6,336 research outputs found
On particle production for high energy neutrino beams
Analytical formulae for the calculation of secondary particle yields in p-A
interactions are given. These formulae can be of great practical importance for
fast calculations of neutrino fluxes and for designing new neutrino beam-lines.
The formulae are based on a parameterization of the inclusive invariant cross
sections for secondary particle production measured in p-Be interactions. Data
collected in different energy ranges and kinematic regions are used. The
accuracy of the fit to the data with the empirical formulae adopted is within
the experimental uncertainties. Prescriptions to extrapolate this
parameterization to finite targets and to targets of different materials are
given. The results obtained are then used as an input for the simulation of
neutrino beams. We show that our approach describes well the main
characteristics of measured neutrino spectra at CERN. Thus it may be used in
fast simulations aiming at the optimisation of the proposed long-baseline
neutrino beams at CERN and FNAL. In particular we will show our predictions for
the CNGS beam from CERN to Gran Sasso.Comment: 18 pages, 10 figures. Submitted to The European Physics Journal
Prospects of measuring and the sign of with a massive magnetized detector for atmospheric neutrinos
The pattern of oscillation parameters emerging from current experimental data
can be further elucidated by the observation of matter effects. In contrast to
planned experiments with conventional neutrino beams, atmospheric neutrinos
offer the possibility to search for Earth-induced matter effects with very long
baselines. Resonant matter effects are asymmetric on neutrinos and
anti-neutrinos, depending on the sign of . In a three-generation
oscillation scenario, this gives access to the mass hierarchy of neutrinos,
while the size of the asymmetry would measure the admixture of electron
neutrinos to muon/tau neutrino oscillations (the mixing angle ).
The sensitivity to these effects is discussed after the detailed simulation of
a realistic experiment based on a massive detector for atmospheric neutrinos
with charge identification. We show how a detector, which measure and
distinguish between and charged current events, might
be sensitive to matter effects using atmospheric neutrinos, provided the mixing
angle is large enough.Comment: (8 pages, 8 figures, submitted to Eur.Phys.J.C
An instrument for low-level measurements of the leakage current from high-voltage biased detectors
Resistive Plates Chambers (RPC) are detectors biased at High-Voltage (HV) in excess of 4 kV. When fired by a particle, they develop a large signal current that can be read across a small resistance, 100 Omega or so. A characterization has been made of their ageing as a function of the behaviour of their leakage current with time. An array of 10 detectors has been developed for this purpose. We present the instrument designed and built to perform a continuous and automatic monitoring of the leakage current from each detector of the array, while the system is taking data. For the particular biasing set-up adopted, the current has been measured in series to the terminal connected to the HV of every channel. Since the small value of the currents, order of tens of nA, a special circuit solution and special precautions have been adopte
Neutrino hierarchy from CP-blind observables with high density magnetized detectors
High density magnetized detectors are well suited to exploit the outstanding
purity and intensities of novel neutrino sources like Neutrino Factories and
Beta Beams. They can also provide independent measurements of leptonic mixing
parameters through the observation of atmospheric muon-neutrinos. In this
paper, we discuss the combination of these observables from a multi-kton iron
detector and a high energy Beta Beam; in particular, we demonstrate that even
with moderate detector granularities the neutrino mass hierarchy can be
determined for values greater than 4.Comment: 16 pages, 7 figures. Added a new section discussing systematic errors
(sec 5.2); sec.5.1 and 4 have been extended. Version to appear in EPJ
Identifying the Neutrino mass Ordering with INO and NOvA
The relatively large value of established recently by the Daya
Bay reactor experiment opens the possibility to determine the neutrino mass
ordering with experiments currently under construction. We investigate
synergies between the NOvA long-baseline accelerator experiment with
atmospheric neutrino data from the India-based Neutrino Observatory (INO). We
identify the requirements on energy and direction reconstruction and detector
mass for INO necessary for a significant sensitivity. If neutrino energy and
direction reconstruction at the level of 10% and 10 degree can be achieved by
INO a determination of the neutrino mass ordering seems possible around 2020.Comment: 18 pages, 8 figures, minor improvements and clarifications, new panel
in fig. 7, version to appear in JHEP, typo in eq. 4 correcte
Response of microchannel plates to single particles and to electromagnetic showers
We report on the response of microchannel plates (MCPs) to single
relativistic particles and to electromagnetic showers. Particle detection by
means of secondary emission of electrons at the MCP surface has long been
proposed and is used extensively in ion time-of-flight mass spectrometers. What
has not been investigated in depth is their use to detect the ionizing
component of showers. The time resolution of MCPs exceeds anything that has
been previously used in calorimeters and, if exploited effectively, could aid
in the event reconstruction at high luminosity colliders. Several prototypes of
photodetectors with the amplification stage based on MCPs were exposed to
cosmic rays and to 491 MeV electrons at the INFN-LNF Beam-Test Facility. The
time resolution and the efficiency of the MCPs are measured as a function of
the particle multiplicity, and the results used to model the response to
high-energy showers.Comment: Paper submitted to NIM
Response of microchannel plates in ionization mode to single particles and electromagnetic showers
Hundreds of concurrent collisions per bunch crossing are expected at future
hadron colliders. Precision timing calorimetry has been advocated as a way to
mitigate the pileup effects and, thanks to their excellent time resolution,
microchannel plates (MCPs) are good candidate detectors for this goal. We
report on the response of MCPs, used as secondary emission detectors, to single
relativistic particles and to electromagnetic showers. Several prototypes, with
different geometries and characteristics, were exposed to particle beams at the
INFN-LNF Beam Test Facility and at CERN. Their time resolution and efficiency
are measured for single particles and as a function of the multiplicity of
particles. Efficiencies between 50% and 90% to single relativistic particles
are reached, and up to 100% in presence of a large number of particles. Time
resolutions between 20ps and 30ps are obtained.Comment: 20 pages, 9 figures. Paper submitted to NIM
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