2,034 research outputs found
Radon mitigation during the installation of the CUORE decay detector
CUORE - the Cryogenic Underground Observatory for Rare Events - is an
experiment searching for the neutrinoless double-beta () decay
of Te with an array of 988 TeO crystals operated as bolometers at
10 mK in a large dilution refrigerator. With this detector, we aim for a
Te decay half-life sensitivity of y
with 5 y of live time, and a background index of
counts/keV/kg/y. Making an effort to maintain radiopurity by minimizing the
bolometers' exposure to radon gas during their installation in the cryostat, we
perform all operations inside a dedicated cleanroom environment with a
controlled radon-reduced atmosphere. In this paper, we discuss the design and
performance of the CUORE Radon Abatement System and cleanroom, as well as a
system to monitor the radon level in real time.Comment: 10 pages, 6 figures, 1 tabl
White Paper: Measuring the Neutrino Mass Hierarchy
This white paper is a condensation of a report by a committee appointed
jointly by the Nuclear Science and Physics Divisions at Lawrence Berkeley
National Laboratory (LBNL). The goal of this study was to identify the most
promising technique(s) for resolving the neutrino mass hierarchy. For the most
part, we have relied on calculations and simulations presented by the
proponents of the various experiments. We have included evaluations of the
opportunities and challenges for these experiments based on what is available
already in the literature.Comment: White paper prepared for Snowmass-201
Effects of mental health status during adolescence on primary care costs in adulthood across three British cohorts
PURPOSE: This study examines the association between mental health problems in adolescence and general practice (GP) costs during adulthood up to age 50 in the UK. METHODS: We conducted secondary analyses of three British birth cohorts (individuals born in single weeks in 1946, 1958 and 1970). Data for the three cohorts were analysed separately. All respondents who participated in the cohort studies were included. Adolescent mental health status was assessed in each cohort using the Rutter scale (or, for one cohort, a forerunner of that scale) completed in interviews with parents and teachers when cohort members were aged around 16. Presence and severity of conduct and emotional problems were modelled as independent variables in two-part regression models in which the dependent variable was costs of GP services from data collection sweeps up to mid-adulthood. All analyses were adjusted for covariates (cognitive ability, mother's education, housing tenure, father's social class and childhood physical disability). RESULTS: Adolescent conduct and emotional problems, particularly when coexisting, were associated with relatively high GP costs in adulthood up to age 50. Associations were generally stronger in females than males. CONCLUSION: Associations between adolescent mental health problems and annual GP cost were evident decades later, to age 50, suggesting that there could be significant future savings to healthcare budgets if rates of adolescent conduct and emotional problems could be reduced. TRIAL REGISTRATION: Not applicable
Closed-loop Stimulation of Temporal Cortex Rescues Functional Networks and Improves Memory
Memory failures are frustrating and often the result of ineffective encoding. One approach to improving memory outcomes is through direct modulation of brain activity with electrical stimulation. Previous efforts, however, have reported inconsistent effects when using open-loop stimulation and often target the hippocampus and medial temporal lobes. Here we use a closed-loop system to monitor and decode neural activity from direct brain recordings in humans. We apply targeted stimulation to lateral temporal cortex and report that this stimulation rescues periods of poor memory encoding. This system also improves later recall, revealing that the lateral temporal cortex is a reliable target for memory enhancement. Taken together, our results suggest that such systems may provide a therapeutic approach for treating memory dysfunction
CUORE and beyond: bolometric techniques to explore inverted neutrino mass hierarchy
The CUORE (Cryogenic Underground Observatory for Rare Events) experiment will
search for neutrinoless double beta decay of Te. With 741 kg of TeO
crystals and an excellent energy resolution of 5 keV (0.2%) at the region of
interest, CUORE will be one of the most competitive neutrinoless double beta
decay experiments on the horizon. With five years of live time, CUORE projected
neutrinoless double beta decay half-life sensitivity is y
at ( y at the 90% confidence level), which
corresponds to an upper limit on the effective Majorana mass in the range
40--100 meV (50--130 meV). Further background rejection with auxiliary light
detector can significantly improve the search sensitivity and competitiveness
of bolometric detectors to fully explore the inverted neutrino mass hierarchy
with Te and possibly other double beta decay candidate nuclei.Comment: Submitted to the Proceedings of TAUP 2013 Conferenc
CUORE-0 results and prospects for the CUORE experiment
With 741 kg of TeO2 crystals and an excellent energy resolution of 5 keV
(0.2%) at the region of interest, the CUORE (Cryogenic Underground Observatory
for Rare Events) experiment aims at searching for neutrinoless double beta
decay of 130Te with unprecedented sensitivity. Expected to start data taking in
2015, CUORE is currently in an advanced construction phase at LNGS. CUORE
projected neutrinoless double beta decay half-life sensitivity is 1.6E26 y at 1
sigma (9.5E25 y at the 90% confidence level), in five years of live time,
corresponding to an upper limit on the effective Majorana mass in the range
40-100 meV (50-130 meV). Further background rejection with auxiliary bolometric
detectors could improve CUORE sensitivity and competitiveness of bolometric
detectors towards a full analysis of the inverted neutrino mass hierarchy.
CUORE-0 was built to test and demonstrate the performance of the upcoming CUORE
experiment. It consists of a single CUORE tower (52 TeO2 bolometers of 750 g
each, arranged in a 13 floor structure) constructed strictly following CUORE
recipes both for materials and assembly procedures. An experiment its own,
CUORE-0 is expected to reach a sensitivity to the neutrinoless double beta
decay half-life of 130Te around 3E24 y in one year of live time. We present an
update of the data, corresponding to an exposure of 18.1 kg y. An analysis of
the background indicates that the CUORE performance goal is satisfied while the
sensitivity goal is within reach.Comment: 10 pages, 3 figures, to appear in the proceedings of NEUTRINO 2014,
26th International Conference on Neutrino Physics and Astrophysics, 2-7 June
2014, held at Boston, Massachusetts, US
Exploring the Neutrinoless Double Beta Decay in the Inverted Neutrino Hierarchy with Bolometric Detectors
Neutrinoless double beta decay (0nubb) is one of the most sensitive probes
for physics beyond the Standard Model, providing unique information on the
nature of neutrinos. In this paper we review the status and outlook for
bolometric 0nubb decay searches. We summarize recent advances in background
suppression demonstrated using bolometers with simultaneous readout of heat and
light signals. We simulate several configurations of a future CUORE-like
bolometer array which would utilize these improvements and present the
sensitivity reach of a hypothetical next-generation bolometric 0nubb
experiment. We demonstrate that a bolometric experiment with the isotope mass
of about 1 ton is capable of reaching the sensitivity to the effective Majorana
neutrino mass (|mee|) of order 10-20 meV, thus completely exploring the
so-called inverted neutrino mass hierarchy region. We highlight the main
challenges and identify priorities for an R&D program addressing them.Comment: 22 pages, 15 figures, submitted to EPJ
Status of the CUORE and results from the CUORE-0 neutrinoless double beta decay experiments
CUORE is a 741 kg array of TeO2 bolometers for the search of neutrinoless
double beta decay of 130Te. The detector is being constructed at the Laboratori
Nazionali del Gran Sasso, Italy, where it will start taking data in 2015. If
the target background of 0.01 counts/keV/kg/y will be reached, in five years of
data taking CUORE will have a 1 sigma half life sensitivity of 10E26 y. CUORE-0
is a smaller experiment constructed to test and demonstrate the performances
expected for CUORE. The detector is a single tower of 52 CUORE-like bolometers
that started taking data in spring 2013. The status and perspectives of CUORE
will be discussed, and the first CUORE-0 data will be presented.Comment: 7 pages, 4 figures, to be published in the proceedings of ICHEP 2014,
37th International Conference on High Energy Physics, Valencia (Spain) 2-9
July 201
Validation of techniques to mitigate copper surface contamination in CUORE
In this article we describe the background challenges for the CUORE
experiment posed by surface contamination of inert detector materials such as
copper, and present three techniques explored to mitigate these backgrounds.
Using data from a dedicated test apparatus constructed to validate and compare
these techniques we demonstrate that copper surface contamination levels better
than 10E-07 - 10E-08 Bq/cm2 are achieved for 238U and 232Th. If these levels
are reproduced in the final CUORE apparatus the projected 90% C.L. upper limit
on the number of background counts in the region of interest is 0.02-0.03
counts/keV/kg/y depending on the adopted mitigation technique.Comment: 10 pages, 6 figures, 6 table
Search for 14.4 keV solar axions from M1 transition of Fe-57 with CUORE crystals
We report the results of a search for axions from the 14.4 keV M1 transition
from Fe-57 in the core of the sun using the axio-electric effect in TeO2
bolometers. The detectors are 5x5x5 cm3 crystals operated at about 10 mK in a
facility used to test bolometers for the CUORE experiment at the Laboratori
Nazionali del Gran Sasso in Italy. An analysis of 43.65 kg d of data was made
using a newly developed low energy trigger which was optimized to reduce the
detectors energy threshold. An upper limit of 0.63 c kg-1 d-1 was established
at 95% C.L.. From this value, a lower bound at 95% C.L. was placed on the
Peccei-Quinn energy scale of fa >= 0.76 10**6 GeV for a value of S=0.55 for the
flavor-singlet axial vector matrix element. Bounds are given for the interval
0.15 < S < 0.55.Comment: 14 pages, 6 figures, submitted to JCA
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