文档介绍：Astroparticle Physics 25 (2006) 375–379
ate/astropart
GZK cutoff distortion due to the energy error distribution shape
Ivone . Albuquerque a,b,*, e F. Smoot c
a Instituto Fı´sica, Universidade de Sa˜o Paulo, SP, Brazil
b Space Science Laboratory, University of California, Berkeley, CA 94720, United States
c Lawrence Berkeley National Laboratory, Space Sciences Laboratory and Department of Physics, University of California,
Berkeley, CA 94720, United States
Received 10 October 2005; received in revised form 10 March 2006; accepted 28 March 2006
Available online 2 May 2006
Abstract
The development of an ultra high energy air shower has an intrinsic energy fluctuation due both to the first interaction point and to
the cascade development. Here we show that for a given primary energy this fluctuation has a lognormal distribution and thus obser-
vations will estimate the primary energy with a lognormal error distribution. We analyze the UHECR energy spectrum convolved with
the lognormal energy error and demonstrate that the shape of the error distribution will interfere significantly with the ability to observe
features in the spectrum. If the standard deviation of the lognormal error distribution is equal or larger than , both the shape and the
normalization of the measured energy spectra will be modified significantly. As a consequence, the GZK cutoff migh