LFBOT ATeL#17646: COLIBRI detection
ATel #17647; Ramandeep Gill (UNAM), Sarah Antier (IJCLAB), Margarita Pereyra (UNAM), Rosa L. Becerra (UNAM), Alan M. Watson (UNAM), Stéphane Basa (UAR Pytheas), William H. Lee (UNAM), Edilberto Aguilar-Ruiz (UNAM), Jean-Luc Atteia (IRAP), Camila Angulo (UNAM), Dalya Akl (NYUAD), Nathaniel R. Butler (ASU), Damien Dornic (CPPM), Jean-Gregoire Ducoin (CPPM), Francis Fortin (IRAP), Leonardo Garcia Garcia (UNAM), Noemie Globus (UNAM), Asuka Kuwata (UNAM), Nikos Mandarakas (LAM), Diego Lopez-Camara (UNAM), Francesco Magnani (CPPM), Enrique Moreno Mendez (UNAM), Ny Avo Rakotondrainibe (LAM), Fredd Sanchez Alvarez (UNAM), Benjamin Schneider (LAM), and Antonio de Ugarte Postigo (LAM):
on 6 Feb 2026; 04:19 UT
Credential Certification: Alan Watson (alan@astro.unam.mx)
We observed the field of the candidate LFBOT reported by Tsuboi, Nakaoka, & Kawabata (ATeL #17646) with the DDRAGO wide-field imager on the COLIBRI telescope at the Observatorio Astronomico Nacional on the Sierra de San Pedro Martir, starting at 2026-02-06T03:09:15 UTC in the g and z filters and obtained 60-second individual images in each filter.
The data were analysed in STDWeb/STDPipe (Karpov 2025). We detected the optical transient with the following preliminary magnitudes:
g= 16.66 +/- 0.01
z= 17.01 +/- 0.02
Our photometry confirms the blue colors of this transient.
Assuming an association with one of the nearby galaxies with redshifts about 0.03 (approximately 130 Mpc) (according to the DESI Legacy Survey DR9), the magnitudes obtained are largely consistent with the ones observed for AT2018cow, the prototype FBOT, strongly suggesting the same nature for this source.
These values are not corrected for the Galactic extinction.
Further observations and analysis are ongoing.
We thank the staff of the Observatorio Astronomico Nacional on the Sierra de San Pedro Martir and the COLIBRI and DDRAGO engineering teams.
COLIBRà 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 Martir, Baja California, Mexico.
