Recent follow-up observations of GRBs in the very high energy band with the MAGIC telescopes

Gamma ray burst (GRBs) are primary targets for all modern IACT telescopes. The MAGIC collaboration has identified the detection of GRBs in the VHE regime as one of its multi-year key observational programs (KOP). However, the transient and unpredictable nature of GRBs makes pointing and rapid follow-up observations to observe the prompt emission phase difficult for large ground-based Cherenkov facilities. Thanks to its fast pointing speed and low-energy sensitivity, MAGIC is particularly well suited for GRB studies in the VHE range below 100 GeV during the prompt-to-early afterglow phase. Since the beginning of operation in 2004-2005, MAGIC has performed 74 follow-up observations that, to date, have yielded no significant detections. However, in the last two years, the upgrade of the MAGIC system and an improved GRB observation procedure has made possible follow-up of GRBs within 100s after the event onset, thus opening a new phase in the study of GRBs with MAGIC. In this contribution, I report on the achieved performance and some characteristics of the GRBs observed with MAGIC, with particular focus on those observed after the performance improvements in 2013.