%0 Journal Article
%A Antoranz Canales, Pedro
%A Barrio Uña, Juan Abel
%A Contreras González, José Luis
%A Fonseca González, María Victoria
%A Miranda Pantoja, José Miguel
%A Nieto Castaño, Daniel
%T Observation of pulsed gamma-rays above 25 GeV from the Crab Pulsar with MAGIC
%D 2008
%@ 0036-8075
%U https://hdl.handle.net/20.500.14352/50806
%X One fundamental question about pulsars concerns the mechanism of their pulsed electromagnetic emission. Measuring the high- end region of a pulsar's spectrum would shed light on this question. By developing a new electronic trigger, we lowered the threshold of the Major Atmospheric gamma-ray Imaging Cherenkov (MAGIC) telescope to 25 giga-electron volts. In this configuration, we detected pulsed gamma-rays from the Crab pulsar that were greater than 25 giga-electron volts, revealing a relatively high cutoff energy in the phase- averaged spectrum. This indicates that the emission occurs far out in the magnetosphere, hence excluding the polar- cap scenario as a possible explanation of our measurement. The high cutoff energy also challenges the slot- gap scenario.
%~