Aliu, E.Barrio, J. A.Bordas Coma, PolBosch i Ramon, ValentíCamara, M.Contreras, J. L.Cortina Blanco, JuanReyes, R. de losErrando, M.Miranda, J. M.Moralejo, AbelardoNieto, D.Oya, I.Paredes i Poy, Josep MariaPuchades, N.Ribó Gomis, MarcSidro Martín, NúriaTescaro, DiegoZabalza de Torres, VíctorZanin, Roberta2013-07-192013-07-1920080036-8075https://hdl.handle.net/2445/44966One 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 γ-ray Imaging Cherenkov (MAGIC) telescope to 25 giga-electron volts. In this configuration, we detected pulsed γ-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.10 p.application/pdfeng(c) Aliu, E. et al., 2008PúlsarsTelescopis espacialsElectromagnetismeAstronomia de raigs gammaMagnetosferaRadiació sincrotrònicaPulsarsSpace telescopesElectromagnetismGamma ray astronomyMagnetosphereSynchrotron radiationinfo:eu-repo/semantics/article5673642013-07-19info:eu-repo/semantics/openAccess18927358