Simulation of UHE muons propagation for GEANT3

A simulation package for the transport of high energy muons has been developed. It has been conceived to replace the muon propagation software modules implemented in the detector simulation program GEANT3. Here we discuss the results achieved with our package and we check the agreement with numerical calculations up to 10**8 GeV.Comment: 21 pages, 6 figures, 1 Table. AMSTeX document, acknowledgments adde

UHE and EHE neutrino induced taus inside the Earth

Tau neutrinos interacting inside the Earth produce $\tau$ leptons which thereafter can decay inside the atmosphere. The propagation of extremely energetic \nut's and $\tau$'s through the Earth is studied by means of a detailed Monte Carlo simulation, taking into account all major mechanisms of \nut interactions and $\tau$ energy loss as well as decay modes. The rates of $\tau$'s emerging from the Earth are determined as a function of $\tau$'s energy for several cosmic neutrino models.Comment: 21 pages, accepted for publication in Astroparticle Physic

ACTIVIDAD CELULOLITICA DE CEPAS DE Aspergillus niger y A. flavus AISLADAS DE SUELOS CON CULTIVO DE TRIGO Y TRATAMIENTO HERBICIDA

Se estudia la actividad celulolítica de cepas de Aspergillus niger y A. flavus aisladas de suelo del sur de la provincia de Santa Fe, sembrado con trigo y tratado con Metsulfurón-metil+Dicamba. Dichas cepas fueron las más frecuentes en un muestreo que abarcó distintas etapas del cultivo de trigo en 1994 y mostraron a su vez, variaciones en su frecuencia a lo largo del mismo.Nuestro objetivo fue conocer si dichas variaciones de frecuencia se correlacionan con cambios en la actividad celulolítica de las mismas. Se trabajó con 3 cepas deA. niger y 2 de A. flavus. En los filtrados de los cultivos, se determinó: peso seco, proteínas solubles, producción de exoglucanasas frente a la celulosa cristalina, endoglucanasas frente a carboximetilcelulosa y celobiasas extracelulares.En A. niger, no hubo una correlación clara entre frecuencia y actividad  enzimática, sólo se observó que las cepas de A. niger de mayor frecuencia (superior al 50%) tuvieron también mayor actividad. En A. flavus, encambio, se observó una correlación inversa

ESAF: Full Simulation of Space-Based Extensive Air Showers Detectors

Future detection of Extensive Air Showers (EAS) produced by Ultra High Energy Cosmic Particles (UHECP) by means of space based fluorescence telescopes will open a new window on the universe and allow cosmic ray and neutrino astronomy at a level that is virtually impossible for ground based detectors. In this paper we summarize the results obtained in the context of the EUSO project by means of a detailed Monte Carlo simulation of all the physical processes involved in the fluorescence technique, from the Extensive Air Shower development to the instrument response. Particular emphasis is given to modeling the light propagation in the atmosphere and the effect of clouds. Main results on energy threshold and resolution, direction resolution and Xmax determination are reported. Results are based on EUSO telescope design, but are also extended to larger and more sensitive detectors.Comment: 38 pages, 48 figures Corrected typos. Changed content. Added figure