Search for ultrarelativistic magnetic monopoles with the Pierre Auger Observatory

THE PIERRE AUGER COLLABORATION, INCLUYE S. MOLLERACH

PHYSICAL REVIEW D - PARTICLE AND FILDS

American Physical Society

Año: 2016

0556-2821

We present a search for ultrarelativistic magnetic monopoles with thePierre Auger observatory. Such particles, possibly a relic of phasetransitions in the early Universe, would deposit a large amount ofenergy along their path through the atmosphere, comparable to that ofultrahigh-energy cosmic rays (UHECRs). The air-shower profile of amagnetic monopole can be effectively distinguished by the fluorescencedetector from that of standard UHECRs. No candidate was found in thedata collected between 2004 and 2012, with an expected background ofless than 0.1 event from UHECRs. The corresponding 90% confidence level(C.L.) upper limits on the flux of ultrarelativistic magnetic monopolesrange from 10-19(cm2 sr s )-1 for aLorentz factor γ =1 09 to 2.5×10-21(cm2 sr s )-1 for γ=1 012. These results?the first obtained with a UHECRdetector?improve previously published limits by up to an order ofmagnitude.