How To Select Uhecr In Euso The Trigger System

Elias Garcia, 14-1, 1000-149 Lisboa, Portugal EUSO is a space mission to detect Ultra High Energy Cosmic Rays (UHECR) by collecting the Ultra-Violet light generated by UHECR in its interaction with Earth's atmosphere. The online discrimination of events from the background requires several triggering levels and sophisticated algorithms. In this paper the trigger system is described. EUSO Extreme Universe Space Observatory 1 is a space based fluorescence detector for UHECR detection that...

And The Magic Collaboration

With its diameter of 17m, the MAGIC telescope is the largest Cherenkov detector for gamma ray astrophysics, and it has the lowest energy threshold (well below 100 GeV). MAGIC started operations in October 2003 and is currently taking data. This report summarizes its main characteristics, its first results and its potential for physics. The MAGIC (Major Atmospheric Gamma Imaging Cherenkov) telescope has been designed 1 with the aim to achieve the lowest possible gamma energy threshold with a...

Maia

CICGE, Faculdade de Ciencias da Universidade do Porto, Observatorio Astron'omico, Alameda do Monte da Virgem 4430-146 Vila Nova de Gaia, Portugal E-mail dmaia fe.up.pt Particle acceleration is ubiquitous in all forms of coronal activity. The question is where, when, and how are those particles accelerated In the Sun this question can be answered by using spatially resolved observations of the electromagnetic emissions and in-situ measures of plasmas in the heliosphere. In order to relate the...

Xhard QCDSpcrutoff Asb4

Where the normalized profile function, d2b A(s, b) 1, indicates the distribution of partons in the plane transverse to the collision axis. In the QGSJET-like models, the core of the hard eikonal is dressed with a soft-pomeron pre-evolution factor. This amounts to taking a parton distribution which is Gaussian in the transverse coordinate distance 6 . In SIBYLL-Iike models, the transverse density distribution is taken as Figure 2. Left panel The slowly rising curves indicate the mean...

Testing Covariant Entropy Bounds

Centro Multidisciplinar de Astrof sica - CENTRA Departamento de F sica, Instituto Superior T cnico Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal E-mail sijie fisica.ist.utl.pt, lemos fisica.ist.utl.pt We give a brief review on Bousso's covariant entropy bound and its generalization. Bousso's bound is tested in the context of gravitational collapse. We also introduce a simple local condition for the generalized Bousso bound and apply it to a scalar field spacetime. The original entropy bound was...

Centra

Elias Garcia 14, 1o 1000-149 Lisboa Portugal gaspar lip.pt Orfeu Bertolami Instituto Superior T cnico Departamento de F sica Av. Rovisco Pais 1049-001 Lisboa Portugal Av. Elias Garcia 14, 1o 1000-149 Lisboa Portugal goncalo lip.pt Pedro Brogueira Instituto Superior T cnico Departamento de F sica Av. Rovisco Pais 1049-001 Lisboa Portugal pedro fisica.ist. utl.pt Vitor Cardoso McDonnell Center for the Space Sciences Department of Physics Washington University, St. Louis MO 63130 USA Av. Elias...

Rui Neves

Departamento de F sica, Faculdade de Ciencias e Tecnolog a Centro Multidisciplinar de Astrof sica-CENTRA Campus de Gambelas, 8005-139 Faro, Portugal E-mail rneves ualg.pt In the Randall-Sundrum scenario we analize the dynamics of a spherically symmetric 3-brane when matter fields propagate in the bulk. For a well defined class of conformal fields of weight -4 we determine a new set of exact 5-dimensional solutions which localize gravity in the vicinity of the brane and are stable under radion...

Info

Our braneworld backgrounds correspond to the metric functions 6 1, B B(t, r), R R(t, r) and a Q(y). To calculate the radion potential we consider the dimensional reduction of (11). Using the metric with a(t,r,y) fand b(t,r) e0 we obtain in the Einstein frame 25 S J d4x f4 _ ivc7Vd754Cd - Vj , (12) where 7 3 (t 4- 2 3) is the canonically normalized radion field. The function V (7) is the radion potential and it is given by 3 J dyQ.2 dvnf + 2 J dyQ d2yQ. + X J dyn4 (ab - LB) +X2 J dyn4 Ai (y) +...

Vitor Cardoso

McDonnell Center for the Space Sciences, Department of Physics, Washington University, St. Louis, Missouri 63130, USA and Centro de F sica Computacional, Universidade de Coimbra, P-3004-516 Coimbra, Portugal E-mail vcardoso wugrav. wustl. edu We discuss some general aspects of acoustic black holes. We begin by describing the associated formalism with which acoustic black holes are established, then we show how to model arbitrary geometries by using a de Laval nozzle. The progress in...

B

Left - Total energy deposited in the crystal by incident protons, expressed as the fraction of the initial particle energy. Right - Simulated time spectrum of the hits in the photodetectors. The principle of the anti-coincidence operation mode is illustrated in the rigth plot of Fig. 2. It shows the time of the simulated hits in the photodiodes, produced by a 100 MeV proton that is not stopped inside the crystal. The fast signal at time zero is due to the direct ionization produced by...