Speaker
Irene BOLOGNINO
(PhD student)
Description
ARGO-YBJ is an extensive air shower detector located at the Yangbajing Cosmic Ray Laboratory (Tibet, China) at 4300 m a.s.l. IT is made by a full coverage carpet plus a guard ring (total surface ~6700 m2) of Resistive Plate Chambers grouped into 153 units called "clusters". The experiment has continually worked since November 2007 recording events with an energy threshold of ~ 300GeVs and with a duty cycle of ~90%. The lowest energy threshold (few GeVs) is obtained using the "scaler operation mode" counting events for every cluster with a number of particles ≥1, ≥2, ≥3, ≥4, in order to detect cosmic rays flux variations and gamma-ray bursts. Its structure and the high altitude allow exhaustive studies of gamma astronomy with similar energy range of Cherenkov telescopes. This talk emphazises the results of ARGO-YBJ in gamma astronomy. In particular the TeV emissions of the blazar Markarian 421, the analysis of its last two flares in 2008 and 2010 and the comparison of the Cherenkov telescopes ones are presented and discussed.
