2,897 research outputs found
The current progress of the ALICE Ring Imaging Cherenkov Detector
Recently, the last two modules (out of seven) of the ALICE High Momentum
Particle Identification detector (HMPID) were assembled and tested. The full
detector, after a pre-commissioning phase, has been installed in the
experimental area, inside the ALICE solenoid, at the end of September 2006. In
this paper we review the status of the ALICE/HMPID project and we present a
summary of the series production of the CsI photo-cathodes. We describe the key
features of the production procedure which ensures high quality photo-cathodes
as well as the results of the quality assessment performed by means of a
specially developed 2D scanner system able to produce a detailed map of the CsI
photo-current over the entire photo-cathode surface.
Finally we present our recent R&D efforts toward the development of a novel
generation of imaging Cherenkov detectors with the aim to identify, in heavy
ions collisions, hadrons up to 30 GeV/c.Comment: Presented at the Imaging-2006 Conference, Stockholm, Sweden, June
200
Bianchi Type I Universes with Causal Bulk Viscous Cosmological Fluid
We consider the dynamics of a causal bulk viscous cosmological fluid filled
constantly decelerating Bianchi type I space-time. The matter component of the
Universe is assumed to satisfy a linear barotropic equation of state and the
state equation of the small temperature Boltzmann gas. The resulting
cosmological models satisfy the condition of smallness of the viscous stress.
The time evolution of the relaxation time, temperature, bulk viscosity
coefficient and comoving entropy of the dissipative fluid is also obtained.Comment: 11 pages, 5 figures, accepted for publication in International
Journal of Modern Physics
How ‘Smart’ Are Smart Specialization Strategies?
The introduction of smart specialization (S3) as a fundamental pillar of the 2014 reform of the EU cohesion policy is a significant strategic shift in European development intervention. S3 strategies aimed at mobilizing the economic potential of each country and region of the EU by allowing a more place-based and bottom-up approach to development. However, despite the salience that S3 has acquired in a short period of time, there has been no European-wide evaluation of the extent to which S3 strategies truly reflect the economic characteristics and potential of the territories where they are being implemented. This article examines the characteristics of S3 strategies across Europe – by focusing on their development axes, economic or scientific domains and policy priorities – to assess whether this is the case. The results show that S3 strategies display a proliferation of objectives, a problem that particularly affects areas with weaker quality of government. Moreover, strategies are generally loosely connected with the intrinsic conditions of each region and mostly mimic what neighbouring areas are doing. The lack of more concise and focused S3 strategies is likely to undermine the effectiveness of what is, otherwise, a very interesting and worthwhile policy experiment
Touching with the eyes: Oculomotor self-touch induces illusory body ownership
Self-touch plays a central role in the construction and plasticity of the bodily self. But which mechanisms support this role? Previous accounts emphasize the convergence of proprioceptive and tactile signals from the touching and the touched body parts. Here, we hypothesise that proprioceptive information is not necessary for self-touch modulation of body-ownership. Because eye movements do not rely on proprioceptive signals as limb movements do, we developed a novel oculomotor self-touch paradigm where voluntary eye movements generated corresponding tactile sensations. We then compared the effectiveness of eye versus hand self-touch movements in generating an illusion of owning a rubber hand. Voluntary oculomotor self-touch was as effective as hand-driven self-touch, suggesting that proprioception does not contribute to body ownership during self-touch. Self-touch may contribute to a unified sense of bodily self by binding voluntary actions toward our own body with their tactile consequences
VHMPID: a new detector for the ALICE experiment at LHC
This article presents the basic idea of VHMPID, an upgrade detector for the
ALICE experiment at LHC, CERN. The main goal of this detector is to extend the
particle identification capabilities of ALICE to give more insight into the
evolution of the hot and dense matter created in Pb-Pb collisions. Starting
from the physics motivations and working principles the challenges and current
status of development is detailed.Comment: 4 pages, 6 figures. To be published in EPJ Web of Conference
Dark matter search in a Beam-Dump eXperiment (BDX) at Jefferson Lab
MeV-GeV dark matter (DM) is theoretically well motivated but remarkably
unexplored. This Letter of Intent presents the MeV-GeV DM discovery potential
for a 1 m segmented plastic scintillator detector placed downstream of the
beam-dump at one of the high intensity JLab experimental Halls, receiving up to
10 electrons-on-target (EOT) in a one-year period. This experiment
(Beam-Dump eXperiment or BDX) is sensitive to DM-nucleon elastic scattering at
the level of a thousand counts per year, with very low threshold recoil
energies (1 MeV), and limited only by reducible cosmogenic backgrounds.
Sensitivity to DM-electron elastic scattering and/or inelastic DM would be
below 10 counts per year after requiring all electromagnetic showers in the
detector to exceed a few-hundred MeV, which dramatically reduces or altogether
eliminates all backgrounds. Detailed Monte Carlo simulations are in progress to
finalize the detector design and experimental set up. An existing 0.036 m
prototype based on the same technology will be used to validate simulations
with background rate estimates, driving the necessary RD towards an
optimized detector. The final detector design and experimental set up will be
presented in a full proposal to be submitted to the next JLab PAC. A fully
realized experiment would be sensitive to large regions of DM parameter space,
exceeding the discovery potential of existing and planned experiments by two
orders of magnitude in the MeV-GeV DM mass range.Comment: 28 pages, 17 figures, submitted to JLab PAC 4
The Observation of Up-going Charged Particles Produced by High Energy Muons in Underground Detectors
An experimental study of the production of up-going charged particles in
inelastic interactions of down-going underground muons is reported, using data
obtained from the MACRO detector at the Gran Sasso Laboratory. In a sample of
12.2 10^6 single muons, corresponding to a detector livetime of 1.55 y, 243
events are observed having an up-going particle associated with a down-going
muon. These events are analysed to determine the range and emission angle
distributions of the up-going particle, corrected for detection and
reconstruction efficiency. Measurements of the muon neutrino flux by
underground detectors are often based on the observation of through-going and
stopping muons produced in interactions in the rock below the
detector. Up-going particles produced by an undetected down-going muon are a
potential background source in these measurements. The implications of this
background for neutrino studies using MACRO are discussed.Comment: 18 pages, 9 figures. Accepted by Astrop. Physic
Atmospheric neutrino induced muons in the MACRO detector
A measurement of the flux of neutrino-induced muons using the MACRO detector
is presented. Different event topologies, corresponding to different neutrino
parent energies can be detected. The upward throughgoing muon sample is the
larger event sample. The observed upward-throughgoing muons are 26% fewer than
expected and the zenith angle distribution does not fit with the expected one.
Assuming neutrino oscillations, both measurements suggest maximum mixing and
Dm2 of a few times 10-3 eV2. The other samples are due to the internally
produced events and to upward-going stopping muons. These data show a regular
deficit of observed events in each angular bin, as expected assuming neutrino
oscillations with maximum mixing, in agreement with the analysis of the
upward-throughgoing muon sample.Comment: 7 pages 6 figures to appear in the proceedings of XVIII International
Conference on Neutrino Physics and Astrophysics (Neutrino'98), Takayama,
Japan 4-9 June, 199
New MACRO results on atmospheric neutrino oscillations
The final results of the MACRO experiment on atmospheric neutrino
oscillations are presented and discussed. The data concern different event
topologies with average neutrino energies of ~3 and ~50 GeV. Multiple Coulomb
Scattering of the high energy muons in absorbers was used to estimate the
neutrino energy of each event. The angular distributions, the L/E_nu
distribution, the particle ratios and the absolute fluxes all favour nu_mu -->
nu_tau oscillations with maximal mixing and Delta m^2 =0.0023 eV^2. A
discussion is made on the Monte Carlos used for the atmospheric neutrino flux.
Some results on neutrino astrophysics are also briefly discussed.Comment: Invited Paper at the NANP03 Int. Conf., Dubna, 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
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