A
bstract
In this paper we revisit the idea of measuring the magnetic dipole moments of the charm baryons and, in particular, of
Λ
c
+
by studying the spin precession induced by the strong effective ...magnetic field inside the channels of a bent crystal. We present a detailed sensitivity study showing the feasibility of such an experiment at the LHC in the coming years.
The HPHT diamond Schottky diode was assembled as a Metal/Intrinsic/p-doped structure betavoltaic cell (BC) with a very thin (1 μm) drift layer and tested under 5–30 keV electron beam irradiation ...using a scanning electron microscope (SEM). The effect of the β-radiation energy and the backscattering of electrons on the energy conversion was studied. From the results obtained, it is shown that, the efficiency of the investigated BC increases from 1.01 to 3.75% with the decrease of β-particle energy from 30 to 5 keV due to an increase of the electron beam absorption in a thin drift layer. Maximum efficiency is achieved when the electron beam energy is close to the average β-decay energy of 3H. The BC maximum output power of the 1.6 μW was obtained at an electron beam energy of 15 keV, that matches the β-decay energy of 63Ni. The total BC conversion efficiency at 15 keV electron-beam energy is about 3%. The calculations indicated that a preferable β-source for the diamond based BCs with a thin (1 μm) drift layer is 63Ni.
•The total conversion efficiency (TCE) of the diamond cell with a thin drift layer increases while the beam energy decrease.•The most preferred beta source for the diamond Schottky diode with a thin drift layer is 63Ni.•The β-backscattered coefficient and the energy loss in the electrode significantly affects the TCE at low beam energies.•The lateral electron spread can lead to a significant loss of the output power and TCE at the edges of the drift layer.
Abstract As a prototype detector for the SHiP Surrounding Background Tagger (SBT), we constructed a cell (120 cm × 80 cm × 25 cm) made from corten steel that is filled with liquid scintillator (LS) ...composed of linear alkylbenzene (LAB) and 2,5-diphenyloxazole (PPO). The detector is equipped with two Wavelength-shifting Optical Modules (WOMs) for light collection of the primary scintillation photons. Each WOM consists of an acrylic tube that is dip-coated with a wavelength-shifting layer on its surface. Via internal total reflection, the secondary photons emitted by the molecules of the wavelength shifter are guided to a ring-shaped array of 40 silicon photomultipliers (SiPMs) coupled to the WOM for light detection. The granularity of these SiPM arrays provides an innovative method to gain spatial information on the particle crossing point. Several improvements in the detector design significantly increased the light yield with respect to earlier proof-of-principle detectors. We report on the performance of this prototype detector during an exposure to high-energy positrons at the DESY II test beam facility by measuring the collected integrated yield and the signal time-of-arrival in each of the SiPM arrays. The resulting detection efficiency and reconstructed energy deposition of the incident positrons are presented, as well as the spatial and time resolution of the detector. These results are then compared to Monte Carlo simulations.
Characterisation of the fused silica surface quality with a β-source Natochii, A.; Burmistrov, L.; Addesa, F. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2018, Letnik:
910
Journal Article
Recenzirano
Odprti dostop
A method to characterise the quality of a fused silica surface using a β-source is presented. Two fused silica bars (5×10×400mm3) were fabricated for the Cherenkov detector for proton Flux ...Measurement installed at vacuum chamber of the Super Proton Synchrotron at CERN. The resolution of such device is defined by the collection efficiency of the Cherenkov light, which is produced by relativistic charged particles in the fused silica. Thus, the surface quality of the radiator should be as good as possible to avoid light losses. The method is based on the scanning of the radiator surface with a 90Sr radioactive source and measurements of the Cherenkov light rate, detected by a PMT attached to the quartz bars. The data have been compared with a Monte-Carlo simulation, providing an estimation of the radiator’s probability of the total internal reflection and inefficient area at the edges of the bars.
In this paper we present Monte Carlo N-Particle (MCNP) simulations of the system for underwater threat detection using neutron activation analysis developed in the SABAT project. The simulated system ...is based on a D-T neutron generator emitting 14 MeV neutrons without associated α particle detection and equipped with a LaBr3:Ce scintillation detector offering superior energy resolution and allowing for precise identification of activation γ quanta. The performed simulations show that using the neutron activation analysis method with the designed geometry we are able to identify γ-rays from hydrogen, carbon, sulphur and chlorine originating from mustard gas in a sea water environment. Our results show that the most efficient way of mustard gas detection is to compare the integral peak ratio for Cl and H.
.
The problem of the transition radiation generated by a relativistic electron, which has a nonequilibrium electromagnetic field around it, at its impinging upon a conducting plate is considered. The ...peculiarities of radiation by a sufficiently low-energy “half-bare” electron at its oblique incidence on the plate are investigated. It is shown that in the considered energy range it is possible to observe certain radiation properties which come out of sight at much higher energies. It is proposed to investigate experimentally such properties for the incident electrons at several MeV energies.
Abstract
We measured the surface tension of linear alkylbenzene (LAB)
HYBLENE 113 mixed with Diphenyloxazole (PPO) as well as of pure LAB
HYBLENE 113 as part of material studies for the ...liquid-scintillator
based surround background tagger (SBT) in the proposed SHiP
experiment. The measurement was performed using the iron wire method
and the surface tension for linear alkyl benzene HYBLENE 113 plus
PPO was found to be (30.0 ± 0.6) mN/m 22.0 ± 0.5°C and
for pure HYBLENE 113, (29.2 ± 0.6) mN/m at
21.0 ± 0.5°C.
Results of simulation and measurements on the LEETECH facility with quartz Cherenkov detector prototype which is one of the candidates for the time-of-flight technique implementation at the upgraded ...BES-III and HIEPA (China) experiments are presented. The dependence of the electrons time variation from opening of the collimators is determined. The results of the dependence of time registration of Cherenkov exposure from spatial displacement of the quartz bar with the size 20 ⨯ 40 ⨯ 200 mm are presented. Time resolution of 50 ps was measured during the experiment. The obtained results are in agreement with the expected and demonstrate the possibility of the application of quartz detectors of this type for determining the kinds of the particles.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In this paper, we present experimental and numerical studies of the calibration of low-multiplicity electron source using signals from electrons incident on a diamond detector. The experiments were ...performed at the newly commissioned versatile LEETECH platform at the PHIL photoinjector facility at LAL. We show that with a single crystal CVD diamonds of 500 micrometers thickness, the energy losses from the first three electrons of 2.5-3 MeV are clearly resolved. The described technique can be used as a complementary approach for calibration of diamond detectors as well as for diagnostics of accelerated beam halos in a regime down to a few particles.
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