TITLE: GCN CIRCULAR NUMBER: 28572 SUBJECT: GRB 201006A: Lowell Discovery Telescope upper limits DATE: 20/10/07 14:35:50 GMT FROM: Simone Dichiara at UMCP/NASA/GSFC S.Dichiara (UMD, NASA-GSFC), S.B. Cenko (NASA-GSFC), E. Troja (UMD, NASA-GSFC), P. Gatkine (UMD), J.M. Durbak (UMD), A. Kutyrev (UMD, NASA-GSFC), S. Veilleux (UMD), report on behalf of a larger collaboration: We observed the field of the short GRB 201006A (Gropp et al., GCN Circ. 28560) using the Large Monolithic Imager (LMI) on the 4.3m Lowell Discovery Telescope (LDT) at Happy Jack, AZ. Observations started on October 7, 11:50:54 UT (1.44 days after the Swift trigger) taking 3 exposures of 150 s each with SDSS i filter. Observations were taken at an airmass of about 1.19 and seeing of about 0.5". We do not find any source inside the enhanced XRT position (Goad et al., GCN Circ. 28562) down to a 3-sigma limiting magnitude of i>23.8 AB mag. Magnitudes are calibrated against the PanSTARRS catalog and not corrected for Galactic extinction. We thank the staff of the Lowell Discovery Telescope for assistance with these observations.