INVESTIGADORES
HANSEN Patricia Maria
congresos y reuniones científicas
Título:
First steps towards the search for evidence of split-SUSY at Auger.
Autor/es:
P. HANSEN, S.J.SCIUTTO, J. ALVAREZ-MUÑIZ, T. PAUL AND L. ANCHORDOQUI
Lugar:
Malargue, Mendoza
Reunión:
Otro; Auger Collaboration Meeting, Malargue, (March-2012).; 2012
Resumen:
There exist a number of new-physics scenerios which predict strongly interacting massive particles. If such particles constitute some fraction of the cosmic ray flux, they could induce unique shower morphologies which could be searched for in the data. Here, we consider one particular class of theories, namely split-SUSY, in order to eventually arrive at an estimate of  the potential for a discovery or a bound in the context of this theory. Split-SUSY predicts longlived, massive supersymmetric particles called R-hadrons . The extremely low inelasticity of the R-hadrons in their collisions with air molecules results in a distinct shower characteristics.The leading particle retains most of its energy all the way to the ground, while the secondary particles promptly cascade to low energies as for any other air shower. This results in an ensemble of mini-showers strung along the trajectory of the leading particle. Since the typical distance between mini-showers is about 10 times smaller than the extent of a single longitudinal profile, it is not possible to resolve the individual showers experimentally. Instead one observes an envelope encompassing all the mini-showers with a significant electromagnetic component at the ground. By selecting inclined showers the sensitivity to R-hadrons is enhanced. In thiswork we explore the characteristics of inclined showers induced by R-hadrons at the Surface Detector (SD) of the Pierre Auger Observatory and compare them to inclined proton and neutrino-induced showers (the background). This is a first preliminary work with the aim of exploring observables capable of separating R-hadrons from background showers. We show that R-hadron induced showers can be discriminated from proton-induced showers using a Fisher Discriminant Method to establish cuts to maximize the identification efficiency. Though R-hadron and neutrino-induced showers are harder to separate, this is not an obstacle to placea limit on R-hadron production if no candidates are found. Though the study presented here was conducted in the context of a specific theoretical model (split-SUSY), we emphasize that the techniques apply in general to any theory involving stable, long-lived strongly interacting particles.