Three years’ systematic GRB follow-up at the Xinglong Observatory and the optical afterglow observations of GRB 080330

We present a brief overview of follow-up observations of GRB afterglows made by the 0.8-m TNT and other telescopes at the Xinglong observatory during the last three years. Our system, dedicated to the measurement of early-time optical afterglow emission, responded to 50 GRBs from Jan. 2006 to Apr. 2009. Among them, about 50% have been successfully detected. The fastest response time is 76 sec (GRB 061110A and GRB 090426) after the space-borne GRB detector was triggered. The redshift distribution spans the range from z = 0.033 (GRB 060218) to z = 5.6 (GRB 060927). We also report the optical photometric follow-up of GRB 080330, which is an X-ray flash, as an example of our observations.