CUORE: a cryogenic underground observatory for rare events Arnaboldi, C; Avignone III, F.T; Beeman, J ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2004, Letnik:
518, Številka:
3
Journal Article
Recenzirano
Odprti dostop
CUORE is a proposed tightly packed array of 1000 TeO
2 bolometers, each being a cube
5
cm
on a side with a mass of
760
g
. The array consists of 25 vertical towers, arranged in a square of 5 towers×5 ...towers, each containing 10 layers of four crystals. The design of the detector is optimized for ultralow-background searches: for neutrinoless double-beta decay of
130
Te
(33.8% abundance), cold dark matter, solar axions, and rare nuclear decays. A preliminary experiment involving 20 crystals
3×3×6
cm
3
of
340
g
has been completed, and a single CUORE tower is being constructed as a smaller-scale experiment called CUORICINO. The expected performance and sensitivity, based on Monte Carlo simulations and extrapolations of present results, are reported.
Initial performance of the CUORE-0 experiment Artusa, D. R.; Avignone, F. T.; Azzolini, O. ...
The European physical journal. C, Particles and fields,
08/2014, Letnik:
74, Številka:
8
Journal Article
Recenzirano
Odprti dostop
CUORE-0 is a cryogenic detector that uses an array of tellurium dioxide bolometers to search for neutrinoless double-beta decay of
130
Te
. We present the first data analysis with
7.1
kg
·
y
of total
...TeO
2
exposure focusing on background measurements and energy resolution. The background rates in the neutrinoless double-beta decay region of interest (2.47 to
2.57
MeV
) and in the
α
background-dominated region (2.70 to
3.90
MeV
) have been measured to be
0.071
±
0.011
and
0.019
±
0.002
counts
/
(
keV
·
kg
·
y
)
, respectively. The latter result represents a factor of 6 improvement from a predecessor experiment, Cuoricino. The results verify our understanding of the background sources in CUORE-0, which is the basis of extrapolations to the full CUORE detector. The obtained energy resolution (full width at half maximum) in the region of interest is
5.7
keV
. Based on the measured background rate and energy resolution in the region of interest, CUORE-0 half-life sensitivity is expected to surpass the observed lower bound of Cuoricino with one year of live time.
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 10−7- 10−8 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.
The
Majorana Collaboration is building the
Majorana Demonstrator, a 60
kg array of high purity germanium detectors housed in an ultra-low background shield at the Sanford Underground Laboratory in ...Lead, SD. The
Majorana Demonstrator will search for neutrinoless double-beta decay of
76Ge while demonstrating the feasibility of a tonne-scale experiment. It may also carry out a dark matter search in the 1–10
GeV/
c
2 mass range. We have found that customized Broad Energy Germanium (BEGe) detectors produced by Canberra have several desirable features for a neutrinoless double-beta decay experiment, including low electronic noise, excellent pulse shape analysis capabilities, and simple fabrication. We have deployed a customized BEGe, the
Majorana Low-Background BEGe at Kimballton (MALBEK), in a low-background cryostat and shield at the Kimballton Underground Research Facility in Virginia. This paper will focus on the detector characteristics and measurements that can be performed with such a radiation detector in a low-background environment.
► Measurement of radioactive contaminations of TeO2 crystals for the CUORE experiment. ► Both bulk and surface contamination from 238U and 232Th decay chains is not found. ► The upper limits are ...calculated to be within the contract specification. ► An extrapolation to CUORE background from bulk and surface contamination is performed.
The CUORE Crystal Validation Runs (CCVRs) have been carried out since the end of 2008 at the Gran Sasso National Laboratories, in order to test the performance and the radiopurity of the TeO2 crystals produced at SICCAS (Shanghai Institute of Ceramics, Chinese Academy of Sciences) for the CUORE experiment. In this work the results of the first 5 validation runs are presented. Results have been obtained for bulk contaminations and surface contaminations from several nuclides. An extrapolation to the CUORE background has been performed.
Superconductivity Poole, Charles P., Jr; Farach, Horacio A; Creswick, Richard J ...
2007, 2010-07-20
eBook
Superconductivity, 2E is an encyclopedic treatment of all aspects of the subject, from classic materials to fullerenes. Emphasis is on balanced coverage, with a comprehensive reference list and ...significant graphicsfrom all areas of the published literature. Widely used theoretical approaches are explained in detail. Topics of special interest include high temperature superconductors, spectroscopy, critical states, transport properties, and tunneling.This book covers the whole field of superconductivity from both the theoretical and the experimental point of view.
- Comprehensive coverage of the field of superconductivity- Very up-to date on magnetic properties, fluxons, anisotropies, etc.- Over 2500 references to the literature - Long lists of data on the various types of superconductors
The MAJORANA Project Elliott, S R; Aalseth, C E; Akashi-Ronquest, M ...
Journal of physics. Conference series,
06/2009, Letnik:
173, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Building a Ovββ experiment with the ability to probe neutrino mass in the inverted hierarchy region requires the combination of a large detector mass sensitive to Ovββ, on the order of 1-tonne, and ...unprecedented background levels, on the order of or less than 1 count per year in the Ovβ β signal region. The MAJORANA Collaboration proposes a design based on using high-purity enriched 76Ge crystals deployed in ultralow background electroformed Cu cryostats and using modern analysis techniques that should be capable of reaching the required sensitivity while also being scalable to a 1-tonne size. To demonstrate feasibility, the collaboration plans to construct a prototype system, the MAJORANA DEMONSTRATOR, consisting of 30 kg of 86% enriched 76Ge detectors and 30 kg of natural or isotope-76-depleted Ge detectors. We plan to deploy and evaluate two different Ge detector technologies, one based on a p-type configuration and the other on n-type.
The MAJORANA Project Aalseth, C E; Amman, M; Amsbaugh, J F ...
Journal of physics. Conference series,
01/2010, Letnik:
203, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The MAJORANA Project, a neutrinoless double-beta decay experiment is described with an emphasis on the choice of Ge-detector configuration.
We report the final result of the CUORICINO experiment. Operated between 2003 and 2008, with a total exposure of 19.75 kg*y of Te, CUORICINO was able to set a lower bound on the Te Ovββhalf-life of ...2.8 ×10years at 90% C.L. The limit here reported includes the effects of systematic uncertainties that are examined in detail in the paper. The corresponding upper bound on the neutrino Majorana mass is in the range 300-710 meV, depending on the adopted nuclear matrix element evaluation.
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