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1.
Phys Rev Lett ; 131(22): 222501, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38101385

RESUMEN

We report on the results obtained with the global CUPID-0 background model, which combines the data collected in the two measurement campaigns for a total exposure of 8.82 kg×yr of ^{82}Se. We identify with improved precision the background sources within the 3 MeV energy region, where neutrinoless double ß decay of ^{82}Se and ^{100}Mo is expected, making more solid the foundations for the background budget of the next-generation CUPID experiment. Relying on the excellent data reconstruction, we measure the two-neutrino double ß-decay half-life of ^{82}Se with unprecedented accuracy: T_{1/2}^{2ν}=[8.69±0.05(stat)_{-0.06}^{+0.09}(syst)]×10^{19} yr.

2.
Phys Rev Lett ; 131(16): 162501, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37925694

RESUMEN

Neutrinoless double beta decay (0νßß) is a yet unobserved nuclear process that would demonstrate Lepton number violation, a clear evidence of beyond standard model physics. The process two neutrino double beta decay (2νßß) is allowed by the standard model and has been measured in numerous experiments. In this Letter, we report a measurement of 2νßß decay half-life of ^{100}Mo to the ground state of ^{100}Ru of [7.07±0.02(stat)±0.11(syst)]×10^{18} yr by the CUPID-Mo experiment. With a relative precision of ±1.6% this is the most precise measurement to date of a 2νßß decay rate in ^{100}Mo. In addition, we constrain higher-order corrections to the spectral shape, which provides complementary nuclear structure information. We report a novel measurement of the shape factor ξ_{3,1}=0.45±0.03(stat)±0.05(syst) based on a constraint on the ratio of higher-order terms from theory, which can be reliably calculated. This is compared to theoretical predictions for different nuclear models. We also extract the first value for the effective axial vector coupling constant obtained from a spectral shape study of 2νßß decay.

4.
Phys Rev Lett ; 129(22): 222501, 2022 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-36493444

RESUMEN

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.


Asunto(s)
Granisetrón , Semivida , Teorema de Bayes
5.
Phys Rev Lett ; 129(11): 111801, 2022 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-36154394

RESUMEN

CUPID-0, an array of Zn^{82}Se cryogenic calorimeters, was the first medium-scale demonstrator of the scintillating bolometers' technology. The first project phase (March 2017-December 2018) allowed the most stringent limit on the neutrinoless double beta decay half-life of the isotope of interest, ^{82}Se, to be set. After a six month long detector upgrade, CUPID-0 began its second and last phase (June 2019-February 2020). In this Letter, we describe the search for neutrinoless double beta decay of ^{82}Se with a total exposure (phase I+II) of 8.82 kg yr^{-1} of isotope. We set a limit on the half-life of ^{82}Se to the ground state of ^{82}Kr of T_{1/2}^{0ν}(^{82}Se)>4.6×10^{24} yr (90% credible interval), corresponding to an effective Majorana neutrino mass m_{ßß}<(263-545) meV. We also set the most stringent lower limits on the neutrinoless decays of ^{82}Se to the 0_{1}^{+}, 2_{1}^{+}, and 2_{2}^{+} excited states of ^{82}Kr, finding 1.8×10^{23} yr, 3.0×10^{23} yr, and 3.2×10^{23} yr (90% credible interval) respectively.

6.
Eur Phys J C Part Fields ; 81(8): 722, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34720725

RESUMEN

Localization and modeling of radioactive contaminations is a challenge that ultra-low background experiments are constantly facing. These are fundamental steps both to extract scientific results and to further reduce the background of the detectors. Here we present an innovative technique based on the analysis of α - α delayed coincidences in 232 Th and 238 U decay chains, developed to investigate the contaminations of the ZnSe crystals in the CUPID-0 experiment. This method allows to disentangle surface and bulk contaminations of the detectors relying on the different probability to tag delayed coincidences as function of the α decay position.

7.
Phys Rev Lett ; 126(18): 181802, 2021 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-34018798

RESUMEN

The CUPID-Mo experiment at the Laboratoire Souterrain de Modane (France) is a demonstrator for CUPID, the next-generation ton-scale bolometric 0νßß experiment. It consists of a 4.2 kg array of 20 enriched Li_{2}^{100}MoO_{4} scintillating bolometers to search for the lepton-number-violating process of 0νßß decay in ^{100}Mo. With more than one year of operation (^{100}Mo exposure of 1.17 kg×yr for physics data), no event in the region of interest and, hence, no evidence for 0νßß is observed. We report a new limit on the half-life of 0νßß decay in ^{100}Mo of T_{1/2}>1.5×10^{24} yr at 90% C.I. The limit corresponds to an effective Majorana neutrino mass ⟨m_{ßß}⟩<(0.31-0.54) eV, dependent on the nuclear matrix element in the light Majorana neutrino exchange interpretation.

8.
Phys Rev Lett ; 126(17): 171801, 2021 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-33988435

RESUMEN

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.

9.
Phys Rev Lett ; 124(12): 122501, 2020 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-32281829

RESUMEN

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.

10.
Phys Rev Lett ; 123(3): 032501, 2019 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-31386478

RESUMEN

CUPID-0 is the first pilot experiment of CUPID, a next-generation project for the measurement of neutrinoless double beta decay (0νDBD) with scintillating bolometers. The detector, consisting of 24 enriched and 2 natural ZnSe crystals, has been taking data at Laboratori Nazionali del Gran Sasso from June 2017 to December 2018, collecting a ^{82}Se exposure of 5.29 kg×yr. In this Letter we present the phase-I results in the search for 0νDBD. We demonstrate that the technology implemented by CUPID-0 allows us to reach the lowest background for calorimetric experiments: (3.5_{-0.9}^{+1.0})×10^{-3} counts/(keV kg yr). Monitoring 3.88×10^{25} ^{82}Se nuclei×yr we reach a 90% credible interval median sensitivity of T_{1/2}^{0ν}>5.0×10^{24} yr and set the most stringent limit on the half-life of ^{82}Se 0νDBD: T_{1/2}^{0ν}>3.5×10^{24} yr (90% credible interval), corresponding to m_{ßß}<(311-638) meV depending on the nuclear matrix element calculations.

11.
Phys Rev Lett ; 123(26): 262501, 2019 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-31951429

RESUMEN

We report on the measurement of the two-neutrino double-ß decay of ^{82}Se performed for the first time with cryogenic calorimeters, in the framework of the CUPID-0 experiment. With an exposure of 9.95 kg yr of Zn^{82}Se, we determine the two-neutrino double-ß decay half-life of ^{82}Se with an unprecedented precision level, T_{1/2}^{2ν}=[8.60±0.03(stat) _{-0.13}^{+0.19}(syst)]×10^{19} yr. The very high signal-to-background ratio, along with the detailed reconstruction of the background sources allowed us to identify the single state dominance as the underlying mechanism of such a process, demonstrating that the higher state dominance hypothesis is disfavored at the level of 5.5σ.

12.
Phys Rev Lett ; 120(13): 132501, 2018 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-29694201

RESUMEN

The CUORE experiment, a ton-scale cryogenic bolometer array, recently began operation at the Laboratori Nazionali del Gran Sasso in Italy. The array represents a significant advancement in this technology, and in this work we apply it for the first time to a high-sensitivity search for a lepton-number-violating process: ^{130}Te neutrinoless double-beta decay. Examining a total TeO_{2} exposure of 86.3 kg yr, characterized by an effective energy resolution of (7.7±0.5) keV FWHM and a background in the region of interest of (0.014±0.002) counts/(keV kg yr), we find no evidence for neutrinoless double-beta decay. Including systematic uncertainties, we place a lower limit on the decay half-life of T_{1/2}^{0ν}(^{130}Te)>1.3×10^{25} yr (90% C.L.); the median statistical sensitivity of this search is 7.0×10^{24} yr. Combining this result with those of two earlier experiments, Cuoricino and CUORE-0, we find T_{1/2}^{0ν}(^{130}Te)>1.5×10^{25} yr (90% C.L.), which is the most stringent limit to date on this decay. Interpreting this result as a limit on the effective Majorana neutrino mass, we find m_{ßß}<(110-520) meV, where the range reflects the nuclear matrix element estimates employed.

13.
Artículo en Inglés | MEDLINE | ID: mdl-26705394

RESUMEN

The LUCIFER project aims at deploying the first array of enriched scintillating bolometers for the investigation of neutrinoless double-beta decay of [Formula: see text]Se. The matrix which embeds the source is an array of ZnSe crystals, where enriched [Formula: see text]Se is used as decay isotope. The radiopurity of the initial components employed for manufacturing crystals, that can be operated as bolometers, is crucial for achieving a null background level in the region of interest for double-beta decay investigations. In this work, we evaluated the radioactive content in 2.5 kg of 96.3 % enriched [Formula: see text]Se metal, measured with a high-purity germanium detector at the Gran Sasso deep underground laboratory. The limits on internal contaminations of primordial decay chain elements of [Formula: see text]Th, [Formula: see text]U and [Formula: see text]U are respectively: [Formula: see text]61, [Formula: see text]110 and [Formula: see text]74 [Formula: see text]Bq/kg at 90 % C.L. The extremely low-background conditions in which the measurement was carried out and the high radiopurity of the [Formula: see text]Se allowed us to establish the most stringent lower limits on the half-lives of the double-beta decay of [Formula: see text]Se to 0[Formula: see text], 2[Formula: see text] and 2[Formula: see text] excited states of [Formula: see text]Kr of 3.4[Formula: see text]10[Formula: see text], 1.3[Formula: see text]10[Formula: see text] and 1.0[Formula: see text]10[Formula: see text] y, respectively, with a 90 % C.L.

14.
Phys Rev Lett ; 115(10): 102502, 2015 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-26382673

RESUMEN

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.

15.
Respir Med ; 101(8): 1830-5, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17376663

RESUMEN

Pulmonary rehabilitation (PR) improves physical capacity and health quality in patients with chronic obstructive pulmonary disease (COPD). However, the effect of exercise on oxidative stress markers in COPD patients is only partially known. This study was designed to evaluate the oxidative stress response to long-term exercise in patients with COPD enrolled in a PR program. Fifteen COPD patients (FEV1 < 60%), age between 50 and 60 years, ex-smokers, were separated in two groups: exercise-trained (n=8) and sedentary group (n=7). Exercise consisted of an 8-week conditioning program using a cycle ergometer (three times a week, 1h session). An endurance test (60% of maximal load in an incremental cycle test) was performed before and after PR. Blood samples were obtained at baseline and immediately after each endurance test. We measured the index of lipid peroxidation, thiobarbituric acid reactive species (TBARS), total radical-trapping antioxidant parameter (TRAP) and xanthine oxidase (XO) activity. TRAP was significantly different between the exercise-trained group and sedentary group of COPD patients. Baseline TBARS values were increased after the exercise training program but decreased after the endurance test. XO decrease after effort in the trained and untrained groups. The results suggest that patients with COPD are characterized by increased systemic and pulmonary oxidative stress markers both at rest as well as induced by cardiopulmonary exercise test and that PR program was associated with decreased systemic exercise-induced oxidative damage.


Asunto(s)
Terapia por Ejercicio , Estrés Oxidativo , Enfermedad Pulmonar Obstructiva Crónica/rehabilitación , Pruebas Respiratorias , Humanos , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Pruebas de Función Respiratoria
16.
J. pneumol ; 26(5): 269-272, set.-out. 2000. ilus
Artículo en Portugués | LILACS | ID: lil-339118

RESUMEN

É relatado o caso de um paciente portador da síndrome de Pancoast associada à síndrome da imunodeficiência adquirida. Esta apresentação é rara, visto que os tumores mais freqüentemente associados à SIDA são o sarcoma de Kaposi e o linfoma não-Hodgkin. O paciente, com passado de uso de drogas injetáveis, internou-se para investigação de massa em ápice pulmonar, com presença de síndrome de Pancoast, sendo solicitado anti-HIV, com resultado positivo, e tendo sido feito diagnóstico de Ca brônquico não-pequenas células


Asunto(s)
Humanos , Masculino , Adulto , Carcinoma Broncogénico/complicaciones , Síndrome de Inmunodeficiencia Adquirida/complicaciones , Síndrome de Pancoast/complicaciones , Carcinoma Broncogénico/diagnóstico , Síndrome de Inmunodeficiencia Adquirida/diagnóstico , Síndrome de Pancoast/diagnóstico
17.
Prensa méd. argent ; 84(1): 47-51, mar. 1997.
Artículo en Español | BINACIS | ID: bin-16867

RESUMEN

28 pacientes desarrollaron 36 seudoquistes del páncreas.Fueron operados:10 por drenaje externo;12 por derivaciones al tubo digestivo;6 pancreatectomías corporocaudales;1 duodenopancreatectomía;1 resección simple.En tres casos se asistió a la regresión espontánea;en otros dos se ocluyó la cistotrostomía y en un la cistoyeyunoanastomosis.En casos selectos los autores prefieren la resección;en los grandes y comunicantes se inclinan por las anastomosis quistodigestivas.Los inertes de actividad enzimática curan con la derivación externa o la resección.No parecehaber suficientes argumentos por anastomosis bajo control videocópico se halla en etapa de investigación


Asunto(s)
Adulto , Páncreas/cirugía
18.
Prensa méd. argent ; 84(1): 47-51, mar. 1997.
Artículo en Español | LILACS | ID: lil-225947

RESUMEN

28 pacientes desarrollaron 36 seudoquistes del páncreas.Fueron operados:10 por drenaje externo;12 por derivaciones al tubo digestivo;6 pancreatectomías corporocaudales;1 duodenopancreatectomía;1 resección simple.En tres casos se asistió a la regresión espontánea;en otros dos se ocluyó la cistotrostomía y en un la cistoyeyunoanastomosis.En casos selectos los autores prefieren la resección;en los grandes y comunicantes se inclinan por las anastomosis quistodigestivas.Los inertes de actividad enzimática curan con la derivación externa o la resección.No parecehaber suficientes argumentos por anastomosis bajo control videocópico se halla en etapa de investigación


Asunto(s)
Adulto , Páncreas/cirugía
19.
Radiol Med ; 86(6): 865-9, 1993 Dec.
Artículo en Italiano | MEDLINE | ID: mdl-8296009

RESUMEN

Brescia-Cimino arteriovenous fistulas are the most common vascular accesses in hemodialysis patients. Arterial blood pressure inside the vein and repeated punctures cause progressive sclerosis of the vessel wall and stenosis or occlusion are the final outcome. Percutaneous dilatation is an effective method to preserve arteriovenous fistulas function. From January 1991 through December 1992, eleven dilatations were performed in 10 patients (7 women and 3 men, mean age: 55 years) using a Zijlstra dedicated catheter provided with multiple infusion holes, which allows long dilatation times and therefore progressive wall distention. A high-pressure balloon yields better results in case of stiff and diffuse stenosis. The immediate results of the maneuver were good in all patients. One acute thrombosis of the fistula was observed a few hours after the procedure, and a second dilatation was performed in a patient 8 months after the first one. Mean arteriovenous fistula patency time was 6 months. Finally, a critical review of the international literature on the subject is made and the value of dilatation in the treatment of fistula stenosis is reported; the necessity to use new dedicated catheters in also stressed.


Asunto(s)
Angioplastia de Balón/instrumentación , Derivación Arteriovenosa Quirúrgica , Cateterismo/instrumentación , Complicaciones Posoperatorias/terapia , Adulto , Anciano , Constricción Patológica/terapia , Diseño de Equipo , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad
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