313 research outputs found
Cryogenic silicon detectors with implanted contacts for the detection of visible photons using the Neganov-Luke Effect
There is a common need in astroparticle experiments such as direct dark
matter detection, 0{\nu}\b{eta}\b{eta} (double beta decay without emission of
neutrinos) and Coherent Neutrino Nucleus Scattering experiments for light
detectors with a very low energy threshold. By employing the Neganov-Luke
Effect, the thermal signal of particle interactions in a semiconductor absorber
operated at cryogenic temperatures, can be amplified by drifting the
photogenerated electrons and holes in an electric field. This technology is not
used in current experiments, in particular because of a reduction of the signal
amplitude with time which is due to trapping of the charges within the
absorber. We present here the first results of a novel type of Neganov-Luke
Effect detector with an electric field configuration designed to improve the
charge collection within the semiconductor.Comment: 6 pages, 5 figures, submitted to Journal of Low Temperature Physic
On the Quantitative Impact of the Schechter-Valle Theorem
We evaluate the Schechter-Valle (Black Box) theorem quantitatively by
considering the most general Lorentz invariant Lagrangian consisting of
point-like operators for neutrinoless double beta decay. It is well known that
the Black Box operators induce Majorana neutrino masses at four-loop level.
This warrants the statement that an observation of neutrinoless double beta
decay guarantees the Majorana nature of neutrinos. We calculate these
radiatively generated masses and find that they are many orders of magnitude
smaller than the observed neutrino masses and splittings. Thus, some lepton
number violating New Physics (which may at tree-level not be related to
neutrino masses) may induce Black Box operators which can explain an observed
rate of neutrinoless double beta decay. Although these operators guarantee
finite Majorana neutrino masses, the smallness of the Black Box contributions
implies that other neutrino mass terms (Dirac or Majorana) must exist. If
neutrino masses have a significant Majorana contribution then this will become
the dominant part of the Black Box operator. However, neutrinos might also be
predominantly Dirac particles, while other lepton number violating New Physics
dominates neutrinoless double beta decay. Translating an observed rate of
neutrinoless double beta decay into neutrino masses would then be completely
misleading. Although the principal statement of the Schechter-Valle theorem
remains valid, we conclude that the Black Box diagram itself generates
radiatively only mass terms which are many orders of magnitude too small to
explain neutrino masses. Therefore, other operators must give the leading
contributions to neutrino masses, which could be of Dirac or Majorana nature.Comment: 18 pages, 4 figures; v2: minor corrections, reference added, matches
journal version; v3: typo corrected, physics result and conclusions unchange
Characterization of ZnSe scintillating bolometers for Double Beta Decay
ZnSe scintillating bolometers are good candidates for future Double Beta
Decay searches, because of the 82Se high Q-value and thanks to the possibility
of alpha background rejection on the basis of the scintillation signal. In this
paper we report the characteristics and the anomalies observed in an extensive
study of these devices. Among them, an unexpected high emission from alpha
particles, accompanied with an unusual pattern of the light vs. heat scatter
plot. The perspectives for the application of this kind of detectors to search
for the Neutrinoless Double Beta Decay of 82Se are presented.Comment: 12 pages, 10 figure
Measuring social-emotional development in middle childhood: the Middle Years Development Instrument
This paper discusses the conceptualization, development, validation, and application of the Middle Years Development Instrument (MDI) – a population-based child self-report tool that assesses children\u27s social-emotional development and well-being in the context of their home, school, and neighborhood. The MDI is administered at a population-level to 4th and 7th grade students within participating public school districts across British Columbia, Canada. Children respond to items in five domains: (1) social-emotional development, (2) connectedness to peers and adults, (3) school experiences, (4) physical health and well-being, and (5) constructive use of after-school time. Results are aggregated for schools and communities and reported back in comprehensive reports and community maps to inform planning and decision making at local and regional levels. Shared testimonials exemplify how MDI results have been used by educators, community organizers, and city planners as a catalyst for promoting children\u27s social and emotional competence and facilitating collaboration between schools and communities
Precision Neutrino Oscillation Physics with an Intermediate Baseline Reactor Neutrino Experiment
We discuss the physics potential of intermediate km
baseline experiments at reactor facilities, assuming that the solar neutrino
oscillation parameters and lie in the
high-LMA solution region. We show that such an intermediate baseline reactor
experiment can determine both and with a
remarkably high precision. We perform also a detailed study of the sensitivity
of the indicated experiment to , which drives the
dominant atmospheric () oscillations, and to
- the neutrino mixing angle limited by the data from the CHOOZ and
Palo Verde experiments. We find that this experiment can improve the bounds on
. If the value of is large enough, \sin^2\theta
\gtap 0.02, the energy resolution of the detector is sufficiently good and if
the statistics is relatively high, it can determine with extremely high
precision the value of . We also explore the potential of
the intermediate baseline reactor neutrino experiment for determining the type
of the neutrino mass spectrum, which can be with normal or inverted hierarchy.
We show that the conditions under which the type of neutrino mass hierarchy can
be determined are quite challenging, but are within the reach of the experiment
under discussion.Comment: 25 page
The Main Results of the Borexino Experiment
The main physical results on the registration of solar neutrinos and the
search for rare processes obtained by the Borexino collaboration to date are
presented.Comment: 8 pages, 8 figgures, To be published as Proceedings of the Third
Annual Large Hadron Collider Physics Conference, St. Petersburg, Russia, 201
Reactor Neutrino Experiments Compared to Superbeams
We present a detailed quantitative discussion of the measurement of the
leptonic mixing angle with a future reactor neutrino
oscillation experiment consisting of a near and far detector. We perform a
thorough analysis of the impact of various systematical errors and compare the
resulting physics potential to the one of planned first-generation superbeam
experiments. Furthermore, we investigate the complementarity of both types of
experiments. We find that, under realistic assumptions, a determination of
down to is possible with reactor experiments.
They are thus highly competitive to first-generation superbeams and may be able
to test on shorter timescales. In addition, we find that
the combination of a KamLAND-size reactor experiment with one or two superbeams
could substantially improve the ability to access the neutrino mass hierarchy
or the leptonic CP phase.Comment: Typo in Eq. (9) corrected. 36 pages, 12 figure
Associations between school readiness and student wellbeing: a six-year follow up study
Published online: 06 August 2020It is well established that children’s school readiness is associated with their later academic achievement, but less is known about whether school readiness is also associated with other measures of school success, such as students’ social and emotional wellbeing. While some previous research has shown a link between early social and emotional development and student wellbeing, results are mixed and the strength of these relationships vary depending on whether data is based on child, teachers or parents ratings and which specific student wellbeing outcomes are measured. The present study explored the association between teacher-rated school readiness (Mage = 5.6 years) across five developmental domains (physical, social, emotional, language and cognitive, and communication and general knowledge) and four aspects of student wellbeing (life satisfaction, optimism, sadness and worries) in Grade 6 (Mage = 11.9 years) in a sample of 3906 Australian children. After adjustment for background child and family-level factors, children’s early physical, social and emotional development were associated with all four wellbeing outcomes in Grade 6, but early language and cognitive skills and communication and general knowledge skills were only associated with internalising behaviours (sadness and worries). Mechanisms through which these different aspects of development might influence later wellbeing are discussed, as well as ways that schools and governments can support students’ social and emotional wellbeing.T. Gregory, E. Dal Grande, M. Brushe, D. Engelhardt, S. Luddy and M. Guhn ... et al
New limits on heavy sterile neutrino mixing in -decay obtained with the Borexino detector
If heavy neutrinos with mass 2 are produced in the
Sun via the decay in a side
branch of pp-chain, they would undergo the observable decay into an electron, a
positron and a light neutrino . In the
present work Borexino data are used to set a bound on the existence of such
decays. We constrain the mixing of a heavy neutrino with mass 1.5 MeV 14 MeV to be
respectively. These are tighter limits on the mixing parameters than obtained
in previous experiments at nuclear reactors and accelerators.Comment: 7 pages, 6 figure
- …