TITLE: GCN CIRCULAR NUMBER: 16853 SUBJECT: GRB 140928A: LCO-Cerro Tololo further observations DATE: 14/09/30 10:36:59 GMT FROM: Cristiano Guidorzi at Ferrara U,Italy C. Guidorzi (U. Ferrara), D. Kopac, C. Mundell (LJMU), S. Dichiara (U. Ferrara) on behalf of a large collaboration report: Using the Las Cumbres Observatory Global Telescope Network (LCOGTN) 1-m telescope in Cerro Tololo (Chile), we re-observed Fermi GRB 140928A (Desiante et al., GCN 16847; von Kienlin and Meegan GCN 16850) in the r' filter starting on September 30, 07:14:36 UT, i.e. ~1.86 days after the Fermi trigger time. The optical afterglow (Varela et al., GCN 16849; Kopac et al. GCN 16851) is still clearly detected with R = 21.2 +/- 0.1 mag at a mid time of 1.88 days post burst (total exposure of 1680 s). The magnitude is calibrated against nearby USNO-B1 stars. A comparison with our previous report (Kopac et al.) suggests an average power-law decay index alpha = 1.2 +- 0.2.