753 research outputs found
Status of the CUORE and CUORE-0 experiments at Gran Sasso
CUORE is a 741 kg array of TeO2 bolometers for the search of
neutrinoless double beta decay in 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 half life sensitivity of ∼ 1026 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 the CUORE and
CUORE-0 experiments will be presented
Focal Cerebral Infarction in Newborn: Description of Three Cases:
We observed 3 full-term newborns with focal ischemic injury of the middle cerebral artery (MCA), in which diagnosis of MCA stroke was suspected by US and confirmed by CT scan and MRI. A four-year follow-up was carried out to study the effect of neonatal stroke on neurodevelopmental outcome. All children had a history of pre-perinatal risk factors: neonatal cerebral infarction in term infants, in fact, has many possible causes, including bacterial meningitis, inherited or acquired coagulopathies, trauma and hypoxia-ischemia. The prognosis of neonatal MCA infarction depends on early diagnosis, on the CNS plasticity mechanism and, finally, on medical therapy and neuropsychological rehabilitation
Weight management, psychological distress and binge eating in obesity. A reappraisal of the problem
The psychological effects of dieting and weight loss have been an area of controversy in obesity. As part of
a large multicenter study involving 1944 obese subjects seeking treatment at Italian medical centers, we
investigated the effects of weight loss on psychological distress and binge eating in 500 subjects
remaining in continuous treatment at different centers with slightly different strategies (78.8% females;
age: M = 46.2 years, SD = 10.8; BMI: M = 37.3 kg/m2, SD = 5.6). At baseline and after 12 months all
subjects were evaluated by the SymptomCheckList-90 Global Severity Index (SCL-GSI) and by the Binge
Eating Scale (BES). In both males and females, weight loss was associated with improved psychometric
testing. Changes in SCL-GSI were associated with changes in BMI (b = 0.13; t = 2.85; p < 0.005), after
adjustment for age, gender, initial BMI and center variability. Similarly, BES changes were associated
with BMI change (b = 0.15; t = 3.21; p < 0.001). We conclude that in subjects compliant to follow-up a
successful management of obesity, not directly addressing psychological distress, is associated with a
significant improvement of both psychological distress and binge eating, linearly related to the amount
of weight loss, independently of treatment procedures
New application of superconductors: high sensitivity cryogenic light detectors
In this paper we describe the current status of the CALDER project, which is
developing ultra-sensitive light detectors based on superconductors for
cryogenic applications. When we apply an AC current to a superconductor, the
Cooper pairs oscillate and acquire kinetic inductance, that can be measured by
inserting the superconductor in a LC circuit with high merit factor.
Interactions in the superconductor can break the Cooper pairs, causing sizable
variations in the kinetic inductance and, thus, in the response of the LC
circuit. The continuous monitoring of the amplitude and frequency modulation
allows to reconstruct the incident energy with excellent sensitivity. This
concept is at the basis of Kinetic Inductance Detectors (KIDs), that are
characterized by natural aptitude to multiplexed read-out (several sensors can
be tuned to different resonant frequencies and coupled to the same line),
resolution of few eV, stable behavior over a wide temperature range, and ease
in fabrication. We present the results obtained by the CALDER collaboration
with 2x2 cm2 substrates sampled by 1 or 4 Aluminum KIDs. We show that the
performances of the first prototypes are already competitive with those of
other commonly used light detectors, and we discuss the strategies for a
further improvement
Characterization of the KID-Based Light Detectors of CALDER
The aim of the Cryogenic wide-Area Light Detectors with Excellent Resolution
(CALDER) project is the development of light detectors with active area of
cm and noise energy resolution smaller than 20 eV RMS,
implementing phonon-mediated kinetic inductance detectors. The detectors are
developed to improve the background suppression in large-mass bolometric
experiments such as CUORE, via the double read-out of the light and the heat
released by particles interacting in the bolometers. In this work, we present
the characterization of the first light detectors developed by CALDER. We
describe the analysis tools to evaluate the resonator parameters (resonant
frequency and quality factors) taking into account simultaneously all the
resonance distortions introduced by the read-out chain (as the feed-line
impedance and its mismatch) and by the power stored in the resonator itself. We
detail the method for the selection of the optimal point for the detector
operation (maximizing the signal-to-noise ratio). Finally, we present the
response of the detector to optical pulses in the energy range of 0-30 keV
Energy resolution and efficiency of phonon-mediated Kinetic Inductance Detectors for light detection
The development of sensitive cryogenic light detectors is of primary interest
for bolometric experiments searching for rare events like dark matter
interactions or neutrino-less double beta decay. Thanks to their good energy
resolution and the natural multiplexed read-out, Kinetic Inductance Detectors
(KIDs) are particularly suitable for this purpose. To efficiently couple
KIDs-based light detectors to the large crystals used by the most advanced
bolometric detectors, active surfaces of several cm are needed. For this
reason, we are developing phonon-mediated detectors. In this paper we present
the results obtained with a prototype consisting of four 40 nm thick aluminum
resonators patterned on a 22 cm silicon chip, and calibrated with
optical pulses and X-rays. The detector features a noise resolution
eV and an (182) efficiency.Comment: 5 pages, 5 figure
Discovery of the Eu decay
We report on the first compelling observation of decay of Eu
to the ground state of Pm. The measurement was performed using a 6.15 g
LiEu(BO) crystal operated as a scintillating bolometer. The Q-value
and half-life measured are: Q = 1948.9 keV, and
T y . The
half-life prediction of nuclear theory using the Coulomb and proximity
potential model are in good agreement with this experimental result
Phonon and light read out of a Li 2MoO 4 crystal with multiplexed kinetic inductance detectors
Molybdenum based crystals such as Li 2MoO 4 and CaMoO4 are emerging as leading candidates for next generation experiments searching for neutrino-less double beta decay with cryogenic calorimeters (CUPID, AMoRE). The exquisite energy resolution and high radio-purity of these crystals come at the cost of a potentially detrimental background source: the two neutrinos double beta decay of 100Mo. Indeed, the fast half-life of this decay mode, combined with the slow response of cryogenic calorimeters, would result in pile-up events in the energy region of interest for neutrino-less double beta decay, reducing the experimental sensitivity. This background can be suppressed using fast and high sensitivity cryogenic light detectors, provided that the scintillation time constant itself does not limit the time resolution. We developed a new detection technique exploiting the high sensitivity, the fast time response and the multiplexing capability of Kinetic Inductance Detectors. We applied the proposed technique to a 2 × 2 × 2 cm3Li 2MoO 4 crystal, which was chosen as baseline option for CUPID. We measured simultaneously both the phonon and scintillation signals with KIDs. We derived the scintillation time constant of this compound at millikelvin temperatures obtaining tscint= 84.5 ± 4.5 (syst) ± 1.0 (stat) µs, constant between 10 and 190 mK
New experimental limits on the alpha decays of lead isotopes
For the first time a PbWO4 crystal was grown using ancient Roman lead and it
was run as a cryogenic detector. Thanks to the simultaneous and independent
read-out of heat and scintillation light, the detector was able to discriminate
beta/gamma interactions with respect to alpha particles down to low energies.
New more stringent limits on the alpha decays of the lead isotopes are
presented. In particular a limit of T_{1/2} > 1.4*10^20 y at a 90% C.L. was
evaluated for the alpha decay of 204Pb to 200Hg
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