Abstract
Systematic uncertainties in accelerator oscillation neutrino
experiments arise from nuclear models describing neutrino-nucleus
interactions. To mitigate these uncertainties, we can study
...neutrino-nuclei interactions with detectors possessing enhanced
hadron detection capabilities at energies below the nuclear Fermi
level. Gaseous detectors not only lower the particle detection
threshold but also enable the investigation of nuclear effects on
various nuclei by allowing for changes in the gas composition. This
approach provides valuable insights into the modelling of
neutrino-nucleus interactions and significantly reduces associated
uncertainties. Here, we discuss the design and first operation of a
gaseous argon time projection chamber optically read. The detector
operates at atmospheric pressure and features a single stage of
electron amplification based on a thick GEM. Here, photons are
produced with wavelengths in the vacuum ultraviolet regime. In an
optical detector, the primary constraint is the light yield. This
study explores the possibility of increasing the light by applying a
low electric field downstream of the ThGEM. In this region, called
the electroluminescence gap, electrons propagate and excite the
argon atoms, leading to the subsequent emission of photons. This
process occurs without any further electron amplification, and it is
demonstrated that the total light yield increases up to three times
by applying moderate electric fields of the order of
3 kV/cm. Finally, an indirect method is discussed for determining
the photon yield/charge gain of a ThGEM, giving a value of
18.3 photons detected per secondary electron.
Polysiloxane-based scintillators for shashlik calorimeters Acerbi, F.; Branca, A.; Brizzolari, C. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
03/2020, Letnik:
956
Journal Article
Recenzirano
Odprti dostop
We present the first application of polysiloxane-based scintillators as active medium in a shashlik sampling calorimeter. These results were obtained from a testbeam campaign of a ∼6×6×45 cm3 (13 X0 ...depth) prototype. A Wavelength Shifting fiber array of 36 elements runs perpendicularly to the stack of iron (15 mm) and polysiloxane scintillator (15 mm) tiles with a density of about one over cm2. Unlike shashlik calorimeters based on plastic organic scintillators, here fibers are optically matched with the scintillator without any intermediate air gap. The prototype features a compact light readout based on Silicon Photo-Multipliers embedded in the bulk of the detector. The detector was tested with electrons, pions and muons with energies ranging from 1 to 7 GeV at the CERN-PS. This solution offers a highly radiation hard detector to instrument the decay region of a neutrino beam, providing an event-by-event measurement of high-angle decay products associated with neutrino production (ENUBET, Enhanced NeUtrino BEams from kaon Tagging, ERC project). The results in terms of light yield, uniformity and energy resolution, are compared to a similar calorimeter built with ordinary plastic scintillators.
Neutrino neutral-current (NC) induced single photon production is a sub-leading order process for accelerator-based neutrino beam experiments including T2K. It is, however, an important process to ...understand because it is a background for electron (anti)neutrino appearance oscillation experiments. Here, we performed the first search of this process below 1 GeV using the fine-grained detector at the T2K ND280 off-axis near detector. By reconstructing single photon kinematics from electron-positron pairs, we achieved 95% pure gamma ray sample from 5.738 × 10 20 protons-on-targets neutrino mode data. We do not find positive evidence of NC induced single photon production in this sample. We set the model-dependent upper limit on the cross-section for this process, at 0.114 × 10 − 38 cm2 (90% C.L.) per nucleon, using the J-PARC off-axis neutrino beam with an average energy of E ∼ 0.6 GeV. This is the first limit on this process below 1 GeV which is important for current and future oscillation experiments looking for electron neutrino appearance oscillation signals.
An iron- plastic-scintillator shashlik calorimeter with a 4.3 X0 longitudinal segmentation was tested in November 2016 at the CERN East Area facility with charged particles up to 5 GeV . The ...performance of this detector in terms of electron energy resolution, linearity, response to muons and hadron showers are presented in this paper and compared with simulation. Such a fine-grained longitudinal segmentation is achieved using a very compact light readout system developed by the SCENTT and ENUBET Collaborations, which is based on fiber-SiPM coupling boards embedded in the bulk of the detector. We demonstrate that this system fulfills the requirements for neutrino physics applications and discuss performance and additional improvements.
Silicon Photomultipliers with cell-pitch ranging from 12 μm to 20 μm were tested against neutron irradiation at moderate fluences to study their performance for calorimetric applications. The ...photosensors were developed by FBK employing the RGB-HD technology. We performed irradiation tests up to 2×1011 n/cm2 (1 MeV eq.) at the INFN-LNL Irradiation Test facility. The SiPMs were characterized on-site (dark current and photoelectron response) during and after irradiations at different fluences. The irradiated SiPMs were installed in the ENUBET compact calorimetric modules and characterized with muons and electrons at the CERN East Area facility. The tests demonstrate that both the electromagnetic response and the sensitivity to minimum ionizing particles are retained after irradiation. Gain compensation can be achieved increasing the bias voltage well within the operation range of the SiPMs. The sensitivity to single photoelectrons is lost at ∼1010 n/cm2 due to the increase of the dark current.
Precise knowledge of the beam optics at the LHC is crucial to fulfill the physics goals of the TOTEM experiment, where the kinematics of the scattered protons is reconstructed with near-beam ...telescopes-so-called Roman pots (RP). Before being detected, the protons' trajectories are influenced by the magnetic fields of the accelerator lattice. Thus precise understanding of the proton transport is of key importance for the experiment. A novel method of optics evaluation is proposed which exploits kinematical distributions of elastically scattered protons observed in the RPs. Theoretical predictions, as well as Monte Carlo studies, show that the residual uncertainty of the optics estimation method is smaller than .
Hadron production (HARP) is a high-statistics, full solid angle experiment to measure hadron production using proton and pion beams with momenta between 3 and 15 GeV/c impinging on many solid and ...liquid targets. Due to the experimental requirements, the time projection chamber (TPC) has been designed to provide full solid-angle acceptance and to be able to sustain a high event rate. The calibration strategy is based on the redundancy of a large spectrum of characterization methods. The specificity of the HARP TPC design, the calibration methods and results, and the present knowledge of detector performances will be reported
The main goals of the TOTEM Experiment at the LHC are the measurements of the elastic and total p-p cross sections and the studies of the diffractive dissociation processes. At LHC, collisions are ...produced at a rate of 40 MHz, imposing strong requirements for the Data Acquisition Systems (DAQ) in terms of trigger rate and data throughput. The VME based Front End Driver (FED) modules, host mezzanines that receive data through optical fibres directly from the detectors. In order to get rid of the VME bottleneck and improve scalability and the overall capabilities of the DAQ, a new system was designed and constructed based on the Scalable Readout System (SRS), developed in the framework of the RD51 Collaboration. The project aims to increase the efficiency of the actual readout system providing higher bandwidth, and increasing data filtering, implementing a second-level trigger event selection based on hardware pattern recognition algorithms. The obtained results and the perspectives of the project are reported.
Results from the HARP experiment Radicioni, E
Journal of physics. Conference series,
07/2008, Letnik:
120, Številka:
5
Journal Article
Recenzirano
Odprti dostop
Hadron production is a key ingredient for precise prediction of atmospheric ν fluxes, characterization of accelerator ν beams, and quantification of π production and capture for ν-factory designs. ...HARP at the CERN PS was the first hadron production experiment designed on purpose to match all these requirements. We briefly describe here its most recent results.
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