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2.
Phys Rev Lett ; 129(22): 222501, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36493444

RESUMO

The Cryogenic Underground Observatory for Rare Events (CUORE) at Laboratori Nazionali del Gran Sasso of INFN in Italy is an experiment searching for neutrinoless double beta (0νßß) decay. Its main goal is to investigate this decay in ^{130}Te, but its ton-scale mass and low background make CUORE sensitive to other rare processes as well. In this Letter, we present our first results on the search for 0νßß decay of ^{128}Te, the Te isotope with the second highest natural isotopic abundance. We find no evidence for this decay, and using a Bayesian analysis we set a lower limit on the ^{128}Te 0νßß decay half-life of T_{1/2}>3.6×10^{24} yr (90% CI). This represents the most stringent limit on the half-life of this isotope, improving by over a factor of 30 the previous direct search results, and exceeding those from geochemical experiments for the first time.


Assuntos
Granisetron , Meia-Vida , Teorema de Bayes
3.
Phys Rev Lett ; 126(17): 171801, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33988435

RESUMO

We measured two-neutrino double beta decay of ^{130}Te using an exposure of 300.7 kg yr accumulated with the CUORE detector. Using a Bayesian analysis to fit simulated spectra to experimental data, it was possible to disentangle all the major background sources and precisely measure the two-neutrino contribution. The half-life is in agreement with past measurements with a strongly reduced uncertainty: T_{1/2}^{2ν}=7.71_{-0.06}^{+0.08}(stat)_{-0.15}^{+0.12}(syst)×10^{20} yr. This measurement is the most precise determination of the ^{130}Te 2νßß decay half-life to date.

4.
Phys Rev Lett ; 124(12): 122501, 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32281829

RESUMO

We report new results from the search for neutrinoless double-beta decay in ^{130} Te with the CUORE detector. This search benefits from a fourfold increase in exposure, lower trigger thresholds, and analysis improvements relative to our previous results. We observe a background of (1.38±0.07)×10^{-2} counts/(keV kg yr)) in the 0νßß decay region of interest and, with a total exposure of 372.5 kg yr, we attain a median exclusion sensitivity of 1.7×10^{25} yr. We find no evidence for 0νßß decay and set a 90% credibility interval Bayesian lower limit of 3.2×10^{25} yr on the ^{130} Te half-life for this process. In the hypothesis that 0νßß decay is mediated by light Majorana neutrinos, this results in an upper limit on the effective Majorana mass of 75-350 meV, depending on the nuclear matrix elements used.

5.
Phys Rev Lett ; 115(10): 102502, 2015 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-26382673

RESUMO

We report the results of a search for neutrinoless double-beta decay in a 9.8 kg yr exposure of (130)Te using a bolometric detector array, CUORE-0. The characteristic detector energy resolution and background level in the region of interest are 5.1±0.3 keV FWHM and 0.058±0.004(stat)±0.002(syst)counts/(keV kg yr), respectively. The median 90% C.L. lower-limit half-life sensitivity of the experiment is 2.9×10(24) yr and surpasses the sensitivity of previous searches. We find no evidence for neutrinoless double-beta decay of (130)Te and place a Bayesian lower bound on the decay half-life, T(1/2)(0ν)>2.7×10(24) yr at 90% C.L. Combining CUORE-0 data with the 19.75 kg yr exposure of (130)Te from the Cuoricino experiment we obtain T(1/2)(0ν)>4.0×10(24) yr at 90% C.L. (Bayesian), the most stringent limit to date on this half-life. Using a range of nuclear matrix element estimates we interpret this as a limit on the effective Majorana neutrino mass, m(ßß)<270-760 meV.

6.
Phys Rev Lett ; 108(6): 062501, 2012 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-22401058

RESUMO

209Bi alpha decay to the ground and to the first excited state have been recently observed for the first time with a large BGO scintillating bolometer. The half-life of 209Bi is determined to be τ(1/2)=(2.01±0.08)×10(19) yr while the branching ratio for the ground-state to ground-state transition is (98.8±0.3)%.

7.
Behav Neurol ; 2020: 2846046, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32831969

RESUMO

Aphasia is a highly disabling acquired language disorder generally caused by a left-lateralized brain damage. Even if traditional therapies have been shown to induce an adequate clinical improvement, a large percentage of patients are left with some degree of language impairments. Therefore, new approaches to common speech therapies are urgently needed in order to maximize the recovery from aphasia. The recent application of virtual reality (VR) to aphasia rehabilitation has already evidenced its usefulness in promoting a more pragmatically oriented treatment than conventional therapies (CT). In the present study, thirty-six chronic persons with aphasia (PWA) were randomly assigned to two groups. The VR group underwent conversational therapy during VR everyday life setting observation, while the control group was trained in a conventional setting without VR support. All patients were extensively tested through a neuropsychological battery which included not only measures for language skills and communication efficacy but also self-esteem and quality of life questionnairies. All patients were trained through a conversational approach by a speech therapist twice a week for six months (total 48 sessions). After the treatment, no significant differences among groups were found in the different measures. However, the amount of improvement in the different areas was distributed over far more cognitive and psychological aspects in the VR group than in the control group. Indeed, the within-group comparisons showed a significant enhancement in different language tasks (i.e., oral comprehension, repetition, and written language) only in the VR group. Significant gains, after the treatment, were also found, in the VR group, in different psychological dimensions (i.e., self-esteem and emotional and mood state). Given the importance of these aspects for aphasia recovery, we believe that our results add to previous evidence which points to the ecological validity and feasibility of VR treatment for language recovery and psychosocial well-being.


Assuntos
Afasia , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Realidade Virtual , Afasia/terapia , Comunicação , Humanos , Qualidade de Vida
8.
PLoS One ; 13(8): e0200910, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30133443

RESUMO

This paper describes the production and chemical separation of the 163Ho isotope that will be used in several nuclear physics experiments aiming at measuring the neutrino mass as well as the neutron cross section of the 163Ho isotope. For this purpose, several batches of enriched 162Er have been irradiated at the Institut Laue-Langevin high flux reactor to finally produce 6 mg or 100 MBq of the desired 163Ho isotope. A portion of the Er/Ho mixture is then subjected to a sophisticated chemical separation involving ion exchange chromatography to isolate the Ho product from the Er target material. Before irradiation, a thorough analysis of the impurity content was performed and its implication on the produced nuclide inventory will be discussed.


Assuntos
Hólmio/química , Hólmio/isolamento & purificação , Radioquímica/métodos , Isótopos , Nêutrons , Física Nuclear
9.
Rev Sci Instrum ; 86(12): 124703, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26724052

RESUMO

In this work, we present the first part of the power supply system for the CUORE and LUCIFER arrays of bolometric detectors. For CUORE, it consists of AC/DC commercial power supplies (0-60 V output) followed by custom DC/DC modules (48 V input, ±5 V to ±13.5 V outputs). Each module has 3 floating and independently configurable output voltages. In LUCIFER, the AC/DC + DC/DC stages are combined into a commercial medium-power AC/DC source. At the outputs of both setups, we introduced filters with the aim of lowering the noise and to protect the following stages from high voltage spikes that can be generated by the energy stored in the cables after the release of accidental short circuits. Output noise is very low, as required: in the 100 MHz bandwidth the RMS level is about 37 µV(RMS) (CUORE setup) and 90 µV(RMS) (LUCIFER setup) at a load of 7 A, with a negligible dependence on the load current. Even more importantly, high frequency switching disturbances are almost completely suppressed. The efficiency of both systems is above 85%. Both systems are completely programmable and monitored via CAN bus (optically coupled).

10.
J Low Temp Phys ; 1842015 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-33087985

RESUMO

For experiments with high arrival rates, reliable identification of nearly-coincident events can be crucial. For calorimetric measurements to directly measure the neutrino mass such as HOLMES, unidentified pulse pile-ups are expected to be a leading source of experimental error. Although Wiener filtering can be used to recognize pile-up, it suffers errors due to pulse-shape variation from detector nonlinearity, readout dependence on sub-sample arrival times, and stability issues from the ill-posed deconvolution problem of recovering Dirac delta-functions from smooth data. Due to these factors, we have developed a processing method that exploits singular value decomposition to (1) separate single-pulse records from piled-up records in training data and (2) construct a model of single-pulse records that accounts for varying pulse shape with amplitude, arrival time, and baseline level, suitable for detecting nearly-coincident events. We show that the resulting processing advances can reduce the required performance specifications of the detectors and readout system or, equivalently, enable larger sensor arrays and better constraints on the neutrino mass.

11.
Eur Phys J C Part Fields ; 75(3): 112, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25995704

RESUMO

The European Research Council has recently funded HOLMES, a new experiment to directly measure the neutrino mass. HOLMES will perform a calorimetric measurement of the energy released in the decay of [Formula: see text]Ho. The calorimetric measurement eliminates systematic uncertainties arising from the use of external beta sources, as in experiments with beta spectrometers. This measurement was proposed in 1982 by A. De Rujula and M. Lusignoli, but only recently the detector technological progress allowed to design a sensitive experiment. HOLMES will deploy a large array of low temperature microcalorimeters with implanted [Formula: see text]Ho nuclei. The resulting mass sensitivity will be as low as 0.4 eV. HOLMES will be an important step forward in the direct neutrino mass measurement with a calorimetric approach as an alternative to spectrometry. It will also establish the potential of this approach to extend the sensitivity down to 0.1 eV. We outline here the project with its technical challenges and perspectives.

12.
Eur Phys J C Part Fields ; 73(5): 2431, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-25814859

RESUMO

The LHCb experiment has been taking data at the Large Hadron Collider (LHC) at CERN since the end of 2009. One of its key detector components is the Ring-Imaging Cherenkov (RICH) system. This provides charged particle identification over a wide momentum range, from 2-100 GeV/c. The operation and control, software, and online monitoring of the RICH system are described. The particle identification performance is presented, as measured using data from the LHC. Excellent separation of hadronic particle types (π, K, p) is achieved.

13.
Investig. psicol ; 17(3): 83-105, 2012. tab
Artigo em Espanhol | LILACS | ID: lil-675039

RESUMO

El objetivo del artículo es presentar los resultados correspondientes a una investigación que se enmarca en un proyecto UBACyT 2008-2010, cuyo título es “Evaluación Nacional de la Inteligencia Sensoriomotriz a bebés de 6 a 30 meses”. El objetivo principal de dicha investigación es conocer las etapas del proceso de construcción de la inteligencia práctica en bebés argentinos en las distintas provincias de la Argentina y la elaboración de nuevos baremos a nivel nacional para la Escala Argentina de Inteligencia Sensoriomotriz (EAIS). La muestra se encuentra compuesta por 800 niños de 6 a 30 meses de edad de las provincias de Buenos Aires y CABA, Córdoba, Entre Ríos, Santa Fe, Salta, Chaco, Misiones, Mendoza, Santa Cruz y Río Negro. No se observaron diferencias significativas entre las provincias argentinas en los niveles de desarrollo cognitivo en los bebés. No ha sido necesaria la elaboración de tablas diferenciales de baremos por región. Se presentan las tablas de baremos para la EAIS para la evaluación del desarrollo cognitivo en bebés de 6 a 30 meses de edad a nivel nacional.


Assuntos
Humanos , Lactente , Criança , Desenvolvimento Infantil , Inteligência , Testes de Inteligência , Argentina , Destreza Motora
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