1,870 research outputs found
a distributed data acquisition system for nuclear detectors
Nowadays, many examples of data acquisition (DAQ) software for experimental nuclear physics are monolithic processes that run on a computer attached to the DAQ hardware. In this article we present a distributed DAQ system developed for the C-BORD project. With our system, we propose a novel approach, in which each task related to the different DAQ parts (acquisition, pre-process, analysis, etc.) runs in a separate process. In particular, the system is composed of a set of servers that exchange information through dedicated communication sockets. Therefore, with this architecture, an important advantage is the possibility to run the processes on different computers to distribute the computational load. The initial tests of the system have been giving excellent results, both in terms of performance (i.e., maximum acquisition rates) and stability. The project entitled "Effective container inspection at BORDer control points" (C-BORD) is funded by the European H2020 programme. Its aim is to develop a comprehensive set of technologies for the generalized non-intrusive inspection (NII) of containers and large-volume freight at the European Union border
Elastic scattering of O-17+Pb-208 at energies near the Coulomb barrier
Within the frame of the commissioning of a new experimental apparatus EXPADES we undertook the measurement of the elastic scattering angular distribution for the system O-17+Pb-208 at energy around the Coulomb barrier. The reaction dynamics induced by loosely bound Radioactive Ion Beams is currently being extensively studied [4]. In particular the study of the elastic scattering process allows to obtain direct information on the total reaction cross section of the exotic nuclei. In order to understand the effect of the low binding energy on the reaction mechanism it is important to compare radioactive weakly bound nuclei with stable strongly-bound nuclei. In this framework the study of the O-17+Pb-208 elastic scattering can be considered to be complementary to a previous measurement of the total reaction cross section for the system F-17+Pb-208 at energies of 86, 90.4 MeV [5, 6]. The data will be compared with those obtained for the neighboring systems O-16,O-18+Pb-208 and others available in literature
Performance of ALICE pixel prototypes in high energy beams
The two innermost layers of the ALICE inner tracking system are instrumented
with silicon pixel detectors. Single chip assembly prototypes of the ALICE
pixels have been tested in high energy particle beams at the CERN SPS.
Detection efficiency and spatial precision have been studied as a function of
the threshold and the track incidence angle. The experimental method, data
analysis and main results are presented.Comment: 10 pages, 9 figures, contribution to PIX2005 Workshop, Bonn
(Germany), 5-8 September 200
Beam Test Performance and Simulation of Prototypes for the ALICE Silicon Pixel Detector
The silicon pixel detector (SPD) of the ALICE experiment in preparation at
the Large Hadron Collider (LHC) at CERN is designed to provide the precise
vertex reconstruction needed for measuring heavy flavor production in heavy ion
collisions at very high energies and high multiplicity. The SPD forms the
innermost part of the Inner Tracking System (ITS) which also includes silicon
drift and silicon strip detectors. Single assembly prototypes of the ALICE SPD
have been tested at the CERN SPS using high energy proton/pion beams in 2002
and 2003. We report on the experimental determination of the spatial precision.
We also report on the first combined beam test with prototypes of the other ITS
silicon detector technologies at the CERN SPS in November 2004. The issue of
SPD simulation is briefly discussed.Comment: 4 pages, 5 figures, prepared for proceedings of 7th International
Position Sensitive Detectors Conference, Liverpool, Sept. 200
INFN What Next: Ultra-relativistic Heavy-Ion Collisions
This document was prepared by the community that is active in Italy, within
INFN (Istituto Nazionale di Fisica Nucleare), in the field of
ultra-relativistic heavy-ion collisions. The experimental study of the phase
diagram of strongly-interacting matter and of the Quark-Gluon Plasma (QGP)
deconfined state will proceed, in the next 10-15 years, along two directions:
the high-energy regime at RHIC and at the LHC, and the low-energy regime at
FAIR, NICA, SPS and RHIC. The Italian community is strongly involved in the
present and future programme of the ALICE experiment, the upgrade of which will
open, in the 2020s, a new phase of high-precision characterisation of the QGP
properties at the LHC. As a complement of this main activity, there is a
growing interest in a possible future experiment at the SPS, which would target
the search for the onset of deconfinement using dimuon measurements. On a
longer timescale, the community looks with interest at the ongoing studies and
discussions on a possible fixed-target programme using the LHC ion beams and on
the Future Circular Collider.Comment: 99 pages, 56 figure
Study of the transverse mass spectra of strange particles in Pb-Pb collisions at 158 A GeV/c
The NA57 experiment has collected high statistics, high purity samples of
\PKzS and \PgL, and hyperons produced in Pb-Pb collisions at 158
GeV/. In this paper we present a study of the transverse mass spectra of
these particles for a sample of events corresponding to the most central 53% of
the inelastic Pb-Pb cross-section. We analyse the transverse mass distributions
in the framework of the blast-wave model for the full sample and, for the first
time at the SPS, as a function of the event centrality.Comment: 22 pages, 14 figures, submitted to J. Phys. G: Nucl. Phy
New results from the NA57 experiment
We report results from the experiment NA57 at CERN SPS on hyperon production
at midrapidity in Pb-Pb collisions at 158 GeV/ and 40 GeV/.
, and yields are compared with those from the STAR
experiment at the higher energy of the BNL RHIC. , , \
and preliminary transverse mass spectra are presented and interpreted
within the framework of a hydro-dynamical blast wave model.Comment: 8 pages, 3 figures, contribution to the proceedings of The XXXVIIIth
Rencontres de Moriond "QCD and High Energy Hadronic Interactions
Rapidity distributions around mid-rapidity of strange particles in Pb-Pb collisions at 158 GeV/c
The production at central rapidity of K0s, Lambda, Xi and Omega particles in
Pb-Pb collisions at 158 A GeV/c has been measured by the NA57 experiment over a
centrality range corresponding to the most central 53% of the inelastic Pb-Pb
cross section. In this paper we present the rapidity distribution of each
particle in the central rapidity unit as a function of the event centrality.
The distributions are analyzed based on hydrodynamical models of the
collisions.Comment: 15 pages, 10 figure
Strangeness enhancements at central rapidity in 40 A GeV/c Pb-Pb collisions
Results are presented on neutral kaon, hyperon and antihyperon production in
Pb-Pb and p-Be interactions at 40 GeV/c per nucleon. The enhancement pattern
follows the same hierarchy as seen in the higher energy data - the enhancement
increases with the strangeness content of the hyperons and with the centrality
of collision. The centrality dependence of the Pb-Pb yields and enhancements is
steeper at 40 than at 158 A GeV/c. The energy dependence of strangeness
enhancements at mid-rapidity is discussed.Comment: 15 pages, 10 figures and 3 tables. Presented at International
Conference on Strangeness in Quark Matter (SQM2009), Buzios, Rio de Janeiro,
Brazil, 27 Sept - 2 Oct 2009. Submitted to J.Phys.G: Nucl.Part.Phys, one
reference adde
Expansion dynamics of Pb-Pb collisions at 40 A GeV/c viewed by negatively charged hadrons
In this paper we present results on transverse mass spectra and Hanbury-Brown
and Twiss correlation functions of negatively charged hadrons, which are
expected to be mostly negative pions, measured in Pb-Pb collisions at 40 A
GeV/c beam momentum. Based on these data, the collision dynamics and the
space-time extent of the system at the thermal freeze-out are studied over a
centrality range corresponding to the most central 53% of the Pb--Pb inelastic
cross section. Comparisons with freeze-out conditions of strange particles and
HBT results from other experiments are discussed.Comment: 29 pages, 18 figure
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