Reconstruction of the muon lateral distribution with AMIGA revisited

D. RAVIGNANI; D. MELO; A. D. SUPANITSKY

PUBLICACION INTERNA DE LA COLABORACION INTERNACIONAL AUGER

The Observatory Pierre Auger

Año: 2014 p. 1 - 10

2250-835X

We present in this note a profile likelihood to reconstruct the muon lateral distribution function (MLDF) with the AMIGA muon counter array. This new likelihood combines the detector time resolution of the original reconstruction introduced in [1] with the exact likelihood presented in [2, 3]. The exact likelihood is not the best option because it has to assume a single time window, so cannot benefit from the detector time resolution. The proposed likelihood is an approximation to the full likelihood based on the profiling technique used to get rid of nuisance parameters (see Ref. [4] for example). We show that the new likelihood allows a better mass separation between proton and iron primaries than the exact likelihood. We also argue that at energies higher than 3 EeV a more meaningful mass classification can be achieved with AMIGA using the profile likelihood instead of theoriginal reconstruction method.