The TORIO-229 experiment aims for a direct model-independent determination of the transition energy of
229
m
Th produced in
233
U alpha decay. This knowledge will be of interest for the development ...of a scientific clock exploiting the thorium isomeric state, which would be able to significantly surpass the precision of the presently best clocks. As a detector for the isomeric transition, it is planned to use an array of fast transition-edge sensors (TESs) which demonstrated to be feasible in our previous work where the Ir/Au TES prototype demonstrated
4.6
±
1.7
µs rise time,
5.8
±
2.1
µs fall time and
0.789
±
0.023
eV energy resolution and signal-to-noise ratio of
∼
10 with one-photon (2.824 eV) signal, satisfying the experimental requirements. Such a microcalorimeter will allow to register the transition in every possible channel in the energy range from 3 to 50 eV and with a lifetime of > 5 µs. To have a full characterization of a single TES for the final detector array design, its thermal conductance has to be measured. In this contribution, we report on a test measurement of thermal coupling of a TORIO-229 prototype-like iridium-gold TES.
Abstract
After its successful campaign of measurements beyond the Polar Arctic Circle, the PolarquEEEst experiment measured the cosmic charged particle rate at sea level in a latitude interval ...between 35
$$^{\circ }$$
∘
N and 82
$$^{\circ }$$
∘
N. In this paper, these measurements are described and the corresponding results are discussed.
The eruption of the Hunga-Tonga volcano in the South Pacific Ocean on January 15, 2022, at about 4:15 UTC, generated a violent explosion, which created atmospheric pressure disturbances in the form ...of Rayleigh-Lamb waves detected all over the globe. Here we discuss the observation of the Hunga-Tonga shock-wave performed at the Ny-Ålesund Research Station on the Spitsbergen island, by the detectors of the PolarquEEEst experiment and their ancillary sensors. Online pressure data as well as the results of dedicated offline analysis are presented and discussed in details. Results include wave arrival times, wave amplitude measurements and wave velocity calculation. We observed five passages of the shock wave with a significance larger than 3 Formula: see text and an amplitude up to 1 hPa. The average propagation velocity resulted to be (308 ± 0.6) m/s. Possible effects of the atmospheric pressure variation associated with the shock-wave multiple passages on the cosmic-ray rate at ground level are also investigated. We did not find any significant evidence of this effect.
This paper describes the simulation framework of the extreme energy events (EEE) experiment. EEE is a network of cosmic muon trackers, each made of three multi-gap resistive plate chambers (MRPC), ...able to precisely measure the absolute muon crossing time and the muon integrated angular flux at the ground level. The response of a single MRPC and the combination of three chambers have been implemented in a GEANT4-based framework (GEMC) to study the telescope response. The detector geometry, as well as details about the surrounding materials and the location of the telescopes have been included in the simulations in order to realistically reproduce the experimental set-up of each telescope. A model based on the latest parametrization of the cosmic muon flux has been used to generate single muon events. After validating the framework by comparing simulations to selected EEE telescope data, it has been used to determine detector parameters not accessible by analysing experimental data only, such as detection efficiency, angular and spatial resolution.
We propose and discuss the development of a new photo-detector to be employed in underwater neutrino detectors where large detection area and good background suppression are required. The design ...includes a position-sensitive hemispherical photomultiplier coupled to a direction-sensitive light-guide system.
Characterisation of scCVD diamond detectors with γ sources Caiffi, B.; Amapane, N.; Argirò, S. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/2014, Letnik:
754
Journal Article
Recenzirano
Odprti dostop
A single-crystal CVD (Chemical Vapor Deposition) diamond detector was used to measure γ rays in order to assess its performance in terms of energy resolution and linearity. For this purpose, 57Co, ...133Ba, 22Na, 207Bi and 137Cs γ sources were used. Electrons scattered by the backward Compton process were detected in the diamond, in coincidence with (backscattered) γs measured in a NaI detector, placed at 180° from the CVD diamond detector with respect to the source. The resulting calibration shows a linear dependence of the charge deposited in the diamond and a resolution of about 24keV FWHM for the energy of the incident γs between 40keV (57Co) and 477keV (137Cs), comparable with the resolution of our electronic chain.
In this contribution, we present the expected performance of a new detector to measure the absolute energy-integrated flux and the energy spectrum of anti-neutrinos emitted by a nuclear power plant. ...The number of detected anti-neutrino is a direct measure of the power while from the energy spectrum is possible to infer the evolution in time of the core isotopic composition. The proposed method should be sensitive to a sudden change in the core burn-up as caused, for instance, by a fraudulent subtraction of plutonium. The detector, a
130
×
100
×
100
cm
3
cube with
1
m
3
active volume, made by plastic scintillator wrapped in thin Gd foils, is segmented in 50 independent optical channels read, side by side, by a pair of 3
in. photomultipliers. Anti-neutrino interacts with hydrogen contained in the plastic scintillator via the neutron inverse
β
- decay (
ν
¯
p
→
e
+
n
). The high segmentation of the detector allows to reduce the background from other reactions by detecting independent hits for the positron, the two photons emitted in the
e
+
e
-
annihilation and the neutron.
The security of ports and transportation is of utmost importance for the development of economy and the security of a nation. Among the necessary actions to ensure the security of ports and borders, ...the inspection of containers is one of the most time consuming and expensive procedures. Potential threats are the illegal traffic of radioactive materials that could be employed for the construction of weapons, as uranium and plutonium. New techniques for the inspections of containers should be fast, allow the detection and identification of dangerous materials, and be non-invasive, to reduce costs and delays. We propose to build a large surface photon and neutron detector based on plastic scintillator to identify the presence of fissile or fertile material inside a container. The detector consists of scintillator bars, wrapped in thin foils of reflecting material containing gadolinium for neutron capture and arranged in planes separated by few-millimeter-thick lead sheets. The total instrumented surface is a few squared meters. Neutrons emitted by fissile materials are identified by gadolinium capture, which results in a high multiplicity gamma flash with total energy of 8
MeV. Photons emitted by the same source are detected via their Compton interaction in the scintillating material. The discrimination between photons and neutrons is achieved by measuring the number of bars of the detector that measured a signal above threshold. The resulting multiplicity is a clear signature of the particle type. First simulations of the detector response with GEANT4 have shown that a detection efficiency of 20–30% for neutrons emitted by fissile materials and a photon/neutron rejection ratio of more than two orders of magnitude can be achieved. Based on these simulations, the sensitivity of the detector to known amounts of plutonium and uranium was estimated. In this contribution, the conceptual design of the detector will be reviewed, the results of the simulations will be presented and the plan of measurements to be performed on a prototype will be discussed.
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