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

[vsnet-grb-info 35987] GRB 241030B: Montarrenti Observatory optical upper limit
by GCN Circulars 31 Oct '24

31 Oct '24

TITLE: GCN CIRCULAR NUMBER: 38020 SUBJECT: GRB 241030B: Montarrenti Observatory optical upper limit DATE: 24/10/31 23:48:16 GMT FROM: Simone Leonini at Montarrenti Observatory (Siena, Italy) <s.leonini(a)iol.it> S. Leonini, M. Conti, P. Rosi, L.M. Tinjaca Ramirez (Montarrenti Observatory, Siena, Italy, part of UAI/SSV-GRB section), M.G. Dainotti (National Astronomical Observatory of Japan), Y. Niino (Tokyo University, Institute of Astronomy), K. Kalinowski (Aarhus University, Department of Physics and Astronomy) and B. De Simone (Universita' degli Studi Di Salerno) report: We performed follow-up observations of the field of GRB 241030B with the automated and remoted 0.53m Ritchey-Chretien telescope at Montarrenti Observatory (Siena, Italy, IAU code C88). Observations were started at 2024-10-30 21:55:28 UT, 3.33 hours after burst (Fermi-GBM team, GCN 37980; Swift trigger 1263840, GCN 37981 Klingler et al.; SVOM/ECLAIRs, GCN 37984 Zhao et al.) stacking 140x40s Rc-band CCD images. In our preliminary analysis, we have not found any optical transient candidate within the error-box (2.4 arcmin.) of the Neil Gehrels Swift Observatory enhanced position (RA 03h 23m 10.19s, Dec. +34d 26m 49.2s - J2000) down to the following 3-sigma optical upper limits: MJD Exp. Filter UL (3-sigma) 60614.4476 140x40s Rc > 20.91 Magnitude was calibrated with the nearby PanSTARRS stars converted using Lupton (2005) equations. No correction for galactic dust extinction was applied. Our observations are consistent with other fading detection and upper limits already reported (Fu et al., GCN 37985; Odeh et al., GCN 37986; Moskvitin et al., GCN 37987; Klotz et al., GCN 37989; Brivio et al., GCN 37991; Moskvitin et al., GCN 37995; Watson et al., GCN 37998; Qiu et al., GCN 37999; Hagio et al., GCN 38001; Tanvir et. al., GCN 38004; Strausbaugh et. al., GCN 38012; Swain et al., GCN 38013). View this GCN Circular online at https://gcn.nasa.gov/circulars/38020. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 35986] GRB 241030A / EP241030a: FTW Optical and NIR observations of the optical counterpart
by GCN Circulars 31 Oct '24

31 Oct '24

TITLE: GCN CIRCULAR NUMBER: 38019 SUBJECT: GRB 241030A / EP241030a: FTW Optical and NIR observations of the optical counterpart DATE: 24/10/31 22:50:07 GMT FROM: Malte Busmann at Ludwig-Maximilians-Universität München <m.busmann(a)physik.lmu.de> Malte Busmann (LMU), Daniel Gruen (LMU), Brendan O’Connor (Carnegie Mellon U.) and Antonella Palmese (Carnegie Mellon U.) report: We observed the optical counterpart of GRB 241030A (Fermi GBM team, GCN 37955; Klingler et al., GCN 37956; Watson et al., GCN 37957; Fernández-Rodríguez et al., GCN 37958; Zheng et al., GCN 37959, An et al., GCN 37960, Higuchi at al., GCN 3763; Qui et al., GCN 37965; Lin et al., GCN 37966 and similar) which was also detected as an X-ray transient by Swift (Klingler et al., GCN 37956) and Einstein Probe (Wu et al., GCN 37997) as EP241030a with the Three Channel Imager (3KK) at the Fraunhofer Telescope Wendelstein (FTW) in the r, i and J band simultaneously for 20 x 180 s starting at 2024-10-31T17:18:20 UT (1.48 days after the trigger). We detect the counterpart at r = (20.89 +/- 0.02) mag i = (20.62 +/- 0.02) mag J = (20.11 +/- 0.04) mag. The r and i band magnitudes are calibrated against the PanSTARRS1 catalog and provided in the AB system. The J band magnitude is calibrated against the 2MASS catalog and converted to the AB system with Blanton and Roweis, 2007, doi:10.1086/510127. Magnitudes are not corrected for Galactic extinction. We thank the staff of the Wendelstein Observatory for obtaining these observations. View this GCN Circular online at https://gcn.nasa.gov/circulars/38019. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 35985] EP241026b: Liverpool Telescope optical follow-up
by GCN Circulars 31 Oct '24

31 Oct '24

TITLE: GCN CIRCULAR NUMBER: 38018 SUBJECT: EP241026b: Liverpool Telescope optical follow-up DATE: 24/10/31 20:38:32 GMT FROM: A. Bochenek at Liverpool John Moores University <a.m.bochenek(a)2023.ljmu.ac.uk> A. Bochenek and D. A. Perley (LJMU) report: We observed the field of the fast X-ray transient EP241026b (Lian et al., GCN 37902) using the IO:O optical camera on the 2m robotic Liverpool Telescope. We obtained 6x200s exposures the SDSS r filter starting at 2024-10-31 01:41:20 UT, approximately 4.31 days after the trigger. The potential optical counterpart reported by Rossi et al. (GCN 37938) is marginally detected: forced photometry at the source location gives a 1.7-sigma detection, at a magnitude of r = 23.0 (-0.5, +0.9). More conservatively, a 2-sigma upper limit on the source magnitude is r > 22.1. Photometry was obtained using nearby PanSTARRS secondary standards and was not corrected for extinction. The transient has therefore faded since the observation by Rossi et al. (GCN 37938) - comparing their detection to our upper limit, it has faded by at least 0.6 mag between 1.48 and 4.31 days post-trigger. View this GCN Circular online at https://gcn.nasa.gov/circulars/38018. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 35984] Fermi trigger No 752083996: Global MASTER-Net observations report
by GCN Circulars 31 Oct '24

31 Oct '24

TITLE: GCN CIRCULAR NUMBER: 38017 SUBJECT: Fermi trigger No 752083996: Global MASTER-Net observations report DATE: 24/10/31 18:30:26 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 GRB241031.68 (trigger No 752083996,17h 36m 16.80s , -01d 51m 36.0s, R=10.07) errorbox 6170 sec after notice time and 6206 sec after trigger time at 2024-10-31 17:56:38 UT, with upper limit up to 17.1 mag. Observations started at twilight. The observations began at zenith distance = 71 deg. The sun altitude is -11.4 deg. The galactic latitude b = 15 deg., longitude l = 23 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2654939 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 6237 | 2024-10-31 17:56:38 | MASTER-SAAO | (17h 32m 32.69s , +01d 09m 33.5s) | C | 60 | 14.4 | 6316 | 2024-10-31 17:57:57 | MASTER-SAAO | (17h 27m 15.51s , -04d 31m 39.6s) | C | 60 | 13.8 | 6396 | 2024-10-31 17:59:17 | MASTER-SAAO | (17h 35m 19.75s , -04d 33m 11.5s) | C | 60 | 15.3 | 6475 | 2024-10-31 18:00:36 | MASTER-SAAO | (17h 42m 30.19s , -04d 34m 22.3s) | C | 60 | 15.0 | 6556 | 2024-10-31 18:01:57 | MASTER-SAAO | (17h 50m 26.74s , -04d 33m 36.1s) | C | 60 | 15.4 | 6635 | 2024-10-31 18:03:16 | MASTER-SAAO | (17h 39m 44.26s , +01d 09m 24.6s) | C | 60 | 14.2 | 6714 | 2024-10-31 18:04:35 | MASTER-SAAO | (17h 47m 34.54s , +01d 08m 10.6s) | C | 60 | 14.4 | 6794 | 2024-10-31 18:05:55 | MASTER-SAAO | (17h 30m 40.01s , -06d 26m 40.3s) | C | 60 | 15.3 | 6873 | 2024-10-31 18:07:14 | MASTER-SAAO | (17h 38m 32.30s , -06d 28m 10.4s) | C | 60 | 16.4 | 7032 | 2024-10-31 18:09:53 | MASTER-SAAO | (17h 34m 05.13s , +03d 02m 28.8s) | C | 60 | 12.5 | 7111 | 2024-10-31 18:11:13 | MASTER-SAAO | (17h 41m 10.08s , +03d 02m 53.0s) | C | 60 | 13.2 | 7191 | 2024-10-31 18:12:32 | MASTER-SAAO | (17h 49m 03.68s , +03d 03m 22.2s) | C | 60 | 13.8 | 7270 | 2024-10-31 18:13:51 | MASTER-SAAO | (17h 54m 32.80s , -00d 47m 01.2s) | C | 60 | 15.8 | 7350 | 2024-10-31 18:15:11 | MASTER-SAAO | (18h 02m 36.13s , -00d 47m 24.8s) | C | 60 | 16.4 | 7429 | 2024-10-31 18:16:30 | MASTER-SAAO | (17h 24m 40.53s , -00d 42m 55.0s) | C | 60 | 16.4 | 7508 | 2024-10-31 18:17:50 | MASTER-SAAO | (17h 32m 33.05s , -00d 45m 13.5s) | C | 60 | 16.8 | 7588 | 2024-10-31 18:19:09 | MASTER-SAAO | (17h 25m 37.59s , -02d 36m 55.7s) | C | 60 | 16.1 | 7667 | 2024-10-31 18:20:28 | MASTER-SAAO | (17h 33m 24.99s , -02d 38m 19.5s) | C | 60 | 16.6 | 7747 | 2024-10-31 18:21:48 | MASTER-SAAO | (17h 39m 39.44s , -00d 43m 41.3s) | C | 60 | 16.6 | 7826 | 2024-10-31 18:23:07 | MASTER-SAAO | (17h 47m 38.56s , -00d 45m 12.4s) | C | 60 | 16.9 | 7905 | 2024-10-31 18:24:26 | MASTER-SAAO | (17h 40m 34.97s , -02d 39m 41.4s) | C | 60 | 17.1 | 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/38017. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 35983] GRB 241030A: SAO RAS optical observations
by GCN Circulars 31 Oct '24

31 Oct '24

TITLE: GCN CIRCULAR NUMBER: 38016 SUBJECT: GRB 241030A: SAO RAS optical observations DATE: 24/10/31 17:15:46 GMT FROM: Moskvitin Alexander at SAO RAS <mosk(a)sao.ru> A. S. Moskvitin (SAO RAS) and V. P. Goranskij (SAI MSU) report on behalf of the GRB follow-up team. We observed the field of the GRB 241030A (Klingler et al., GCN 37956; Beardmore et al., GCN 37962; Wang et al., GCN 37972; Pillera et al., GCN 37979; Ridnaia et al., GCN 37982; Ambrosi et al., GCN 37988; Wu et al., GCN 37997) with the 1-m telescope of SAO RAS, Zeiss-1000 equipped with the CCD-photometer on October 30/31 night. We obtained series of 300 and 600 sec. images in Rc band. The OT (Klingler et al., GCN 37956; Watson et al., GCN 37957; Fernández-Rodríguez et al., GCN 37958; Zheng et al., GCN 37959; An et al., GCN 37960; Higuchi et al., GCN 37963; Qiu et al., GCN 37965; Lin et al., GCN 37966; Wu et al., GCN 37970; Breeveld & Klingler, GCN 37974; Méndez-Lapido et al., GCN 37993) is clearly detected in our stacked frames. Preliminary photometry calibrated against nearby Pan-STARRS stars (magnitudes converted with Lupton 2005 equations) and not corrected by MW extinction: date UT_start--UT_end t_mid-T0, h exp., s R_mag Oct. 30 17:21:38--17:26:38 11.8392 6 x 300 18.72 +/- 0.04 Oct. 30 20:40:51--21:44:59 15.4145 6 x 600 19.09 +/- 0.06 Oct. 30/31 23:18:20--02:14:51 18.9756 15 x 600 19.36 +/- 0.04 list of used Pan-STARRS stars: R.A. (J2000) Decl. (J2000) R_mag (Lupton 2005) 343.156212740 80.434129340 14.119 343.189894620 80.452656920 17.502 343.155709870 80.466614280 16.501 343.372455850 80.465046470 14.448 View this GCN Circular online at https://gcn.nasa.gov/circulars/38016. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 35982] GRB 241030A: SAO RAS optical observations
by GCN Circulars 31 Oct '24

31 Oct '24

TITLE: GCN CIRCULAR NUMBER: 38016 SUBJECT: GRB 241030A: SAO RAS optical observations DATE: 24/10/31 17:15:46 GMT FROM: Moskvitin Alexander at SAO RAS <mosk(a)sao.ru> A. S. Moskvitin (SAO RAS) and V. P. Goranskij (SAI MSU) report on behalf of the GRB follow-up team. We observed the field of the GRB 241030A (Klingler et al., GCN 37956; Beardmore et al., GCN 37962; Wang et al., GCN 37972; Pillera et al., GCN 37979; Ridnaia et al., GCN 37982; Ambrosi et al., GCN 37988; Wu et al., GCN 37997) with the 1-m telescope of SAO RAS, Zeiss-1000 equipped with the CCD-photometer on October 30/31 night. We obtained series of 300 and 600 sec. images in Rc band. The OT (Klingler et al., GCN 37956; Watson et al., GCN 37957; Fernández-Rodríguez et al., GCN 37958; Zheng et al., GCN 37959; An et al., GCN 37960; Higuchi et al., GCN 37963; Qiu et al., GCN 37965; Lin et al., GCN 37966; Wu et al., GCN 37970; Breeveld & Klingler, GCN 37974; Méndez-Lapido et al., GCN 37993) is clearly detected in our stacked frames. Preliminary photometry calibrated against nearby Pan-STARRS stars (magnitudes converted with Lupton 2005 equations) and not corrected by MW extinction: date UT_start--UT_end t_mid-T0, h exp., s R_mag Oct. 30 17:21:38--17:26:38 11.8392 6 x 300 18.72 +/- 0.04 Oct. 30 20:40:51--21:44:59 15.4145 6 x 600 19.09 +/- 0.06 Oct. 30/31 23:18:20--02:14:51 18.9756 15 x 600 19.36 +/- 0.04 list of used Pan-STARRS stars: R.A. (J2000) Decl. (J2000) R_mag (Lupton 2005) 343.156212740 80.434129340 14.119 343.189894620 80.452656920 17.502 343.155709870 80.466614280 16.501 343.372455850 80.465046470 14.448 View this GCN Circular online at https://gcn.nasa.gov/circulars/38016. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 35981] GRB 241030A: Fermi GBM Observation
by GCN Circulars 31 Oct '24

31 Oct '24

TITLE: GCN CIRCULAR NUMBER: 38015 SUBJECT: GRB 241030A: Fermi GBM Observation DATE: 24/10/31 15:13:27 GMT FROM: Cuán de Barra at UCD <cuan.debarra(a)ucdconnect.ie> C. de Barra (UCD) and C. Meegan (UAH) report on behalf of the Fermi Gamma-ray Burst Monitor Team: "At 05:48:03.33 UT on 30 October 2024, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB241030A (trigger 751960088/241030242). which was also detected by Swift-BAT (Klingler et al. 2024, GCN 37956), SVOM-GRM (Wang et al. 2024, GCN 37972), and Konus-Wind (Ridnaia et al. 2024, GCN 37982) The Fermi GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight is 17 degrees. The GBM light curve consists of multiple emission episodes with a duration (T90) of about 166 s (50-300 keV). The time-averaged spectrum from T0-21 to T0+217 s is best fit by a Band function with Epeak = 129 +/- 7 keV, alpha = -1.35 +/- 0.02, and beta = -2.31 +/- 0.08. The event fluence (10-1000 keV) in this time interval is (6.235 +/- 0.095)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+147 s in the 10-1000 keV band is 20 +/- 0.4 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog: https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html For Fermi GBM data and info, please visit the official Fermi GBM Support Page: https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/" View this GCN Circular online at https://gcn.nasa.gov/circulars/38015. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 35980] EP241021a: AMI-LA radio detection
by GCN Circulars 31 Oct '24

31 Oct '24

TITLE: GCN CIRCULAR NUMBER: 38014 SUBJECT: EP241021a: AMI-LA radio detection DATE: 24/10/31 15:13:01 GMT FROM: Francesco Carotenuto at University of Oxford <francesco.carotenuto(a)physics.ox.ac.uk> F. Carotenuto (INAF/OAR), J. Bright (Oxford), R. Fender (Oxford) After the first radio detection with ATCA (Ricci et al. GCN 37949), we observed the Fast X-ray Transient EP241021a (Hu et al. GCN 37834; Fu et al. GCN 37840, Wang et al. GCN 37848) with the Arcminute MicroKelvin Imager - Large Array for a total of 4.7 hours starting on 30 October 2024 at 20:59:50.7 UTC. 3C286 and J0149+0555 were used as flux and time dependent complex gain calibrators, respectively. We obtained a significant detection of the target with a flux density of ~450 uJy/beam at a central frequency of 15.5 GHz. The rms noise in the field is ~75 uJy/beam. Further AMI-LA observations are planned. We thank the Mullard Radio Astronomy Observatory staff for operating and maintaining the AMI-LA. View this GCN Circular online at https://gcn.nasa.gov/circulars/38014. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 35979] GRB 241030B : GIT optical upper limits
by GCN Circulars 31 Oct '24

31 Oct '24

TITLE: GCN CIRCULAR NUMBER: 38013 SUBJECT: GRB 241030B : GIT optical upper limits DATE: 24/10/31 14:28:02 GMT FROM: V. Swain at IIT Bombay <vishwajeet.s(a)iitb.ac.in> V. Swain, A.P. Saikia, T. Mohan, R. Kumar, V. Bhalerao (IITB), G.C. Anupama, S. Barway (IIA) and K. Angail (IAO) report on behalf of the GIT team: We observed the field of GRB 241030B (Fermi GBM Team, GCN 37980, Klingler et al. GCN 37981) with 0.7m GROWTH-India Telescope (GIT) in g', r', and i' filters. We started the observation at 2024-10-30 18:42:39 UT, i.e., 8.3 mins after the Fermi GBM trigger. We took multiple exposures and obtained upper limits at the position reported by Fu et. al., (GCN 37985). The photometry results follow as: ------------------------------------------------------------------------------ | JD (mid) | t-t0 (mins) | Filter | Exposure (s) | Upper limit (AB) | | ----------------- | ----------- |------- | ------------ | -------------- | | 2460614.279618055 | 8.32 | r' | 20 | 18.9 | | 2460614.281053241 | 10.38 | g' | 20 | 18.7 | | 2460614.282048611 | 11.82 | i' | 30 | 18.0 | | 2460614.434398148 | 231.2 | g' | 440 | 21.2 | | 2460614.439745370 | 238.9 | r' | 440 | 21.3 | | 2460614.445185185 | 246.7 | i' | 400 | 20.2 | ------------------------------------------------------------------------------ Our results are consistent with Fu et al.; (GCN 37985), Odeh et al.; (GCN 37986), Moskvitin et al.; (GCN 37987), Brivio et al.; (GCN 37991), Moskvitin et al.; (GCN 37995), Watson et al.; (GCN 37998), Qiu et al.; (GCN 37999), Hagio et al.; (GCN 38001), Tanvir et. al.; (GCN 38004), Breeveld et. al.; (GCN 38008), Strausbaugh et. al.; (GCN 38012). The measurement is calibrated against PanSTARRS DR1 (Chambers et al., 2016) and not corrected for Galactic extinction. The GROWTH India Telescope (GIT; Kumar et al. 2022) is a 70-cm telescope with a 0.7-degree field of view, set up by the Indian Institute of Astrophysics (IIA) and the Indian Institute of Technology Bombay (IITB) with funding from DST-SERB and IUSSTF. It is located at the Indian Astronomical Observatory (Hanle), operated by IIA. We acknowledge funding by the IITB alumni batch of 1994, which partially supports the operations of the telescope. Telescope technical details are available at https://sites.google.com/view/growthindia/. View this GCN Circular online at https://gcn.nasa.gov/circulars/38013. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 35978] GRB 241030B: LCOGT Optical Upper Limits
by GCN Circulars 31 Oct '24

31 Oct '24

TITLE: GCN CIRCULAR NUMBER: 38012 SUBJECT: GRB 241030B: LCOGT Optical Upper Limits DATE: 24/10/31 14:09:14 GMT FROM: Robert Strausbaugh at Eastern Illinois University <rstrausbaugh(a)eiu.edu> R. Strausbaugh (Eastern Illinois University), A. Cucchiara (NASA) report on behalf of a larger collaboration: We observed the Fermi/Swift GRB 241030B field (Fermi GBM Team, GCN 37980; Klingler et al., GCN 37981) with the LCOGT 1-meter Sinistro instrument at the Teide Observatory, Tenerife site, on October 30, from 21:50 to 22:22 UT (corresponding to 3.27 to 3.8 hours after the GRB trigger time) with the sdss r and i filters. We performed a series of 3x300s exposures in i- and r-bands. We do not detect a source within the enhanced Swfit XRT error region (Evans et al., GCN 37983) in either band. This result is consistent with fading from early optical detections (Fu et al., GCN 37985; Odeh et al, GCN 37986; Moskvitin et al., GCN 37987, Brivio et al., GCN 37991; Moskvitin et al., GCN 37995; Qiu et al., GCN 37999; Tanvir et al., GCN 38004; Breeveld et al., GCN 38008) and other optical upper limits (Klotz et al., GCN 37989; Hagio et al., GCN 38001). The following 5-sigma upper limits are calculated using the PanSTARRS catalog as reference: r > 22.5 i > 22.0 These magnitudes are not corrected for galactic extinction. View this GCN Circular online at https://gcn.nasa.gov/circulars/38012. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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