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1.
Phys Rev Lett ; 131(2): 022501, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37505957

RESUMO

The ß decays from both the ground state and a long-lived isomer of ^{133}In were studied at the ISOLDE Decay Station (IDS). With a hybrid detection system sensitive to ß, γ, and neutron spectroscopy, the comparative partial half-lives (logft) have been measured for all their dominant ß-decay channels for the first time, including a low-energy Gamow-Teller transition and several first-forbidden (FF) transitions. Uniquely for such a heavy neutron-rich nucleus, their ß decays selectively populate only a few isolated neutron unbound states in ^{133}Sn. Precise energy and branching-ratio measurements of those resonances allow us to benchmark ß-decay theories at an unprecedented level in this region of the nuclear chart. The results show good agreement with the newly developed large-scale shell model (LSSM) calculations. The experimental findings establish an archetype for the ß decay of neutron-rich nuclei southeast of ^{132}Sn and will serve as a guide for future theoretical development aiming to describe accurately the key ß decays in the rapid-neutron capture (r-) process.

2.
Phys Rev Lett ; 129(17): 172701, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36332266

RESUMO

The ß-delayed one- and two-neutron emission probabilities (P_{1n} and P_{2n}) of 20 neutron-rich nuclei with N≥82 have been measured at the RIBF facility of the RIKEN Nishina Center. P_{1n} of ^{130,131}Ag, ^{133,134}Cd, ^{135,136}In, and ^{138,139}Sn were determined for the first time, and stringent upper limits were placed on P_{2n} for nearly all cases. ß-delayed two-neutron emission (ß2n) was unambiguously identified in ^{133}Cd and ^{135,136}In, and their P_{2n} were measured. Weak ß2n was also detected from ^{137,138}Sn. Our results highlight the effect of the N=82 and Z=50 shell closures on ß-delayed neutron emission probability and provide stringent benchmarks for newly developed macroscopic-microscopic and self-consistent global models with the inclusion of a statistical treatment of neutron and γ emission. The impact of our measurements on r-process nucleosynthesis was studied in a neutron star merger scenario. Our P_{1n} and P_{2n} have a direct impact on the odd-even staggering of the final abundance, improving the agreement between calculated and observed Solar System abundances. The odd isotope fraction of Ba in r-process-enhanced (r-II) stars is also better reproduced using our new data.

3.
Phys Rev Lett ; 125(19): 192501, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33216605

RESUMO

The ß decay of ^{208}Hg into the one-proton hole, one neutron-particle _{81}^{208}Tl_{127} nucleus was investigated at CERN-ISOLDE. Shell-model calculations describe well the level scheme deduced, validating the proton-neutron interactions used, with implications for the whole of the N>126, Z<82 quadrant of neutron-rich nuclei. While both negative and positive parity states with spin 0 and 1 are expected within the Q_{ß} window, only three negative parity states are populated directly in the ß decay. The data provide a unique test of the competition between allowed Gamow-Teller and Fermi, and first-forbidden ß decays, essential for the understanding of the nucleosynthesis of heavy nuclei in the rapid neutron capture process. Furthermore, the observation of the parity changing 0^{+}→0^{-}ß decay where the daughter state is core excited is unique, and can provide information on mesonic corrections of effective operators.

4.
Phys Rev Lett ; 124(6): 062502, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32109128

RESUMO

The nuclei below lead but with more than 126 neutrons are crucial to an understanding of the astrophysical r process in producing nuclei heavier than A∼190. Despite their importance, the structure and properties of these nuclei remain experimentally untested as they are difficult to produce in nuclear reactions with stable beams. In a first exploration of the shell structure of this region, neutron excitations in ^{207}Hg have been probed using the neutron-adding (d,p) reaction in inverse kinematics. The radioactive beam of ^{206}Hg was delivered to the new ISOLDE Solenoidal Spectrometer at an energy above the Coulomb barrier. The spectroscopy of ^{207}Hg marks a first step in improving our understanding of the relevant structural properties of nuclei involved in a key part of the path of the r process.

5.
Phys Rev Lett ; 121(14): 142701, 2018 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-30339438

RESUMO

The ^{12}C(α,γ)^{16}O reaction plays a central role in astrophysics, but its cross section at energies relevant for astrophysical applications is only poorly constrained by laboratory data. The reduced α width, γ_{11}, of the bound 1^{-} level in ^{16}O is particularly important to determine the cross section. The magnitude of γ_{11} is determined via sub-Coulomb α-transfer reactions or the ß-delayed α decay of ^{16}N, but the latter approach is presently hampered by the lack of sufficiently precise data on the ß-decay branching ratios. Here we report improved branching ratios for the bound 1^{-} level [b_{ß,11}=(5.02±0.10)×10^{-2}] and for ß-delayed α emission [b_{ßα}=(1.59±0.06)×10^{-5}]. Our value for b_{ßα} is 33% larger than previously held, leading to a substantial increase in γ_{11}. Our revised value for γ_{11} is in good agreement with the value obtained in α-transfer studies and the weighted average of the two gives a robust and precise determination of γ_{11}, which provides significantly improved constraints on the ^{12}C(α,γ) cross section in the energy range relevant to hydrostatic He burning.

8.
Health Care Strateg Manage ; 11(11): 14-7, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10129686

RESUMO

With or without federal health care reform to impact the delivery of health care services in the U.S., hospitals must commit to service marketing and strategic alliances as a fundamental business strategy. Service marketing not only differentiates the provider, but with the proper programs in place, it may actually facilitate the formation of strategic alliances. The combination of these strategies will be particularly effective in preparing for any health care policy change.


Assuntos
Assistência Integral à Saúde/organização & administração , Administração Hospitalar/tendências , Relações Interinstitucionais , Marketing de Serviços de Saúde/tendências , Comportamento do Consumidor , Coalizão em Cuidados de Saúde , Marketing de Serviços de Saúde/métodos , Técnicas de Planejamento , Estados Unidos
10.
Healthc Financ Manage ; 46(10): 55-6, 58, 60, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10145690

RESUMO

The implementation of automated marketing management systems in hospitals across the United States can change dramatically the way in which a hospital builds business by managing relationships with prospective customers.


Assuntos
Comportamento do Consumidor/estatística & dados numéricos , Administração Financeira de Hospitais , Sistemas de Informação Administrativa , Marketing de Serviços de Saúde/organização & administração , Coleta de Dados , Estudos de Avaliação como Assunto , Renda/estatística & dados numéricos , Estados Unidos
11.
Comput Healthc ; 13(1): 30-3, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10116596

RESUMO

Although the industry has begun to embrace the role of marketing in healthcare, this recognition has not been matched by a commensurate commitment of capital resources, including expenditures for information systems that help healthcare managers to market "smart".


Assuntos
Sistemas de Informação Hospitalar/tendências , Marketing de Serviços de Saúde/métodos , Comportamento do Consumidor/economia , Sistemas de Apoio a Decisões Administrativas , Marketing de Serviços de Saúde/tendências , Sistemas On-Line , Encaminhamento e Consulta/organização & administração , Telefone , Estados Unidos
12.
Health Care Strateg Manage ; 9(7): 16-7, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10111540

RESUMO

Telemarketing has been used for decades to increase revenues for companies in every industry. But how can a Teleservices Center (TSC), the next generation of the telemarketing scheme, fit into a hospital's strategy for growth? The author suggests the importance of this technique to increase referrals and the number of physicians bonded to the institution.


Assuntos
Planejamento Hospitalar/tendências , Marketing de Serviços de Saúde/métodos , Telecomunicações , Bases de Dados Bibliográficas , Renda , Técnicas de Planejamento , Estados Unidos
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