TITLE: GCN CIRCULAR NUMBER: 32934 SUBJECT: GRB 221009A: GRANDMA/Kilonova-Catcher observations DATE: 22/11/11 17:01:38 GMT FROM: Damien Turpin at NAOC (CAS) O. Aguerre, F. Bayard, E. Broens, H-B. Eggenstein, M. Freeberg, R. Kneip (KNC), A. Lekic, B. Delaveau, E. Durand (KNC/IPSA), S. Leonini, D. Marchais, E. Maris, R. Ménard, G. Parent, M. Richmond, F. Romanov,  M. Serrau, S. Vanaverbeke (KNC), S. Antier (OCA/Artemis), D. A. Kann (Goethe Univ.), S. Karpov (FZU), A. Klotz (OMP/IRAP), T. Midavaine (SAF), D. Turpin (CEA) report on behalf of GRANDMA and Kilonova-Catcher collaborations: The Kilonova-Catcher telescope network responded to the alert of the ultra-bright GRB 221009A (Swift detection: Dichiara et al., GCN 32632; Fermi GBM detection: Veres et al., GCN 32636). In total, 220 science images sent by the KNC amateur astronomers were analyzed. The KNC observations cover the period from 6.3h to about 17.5 days after the Fermi/GBM trigger time. Below, we report a subset of these observations. Magnitudes are given in the AB system and we also report our 5-sigma upper limits. T-T0 (day)| MJD   | Obser.   |Exposure| Filter | Mag +/- err  |Upp.Lim. (AB) ___________________________________________________________________________ 0.285 | 59861.838073 | T-BRO | 5 x 180s | Ic | 15.65 +/- 0.03 | 18.0 0.578 | 59862.131620 | BGO | 60s | I | 16.58 +/- 0.07 | 17.8 1.241 | 59862.794004 | Astrolab IRIS | 14 x 180s | I | 17.47 +/- 0.07 | 18.5 1.365 | 59862.918754 | Ch-Perdrix | 10 x 180s | Clear | 18.76 +/- 0.14 | 19.2 1.447 | 59863.000000 | Ste-Sophie | 16 x 360s | TR-rgb | 18.89 +/- 0.06 | 20.4 1.531 | 59863.084675 | HVO | 59 x 120s | R | 18.93 +/- 0.09 | 19.8 1.703 | 59863.256925 | SRO Auberry | 300s | I | 17.85 +/- 0.13 | 18.1 2.217 | 59863.770555 | Montarrenti | 2 x 30s | Clear | 18.65 +/- 0.24 | 18.5 2.229 | 59863.782465 | EHEA-WL | 199 x 32s | I | 18.64 +/- 0.21 | 18.7 2.267 | 59863.820289 | CO-K26 | 8884s | Lum | -- | 19.7 2.308 | 59863.861789 | GPO | 5700s | Clear | -- | 19.8 2.522 | 59864.075696 | LCO-MDO | 7 x 180s | sdss-r | 19.56 +/- 0.12 | 20.2 2.555 | 59864.108314 | NMSkies | 11 x 300s | Ic | 18.74 +/- 0.13 | 19.3 3.250 | 59864.803399 | Atlas | 30 x 120s | R | -- | 18.4 5.323 | 59866.876810 | Crous Gats | 180 x 32s | TR-rgb | 20.46 +/- 0.14 | 21.0 These detections and limits are consistent with the detections and limits previously reported in Lipunov et al., GCN 32634; Perley, GCN 32638; Broens, GCN 32640; Hu et al., GCN 32644; Belkin et al., GCN 32645; GCN 32769 ; Wet et al., GCN 32646; Xu et al., GCN 32647; de Ugarte Postigo et al., GCN 32648, 32800; Odeh, GCN 32649; GCN 32666; Brivio et al., GCN 32652; Kuin et al., GCN 32656; Paek et al., GCN 32659; Kumar et al., GCN 32662; Romanov, GCN 32664; 32679; Chen et al., GCN 32667; Vidal et al., GCN 32669; Kim et al., GCN 32670; Groot et al., GCN 32678; Castro-Tirado et al., GCN 32686; Watson et al., GCN 32692; Strausbaugh et al. GCN 32693; Butler et al., GCN 32705; Vinko et al., GCN 32709; Mao et al., GCN 32727; Zaznobin et al., GCN 32729; Sasada et al., GCN 32730; Strausbaugh & Cucchiara, GCN 32738; O'Connor et al., GCN 32739; GCN 32750, GCN 32799, GCN 32860; Bikmaev et al., GCN 32743; GCN 32752; Rastinejad & Fong, GCN 32749; Schneider et al., GCN 32753; D’Avanzo et al., GCN 32755; Huber et al., GCN 32758; Shrestha et al., GCN 32759; 32771; Izzo et al., GCN 32765; Levan et al., GCN 32821, GCN 32921; Maiorano et al., GCN 32850; Pellegrin et al., GCN 32852. The GRANDMA/Kilonova-Cacther images have been calibrated using field stars from the PanSTARRS-DR1 catalog using the STDpipe pipeline (Karpov 2022). We advocate a joint multi-wavelength publication for this event and we are happy to collaborate with teams that have the same spirit, to be able to explore the best astrophysical scenario. 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/).