23,702 research outputs found
A flexible scintillation light apparatus for rare event searches
Compelling experimental evidences of neutrino oscillations and their
implication that neutrinos are massive particles have given neutrinoless double
beta decay a central role in astroparticle physics. In fact, the discovery of
this elusive decay would be a major breakthrough, unveiling that neutrino and
antineutrino are the same particle and that the lepton number is not conserved.
It would also impact our efforts to establish the absolute neutrino mass scale
and, ultimately, understand elementary particle interaction unification. All
current experimental programs to search for neutrinoless double beta decay are
facing with the technical and financial challenge of increasing the
experimental mass while maintaining incredibly low levels of spurious
background. The new concept described in this paper could be the answer which
combines all the features of an ideal experiment: energy resolution, low cost
mass scalability, isotope choice flexibility and many powerful handles to make
the background negligible. The proposed technology is based on the use of
arrays of silicon detectors cooled to 120 K to optimize the collection of the
scintillation light emitted by ultra-pure crystals. It is shown that with a 54
kg array of natural CaMoO4 scintillation detectors of this type it is possible
to yield a competitive sensitivity on the half-life of the neutrinoless double
beta decay of 100Mo as high as ~10E24 years in only one year of data taking.
The same array made of 40CaMoO4 scintillation detectors (to get rid of the
continuous background coming from the two neutrino double beta decay of 48Ca)
will instead be capable of achieving the remarkable sensitivity of ~10E25 years
on the half-life of 100Mo neutrinoless double beta decay in only one year of
measurement.Comment: 12 pages, 4 figures. Prepared for submission to EPJ
Pulse-Shape discrimination with the Counting Test Facility
Pulse shape discrimination (PSD) is one of the most distinctive features of
liquid scintillators. Since the introduction of the scintillation techniques in
the field of particle detection, many studies have been carried out to
characterize intrinsic properties of the most common liquid scintillator
mixtures in this respect. Several application methods and algorithms able to
achieve optimum discrimination performances have been developed. However, the
vast majority of these studies have been performed on samples of small
dimensions. The Counting Test Facility, prototype of the solar neutrino
experiment Borexino, as a 4 ton spherical scintillation detector immersed in
1000 tons of shielding water, represents a unique opportunity to extend the
small-sample PSD studies to a large-volume setup. Specifically, in this work we
consider two different liquid scintillation mixtures employed in CTF,
illustrating for both the PSD characterization results obtained either with the
processing of the scintillation waveform through the optimum Gatti's method, or
via a more conventional approach based on the charge content of the
scintillation tail. The outcomes of this study, while interesting per se, are
also of paramount importance in view of the expected Borexino detector
performances, where PSD will be an essential tool in the framework of the
background rejection strategy needed to achieve the required sensitivity to the
solar neutrino signals.Comment: 39 pages, 17 figures, submitted to Nucl. Instr. Meth.
New Evidence on Gender Difference in Promotion Rates: An Empirical Analysis of a Sample of New Hires
Using a large sample of establishments drawn from the Multi-City Study of Urban Inequality (MCSUI) employer survey, we study gender differences in promotion rates and in the wage gains attached to promotions. Several unique features of our data distinguish our analysis from the previous literature on this topic. First, we have information on the wage increases attached to promotions, and relatively few studies on gender differences have considered promotions and wage increases together. Second, our data include job-specific worker performance ratings, allowing us to control for performance and ability more precisely than through commonly-used skill indicators such as educational attainment or tenure. Third, in addition to standard information on occupation and industry, we have data on a number of other firm characteristics, enabling us to control for these variables while still relying on a broad, representative sample, as opposed to a single firm or a similarly narrowly-defined population. Our results indicate that women have lower probabilities of promotion and expected promotion than do men but that there is essentially no gender difference in wage growth with or without promotions.
Beyond Higgs Couplings: Probing the Higgs with Angular Observables at Future Colliders
We study angular observables in the channel at future circular colliders such as CEPC
and FCC-ee. Taking into account the impact of realistic cut acceptance and
detector effects, we forecast the precision of six angular asymmetries at CEPC
(FCC-ee) with center-of-mass energy 240 GeV and 5 (30) integrated luminosity. We then determine the projected sensitivity to
a range of operators relevant for the Higgs-strahlung process in the
dimension-6 Higgs EFT. Our results show that angular observables provide
complementary sensitivity to rate measurements when constraining various tensor
structures arising from new physics. We further find that angular asymmetries
provide a novel means of both probing BSM corrections to the
coupling and constraining the "blind spot" in indirect limits on supersymmetric
scalar top partners.Comment: 28 pages, 9 figures. v2: references added, matches published version
in JHE
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