Search results for "Internal conversion"

β-decay ofO13

2005

The beta decay of O-13 has been studied at the IGISOL facility of the Jyvaskyla accelerator centre (Finland). By developing a low-energy isotope-separated beam of O-13 and using a modern segmented charged-particle detector array an improved measurement of the delayed proton spectrum was possible. Protons with energy up to more than 12 MeV are measured and the corresponding log(ft) values extracted. A revised decay scheme is constructed. The connection to molecular states and the shell model is discussed.

High-precision mass measurement ofS31with the double Penning trap JYFLTRAP improves the mass value forCl32

2010

Energy of the $^{229}$Th nuclear clock transition

2019

The first nuclear excited state of $^{229}$Th offers the unique opportunity for laser-based optical control of a nucleus. Its exceptional properties allow for the development of a nuclear optical clock which offers a complementary technology and is expected to outperform current electronic-shell based atomic clocks. The development of a nuclear clock was so far impeded by an imprecise knowledge of the energy of the $^{229}$Th nuclear excited state. In this letter we report a direct excitation energy measurement of this elusive state and constrain this to 8.28$\pm$0.17 eV. The energy is determined by spectroscopy of the internal conversion electrons emitted in-flight during the decay of the …

Internal conversion from excited electronic states of 229Th ions

2017

The process of internal conversion from excited electronic states is investigated theoretically for the case of the vacuum-ultraviolet nuclear transition of 229Th. Due to the very low transition energy, the 229Th nucleus offers the unique possibility to open the otherwise forbidden internal conversion nuclear decay channel for thorium ions via optical laser excitation of the electronic shell. We show that this feature can be exploited to investigate the isomeric state properties via observation of internal conversion from excited electronic configurations of Th+ and Th2+ ions. A possible experimental realization of the proposed scenario at the nuclear laser spectroscopy facility IGISOL in J…

The SAGE spectrometer: A tool for combined in-beam gamma-ray and conversion electron spectroscopy

2010

International audience; The sage spectrometer allows simultaneous in-beam -ray and internal conversion electron measurements, by combining a germanium detector array with a highly segmented silicon detector and an electron transport system. sage is coupled with the ritu gas- lled recoil separator and the great focal-plane spectrometer for recoil-decay tagging studies. Digital electronics are used both for the ray and the electron parts of the spectrometer. sage was commissioned in the Accelerator Laboratory of the University of Jyvaskyla in the beginning of 2010.

Combined in-beam gamma-ray and conversion electron spectroscopy with radioactive ion beams. Simulations of a silicon detector for the SPEDE spectrome…

2013

In-beam gamma-ray and electron spectroscopy have been widely used as tools to study the broad variety of phenomena in nuclear structure. The SPEDE spectrometer is a new device to be used in conjunction with the MINIBALL germanium detector array to enable the detection of internal conversion electrons in coincidence with gamma rays from de-exciting nuclei in radioactive ion beam experiments at the upcoming HIE-ISOLDE facility at CERN, Switzerland. Geant4 simulations were carried out in order to optimise the design and segmentation of the silicon detector to achieve good energy resolution and performance. ispartof: pages:1-4 ispartof: EPJ Web ofConferences vol:63 pages:1-4 ispartof: Heavy Ion…

Combined in-beam electron andγ-ray spectroscopy ofHg184,186

2011

By exploiting the SAGE spectrometer a simultaneous measurement of conversion electrons and {gamma} rays emitted in the de-excitation of excited levels in the neutron-deficient nuclei {sup 184,186}Hg was performed. The light Hg isotopes under investigation were produced using the 4n channels of the fusion-evaporation reactions of {sup 40}Ar and {sup 148,150}Sm. The measured K- and L-conversion electron ratios confirmed the stretched E2 nature of several transitions of the yrast bands in {sup 184,186}Hg. Additional information on the E0 component of the 2{sub 2}{sup +}{yields}2{sub 1}{sup +} transition in {sup 186}Hg was obtained.

Isomeric and ground-state properties of78171Pt,76167Os, and74163W

2010

Decay paths, half-lives, and excitation energies of the i(13/2) bandheads of the neutron-deficient nuclei Pt-171, Os-167, and W-163 have been established for the first time. Gamma-ray transitions, ...

Beta decay of 108Mo and of neighbouring even Mo-isotopes

1995

Abstract A combination of the proton-induced fission of 238 U and the on-line mass separation based on the ion-guide technique has been applied in the study of neutron-rich Mo-isotopes. The decays of 106,108 Mo have been studied by using gamma-, beta-, X-ray and conversion-electron spectroscopy. The decay scheme of 106 Mo has been revised and a beta-decay half-life of 8.73(12) s has been measured for this nucleus. A beta-decay half-life of 1.09(2) s and a decay energy of 5120(40) keV have been measured for 108 Mo. The decay scheme of 108 Mo has been constructed and altogether 29 new transitions have been placed in the decay scheme. The beta-decay strengths of 102,104,106,108 Mo have been de…

Decay of aπh11/2⊗νh11/2microsecond isomer in61136Pm75

2008

An experiment has been performed to populate several extremely neutron-deficient nuclei around the mass-140 region of the nuclear chart, using a beam of {sup 54}Fe on a {sup 92}Mo target at an energy of 315 MeV. Analysis of these data using recoil-isomer tagging has established that the yrast {pi}h{sub 11/2} x {nu}h{sub 11/2},J{sup {pi}}=(8{sup +}), bandhead state in {sup 136}Pm is isomeric with a half-life of 1.5(1) {mu}s. This isomeric state decays via a 43-keV, probable-E1 transition to a J{sup {pi}}=(7{sup -}) state. Consideration of the theoretical Nilsson orbitals near the Fermi surface suggests that the J{sup {pi}}=(8{sup +}) state has a {nu}h{sub 11/2}[505](11/2){sup -} x {pi}h{sub …