In this paper we consider a Beta Beam setup that tries to leverage at most existing European facilities: i.e. a setup that takes advantage of facilities at CERN to boost high-
Q
ions (
8
Li and
8
B) ...aiming at a far detector located at
L
=732 km in the Gran Sasso Underground Laboratory. The average neutrino energy for
8
Li and
8
B ions boosted at
γ
∼100 is in the range
E
ν
∈1,2 GeV, high enough to use a large iron detector of the MINOS type at the far site. We perform, then, a study of the neutrino and antineutrino fluxes needed to measure a CP-violating phase
δ
in a significant part of the parameter space. In particular, for
θ
13
≥3°, if an antineutrino flux of 3×10
19
useful
8
Li decays per year is achievable, we find that
δ
can be measured in 60% of the parameter space with 3×10
18
useful
8
B decays per year.
XEMIS: A liquid xenon detector for medical imaging Gallego Manzano, L.; Bassetto, S.; Beaupere, N. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
07/2015, Letnik:
787
Journal Article
Recenzirano
A new medical imaging technique based on the precise 3D location of a radioactive source by the simultaneous detection of 3 gamma rays has been proposed by Subatech laboratory. To take advantage of ...this novel technique a detection device based on a liquid xenon Compton telescope and a specific (beta(+), gamma) emitter radionuclide, Sc-44, are required. A first prototype of a liquid xenon time projection chamber called XEMIS1 has been successfully developed showing very promising results for the energy and spatial resolutions for the ionization signal in liquid xenon, thanks to an advanced cryogenics system, which has contributed to a high liquid xenon purity with a very good stability and an ultra-low noise front-end electronics (below 100 electrons) operating at liquid xenon temperature. The very positive results obtained with XEMIS1 have led to the development of a second prototype for small animal imaging. XEMIS2, which is now under development. To study the feasibility of the 3 gamma imaging technique and optimize the characteristics of the device, a complete Monte Carlo simulation has been also carried out. A preliminary study shows very positive results for the sensitivity, energy and spatial resolutions of XEMIS2. (C) 2014 Elsevier B.V. All rights reserved.
We report results from searches for new physics with low-energy electronic recoil data recorded with the XENON1T detector. With an exposure of 0.65 tonne-years and an unprecedentedly low background ...rate of 76 ± 2stat events/(tonne × year × keVÞ between 1 and 30 keV, the data enable one of the most sensitive searches for solar axions, an enhanced neutrino magnetic moment using solar neutrinos, and bosonic dark matter. An excess over known backgrounds is observed at low energies and most prominent between 2 and 3 keV. The solar axion model has a 3.4σ significance, and a three-dimensional 90% confidence surface is reported for axion couplings to electrons, photons, and nucleons. This surface is inscribed in the cuboid defined by gae < 3.8 × 10−12, ..., and gaegaγ < 7.7 × 10−22 GeV−1, and excludes either gae = 0 or ... . The neutrino magnetic moment signal is similarly favored over background at 3.2σ, and a confidence interval of μν ∈ (1.4, 2.9) × 10−11 μB (90% C.L.) is reported. Both results are in strong tension with stellar constraints. The excess can also be explained by β decays of tritium at 3.2σ significance with a corresponding tritium concentration in xenon of (6.2 ± 2.0) × 10−25 mol/mol. Such a trace amount can neither be confirmed nor excluded with current knowledge of its production and reduction mechanisms. The significances of the solar axion and neutrino magnetic moment hypotheses are decreased to 2.0σ and 0.9σ, respectively, if an unconstrained tritium component is included in the fitting. With respect to bosonic dark matter, the excess favors a monoenergetic peak at (2.3 ± 0.2) keV (68% C.L.) with a 3.0σ global (4.0σ local) significance over background. This analysis sets the most restrictive direct constraints to date on pseudoscalar and vector bosonic dark matter for most masses between 1 and 210 keV/c2. We also consider the possibility that 37Ar may be present in the detector, yielding a 2.82 keV peak from electron capture. Contrary to tritium, the 37Ar concentration can be tightly constrained and is found to be negligible. (ProQuest: ... denotes formula omitted.)
The beta beam CERN design is based on the present LHC injection complex and its physics reach is mainly limited by the maximum rigidity of the SPS. In fact, some of the scenarios for the machine ...upgrades of the LHC, particularly the construction of a fast cycling 1 TeV injector (“Super-SPS”), are very synergic with the construction of a higher γ beta beam. At the energies that can be reached by this machine, we demonstrate that dense calorimeters can already be used for the detection of ν at the far location. Even at moderate masses (40 kton) as the ones imposed by the use of existing underground halls at Gran Sasso, the CP reach is very large for any value of θ13 that would provide evidence of νe appearance at T2K or NOνA (θ13≥3°). Exploitation of matter effects at the CERN to Gran Sasso distance provides sensitivity to the neutrino mass hierarchy in significant areas of the θ13-δ plane.
A liquid xenon TPC for a medical imaging Compton telescope Oger, T.; Chen, W.-T.; Cussonneau, J.-P. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2012, Letnik:
695
Journal Article
Recenzirano
Odprti dostop
A new technique for medical imaging, “3γ imaging”, is studied by our group at SUBATECH for few years. A small liquid xenon time projection chamber prototype has been built in order to demonstrate the ...feasibility of this technique. With an ultra-low-noise front-end electronics, the energy deposit and resolution of 511keV γ-ray as a function of drift electric field (E) is measured with high precision. 500μm of z resolution is estimated by measuring the charge carriers drift velocity and time resolution.
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-kT 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 θ
13
values greater than 4°.
The use of nuclear emulsions in very large physics experiments is now possible thanks to the recent improvements in the industrial production of emulsions and to the development of fast automated ...microscopes. In this paper the hardware performances of the
European Scanning System (ESS) are described. The ESS is a very fast automatic system developed for the mass scanning of the emulsions of the OPERA experiment, which requires microscopes with scanning speeds of
∼
20
cm
2
/
h
in an emulsion volume of
44
μ
m
thickness.
The low-background, VUV-sensitive 3-inch diameter photomultiplier tube R11410 has been developed by Hamamatsu for dark matter direct detection experiments using liquid xenon as the target material. ...We present the results from the joint effort between the XENON collaboration and the Hamamatsu company to produce a highly radio-pure photosensor (version R11410-21) for the XENON1T dark matter experiment. After introducing the photosensor and its components, we show the methods and results of the radioactive contamination measurements of the individual materials employed in the photomultiplier production. We then discuss the adopted strategies to reduce the radioactivity of the various PMT versions. Finally, we detail the results from screening 286 tubes with ultra-low background germanium detectors, as well as their implications for the expected electronic and nuclear recoil background of the XENON1T experiment.
The DARWIN observatory is a proposed next-generation experiment to search for particle dark matter and for the neutrinoless double beta decay of
136
Xe. Out of its 50 t total natural xenon inventory, ...40 t will be the active target of a time projection chamber which thus contains about 3.6 t of
136
Xe. Here, we show that its projected half-life sensitivity is
2.4
×
10
27
year
, using a fiducial volume of 5 t of natural xenon and 10 year of operation with a background rate of less than 0.2 events/(t
·
year) in the energy region of interest. This sensitivity is based on a detailed Monte Carlo simulation study of the background and event topologies in the large, homogeneous target. DARWIN will be comparable in its science reach to dedicated double beta decay experiments using xenon enriched in
136
Xe.
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