TITLE: GCN CIRCULAR NUMBER: 32939 SUBJECT: GRB 221110A: GRANDMA observations DATE: 22/11/15 13:57:43 GMT FROM: Iara Tosta e Melo at INFN Content: M. Coughlin (UMN), E. Gurbanov (ShAO), F. Navarete (SOAR/NOIRLab), N. Kochiashvili (AbAO), M. Masek (FZU), Y. Rajabov (UBAI), T. Sadibekova (AIM-CEA), M. Freeberg (KNC), A. Klotz (OMP/IRAP), M. Boer, A. de Ugarte Postigo, S. Antier (OCA/Artemis), D. Turpin (CEA), R.W. Kiendrebeogo (OCA/Artemis, LPCE/UJKZ), I. Tosta e Melo (INFN-LNS), M. Lamoureux, K. Kruiswijk (UCLouvain), J.-G. Ducoin (IAP), C. Rinner, Z. Benkhaldoun (OUCA), J. Ali, A. Kaouech (OUCA/KNC), A. M. Fouad, A. Takey, A. Hamed, M. Abdel-Sabour, A. Shokry, M. Soliman (NRIAG), X. F. Wang (THU/BJP), J. Zhu (BJP), X. Y. Zeng (CGTU), L. T. Wang, A. Iskandar (XAO), K. Smith (UVI), P. Gokuldass (Florida Tech) N. Orange (OrangeWave Innovative Science, LLC), T. Hussenot (IJCLab), A. M. Fouad (NRIAG), A. Takey(NRIAG), H. A. Ismail, M. Abdel-Sabour (NRIAG), D. A. Kann (Goethe Univ.) report on behalf of the GRANDMA collaboration: The GRANDMA telescope network responded to the Swift-BAT alert of GRB 221110A (M. A. Williams et al., GCN 32925, P.A. Evans et al. GCN 32929) detected at 02:28:17.62 UT. An afterglow was immediately detected by UVOT with the estimated magnitude of 18.62 with a 1-sigma error of ~0.07 at XRT (not refined) position RA, Dec: 29.09928, -27.29435. The VLT/X-shooter spectroscopic observations (L. Izzo et al., GCN 32928) reported a high-z candidate at z=4.06. The first GRANDMA observations started 40 s after the BAT trigger time with TCH telescope at La Silla, Chile. Below, we report selected observations. We also report our 5-sigma upper limits. Magnitudes are given in the AB system. T-T0(hr)| MJD | Obser. | Exposure | Filter | Mag +/- err|Upp.Lim _______________________________________________________________________________ 0.06 |59893.105660| TCH | 5x30s | clear | 15.9+/-0.1 | 17.2 3.3 |59893.242788| SOAR | 1x300s | sdssr | 21.7+/-0.2 | - 3.3 |59893.246601| SOAR | 1x300s | sdssi | 19.8+/-0.1 | - 3.3 |59893.238496| SOAR | 1x300s | sdssz | 19.4+/-0.2 | - 8.1 |59893.440510| KNC-SSO | 5x300s | Ic | - | 19.0 17.6 |59893.835694| KAO | 10x250s | sdssz | - | 19.9 18.7 |59893.881065| KNC-HAO | 20x180s | R | - | 19.8 19.3 |59893.905405| MOSS | 60x60s | clear | - | 20.4 25.1 |59894.149306| VIRT | 400x10s | R | - | 20.1 These observations are consistent with previous reports by LCOGT (R. Strausbaugh et al GCN 32926) and COATLI (M. Pereyra et al. GCN 32927). TCH and MOSS data have been calibrated using nearby stars from the Pan-STARRS catalogue in sdss-r measured with STDpipe (Karpov 2022). KNC-HAO data have been calibrated with respect to field stars from the Pan-STARRS and APASS catalogues, using the MUPHOTEN pipeline (Duverne et al. 2022). The upper limit derived for KAO data was defined with the faintest detected star in the field and the images were processed with IRAF. SOAR used the "Goodman Spectroscopic Pipeline" for imaging processing and IRAF for getting the astrometric solution. The photometric calibration was done by comparison with SkyMapper sources in the field in SDSS. The images of iTelescope 32 (Siding Spring Observatory, Australia) have been processed using the STDpipe and photometry was performed using field stars from the PanSTARRS1-i catalogue as a reference. VIRT data was processed with the in-house pipeline which uses the USNO.B1 catalogue. The nearly full Moon contaminated the observations. GRANDMA is a worldwide telescope network (grandma.ijclab.in2p3.fr) devoted to the observation of transients in the context of multi-messenger astrophysics (Antier et al. 2020 MNRAS 497, 5518). Kilonova-Catcher (KNC) is the citizen science program of GRANDMA (http://kilonovacatcher.in2p3.fr/).