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2.
Phys Rev Lett ; 124(3): 032502, 2020 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-32031845

RESUMEN

Radioactive ^{129}Sb, which can be treated as a proton plus semimagic ^{128}Sn core within the particle-core coupling scheme, was studied by Coulomb excitation. Reduced electric quadrupole transition probabilities, B(E2), for the 2^{+}⊗πg_{7/2} multiplet members and candidate πd_{5/2} state were measured. The results indicate that the total electric quadrupole strength of ^{129}Sb is a factor of 1.39(11) larger than the ^{128}Sn core, which is in stark contrast to the expectations of the empirically successful particle-core coupling scheme. Shell-model calculations performed with two different sets of nucleon-nucleon interactions suggest that this enhanced collectivity is due to constructive quadrupole coherence in the wave functions stemming from the proton-neutron residual interactions, where adding one nucleon to a core near a double-shell closure can have a pronounced effect. The enhanced electric quadrupole strength is an early signal of the emerging nuclear collectivity that becomes dominant away from the shell closure.

3.
Phys Rev Lett ; 118(9): 092503, 2017 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-28306272

RESUMEN

Radioactive ^{136}Te has two valence protons and two valence neutrons outside of the ^{132}Sn double shell closure, providing a simple laboratory for exploring the emergence of collectivity and nucleon-nucleon interactions. Coulomb excitation of ^{136}Te on a titanium target was utilized to determine an extensive set of electromagnetic moments for the three lowest-lying states, including B(E2;0_{1}^{+}→2_{1}^{+}), Q(2_{1}^{+}), and g(2_{1}^{+}). The results indicate that the first-excited state, 2_{1}^{+}, composed of the simple 2p⊕2n system, is prolate deformed, and its wave function is dominated by excited valence neutron configurations, but not to the extent previously suggested. It is demonstrated that extreme sensitivity of g(2_{1}^{+}) to the proton and neutron contributions to the wave function provides unique insight into the nature of emerging collectivity, and g(2_{1}^{+}) was used to differentiate among several state-of-the-art theoretical calculations. Our results are best described by the most recent shell model calculations.

4.
Phys Rev Lett ; 116(12): 122502, 2016 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-27058074

RESUMEN

The lifetimes of the first excited 2^{+} and 4^{+} states in ^{72}Ni were measured at the National Superconducting Cyclotron Laboratory with the recoil-distance Doppler-shift method, a model-independent probe to obtain the reduced transition probability. Excited states in ^{72}Ni were populated by the one-proton knockout reaction of an intermediate energy ^{73}Cu beam. γ-ray-recoil coincidences were detected with the γ-ray tracking array GRETINA and the S800 spectrograph. Our results provide evidence of enhanced transition probability B(E2;2^{+}→0^{+}) as compared to ^{68}Ni, but do not confirm the trend of large B(E2) values reported in the neighboring isotope ^{70}Ni obtained from Coulomb excitation measurement. The results are compared to shell model calculations. The lifetime obtained for the excited 4_{1}^{+} state is consistent with models showing decay of a seniority ν=4, 4^{+} state, which is consistent with the disappearance of the 8^{+} isomer in ^{72}Ni.

5.
Phys Rev Lett ; 112(17): 172701, 2014 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-24836240

RESUMEN

Single-neutron states in (133)Sn and (209)Pb, which are analogous to single-electron states outside of closed atomic shells in alkali metals, were populated by the ((9)Be, (8)Be) one-neutron transfer reaction in inverse kinematics using particle-γ coincidence spectroscopy. In addition, the s(1/2) single-neutron hole-state candidate in (131)Sn was populated by ((9)Be, (10)Be). Doubly closed-shell (132)Sn (radioactive) and (208)Pb (stable) beams were used at sub-Coulomb barrier energies of 3 MeV per nucleon. Level energies, γ-ray transitions, absolute cross sections, spectroscopic factors, asymptotic normalization coefficients, and excited-state lifetimes are reported and compared with shell-model expectations. The results include a new transition and precise level energy for the 3p(1/2) candidate in (133)Sn, new absolute cross sections for the 1h(9/2) candidate in (133)Sn and 3s(1/2) candidate in (131)Sn, and new lifetimes for excited states in (133)Sn and (209)Pb. This is the first report on excited-state lifetimes of (133)Sn, which allow for a unique test of the nuclear shell model and (132)Sn double-shell closure.

6.
Phys Rev Lett ; 109(3): 032504, 2012 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-22861842

RESUMEN

The nucleus 49Sc, having a single f(7/2) proton outside doubly magic 48Ca (Z=20, N=28), is one of the very few isotopes which makes possible testing of the fundamental theory of nuclear magnetism. The magnetic moment has been measured by online ß NMR of nuclei oriented at milli-Kelvin temperatures to be (+)5.616(25) µ(N). The result is discussed in terms of a detailed theory of the structure of the magnetic moment operator, showing excellent agreement with calculated departure from the f(7/2) Schmidt limit extreme single-particle value. The measurement completes the sequence of moments of Sc isotopes with even numbers of f(7/2) neutrons: the first such isotopic chain between two major shells for which a full set of moment measurements exists. The result further completes the isotonic sequence of ground-state moments of nuclei with an odd number of f(7/2) protons coupled to a closed subshell of f(7/2) neutrons. Comparison with a recent shell-model calculation of the latter sequence is made.

7.
Phys Rev Lett ; 105(16): 162502, 2010 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-21230967

RESUMEN

By studying the (109)Xe→(105)Te→(101)Sn superallowed α-decay chain, we observe low-lying states in (101)Sn, the one-neutron system outside doubly magic (100)Sn. We find that the spins of the ground state (J=7/2) and first excited state (J=5/2) in (101)Sn are reversed with respect to the traditional level ordering postulated for (103)Sn and the heavier tin isotopes. Through simple arguments and state-of-the-art shell-model calculations we explain this unexpected switch in terms of a transition from the single-particle regime to the collective mode in which orbital-dependent pairing correlations dominate.

8.
Artículo en Inglés | MEDLINE | ID: mdl-18184510

RESUMEN

This study identified casualty crash types for which teen drivers experience excess risk relative to adults. Michigan State Police crash records were used to examine casualty crashes in two statewide populations of drivers who experienced at least one crash from 1989-1996 (pre-graduated driver licensing in Michigan): teens (ages 16-19) and adults (ages 45-65). Rates and rate ratios (RR) based on crash occurrence per 100,000 person miles driven (PMD) compared teens and adults from the two statewide populations. Excess risk was defined as a RR for a specific type of crash that was significantly greater than the RR for all crashes combined. The RRs for all crashes combined for teenage males was 2.41 and 1.75 for teenage females. RRs for teenage males ranged from a low of 2.16 for casualty crashes attributed to alcohol to 8.98 for casualty road departure crashes at night. Among teenage females, RRs ranged from 2.06 for casualty crashes on the weekend to 7.86 for casualty crashes at night with passengers. Casualty crash rates for teenage males ranged from 0.21 per 100,000 PMD for rollover crashes to 1.95 per 100,000 PMD for crashes with passengers. Among teen females, casualty crash rates ranged from 0.21 per 100,000 PMD for drink/driving with passengers to 3.31 per 100,000 PMD for crashes with passengers. Implications for graduated driver licensing, teen driver supervision, and policy are discussed. This study was funded by the National Institute on Alcohol Abuse and Alcoholism and the Centers for Disease Control and Prevention's National Center for Injury Prevention and Control.


Asunto(s)
Accidentes de Tránsito/estadística & datos numéricos , Conducción de Automóvil/estadística & datos numéricos , Automóviles/estadística & datos numéricos , Adolescente , Anciano , Femenino , Humanos , Masculino , Michigan , Persona de Mediana Edad , Medición de Riesgo , Factores de Riesgo , Estados Unidos
9.
J Clin Psychiatry ; 62(9): 728-32, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11681770

RESUMEN

BACKGROUND: Use of antipsychotic medication intermittently or over the long term may be necessary in treating patients with bipolar disorder whose symptoms have responded suboptimally to standard mood-stabilizing agents. Quetiapine fumarate is an effective novel antipsychotic with mixed serotonergic (5-HT2) and dopaminergic (D2) activity. This is an open-label, 12-week prospective study to assess the efficacy and tolerability of quetiapine in the treatment of patients with bipolar and schizoaffective disorder who were suboptimally responsive to mood stabilizers alone. METHOD: Participants in the study were inpatients or outpatients with a DSM-IV diagnosis of bipolar or schizoaffective disorder. Baseline psychopathology was evaluated with the Brief Psychiatric Rating Scale (BPRS), the Young Mania Rating Scale (YMRS), and the Hamilton Rating Scale for Depression (HAM-D). Involuntary movements were rated with the Simpson-Angus Neurologic Rating Scale. Quetiapine was added on an open-label basis and increased to optimum clinical dosage. Psychopathology and Abnormal Involuntary Movement Scale ratings were repeated weekly for the first 4 weeks and then again at weeks 8 and 12. RESULTS: Ten individuals with bipolar disorder and 10 with schizoaffective disorder received quetiapine therapy. Overall, patients improved, with significant improvement in BPRS (p < .001), YMRS (p = .043), and HAM-D scores (p = .002). Simpson-Angus score also significantly decreased (p = .02). Overall. quetiapine was well tolerated by patients in this group with serious mood disorders. The mean +/- SD quetiapine dose was 202.9 +/- 124.3 mg/day (range, 50-400 mg/day). Mean weight gain was 10.9 lb (4.9 kg). CONCLUSION: Although limited by its small size, open-label design, and relative gender homogeneity, this study suggests that quetiapine therapy may be useful in the treatment of individuals with serious mood disorders who are suboptimally responsive to mood stabilizers alone. These preliminary findings should be explored in larger, controlled trials.


Asunto(s)
Antipsicóticos/uso terapéutico , Trastorno Bipolar/tratamiento farmacológico , Dibenzotiazepinas/uso terapéutico , Litio/uso terapéutico , Trastornos Psicóticos/tratamiento farmacológico , Ácido Valproico/uso terapéutico , Adulto , Anciano , Antipsicóticos/efectos adversos , Trastorno Bipolar/diagnóstico , Escalas de Valoración Psiquiátrica Breve/estadística & datos numéricos , Dibenzotiazepinas/efectos adversos , Esquema de Medicación , Quimioterapia Combinada , Femenino , Hospitalización , Humanos , Litio/efectos adversos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Escalas de Valoración Psiquiátrica/estadística & datos numéricos , Trastornos Psicóticos/diagnóstico , Fumarato de Quetiapina , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Ácido Valproico/efectos adversos , Aumento de Peso
10.
J Consult Clin Psychol ; 64(6): 1245-54, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8991311

RESUMEN

L. Benjamin's (1984) structural analysis of social behavior (SASB) system was used as the organizing framework within which to characterize the phenomenology of self and other relationship experience among subtypes of alcoholic men. Within the context of a community-based study of psychopathology, groups of antisocial alcoholic (AAL), nonantisocial alcoholic (NAAL), and nonalcoholic (control) men completed ratings of their introject (self-concept) and spousal experience. Group differences in demography and psychopathology provided strong support for subtype variations among alcoholic men that could not be attributed to global differences in adaptive functioning. SASB data showed consistency in circumplex ordering across the groups in ratings of self-experience and in ratings of the spousal relationship. AAL men were the most self-neglecting, blaming, and least trusting, and control men were the most relationally connected, with NAAL men falling in between. Despite the importance of the subtyping distinction, in some areas, alcoholism, regardless of subtype, was the core differentiating factor.


Asunto(s)
Alcoholismo/psicología , Autoimagen , Conducta Social , Adulto , Humanos , Masculino
11.
Psychiatr Serv ; 51(6): 795-800, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10828113

RESUMEN

OBJECTIVE: Limited data exist on differential rates of psychiatric diagnoses between ethnocultural groups in the elderly population. The purpose of this study was to examine more closely the issue of race and rates of psychiatric diagnoses among elderly inpatients. METHODS: The national sample included 23,758 veterans age 60 or over admitted in 1994 to acute inpatient units in Department of Veterans Affairs (VA) hospitals. Psychiatric diagnosis determined inclusion in one of six diagnostic groups: cognitive, mood, psychotic, substance use, anxiety, and other disorders. The study also assessed rates of psychiatric diagnoses among patients admitted to psychiatric units only and by age group and treatment setting, such as the size of the hospital and whether it had an academic affiliation. RESULTS: Compared with elderly Hispanic and Caucasian patients, a significantly higher proportion of elderly African-American patients were diagnosed as having cognitive disorders and substance use disorders, and a significantly lower proportion were diagnosed as having mood and anxiety disorders. Hispanic and African-American patients had significantly higher rates of psychotic diagnoses than Caucasian patients. For all diagnoses except cognitive disorders, these differential rates were also found among patients admitted to psychiatric units only. Age and treatment setting appeared to moderate some of the differences in diagnostic rates, except for mood disorders. In every analysis performed, the rate of mood disorder diagnoses among elderly African-American patients was less than half the rate among elderly Caucasian patients. CONCLUSIONS: The findings suggest that elderly African-American veterans admitted to VA inpatient units have strikingly lower rates of mood disorder diagnoses. Future studies should examine the contribution of both patient and provider factors to these differences.


Asunto(s)
Negro o Afroamericano/psicología , Hispánicos o Latinos/psicología , Trastornos Mentales/diagnóstico , Trastornos Mentales/rehabilitación , Veteranos/psicología , Anciano , Áreas de Influencia de Salud , Hospitalización , Hospitales Psiquiátricos , Hospitales de Veteranos , Humanos , Trastornos Mentales/epidemiología , Índice de Severidad de la Enfermedad , Estados Unidos
12.
Psychiatr Serv ; 51(5): 669-71, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10783190

RESUMEN

Clozapine therapy for 2,996 patients with treatment-refractory schizophrenia was examined over a five-year period in the Veterans Affairs health care system. Patients were assessed with the Brief Psychiatric Rating Scale (BPRS) and the Abnormal Involuntary Movement Scale (AIMS). BPRS scores, which were available for 522 patients, indicated a significant improvement, as did AIMS scores, which were available for 252 patients. Compared with individuals who showed a modest improvement, those with a more robust response to clozapine had higher initial BPRS scores and were three times more likely to have been suicidal in the month before starting clozapine therapy.


Asunto(s)
Antipsicóticos/uso terapéutico , Clozapina/uso terapéutico , Esquizofrenia/tratamiento farmacológico , Veteranos/psicología , Adulto , Anciano , Anciano de 80 o más Años , Antipsicóticos/efectos adversos , Clozapina/efectos adversos , Discinesia Inducida por Medicamentos/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Examen Neurológico/efectos de los fármacos , Escalas de Valoración Psiquiátrica , Esquizofrenia/diagnóstico
13.
Am J Orthopsychiatry ; 70(3): 389-400, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10953785

RESUMEN

This is the first study to test concurrently the effectiveness of four treatment programs for patients with serious mental illness. Three-year outcome data on utilization and functioning demonstrated important positive changes for seriously mentally ill veterans enrolled in specialized, enhanced inpatient and community case management treatment programs, when compared to patients in an enhanced day treatment program or traditional standard care.


Asunto(s)
Manejo de Caso , Servicios Comunitarios de Salud Mental , Centros de Día , Admisión del Paciente , Trastornos Psicóticos/rehabilitación , Veteranos/psicología , Adulto , Anciano , Enfermedad Crónica , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Procesos y Resultados en Atención de Salud , Trastornos Psicóticos/psicología
14.
J Adolesc Res ; 5(1): 18-33, 1990 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12343095

RESUMEN

A subsample of 814 sexually experienced adolescent females from the 1979 U.S. National Survey of Young Women was analyzed to assess the correlates of age at 1st sexual intercourse. Multiple regression procedures were used to examine sets of variables sequentially. In the hierarchical regression model, the control variables (respondent's age, race, religion, and age at menarche), along with 3 independent variables (household income, ideal age at 1st marriage, and ideal age for 1st birth), predicted age at 1st intercourse. The control variables accounted for a major portion of the variance in the model. Of the controls, chronological age and age at menarche were highly significant across all models tested.


Asunto(s)
Adolescente , Distribución por Edad , Actitud , Recolección de Datos , Escolaridad , Etnicidad , Composición Familiar , Renta , Menarquia , Modelos Teóricos , Religión , Conducta Sexual , Factores Socioeconómicos , Estadística como Asunto , Factores de Edad , Américas , Conducta , Cultura , Demografía , Países Desarrollados , Economía , Menstruación , América del Norte , Población , Características de la Población , Psicología , Reproducción , Investigación , Clase Social , Estados Unidos
15.
J Adolesc Health ; 51(5): 484-90, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23084170

RESUMEN

INTRODUCTION: Much is known about sex and age differences in collision types, but most studies have examined the effect of declining physical and mental capabilities on older drivers' performance. Fewer studies have focused on the relationship between younger driver's sex and crash type, and these studies have largely ignored the multidimensionality of crashes, have not consistently examined sex differences, and are based on outdated data. This study addressed these issues by examining differences in the likelihood of involvement in seven crash configurations between adolescent and adult male and female drivers. METHOD: Fatal crash data from the Fatality Analysis Reporting System and nonfatal crash data from the General Estimation System for years 2005-2009 were used. Crash configurations were identified using point of initial impact, manner of collision, and vehicle action (i.e., striking or struck). Logistic regression estimated relative odds ratios among four driver groups: male and female drivers aged 15-19 years, and male and female drivers aged 45-64 years. RESULTS: Crash likelihood varied dramatically by driver age and sex across crash configuration. Adolescent male drivers were most likely to be in single-vehicle and fatal head-on crashes; adolescent drivers had a higher likelihood of front-to-rear crashes; adults had the highest likelihood of rear-end crashes; and female drivers had higher likelihoods of left- and right-side crashes. CONCLUSIONS: These findings may result from differences in driving experience, driving styles, or cognitive spatial abilities. Future research is needed to identify contributors to different crash configurations so that they can be directly addressed through tailored interventions and programs.


Asunto(s)
Accidentes de Tránsito/clasificación , Accidentes de Tránsito/estadística & datos numéricos , Conducción de Automóvil/estadística & datos numéricos , Adolescente , Factores de Edad , Femenino , Humanos , Masculino , Oportunidad Relativa , Análisis de Regresión , Riesgo , Factores Sexuales , Estados Unidos , Adulto Joven
16.
J Safety Res ; 42(3): 193-7, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21855690

RESUMEN

BACKGROUND: This study compared driving exposure between two high-crash-risk groups (16-17 and 18-24-year-olds), with a low-crash-risk group (35-64-year-olds). In addition, patterns of association between driving exposure measures and demographic and driving behavior variables were examined. METHODS: Respondent's total miles, minutes, and trips driven were calculated within a 48-hour period, using state-wide survey data collected in 2004 and 2005. RESULTS: The youngest drivers drove fewer miles and minutes, but a comparable number of trips as the two older groups. Employment and high vehicle access were associated with greater driving exposure for 16-17-year-olds and 18-24-year-olds. Employment, high household income, large household size, and low vehicle access were associated with greater driving exposure for 35-64-year-olds. More driving was done alone than with passengers present and during the day than at night across all ages. There was a positive association between two driving exposure measures (miles and minutes driven) and demographic and driving behavior variables, which did not extend to trips driven. DISCUSSION: Driving exposure is directly related to stage of life. The entire sample of 16-17-year-old respondents were in high school, which directly influenced their driving times, destinations, and purpose. Those aged 18-24years displayed driving behavior patterns that were closer to the older drivers, while retaining some differences. The oldest drivers were likely to be shouldering the greatest household responsibilities, and their greater driving exposure may reflect this reality. IMPACT ON INDUSTRY: These findings provide new information about driving exposure for two high-risk and one low-risk group of drivers. They also raise concern over potential workplace safety issues related to teens' higher driving exposure, and concomitant crash risk, related to being employed. Future research should examine this issue more carefully so that evidence based recommendations can be made to enhance the safety of teens who are employed, especially those who are employed as drivers.


Asunto(s)
Conducción de Automóvil/estadística & datos numéricos , Empleo , Accidentes de Tránsito , Actividades Cotidianas , Adolescente , Adulto , Factores de Edad , Recolección de Datos , Composición Familiar , Femenino , Humanos , Renta , Masculino , Michigan , Persona de Mediana Edad , Adulto Joven
17.
Accid Anal Prev ; 42(4): 1386-91, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20441856

RESUMEN

Motor vehicle crashes are the leading cause of death and a leading cause of non-fatal injury for teenagers in the United States. Understanding teen crashes requires a good measure of crash risk. The measure of exposure that is used in the calculation of risk estimates determines what information the resulting rates and rate ratios provide and the conclusions that can be drawn about teen driver crash risk. The purpose of this study is to provide an initial description of three measures of individual-level exposure to driving for 16-17-year-olds in the state of Michigan, using data from the state-wide Michigan Travel Counts survey conducted in 2004 and 2005. The total miles, minutes, and trips driven within the 48-h survey period were calculated for each respondent using self-reported measures and geo-spatial mapping. Young drivers who worked and those with greater access to a vehicle drove significantly more than their peers who did not work and those who had less access to a vehicle. Those from urban residences spent more time driving than those from rural residences. All 16-17-year-olds drove substantially more during the day than at night, and on their own than with passengers. There was little difference in overall driving exposure and driving behavior between young men and young women. This study provides an initial description of driving exposure and behavior for a population for which there is very little specific information about amounts and patterns of individual driving exposure. The relationship between individual driving exposure and risk of motor vehicle crash, injury or fatality requires further investigation.


Asunto(s)
Accidentes de Tránsito/estadística & datos numéricos , Conducta del Adolescente , Conducción de Automóvil/estadística & datos numéricos , Adolescente , Factores de Edad , Demografía , Empleo , Femenino , Humanos , Masculino , Michigan , Medición de Riesgo , Factores de Tiempo
18.
Phys Rev Lett ; 98(21): 212501, 2007 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-17677769

RESUMEN

An alpha-decay branch of (1.4+/-0.4) x 10(-4) has been discovered in the decay of 109I, which predominantly decays via proton emission. The measured Q(alpha) value of 3918+/-21 keV allows the indirect determination of the Q value for proton emission from 105Sb of 356+/-22 keV, which is approximately of 130 keV more bound than previously reported. This result is relevant for the astrophysical rapid proton-capture process, which would terminate in the 105Sn(p,gamma)106Sb(p,gamma)107Te(alpha decay)103Sn cycle at the densities expected in explosive hydrogen burning scenarios, unless unusually strong pairing effects result in a 103Sn(p,gamma)104Sb(p,gamma)105Te(alpha decay)101Sn) cycle.

19.
Phys Rev Lett ; 99(19): 192501, 2007 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-18233071

RESUMEN

The decay of extremely neutron-deficient 45Fe has been studied in detail by means of a novel type of a gaseous detector employing digital imaging to record tracks of charged particles. The two-proton radioactivity channel was clearly identified. For the first time, the angular and energy correlations between two protons emitted from the nuclear ground state were determined, indicating the genuine three-body character of this decay. The half-life of 45Fe was found to be 2.6+/-0.2 ms and the observed 2p decay branching ratio is 70+/-4%.

20.
Phys Rev Lett ; 97(8): 082501, 2006 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-17026296

RESUMEN

Two new alpha emitters 109Xe and 105Te were identified through the observation of the 109Xe --> 105Te --> 101Sn alpha-decay chain. The 109Xe nuclei were produced in the fusion-evaporation reaction 54Fe(58Ni,3n)109Xe and studied using the Recoil Mass Spectrometer at the Holifield Radioactive Ion Beam Facility. Two transitions at Ealpha = 4062 +/- 7 keV and Ealpha = 3918 +/- 9 keV were interpreted as the l = 2 and l = 0 transitions from the 7/2+ ground state in 109Xe (T1/2 = 13 +/- 2 ms) to the 5/2+ ground state and a 7/2+ excited state, located at 150 +/- 13 keV in 105Te. The observation of the subsequent decay of 105Te marks the discovery of the lightest known alpha-decaying nucleus. The measured transition energy Ealpha = 4703 +/- 5 keV and half-life T1/2 = 620 +/- 70 ns were used to determine the reduced alpha-decay width delta2. The ratio delta105Te(2)/delta213Po(2) of approximately 3 indicates a superallowed character of the alpha emission from 105Te.

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