9.6 sigma. The light curve obtained by GRBAlpha is available here: https://grbalpha.konkoly.hu/static/share/GRB240801A_GCN.pdf All GRBAlpha detections are listed at: https://monoceros.physics.muni.cz/hea/GRBAlpha/ GRBAlpha, launched on 2021 March 22, is a demonstration mission for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). The detector of GRBAlpha consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~50 keV to ~1000 keV. To increase the duty cycle and the downlink rate, the upgrade of the on-board data acquisition software stack is in progress. The ground segment is also supported by the radio amateur community and it takes advantage of the SatNOGS network for increased data downlink volume. View this GCN Circular online at https://gcn.nasa.gov/circulars/37102. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34974] GRB 240807B: Fermi GBM Final Localization
by GCN Circulars 08 Aug '24

08 Aug '24

TITLE: GCN CIRCULAR NUMBER: 37101 SUBJECT: GRB 240807B: Fermi GBM Final Localization DATE: 24/08/08 14:20:13 GMT FROM: sumanbala2210(a)gmail.com The Fermi GBM team reports the detection of a likely SHORT GRB "At 22:04:13.59 UT on 07 August 2024, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 240807B (trigger 744761058/240807920). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 297.35, Dec = -42.71 (J2000 degrees, equivalent to J2000 19h 49m, -42d 42'), with a statistical uncertainty of 7.82 degrees. The angle from the Fermi LAT boresight is 64 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2024/bn240807920/… The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2024/bn240807920/… The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2024/bn240807920/…" View this GCN Circular online at https://gcn.nasa.gov/circulars/37101. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34973] GRB 240710B: VZLUSAT-2 detection
by GCN Circulars 08 Aug '24

08 Aug '24

TITLE: GCN CIRCULAR NUMBER: 37100 SUBJECT: GRB 240710B: VZLUSAT-2 detection DATE: 24/08/08 09:15:34 GMT FROM: Marianna Dafčíková at Masaryk University <500025(a)mail.muni.cz> M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner (Masaryk U.), M. Ohno (Hiroshima U.), L. Meszaros, B. Csak (Konkoly Observatory), H. Takahashi (Hiroshima U.), F. Munz , M. Topinka, F. Hroch, N. Husarikova, J.-P. Breuer (Masaryk U.), J. Hudec, J. Kapus, M. Frajt, M. Rezenov (Spacemanic s.r.o), R. Laszlo (Needronix), G. Galgoczi (Wigner Research Center/Eotvos U.), N. Uchida (ISAS/JAXA), T. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), Y. Fukazawa, K. Hirose, H. Matake (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), L. L. Kiss (Konkoly Observatory), T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), K. Torigoe (Hiroshima U.), P. Svoboda, V. Daniel, J. Dudas, M. Junas, J. Gromes (VZLU), I. Vertat (FEL ZCU) -- the VZLUSAT-2/GRB payload collaboration. The long-duration GRB 240710B (Fermi/GBM detection: trigger no. 742317942; Konus/Wind detection trigger at 2024-07-10 15:25:41.692 UTC; GRBAlpha detection: GCN 36953) was detected by the GRB detector on board of the VZLUSAT-2 3U CubeSat (https://www.vzlusat2.cz/en/). The data acquisition was performed by the GRB detector unit no. 1. The detection was confirmed at the peak time 2024-07-10 15:25:37 UTC. The T90 duration is 5 s and the significance during T90 reaches 27 sigma. The light curve obtained by VZLUSAT-2 is available here: https://vzlusat2.konkoly.hu/static/share/GRB240710B_GCN_VZLUSAT2.pdf All VZLUSAT-2 detections are listed at: https://monoceros.physics.muni.cz/hea/VZLUSAT-2/ The GRB detectors on VZLUSAT-2 are a demonstration payload for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). Two GRB modules of VZLUSAT-2 are placed in a perpendicular manner and each consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~30 keV to ~1000 keV. VZLUSAT-2 was launched on 2022 January 13 from Cape Canaveral. View this GCN Circular online at https://gcn.nasa.gov/circulars/37100. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34972] GRB 240805A: ATCA Radio Upper Limits
by GCN Circulars 08 Aug '24

08 Aug '24

TITLE: GCN CIRCULAR NUMBER: 37099 SUBJECT: GRB 240805A: ATCA Radio Upper Limits DATE: 24/08/08 07:19:40 GMT FROM: agul8829(a)uni.sydney.edu.au A. Gulati (USyd), S. Chastain (UNM), G. E. Anderson (Curtin), J. K. Leung (UofT/HUJI), S. D. Ryder (Macquarie), A. J. van der Horst (GWU), and L. Rhodes (Oxford) on behalf of the ATCA PanRadio GRB collaboration We observed long GRB 240805A (Fermi GBM Collaboration, GCN 37031; S. Dichiara et al., GCN 37032) as part of the The Australia Telescope Compact Array (ATCA) "PanRadio GRB" Large Project C3542 (PI: G. Anderson) at 5.5 and 9 GHz 18-minutes post burst on 2024-08-05 (02:30-13:30 UT) and 2.7 days post-burst on 2024-08-07 (09:00-13:00 UT). No radio sources were detected near the Swift/XRT enhanced position (J. P. Osborne et al., GCN 37045) in either observation epoch. The 3-sigma upper limits for the 9 GHz observations are 45 and 42 uJy respectively. We thank the CSIRO Space and Astronomy staff for supporting these observations. We acknowledge the Gomeroi people as the traditional owners of the Observatory site. The Australia Telescope Compact Array is part of the Australia Telescope National Facility (https://ror.org/05qajvd42) which is funded by the Australian Government for operation as a National Facility managed by CSIRO. View this GCN Circular online at https://gcn.nasa.gov/circulars/37099. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34971] Fermi trigger No 744761058: Global MASTER-Net observations report
by GCN Circulars 08 Aug '24

08 Aug '24

TITLE: GCN CIRCULAR NUMBER: 37098 SUBJECT: Fermi trigger No 744761058: Global MASTER-Net observations report DATE: 24/08/08 03:30:32 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov(a)xray.sai.msu.ru> V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko, G.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij (Lomonosov Moscow State University, SAI, Physics Department), R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA), R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias), D. Buckley (South African Astronomical Observatory), O.A. Gress, N.M. Budnev, O.Ershova (Irkutsk State University, API), L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), V. Yurkov, A. Gabovich (Blagoveschensk Educational State University) 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 Fermi GRB240807.92 (trigger No 744761058,20h 17m 28.80s , -48d 16m 12.0s, R=9.87) errorbox 15438 sec after notice time and 15443 sec after trigger time at 2024-08-08 02:21:37 UT, with upper limit up to 19.1 mag. The observations began at zenith distance = 50 deg. The sun altitude is -38.5 deg. The galactic latitude b = -34 deg., longitude l = 351 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2554750 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 15474 | 2024-08-08 02:21:37 | MASTER-SAAO | (20h 36m 35.52s , -48d 23m 07.0s) | C | 60 | 19.0 | 15636 | 2024-08-08 02:24:19 | MASTER-SAAO | (20h 25m 04.88s , -50d 14m 36.6s) | C | 60 | 19.1 | 15715 | 2024-08-08 02:25:38 | MASTER-SAAO | (20h 37m 40.10s , -50d 16m 19.0s) | C | 60 | 19.1 | 15873 | 2024-08-08 02:28:16 | MASTER-SAAO | (20h 01m 41.13s , -48d 19m 19.4s) | C | 60 | 19.0 | 15953 | 2024-08-08 02:29:36 | MASTER-SAAO | (20h 13m 43.24s , -48d 21m 14.8s) | C | 60 | 19.0 | 16111 | 2024-08-08 02:32:14 | MASTER-SAAO | (20h 01m 18.12s , -50d 12m 53.5s) | C | 60 | 19.0 | 16191 | 2024-08-08 02:33:34 | MASTER-SAAO | (20h 13m 54.55s , -50d 14m 35.8s) | C | 60 | 19.1 | 16270 | 2024-08-08 02:34:53 | MASTER-SAAO | (20h 24m 29.59s , -48d 22m 11.4s) | C | 60 | 19.1 | 16439 | 2024-08-08 02:37:42 | MASTER-SAAO | (20h 36m 34.61s , -48d 21m 16.0s) | C | 60 | 19.1 | 16598 | 2024-08-08 02:40:21 | MASTER-SAAO | (20h 25m 10.15s , -50d 14m 17.6s) | C | 60 | 19.1 | 16677 | 2024-08-08 02:41:40 | MASTER-SAAO | (20h 37m 34.39s , -50d 15m 46.0s) | C | 60 | 19.1 | 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/37098. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34970] EP240807a/GRB 240807A: EP-FXT detection of the X-ray emission
by GCN Circulars 08 Aug '24

08 Aug '24

TITLE: GCN CIRCULAR NUMBER: 37097 SUBJECT: EP240807a/GRB 240807A: EP-FXT detection of the X-ray emission DATE: 24/08/08 03:01:27 GMT FROM: EP Team at NAOC/CAS <ep_ta(a)bao.ac.cn> J. W. Hu, S. Q. Jiang (NAOC, CAS), Y. C. Fu (BNU) , Z. X. Ling, W. D. Zhang, Y. Liu, C. C. Jin, C. Zhang, H. Q. Cheng, W. Chen, C. Z. Cui, D. W. Fan, H. B. Hu, M. H. Huang, D. Y. Li, H. Y. Liu, M. J. Liu, Z. Z. Lv, T. Y. Lian, X. Mao, H. W. Pan, X. Pan, H. Sun, W. X. Wang, Y. L. Wang, Q. Y. Wu, X. P. Xu, Y. F. Xu, H. N. Yang, W. Yuan, M. Zhang, W. J. Zhang, Z. Zhang, D. H. Zhao (NAOC, CAS), Y. Chen, S. M. Jia, W. W. Cui, D. W. Han, C. K. Li, L. M. Song, X. F. Zhao, J. Zhang, S. N. Zhang (IHEP, CAS), E. Kuulkers, A. Santovincenzo (ESA), P. O'Brien (Univ. of Leicester), K. Nandra, A. Rau (MPE), B. Cordier (CEA) on behalf of the Einstein Probe team Following the detection of the fast X-ray transient EP240807a (trigger ID 11908397839; Fu et al., GCN 37088), which was temporally coincident with GRB 240807A (Fermi GBM team, GCN 37089), we performed an observation of EP240807a with the Follow-up X-ray Telescope (FXT) on board the Einstein Probe (EP) mission. The observation began at 2024-08-07T13:23:29 UTC, about 7.7 hours after the EP-WXT detection. The exposure time is 4434 seconds. Within the error circle of the WXT source, an X-ray source was detected at R.A. = 300.9668 deg, DEC = -68.7861 deg, with an uncertainty of 10 arcsec (radius, 90% C.L. statistical and systematic). The average 0.5-10 keV spectrum can be fitted with an absorbed power law with a photon index of 1.65(-0.38, +0.39) (with a fixed Galactic column density value of 5 x 10^20 cm^-2). The derived average unabsorbed 0.5-10 keV flux is 2.8(-0.8, +1.4) x 10^(-13) erg/s/cm^2. There is no cataloged X-ray source within the error circle, suggesting this source being associated with EP240807a. 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/37097. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34969] S240807h: Identification of a GW compact binary merger candidate
by GCN Circulars 07 Aug '24

07 Aug '24

TITLE: GCN CIRCULAR NUMBER: 37096 SUBJECT: S240807h: Identification of a GW compact binary merger candidate DATE: 24/08/07 22:31:32 GMT FROM: samantha.callos(a)ligo.org The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report: We identified the compact binary merger candidate S240807h during real-time processing of data from LIGO Livingston Observatory (L1) and Virgo Observatory (V1) at 2024-08-07 21:45:59.197 UTC (GPS time: 1407102377.197). The candidate was found by the GstLAL [1] analysis pipeline. S240807h is an event of interest because its false alarm rate, as estimated by the online analysis, is 2e-11 Hz, or about one in 1e3 years. The event's properties can be found at this URL: https://gracedb.ligo.org/superevents/S240807h The classification of the GW signal, in order of descending probability, is BBH (>99%), NSBH (<1%), Terrestrial (<1%), or BNS (<1%). Assuming the candidate is astrophysical in origin, the probability that the lighter compact object is consistent with a neutron star mass (HasNS) is <1%. [2] Using the masses and spins inferred from the signal, the probability of matter outside the final compact object (HasRemnant) is <1%. [2] Both HasNS and HasRemnant consider the support of several neutron star equations of state. The probability that either of the binary components lies between 3 and 5 solar masses (HasMassGap) is 4%. Two sky maps are available at this time and can be retrieved from the GraceDB event page: * bayestar.multiorder.fits,0, an initial localization generated by BAYESTAR [3], distributed via GCN notice about 26 seconds after the candidate event time. * bayestar.multiorder.fits,1, an initial localization generated by BAYESTAR [3], distributed via GCN notice about 5 minutes after the candidate event time. The preferred sky map at this time is bayestar.multiorder.fits,1. For the bayestar.multiorder.fits,1 sky map, the 90% credible region is 13078 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 1051 +/- 326 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] Tsukada et al. PRD 108, 043004 (2023) doi:10.1103/PhysRevD.108.043004 and Ewing et al. (2023) arXiv:2305.05625 [2] Chatterjee et al. ApJ 896, 54 (2020) doi:10.3847/1538-4357/ab8dbe [3] Singer & Price PRD 93, 024013 (2016) doi:10.1103/PhysRevD.93.024013 View this GCN Circular online at https://gcn.nasa.gov/circulars/37096. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34968] EP-WXT trigger 01709018832: KAIT optical observations of the star flare
by GCN Circulars 07 Aug '24

07 Aug '24

TITLE: GCN CIRCULAR NUMBER: 37095 SUBJECT: EP-WXT trigger 01709018832: KAIT optical observations of the star flare DATE: 24/08/07 22:01:22 GMT FROM: Weikang Zheng at UC Berkeley <weikang(a)berkeley.edu> WeiKang Zheng (UCB), Xuhui Han (NAOC), Pinpin Zhang (NAOC) and Alexei V. Filippenko (UCB) report on behalf of the KAIT GRB team: The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at Lick Observatory, automatically responded to the fast X-ray transient WXT trigger 01709018832 from the Einstein Probe (Jiang et al. GCNC 37090) starting at 06:49 UT, 27 minutes after the trigger. A set of clear (roughly R) filter images were obtained. We do not detect any new optical counterpart in the EP/FXT errorbox (Jiang et al. GCNC 37090). However, the star within the EP/FXT errorbox (Gaia DR3 2445442335531658752), as pointed out by Jiang et al. (GCNC 37090), was clearly detected in all of our images. Photometry shows its magnitude steadily decayed from ~15.1 mag at ~0.46 hours to ~16.2 mag at ~5.26 hours after the trigger. We thus confirm WXT trigger 01709018832 is truly from this star flare, consistent with the X-ray flare from the same star as suggested by Jiang et al. (GCNC 37090). View this GCN Circular online at https://gcn.nasa.gov/circulars/37095. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34967] EP240802a/GRB240802A: KAIT optical upper limit
by GCN Circulars 07 Aug '24

07 Aug '24

TITLE: GCN CIRCULAR NUMBER: 37094 SUBJECT: EP240802a/GRB240802A: KAIT optical upper limit DATE: 24/08/07 19:47:10 GMT FROM: Weikang Zheng at UC Berkeley <weikang(a)berkeley.edu> WeiKang Zheng (UCB), Xuhui Han (NAOC), Pinpin Zhang (NAOC) and Alexei V. Filippenko (UCB) report on behalf of the KAIT GRB team: The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at Lick Observatory, responded to the fast X-ray transient EP240802a from the Einstein Probe (Wang et al. GCNC 37019) starting at 04:17 UT, Aug 3rd, ~0.74 days after the trigger. EP240802a was also found to be coincidence with GRB 240802A (Waratkar et al., GCN 37018; Aryan et al., GCN 37021; Kozyrev et al., GCN 37078). We obtained a set of clear (roughly R) filter images, we do not detect any new optical counterpart in the FXT errorbox (Wang et al. GCNC 37019), neither in single image, nor in the co-add images. We measure the limiting mag to be ~21.0 in 28x60s co-add image at a mid time of ~0.80 days after the trigger. Our result is consistent with the upper limit reported from Aryan et al. (GCN 37021), Quadri et al. (GCN 37023) and Leonini et al. (GCN 37029). View this GCN Circular online at https://gcn.nasa.gov/circulars/37094. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34966] GRB 240720B: VZLUSAT-2 detection
by GCN Circulars 07 Aug '24

07 Aug '24

TITLE: GCN CIRCULAR NUMBER: 37093 SUBJECT: GRB 240720B: VZLUSAT-2 detection DATE: 24/08/07 17:59:37 GMT FROM: Marianna Dafčíková at Masaryk University <500025(a)mail.muni.cz> M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner (Masaryk U.), M. Ohno (Hiroshima U.), L. Meszaros, B. Csak (Konkoly Observatory), H. Takahashi (Hiroshima U.), F. Munz , M. Topinka, F. Hroch, N. Husarikova, J.-P. Breuer (Masaryk U.), J. Hudec, J. Kapus, M. Frajt, M. Rezenov (Spacemanic s.r.o), R. Laszlo (Needronix), G. Galgoczi (Wigner Research Center/Eotvos U.), N. Uchida (ISAS/JAXA), T. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), Y. Fukazawa, K. Hirose, H. Matake (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), L. L. Kiss (Konkoly Observatory), T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), K. Torigoe (Hiroshima U.), P. Svoboda, V. Daniel, J. Dudas, M. Junas, J. Gromes (VZLU), I. Vertat (FEL ZCU) -- the VZLUSAT-2/GRB payload collaboration. The short-duration GRB 240720B (AstroSat/CZTI detection: GCN 36913; SVOM/GRM detection: GCN 36915; GRBAlpha detection: GCN 36955; INTEGRAL/SPI-ACS detection: trigger no. 10798; Konus/Wind detection trigger at 2024-07-20 16:11:28.495 UTC) was detected by the GRB detectors on board of the VZLUSAT-2 3U CubeSat (https://www.vzlusat2.cz/en/). The data acquisition was performed by the GRB detector units no. 0 and no. 1. The detection was confirmed at the peak time 2024-07-20 16:11:22 UTC. The T90 duration is 1 s (1 s) and the significance during T90 reaches 11 sigma (12 sigma) for detector unit no. 0 (no. 1). The light curve obtained by VZLUSAT-2 is available here: https://vzlusat2.konkoly.hu/static/share/GRB240720B_GCN_VZLUSAT2.pdf All VZLUSAT-2 detections are listed at: https://monoceros.physics.muni.cz/hea/VZLUSAT-2/ The GRB detectors on VZLUSAT-2 are a demonstration payload for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). Two GRB modules of VZLUSAT-2 are placed in a perpendicular manner and each consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~30 keV to ~1000 keV. VZLUSAT-2 was launched on 2022 January 13 from Cape Canaveral. View this GCN Circular online at https://gcn.nasa.gov/circulars/37093. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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