July 2026 - vsnet-grb-info - ooruri.kusastro.kyoto-u.ac.jp

[vsnet-grb-info 43321] EP260707a: Einstein Probe detection of an X-ray transient
by GCN Circulars 07 Jul '26

07 Jul '26

TITLE: GCN CIRCULAR NUMBER: 45107 SUBJECT: EP260707a: Einstein Probe detection of an X-ray transient DATE: 26/07/07 18:30:09 GMT FROM: EP Team at NAOC/CAS <ep_ta(a)bao.ac.cn> H. Zhou, Y. F. Liang (PMO), K. R. Ni (CCNU), C.-K. Kan (HKU), H. Sun (NAO, CAS) on behalf of the Einstein Probe (EP) team: We report on the detection of an X-ray transient by the Wide-field X-ray Telescope (WXT) on board the Einstein Probe (EP) mission, designated EP260707a. The transient triggered EP-WXT (ID: 01709274241) at 2026-07-07T16:45:24 (UTC). The WXT position of the source is R.A. = 306.233 deg, DEC = -26.589 deg (J2000) with an uncertainty of 3 arcmin in radius (90% C.L. statistical and systematic). A follow-up observation with the Follow-up X-ray Telescope (FXT) was performed automatically. Within the WXT error circle, an uncatalogued X-ray source was detected at R.A. = 306.1900 deg, DEC = -26.5853 deg (J2000) with an uncertainty of 20 arcsec in radius (90% C.L. statistical and systematic). Further information will be updated when the telemetry data is received. Launched on January 9, 2024, EP is a space X-ray observatory to monitor the soft X-ray sky with X-ray follow-up capability (Yuan et al. 2022, Handbook of X-ray and Gamma-ray Astrophysics). View this GCN Circular online at https://gcn.nasa.gov/circulars/45107. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 43320] Nova AT2026oyp (ASASSN-26dt): Pre-outburst Swift UVOT observation
by GCN Circulars 07 Jul '26

07 Jul '26

TITLE: GCN CIRCULAR NUMBER: 45106 SUBJECT: Nova AT2026oyp (ASASSN-26dt): Pre-outburst Swift UVOT observation DATE: 26/07/07 17:06:06 GMT FROM: Paul Kuin at MSSL <npkuin(a)gmail.com> The LMC nova AT2026oyp (ASASSN-26dt) was observed by Swift UVOT in the UVW1 filter on 2017-11-14 in a 54. s exposure. That predated the eruption reported in ATEL #17878 (Chomiuk et al.) and the nova was reported to have peaked at g=10.5 mag on 2026 June 11. The quescent magnitude in the UVOT UVW1 filter was UVW1 = 19.56 +/- 0.26 (stat) +/- 0.03 (sys) (AB) mag consistent with the other reported quiescent values, at a position RA = 00h 50m 45.11s, Dec = -71d 38m 38.51s (J2000) with uncertainty = +/- 1.05" (90% confidence) marginally consistent with the reported position at RA=01:50:45.142, Dec= -71:38:36.96. View this GCN Circular online at https://gcn.nasa.gov/circulars/45106. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 43319] GRB 260705A: Candidate Optical Counterpart from SOAR and Gemini-South and Possible Association with GRB 260705B
by GCN Circulars 07 Jul '26

07 Jul '26

TITLE: GCN CIRCULAR NUMBER: 45105 SUBJECT: GRB 260705A: Candidate Optical Counterpart from SOAR and Gemini-South and Possible Association with GRB 260705B DATE: 26/07/07 15:52:15 GMT FROM: James Freeburn at University of North Carolina at Chapel Hill <jamesfreeburn54(a)gmail.com> James Freeburn (UNC), Tomás Ahumada (NOIRLab), Jillian Rastinejad (UMD), Gokul Srinivasaragavan (UMD/Northwestern), Huei Sears (Rutgers), Anirudh Salgundi (UNC), report on behalf of a larger collaboration: We observed the field of GRB 260705A (SVOM burst-id sb26070502) detected by SVOM (Saccardi et al., GCN 45079) and Fermi (Hamburg et al., GCN 45080) using the SOAR and Gemini-South telescopes. We obtained 8 x 300 s of i-band imaging with SOAR using the Goodman High Throughput Spectrograph (SOAR2026A-018; PI: Andreoni) in imaging mode with the Red camera at a mid-time of 2026-07-07 10:19 UT, corresponding to ~45 hrs after the trigger. We performed SOAR data reduction with a custom pipeline using pre-reduced images from the Goodman pipeline (Torres et al. 2018). We obtained 4 x 120 s of r-band imaging at three different pointings using GMOS on Gemini-South (PI: Srinivasaragavan) at a mid-time of 2026-07-07 09:35 UT and performed image reduction with DRAGONS (Labrie et al. 2019). For both images, we performed image subtraction using SFFT (Hu et al. 2022) against DECam Legacy Survey images. The GMOS image covers ~77% of the SVOM localization (Saccardi et al., GCN 45079), while the resampled Goodman image covers ~65% of the localization. We detect a candidate optical counterpart at: R.A. (J2000) = 03:53:12.49 (58.30204 d) +/- 0.5’’ Dec. (J2000) = -31:39:08.61 (-31.65239 d) +/- 0.5’’ with AB magnitudes, calibrated with SkyMapper DR4 (Onken et al., 2024), of: r = 21.48 +/- 0.08 i = 21.44 +/- 0.04 These magnitudes have not been corrected for Galactic extinction of A_V = 0.028 mag. The brightness of this source is consistent with the upper limits found by LCO (Shi et al., GCN 45084), though these observations were taken ~30 hours prior. This candidate optical counterpart is embedded in a catalogued source, WISEA J035312.50-313908. WISEA J035312.50-313908.7 has no reported proper motion in Gaia DR3 (Gaia Collaboration 2022) and is classified as a ‘high-confidence galaxy’ in DES DR2 (Abbott et al. 2021), therefore we conclude the source is a galaxy. WISEA J035312.50-313908.7 has a photometric redshift of z = 0.178 +/- 0.009 from Legacy Survey DR10 (Duncan et al. 2022). The candidate optical counterpart is consistent with a nuclear origin with an offset of ~0.4” from the host center. We disfavor this counterpart as an AGN given the WISE color of W1-W2 = -0.05 (Cutri et al. 2013) and the absence of an AGN match in the Milliquas catalog (Flesch et al. 2023). We note that GRB 260705B, detected by Fermi (GCN 45081), has a localization consistent with GRB 260705A and was detected ~ 11 hr (~ 40,000 s) after. If these bursts are connected to the same source, this suggests a possible identification as an ultra-long GRB. The extended gamma-ray duration and nuclear location are also reminiscent of jetted TDEs (e.g., Swift J1644+57, Bloom et al. 2011; Swift J2058+05, Cenko et al. 2012; Swift J1112-82, Brown et al. 2015). Further observations are planned to assess the variability of this source. We thank the staff at Gemini-South and SOAR for their assistance with the observations. View this GCN Circular online at https://gcn.nasa.gov/circulars/45105. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 43318] GRB 260705C: Glowbug gamma-ray detection of a short burst
by GCN Circulars 07 Jul '26

07 Jul '26

TITLE: GCN CIRCULAR NUMBER: 45104 SUBJECT: GRB 260705C: Glowbug gamma-ray detection of a short burst DATE: 26/07/07 15:25:19 GMT FROM: C.C. Cheung at Naval Research Lab <Teddy.Cheung(a)nrl.navy.mil> C.C. Cheung, R. Woolf, M. Kerr, J.E. Grove (NRL), A. Goldstein (USRA), C.A. Wilson-Hodge, D. Kocevski (MSFC), and M.S. Briggs (UAH) report: The Glowbug gamma-ray telescope [1,2,3], operating on the International Space Station, reports the detection of GRB 260705C, which was also detected by Fermi/GBM (GCN 45082). Using an adaptive window with a resolution of 32-ms, the burst onset is determined to be 2026-07-05 13:58:57.840 with a duration of 0.26 s and a total significance of about 19.5 sigma. The light curve comprises a single peak. The analysis results presented here are preliminary and use a response function that lacks a detailed characterization of the surrounding passive structure of the ISS. Glowbug is a NASA-funded technology demonstrator for sensitive, low-cost gamma-ray transient telescopes developed, built, and operated by the U.S. Naval Research Laboratory (NRL) with support from the University of Alabama in Huntsville, USRA, and NASA MSFC. It was launched on 2023 March 15 aboard the Department of Defense Space Test Program’s STP-H9 to the ISS and operated until 2024 April when it was put in safe storage on orbit. Glowbug was removed from storage and resumed operation on 2025 September 12. [1] Grove, J.E. et al. 2020, Proc. Yamada Conf. LXXI, arXiv:2009.11959 [2] Woolf, R.S. et al. 2022, Proc. SPIE, 12181, id. 121811O [3] Woolf, R.S. et al. 2024, Proc. SPIE, 13151, id. 1315108 Distribution Statement A: Approved for public release. Distribution is unlimited. View this GCN Circular online at https://gcn.nasa.gov/circulars/45104. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 43317] GRB 260706A: SVOM/ECLAIRs refined analysis
by GCN Circulars 07 Jul '26

07 Jul '26

TITLE: GCN CIRCULAR NUMBER: 45103 SUBJECT: GRB 260706A: SVOM/ECLAIRs refined analysis DATE: 26/07/07 15:08:36 GMT FROM: SVOM_group <svomgroup(a)bao.ac.cn> Authors: S. Guillot, M. Brunet, J. Alaux (IRAP), F. Daigne, M. Pillas (IAP), report on behalf of the SVOM/ECLAIRs team: Using the event-by-event data downloaded through the X-band ground station, we report further analysis of SVOM/ECLAIRs observations of GRB 260706A (SVOM Burst id sb26070606, GCN #45089) with trigger time T0 = 2026-07-06T16:12:23 UTC, which was also detected by Fermi/GBM (GCN #45088). The burst that triggered ECLAIRs onboard shows a multiple peak lightcurve, and the burst duration is T90 = 23.41 +0.64/-0.89 s in the 4-120 keV energy band. The time-averaged spectrum from T0 to T0+24 s in the 5-120 keV energy range is best fitted by a cut-off powerlaw model with alpha = -1.4 +/- 0.1 and Epeak = 38.1 +/- 6.4 keV. With this model, the 4-120 keV fluence is (3.5 +/- 0.3)e-6 erg/cm^2 and the 4-120 keV photon flux is 5.9 +/- 0.3 ph/cm^2/s. All the quoted errors are at the 68% confidence level. The Space-based multi-band astronomical Variable Objects Monitor (SVOM) is a China-France joint mission led by the Chinese National Space Administration (CNSA), French Space Agency (CNES), and the Chinese Academy of Sciences (CAS), which is dedicated to observing gamma-ray bursts and other transient phenomena in the energetic universe. ECLAIRs was developed jointly by CNES, CEA-IRFU, CNRS-IRAP, CNRS-APC. The SVOM/ECLAIRs point of contact for this burst is: Sebastien Guillot (IRAP) (sebastien.guillot at utoulouse.fr) View this GCN Circular online at https://gcn.nasa.gov/circulars/45103. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 43316] GRB 260704A: SVOM/COLIBRÍ (FM-GFT) possible optical counterpart candidate
by GCN Circulars 07 Jul '26

07 Jul '26

TITLE: GCN CIRCULAR NUMBER: 45102 SUBJECT: GRB 260704A: SVOM/COLIBRÍ (FM-GFT) possible optical counterpart candidate DATE: 26/07/07 13:16:54 GMT FROM: F. Magnani at Aix-Marseille Université, CPPM/CNRS <francesco.magnani.work(a)gmail.com> GRB 260704A: SVOM/COLIBRÍ (FM-GFT) possible optical counterpart candidate Noémie Globus (UNAM), Francesco Magnani (CPPM), Camila Angulo (UNAM), Jean-Grégoire Ducoin (CPPM), Nathaniel R. Butler (ASU), Stéphane Basa (UAR Pytheas), Jean-Luc Atteia (IRAP), William H. Lee (UNAM), Edilberto Aguilar-Ruiz (UNAM), Dalya Akl (NYUAD), Sarah Antier (IJCLAB), Rosa L. Becerra (UNAM), Damien Dornic (CPPM), Francis Fortin (IRAP), Leonardo García-García (UNAM), Ramandeep Gill (UNAM), Marion Guelfand (CPPM), Asuka Kuwata (UNAM), Massimiliano Lincetto (CPPM), Nikos Mandarakas (LAM), Diego López-Cámara (UNAM), Enrique Moreno Méndez (UNAM), Margarita Pereyra (UNAM), Fredd Sánchez Álvarez (UNAM), Benjamin Schneider (LAM), Antonio de Ugarte Postigo (LAM), Alan M. Watson (UNAM), W.J Xie (NAOC), Y. H. Cheng (YNU), C. Plasse (HKU), report: We imaged the field of the SVOM GRB 260704A (W.J Xie et al., GCN Circ. 45072) using the DDRAGO two-channel wide-field imager on the SVOM/COLIBRÍ (FM-GFT) telescope. We observed from 2026-07-05 07:25:02 to 11:20:12 UTC (from 27.7 to 31.7 hours after the trigger) and obtained 104 minutes of simultaneous exposure in the r and z filters. The data were reduced, coadded, and analyzed with the ASU pipeline. The photometry was calibrated using nearby stars from the PanSTARRS DR1 catalog, is in the AB system, and is not corrected for Galactic extinction. We tentatively detected a faint, uncatalogued source consistent with both the SVOM/MXT error circle (W.J. Xie et al., GCN Circ. 45072) and the EP/FXT error circle (Y.-H. I. Yin et al., GCN Circ. 45078) at: RA (J2000) = 21:14:51.52 = 318.71468 deg, Dec (J2000) = -25:30:29.4 = -25.50816 deg, with an estimated astrometric uncertainty of 0.5 arcsec. The preliminary unsubtracted magnitude derived for that source was: r = 23.54 ± 0.22 z = 22.70 ± 0.27 We reobserved from 2026-07-06 07:18:26 to 09:47:39 UTC (from 51.62 to 54.11 hours after the trigger) and obtained 111 minutes of simultaneous exposure in the r and z filters. Compared to our previous observations, the source has faded. The preliminary unsubtracted magnitude is: r = 24.08 ± 0.23 mag, z = 23.19 ± 0.28 mag. The detection of the source in two independent optical bands, together with its fading between the two observing epochs, makes it a possible candidate for the optical counterpart of the GRB. We thank the staff of the Observatorio Astronómico Nacional at Sierra de San Pedro Mártir, as well as the technical and engineering teams at CEA, CPPM, IRAP, LAM, OHP, OSU Pytheas, and UNAM. COLIBRÍ is an astronomical observatory developed and operated jointly by France (AMU, CNES and CNRS) and Mexico (UNAM and SECIHTI). It is located at the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir, Baja California, Mexico. View this GCN Circular online at https://gcn.nasa.gov/circulars/45102. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 43315] GRB 260706A: SVOM/GRM observation
by GCN Circulars 07 Jul '26

07 Jul '26

TITLE: GCN CIRCULAR NUMBER: 45101 SUBJECT: GRB 260706A: SVOM/GRM observation DATE: 26/07/07 12:40:33 GMT FROM: Yue Wang <m18509381757(a)163.com> SVOM/GRM team: Yue Wang, Chen-Wei Wang, Shi-Jie Zheng, Yue Huang, Shao-Lin Xiong, Shuang-Nan Zhang (IHEP) SVOM/ECLAIRs team: Sebastien Guillot (IRAP) Report on behalf of the SVOM team: SVOM/GRM was triggered in-flight by GRB 260706A at 2026-07-06T16:12:22.000 (T0), which is also detected by SVOM/ECLAIRs (J. Alaux et. al., GCN #45089) and Fermi/GBM (Fermi GBM team, GCN #45088, #45093). With the event-by-event data downloaded through the X-band ground station, the GRM light curve shows that this burst consists of multiple peaks with a T90 of 31 +12/-8 s in the 15-5000 keV band. The SVOM/GRM light curve can be found here: https://www.bursthub.cn//admin/static/svgrb260706A.png In addition, the position of this burst, as determined by SVOM/ECLAIRs (RA = 33.8323 deg, Dec = -49.1375 deg, Error = 3.17 arcmin, GCN #45089), is used for the spectral analysis. With this localization, the time-averaged spectrum from T0-3.0 to T0+30.0 s is best fitted by a power law function with an exponential high-energy cutoff. The power law index is -1.47 +0.16/-0.15 and the cutoff energy, parameterized as Epeak, is 53.98 +5.09/-4.96 keV. The event fluence (10-1000 keV) in this time interval is (3.96 +0.21/-0.19)E-06 erg/cm^2. The localization of GRB 260706A in the 'Amati' relation diagram is shown at: https://www.bursthub.cn//admin/static/svgrb260706A_amati.png The localization of GRB 260706A in the 'Yonetoku' relation diagram is shown at: https://www.bursthub.cn//admin/static/svgrb260706A_yonetoku.png The Space Variable Objects Monitor (SVOM) is a China-France joint mission led by the Chinese National Space Administration (CNSA, China), National Center for Space Studies (CNES, France) and the Chinese Academy of Sciences (CAS, China), which is dedicated to observing gamma-ray bursts and other transient phenomena in the energetic universe. GRM is developed by the Institute of High Energy Physics (IHEP) of CAS. The SVOM/GRM point of contact for this burst is: Yue Wang (IHEP) (yuewang(a)ihep.ac.cn) View this GCN Circular online at https://gcn.nasa.gov/circulars/45101. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 43314] GRB 260706A: REM optical/NIR observations
by GCN Circulars 07 Jul '26

07 Jul '26

TITLE: GCN CIRCULAR NUMBER: 45100 SUBJECT: GRB 260706A: REM optical/NIR observations DATE: 26/07/07 12:14:45 GMT FROM: Riccardo Brivio at INAF-OAB <riccardo.brivio(a)inaf.it> R. Brivio, M. Ferro, P. D'Avanzo, S. Covino, D. Fugazza (INAF-OAB) report on behalf of the REM team: We observed the field of GRB 260706A, detected by SVOM/ECLAIRs (Alaux et al., GCN 45089) and Fermi/GBM (Trigg et al., GCN 45093) with the REM 60 cm robotic telescope located at the ESO observatory of La Silla (Chile). The observations were carried out in the g,r,i,z, and K bands, started on 2026-07-07 at 04:49:10 UT (i.e. 12.6 hr after the burst) and lasted for about 1 hr. From preliminary photometry, we do not detect any uncatalogued source within the EP/FXT error box (Liang et al., GCN 45097) down to the following 3sigma limits: r > 19.4 (AB; calibrated against the SkyMapper catalogue), at a mid-time of 13.5 hr after the trigger; K > 13.6 (Vega; calibrated against the 2MASS catalogue), at a mid-time of 13.3 hr after the trigger. View this GCN Circular online at https://gcn.nasa.gov/circulars/45100. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 43313] IceCube-260704A: No candidates from the Zwicky Transient Facility
by GCN Circulars 07 Jul '26

07 Jul '26

TITLE: GCN CIRCULAR NUMBER: 45099 SUBJECT: IceCube-260704A: No candidates from the Zwicky Transient Facility DATE: 26/07/07 10:32:00 GMT FROM: Robert David Stein at JSI <rdstein(a)umd.edu> Akshay Eranhalodi (DESY), Robert Stein (JSI), Cristobal Zilleruelo Cañas (DESY), Jannis Necker (Leiden University), and Anna Franckowiak (Ruhr University Bochum) report, On behalf of the Zwicky Transient Facility (ZTF) and Global Relay of Observatories Watching Transients Happen (GROWTH) collaborations: As part of the ZTF neutrino follow up program (Stein et al. 2023), we observed the localization region of the neutrino event IceCube-260704A (Zegarelli et. al, GCN 45075) with the Palomar 48-inch telescope, equipped with the 47 square degree ZTF camera (Bellm et al. 2019, Graham et al. 2019). We started observations in the g- and r-band beginning at 2026-07-04 07:25 UTC, approximately 0.1 hours after event time. We covered 98.4% (0.8 sq deg) of the reported localization region. This estimate accounts for chip gaps. Each exposure was 300s with a typical depth of 21.0 mag. The images were processed in real-time through the ZTF reduction and image subtraction pipelines at IPAC to search for potential counterparts (Masci et al. 2019). AMPEL (Nordin et al. 2019, Stein et al. 2021) was used to search the alerts database for candidates. We reject stellar sources (Tachibana and Miller 2018) and moving objects, and apply machine learning algorithms (Mahabal et al. 2019). We are left with the following high-significance transient candidate by our pipeline, lying within the 90.0% localization of the skymap: +--------------------------------------------------------------------------------+ | ZTF Name | IAU Name | RA (deg) | DEC (deg) | Filter | Mag | MagErr | +--------------------------------------------------------------------------------+ | ZTF19ablafcb | ------- | 320.5248614 | +34.5149697 | g | 21.09 | 0.20 | +--------------------------------------------------------------------------------+ ZTF19ablafcb was first detected by ZTF on 2019-07-31. It is located at a galactic latitude of -10.94 degrees. Based on its WISE colours (W1-W2=0.6), historical optical variability in ZTF data, and nuclear location, it is likely that the source is an AGN. The source is clearly visible in archival PS1 imaging, and the source does not appear to be significantly flaring relative to this baseline. We therefore find no temporal evidence to suggest that the AGN is associated to the high-energy neutrino. We do not select the AGN WISEA J212302.62+340634.2, which was observed by Adami et al. (GCN 45085). This is expected, given that the source was reported to not be flaring. Our ZTF ToO program only targets AGN which are undergoing flares coincident with the detection of neutrinos. ZTF and GROWTH are worldwide collaborations comprising Caltech/IPAC, USA; University of Maryland, USA; University of California, Berkeley, USA; Cornell University, USA; Drexel University, USA; University of North Carolina at Chapel Hill, USA; Institute of Science and Technology, Austria; National Central University, Taiwan; OKC, Sweden; DZA, Germany. GROWTH acknowledges generous support of the NSF under PIRE Grant No 1545949. Alert distribution service provided by DIRAC@UW (Patterson et al. 2019). Alert database searches are done by AMPEL (Nordin et al. 2019). Alert filtering is performed with the nuztf (Stein et al. 2021, https://github.com/desy-multimessenger/nuztf) View this GCN Circular online at https://gcn.nasa.gov/circulars/45099. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 43312] GRB 260706A: LCO optical upper limit
by GCN Circulars 07 Jul '26

07 Jul '26

TITLE: GCN CIRCULAR NUMBER: 45098 SUBJECT: GRB 260706A: LCO optical upper limit DATE: 26/07/07 09:30:30 GMT FROM: SVOM_group <svomgroup(a)bao.ac.cn> A. Saccardi (CEA/Irfu), D. Turpin (CEA/Irfu), F. Daigne, M. Pillas (IAP), report on behalf of the SVOM mission team: We observed the field of GRB 260706A detected by SVOM/ECLAIRs (Alaux et al., GCN 45089) and Fermi/GBM (Fermi GBM team, GCN 45088; Trigg et al., GCN 45093), with the LCO 1m telescope at Cerro Tololo Observatory equipped with the Sinistro instrument. Our observation started on 2026-07-07 at 08:15:35 UT (about 16 hr after the trigger) and we obtained 3x200 s exposures in the SDSS r filter. In the stacked image, we do not detect any new source within the EP/FXT error box (Liang et al., GCN 45097). We measure the following upper limit calibrated against the SkyMapper DR4 catalog, and not corrected for Galactic extinction: r > 22.3 AB (3-sigma, mid-time 16.14 hr after the trigger). This project is funded by the SVOM collaboration. View this GCN Circular online at https://gcn.nasa.gov/circulars/45098. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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