7,549 research outputs found
A model for multifragmentation in heavy-ion reactions
From an experimental point of view, clear signatures of multifragmentation
have been detected by different experiments. On the other hand, from a
theoretical point of view, many different models, built on the basis of totally
different and often even contrasting assumptions, have been provided to explain
them. In this contribution we show the capabilities and the shortcomings of one
of this models, a QMD code developed by us and coupled to the nuclear
de-excitation module taken from the multipurpose transport and interaction code
FLUKA, in reproducing the multifragmentation observations recently reported by
the INDRA collaboration for the reaction Nb + Mg at a 30 MeV/A projectile
bombarding energy. As far as fragment production is concerned, we also briefly
discuss the isoscaling technique by considering reactions characterized by a
different isospin asymmetry, and we explain how the QMD + FLUKA model can be
applied to obtain information on the slope of isotopic yield ratios, which is
crucially related to the symmetry energy of asymmetric nuclear matter.Comment: 8 pages, 2 figures, Proc. 12th International Conference on Nuclear
Reaction Mechanisms, Varenna, Italy, June 15 - 19 200
High energy extension of the FLUKA atmospheric neutrino flux
The atmospheric neutrino flux calculated with FLUKA was originally limited to
100-200 GeV for statistical reasons. In order to make it available for the
analysis of high energy events, like upward through-going muons detected by
neutrino telescopes, we have extended the calculation so to provide a reliable
neutrino yield per primary nucleon up to about 10**6 GeV/nucleon, as far as the
interaction model is concerned. We point out that the primary flux model above
100 GeV/nucleon still contributes with an important systematic error to the
neutrino flux.Comment: Extended version (10 pages) of the contribution to ICRC 2003, with
the addition of flux table
The FLUKA Monte Carlo, non-perturbative QCD and Cosmic Ray cascades
The FLUKA Monte Carlo code, presently used in cosmic ray physics, contains
packages to sample soft hadronic processes which are built according to the
Dual Parton Model. This is a phenomenological model capable of reproducing many
of the features of hadronic collisions in the non perturbative QCD regime. The
basic principles of the model are summarized and, as an example, the associated
Lambda-K production is discussed. This is a process which has some relevance
for the calculation of atmospheric neutrino fluxes.Comment: Extended version of the work for the proceedings of the workshop on
QCD at Cosmic Ray Energies, Erice, Aug. 30 - Sep. 4 2004, Ital
Atmospheric neutrinos in a Large Liquid Argon detector
In view of the evaluation of the physics goals of a large Liquid Argon TPC,
evolving from the ICARUS technology, we have studied the possibility of
performing precision measurements on atmospheric neutrinos. For this purpose we
have improved existing Monte Carlo neutrino event generators based on FLUKA and
NUX by including the 3-flavor oscillation formalism and the numerical treatment
of Earth matter effects. By means of these tools we have studied the
sensitivity in the measurement of Theta(23) through the accurate measurement of
electron neutrinos. The updated values for Delta m^2(23) from Super-Kamiokande
and the mixing parameters as obtained by solar and KamLand experiments have
been used as reference input, while different values of Theta(13) have been
considered. An exposure larger than 500 kton yr seems necessary in order to
achieve a significant result, provided that the present knowledge of systematic
uncertainties is largely improved.Comment: Talk given at the worksgop "Cryogenic Liquid Detectors for Future
Particle Physics", LNGS (Italy) March 13th-14th, 200
Beam Dumps and Beam Stoppers for LHC and CNGS Transfer Lines
Three new beam transfer lines are presently under construction at the SPS: TI2 and TI8 which will transfer protons and ions to the LHC, and TT41 which will transfer protons to the CNGS neutrino target. Three beam dumps (TED) and two beam stoppers (TBSE) will be installed in TI2 and TI8, and one TBSE in TT41. Both types of equipment are required to intercept the 450 GeV SPS beams concentrated in very short pulses (7.8 ”s-10.5 ”s) at intensities up to ~ 5 10**13 protons, every 16.8 seconds for the TED and as single shot for the TBSE. The outer TED iron shielding will be identical to the existing SPS one, while dimensions and material composition of both TED and TBSE cores have been optimised to cope with the new beam conditions. The optimised TED inner core consists of a Ă80 mm graphite cylinder 2.9 m long, housed into a Ă80/160 mm aluminium blind tube 3.5 m long, itself fitted into a Ă160/310 mm copper blind tube 4.3 m long. The TBSE is made of the same graphite cylinder, housed into a Ă80/120 mm aluminium blind tube 3.5 m long, itself fitted into a Ă120/240 mm iron blind tube 4 m long. The maximum allowed beam intensity for a safe operation is given as a function of the pulse duration, including slow pulses as presently aborted on SPS dumps. The analytical methods set out in the thermo-mechanical part of this study are of general application, and may help in many other axi-symmetrical beam deposition analyses
Hadronic interactions of primary cosmic rays with the FLUKA code
The measured fluxes of secondary particles produced by the interactions of
cosmic rays with the astronomical environment represent a powerful tool to
infer some properties of primary cosmic rays. In this work we investigate the
production of secondary particles in inelastic hadronic interactions between
several cosmic rays species of projectiles and different target nuclei of the
interstellar medium. The yields of secondary particles have been calculated
with the FLUKA simulation package, that provides with very good accuracy the
energy distributions of secondary products in a large energy range. An
application to the propagation and production of secondaries in the Galaxy is
presented.Comment: 8 pages, 4 figures; Contribution to the 34th International Cosmic Ray
Conference, July 30 to August 6, The Hague, Netherlands; fixing a typo in the
y-axis label of Fig.
CNGS neutrino beam systematics for
Energy spectra, intensity and composition of the CERN to Gran Sasso CNGS
neutrino beam for nu_mu-->nu_tau and nu_mu-->nu_e oscillation searches are
presented. The associated beam systematics, which is the major ingredient for
the nu_mu-->nu_e search sensitivity, are obtained from the study of the
previous CERN WANF.Comment: presented at NOW 2004, 5 pages, 7 figure
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