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

[vsnet-grb-info 34370] LIGO/Virgo/KAGRA S240515m: Upper limits from Swift/BAT-GUANO
by GCN Circulars 21 May '24

21 May '24

TITLE: GCN CIRCULAR NUMBER: 36526 SUBJECT: LIGO/Virgo/KAGRA S240515m: Upper limits from Swift/BAT-GUANO DATE: 24/05/21 03:38:41 GMT FROM: Samuele Ronchini at PSU <sjs8171(a)psu.edu> Samuele Ronchini (PSU), Gayathri Raman (PSU), Jamie A. Kennea (PSU), Tyler Parsotan (NASA GSFC), Aaron Tohuvavohu (U Toronto), James DeLaunay (PSU) report: Swift/BAT was observing 92% of the GW localization probability (bayestar.multiorder.fits) at merger time. A fraction 33% of the GW localization posterior is contained inside the BAT coded FoV. The LVK notice, distributed in near real-time, triggered the Swift Mission Operations Center operated Gamma-ray Urgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1). Upon trigger by this notice, GUANO sent a command to the Swift Burst Alert Telescope (BAT) to save 200 seconds of BAT event-mode data from [-50,+150] seconds around the time of the burst. All the requested event mode data was delivered to the ground. Using the NITRATES analysis (DeLaunay + Tohuvavohu 2022, ApJ, 941, 169), we searched for emission on 8 timescales from 0.128s to 16.384s in the interval [-20,+20] seconds around the merger time. We find no evidence for a signal, and derive the following upper limits. We quote the 5-sigma flux upper limits in the 15-350 keV band, weighted over the GW localization, for four spectral templates (soft, normal, and hard GRB-like templates described in [arXiv:1612.02395], and spectral shape from GRB170817A [arXiv:1710.05446]) and for four time bins. In units of 10^-7 erg/s/cm^2: time_bin (s) soft normal hard GRB170817 ------------------------------------ 0.256 7.25 5.67 5.31 6.02 1.024 3.72 2.92 2.73 3.10 4.096 2.05 1.61 1.51 1.71 16.384 1.33 1.04 0.97 1.10 The upper limits as function of sky position are plotted here, alongside the GW localization: https://doi.org/10.5281/zenodo.11225725 The solid and dashed lines indicate the 90% and 50% GW contour levels, respectively. The corresponding fits file is also included. GUANO is a fully autonomous, extremely low latency, spacecraft commanding pipeline designed for targeted recovery of BAT event mode data around the times of compelling astrophysical events to enable more sensitive GRB searches. A live reporting of Swift/BAT event data recovered by GUANO can be found at: https://www.swift.psu.edu/guano/ View this GCN Circular online at https://gcn.nasa.gov/circulars/36526. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34369] LIGO/Virgo/KAGRA S240514x: Upper limits from Swift/BAT-GUANO
by GCN Circulars 21 May '24

21 May '24

TITLE: GCN CIRCULAR NUMBER: 36525 SUBJECT: LIGO/Virgo/KAGRA S240514x: Upper limits from Swift/BAT-GUANO DATE: 24/05/21 03:38:38 GMT FROM: Samuele Ronchini at PSU <sjs8171(a)psu.edu> Samuele Ronchini (PSU), Jamie A. Kennea (PSU), Tyler Parsotan (NASA GSFC), Aaron Tohuvavohu (U Toronto), Gayathri Raman (PSU), James DeLaunay (PSU) report: Swift/BAT was observing 62% of the GW localization probability (bayestar.multiorder.fits) at merger time. A fraction 0.0% of the GW localization posterior is contained inside the BAT coded FoV. The LVK notice, distributed in near real-time, triggered the Swift Mission Operations Center operated Gamma-ray Urgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1). Upon trigger by this notice, GUANO sent a command to the Swift Burst Alert Telescope (BAT) to save 200 seconds of BAT event-mode data from [-50,+150] seconds around the time of the burst. All the requested event mode data was delivered to the ground. Using the NITRATES analysis (DeLaunay + Tohuvavohu 2022, ApJ, 941, 169), we searched for emission on 8 timescales from 0.128s to 16.384s in the interval [-20,+20] seconds around the merger time. We find no evidence for a signal, and derive the following upper limits. We quote the 5-sigma flux upper limits in the 15-350 keV band, weighted over the GW localization, for four spectral templates (soft, normal, and hard GRB-like templates described in [arXiv:1612.02395], and spectral shape from GRB170817A [arXiv:1710.05446]) and for four time bins. In units of 10^-7 erg/s/cm^2: time_bin (s) soft normal hard GRB170817 ------------------------------------ 0.256 28.9 19.9 17.6 22.3 1.024 14.8 10.2 8.97 11.4 4.096 7.92 5.45 4.81 6.11 16.384 4.87 3.35 2.95 3.75 The upper limits as function of sky position are plotted here, alongside the GW localization: https://doi.org/10.5281/zenodo.11225695 The solid and dashed lines indicate the 90% and 50% GW contour levels, respectively. The corresponding fits file is also included. GUANO is a fully autonomous, extremely low latency, spacecraft commanding pipeline designed for targeted recovery of BAT event mode data around the times of compelling astrophysical events to enable more sensitive GRB searches. A live reporting of Swift/BAT event data recovered by GUANO can be found at: https://www.swift.psu.edu/guano/ View this GCN Circular online at https://gcn.nasa.gov/circulars/36525. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34368] LIGO/Virgo/KAGRA S240513ei: Upper limits from Swift/BAT-GUANO
by GCN Circulars 21 May '24

21 May '24

TITLE: GCN CIRCULAR NUMBER: 36524 SUBJECT: LIGO/Virgo/KAGRA S240513ei: Upper limits from Swift/BAT-GUANO DATE: 24/05/21 03:38:34 GMT FROM: Samuele Ronchini at PSU <sjs8171(a)psu.edu> Samuele Ronchini (PSU), Tyler Parsotan (NASA GSFC), Aaron Tohuvavohu (U Toronto), Gayathri Raman (PSU), James DeLaunay (PSU), Jamie A. Kennea (PSU) report: Swift/BAT was observing 97% of the GW localization probability (bayestar.multiorder.fits) at merger time. A fraction 0.3% of the GW localization posterior is contained inside the BAT coded FoV. The LVK notice, distributed in near real-time, triggered the Swift Mission Operations Center operated Gamma-ray Urgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1). Upon trigger by this notice, GUANO sent a command to the Swift Burst Alert Telescope (BAT) to save 200 seconds of BAT event-mode data from [-50,+150] seconds around the time of the burst. All the requested event mode data was delivered to the ground. Using the NITRATES analysis (DeLaunay + Tohuvavohu 2022, ApJ, 941, 169), we searched for emission on 8 timescales from 0.128s to 16.384s in the interval [-20,+20] seconds around the merger time. We find no evidence for a signal, and derive the following upper limits. We quote the 5-sigma flux upper limits in the 15-350 keV band, weighted over the GW localization, for four spectral templates (soft, normal, and hard GRB-like templates described in [arXiv:1612.02395], and spectral shape from GRB170817A [arXiv:1710.05446]) and for four time bins. In units of 10^-7 erg/s/cm^2: time_bin (s) soft normal hard GRB170817 ------------------------------------ 0.256 23.9 15.5 13.6 17.5 1.024 12.2 7.91 6.93 8.93 4.096 6.58 4.26 3.74 4.81 16.384 4.12 2.67 2.34 3.01 The upper limits as function of sky position are plotted here, alongside the GW localization: https://doi.org/10.5281/zenodo.11225647 The solid and dashed lines indicate the 90% and 50% GW contour levels, respectively. The corresponding fits file is also included. GUANO is a fully autonomous, extremely low latency, spacecraft commanding pipeline designed for targeted recovery of BAT event mode data around the times of compelling astrophysical events to enable more sensitive GRB searches. A live reporting of Swift/BAT event data recovered by GUANO can be found at: https://www.swift.psu.edu/guano/ View this GCN Circular online at https://gcn.nasa.gov/circulars/36524. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34367] LIGO/Virgo/KAGRA S240520cv: Identification of a GW compact binary merger candidate
by GCN Circulars 20 May '24

20 May '24

TITLE: GCN CIRCULAR NUMBER: 36523 SUBJECT: LIGO/Virgo/KAGRA S240520cv: Identification of a GW compact binary merger candidate DATE: 24/05/20 22:16:25 GMT FROM: Minhyo at Sungkyunkwan University <minhyo.kim(a)ligo.org> The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report: We identified the compact binary merger candidate S240520cv during real-time processing of data from LIGO Hanford Observatory (H1), LIGO Livingston Observatory (L1), and Virgo Observatory (V1) at 2024-05-20 21:36:16.965 UTC (GPS time: 1400276194.965). The candidate was found by the GstLAL [1], MBTA [2], and PyCBC Live [3] analysis pipelines. S240520cv is an event of interest because its false alarm rate, as estimated by the online analysis, is 3.2e-10 Hz, or about one in 1e2 years. The event's properties can be found at this URL: https://gracedb.ligo.org/superevents/S240520cv The classification of the GW signal, in order of descending probability, is BBH (97%), NSBH (3%), 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%. [4] Using the masses and spins inferred from the signal, the probability of matter outside the final compact object (HasRemnant) is <1%. [4] 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 5%. 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 [5], distributed via GCN notice about 31 seconds after the candidate event time. * bayestar.multiorder.fits,1, an initial localization generated by BAYESTAR [5], 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 370 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 1289 +/- 332 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] Aubin et al. CQG 38, 095004 (2021) doi:10.1088/1361-6382/abe913 [3] Dal Canton et al. ApJ 923, 254 (2021) doi:10.1088/1361-6382/abe913 [4] Chatterjee et al. ApJ 896, 54 (2020) doi:10.3847/1538-4357/ab8dbe [5] Singer & Price PRD 93, 024013 (2016) doi:10.1103/PhysRevD.93.024013 View this GCN Circular online at https://gcn.nasa.gov/circulars/36523. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34366] IceCube-Cascade 240518A: Upper limits from a search for additional neutrino events in IceCube
by GCN Circulars 20 May '24

20 May '24

TITLE: GCN CIRCULAR NUMBER: 36522 SUBJECT: IceCube-Cascade 240518A: Upper limits from a search for additional neutrino events in IceCube DATE: 24/05/20 18:36:56 GMT FROM: Jessie Thwaites at IceCube/U Wisc-Madison <thwaites(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-Cascade 240518A (https://gcn.gsfc.nasa.gov/notices_amon_icecube_cascade/139414_34468187.amon) in a time range of 1000 seconds centered on the alert event time (2024-05-18 06:41:47.880 UTC to 2024-05-18 06:58:27.880 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-Cascade 240518A. 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-Cascade 240518A ranges from 1.3e-01 to 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 1e+05 GeV. A subsequent search was performed including 2 days of data centered on the alert event time (2024-05-17 06:50:07.880 UTC to 2024-05-19 06:50:07.880 UTC). In this case, we report a p-value of 0.72, 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-Cascade 240518A ranges from 1.5e-01 to 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/36522. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34365] GRB 240514B: VZLUSAT-2 detection
by GCN Circulars 20 May '24

20 May '24

TITLE: GCN CIRCULAR NUMBER: 36521 SUBJECT: GRB 240514B: VZLUSAT-2 detection DATE: 24/05/20 15:21:26 GMT FROM: Andras Pal at Konkoly Observatory <apal(a)szofi.net> A. Pal (Konkoly Observatory), M. Dafcikova, J. Ripa, 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 240514B (Fermi/GBM detection: GCN 36481; GRBAlpha detection: GCN 36484; INTEGRAL/SPI-ACS peak detection at 2024-05-14 ~04:03:45 UT) 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 2024-05-14 04:03:34 UTC. The T90 duration is 1 s and the significance during T90 reaches 10 sigma. The light curve obtained by VZLUSAT-2 is available here: https://vzlusat2.konkoly.hu/static/share/GRB240514B_GCN_VZLUSAT2.pdf We note that the light curve measured by VZLUSAT-2 is shifted by approximately 11 s with respect to light curves obtained by other missions. The cause of the on-board clock slip is being fixed. 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/36521. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34364] GRB 240504A: VZLUSAT-2 detection
by GCN Circulars 20 May '24

20 May '24

TITLE: GCN CIRCULAR NUMBER: 36520 SUBJECT: GRB 240504A: VZLUSAT-2 detection DATE: 24/05/20 15:19:37 GMT FROM: Andras Pal at Konkoly Observatory <apal(a)szofi.net> A. Pal (Konkoly Observatory), M. Dafcikova, J. Ripa, 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 240504A (Fermi/GBM detection: GCN 36416; Swift/BAT-GUANO detection: GCN 36401; Konus/Wind detection trigger at 2024-05-04 05:12:49.901 UT; INTEGRAL/SPI-ACS peak detection at 2024-05-04 ~04:03:45 UT) 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 2024-05-04 05:12:51 (05:12:52) UTC. The T90 duration is 15 s (13 s) and the significance during T90 reaches 24 sigma (14 sigma) for detector unit no. 0 (no. 1). The light curve obtained by VZLUSAT-2 is available here: https://vzlusat2.konkoly.hu/static/share/GRB240504A_GCN_VZLUSAT2.pdf We note that the light curve measured by VZLUSAT-2 is shifted by approximately 8 s with respect to light curves obtained by other missions. The cause of the on-board clock slip is being fixed. 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/36520. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34363] GRB 240502A: VZLUSAT-2 detection
by GCN Circulars 20 May '24

20 May '24

TITLE: GCN CIRCULAR NUMBER: 36519 SUBJECT: GRB 240502A: VZLUSAT-2 detection DATE: 24/05/20 15:18:38 GMT FROM: Andras Pal at Konkoly Observatory <apal(a)szofi.net> A. Pal (Konkoly Observatory), M. Dafcikova, J. Ripa, 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 240502A (Fermi/GBM detection: GCN 36368; INTEGRAL/IBIS detection: GCN 36369) 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 2024-05-02 05:28:34 UTC. The T90 duration is 9 s and the significance during T90 reaches 5.9 sigma. The light curve obtained by VZLUSAT-2 is available here: https://vzlusat2.konkoly.hu/static/share/GRB240502A_GCN_VZLUSAT2.pdf We note that the light curve measured by VZLUSAT-2 is shifted by approximately 5 s with respect to light curves obtained by other missions. The cause of the on-board clock slip is being fixed. 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/36519. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34362] GRB 240519A: GRBAlpha detection
by GCN Circulars 20 May '24

20 May '24

TITLE: GCN CIRCULAR NUMBER: 36518 SUBJECT: GRB 240519A: GRBAlpha detection DATE: 24/05/20 15:17:11 GMT FROM: Andras Pal at Konkoly Observatory <apal(a)szofi.net> A. Pal (Konkoly Observatory), J. Ripa, M. Dafcikova, M. Kolar, 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 240519A (Fermi/GBM detection: GCN 36513; AstroSat/CZTI detection: GCN 36516) 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 2024-05-19 05:07:00.6 UTC. The T90 duration measured by GRBAlpha is 1.5 s and the overall significance during T90 reaches 5.9 sigma. The light curve obtained by GRBAlpha is available here: https://grbalpha.konkoly.hu/static/share/GRB240519A_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/36518. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34361] GRB 240516A: Swift/UVOT Upper Limits
by GCN Circulars 20 May '24

20 May '24

TITLE: GCN CIRCULAR NUMBER: 36517 SUBJECT: GRB 240516A: Swift/UVOT Upper Limits DATE: 24/05/20 13:03:20 GMT FROM: Sam Shilling at Lancaster University <shilling.sam(a)gmail.com> S. P. R. Shilling (Lancaster U.), S. R. Oates (Lancaster U.), N. P. Kuin (UCL-MSSL), A. A. Breeveld (UCL-MSSL) and T. M. Parsotan (GSFC) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 240516A 150 s after the BAT trigger (Parsotan et al., GCN Circ. 36493). No optical afterglow consistent with the XRT position (Parsotan et al., GCN Circ. 36493) is detected in the initial UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the initial exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white_FC 151 153 2 >17.8 white 150 1689 90 >19.9 v 5228 5427 197 >18.9 m2 5432 5632 197 >18.9 w1 5638 5838 197 >19.1 u 5843 5948 104 >19.1 We note that the first orbit of data only contained observations in the white filter. The other filters are from a later orbit of data. The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 2.390 in the direction of the burst (Schlegel et al. 1998). View this GCN Circular online at https://gcn.nasa.gov/circulars/36517. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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