13 research outputs found
Results from Shell Model Monte Carlo Studies
We review results obtained using Shell Model Monte Carlo (SMMC) techniques.
These methods reduce the imaginary-time many-body evolution operator to a
coherent superposition of one-body evolutions in fluctuating one-body fields;
the resultant path integral is evaluated stochastically. After a brief review
of the methods, we discuss a variety of nuclear physics applications. These
include studies of the ground-state properties of pf-shell nuclei, Gamow-Teller
strength distributions, thermal and rotational pairing properties of nuclei
near N=Z, -soft nuclei, and -decay in ^{76}Ge. Several
other illustrative calculations are also reviewed. Finally, we discuss
prospects for further progress in SMMC and related calculations
Descritpion of Exotic Nuclei Using Continuum Shell Model
In weakly bound exotic nuclei, number of excited bound states or narrow
resonances is small and, moreover, they couple strongly to the particle
continuum. Hence, these systems should be described in the quantum open system
formalism which does not artificially separate the subspaces of (quasi-) bound
and scattering states. The Shell Model Embedded in the Continuum provides a
novel approach which solves this problem. Examples of application in sd-shell
nuclei will be presented.Comment: Presented at the NATO Advanced Research Workshop Brijuni, Pula,
Croatia, June 2-5, 200
Isomer and decay studies for the rp process at IGISOL
This article reviews the decay studies of neutron-deficient nuclei within the mass region \ensuremath A=56\mbox{--}100 performed at the Ion-Guide Isotope Separator On-Line (IGISOL) facility in the University of Jyväskylä over last 25 years. Development from He-jet measurements to on-line mass spectrometry, and eventually to atomic mass measurements and post-trap spectroscopy at IGISOL, has yielded studies of around 100 neutron-deficient nuclei over the years. The studies form a solid foundation to astrophysical rp -process path modelling. The focus is on isomers studied either via spectroscopy or via Penning-trap mass measurements. The review is complemented with recent results on the ground and isomeric states of 90Tc . The excitation energy of the low-spin isomer in 90Tc has been measured as \ensuremath E_x=144.1(17) keV with JYFLTRAP double Penning trap and the ground state of 90Tc has been confirmed to be the (8+) state with a half-life of \ensuremath T_{1/2}=49.2(4) s. Finally, the mass-excess results for the spin-gap isomers 53Co
m
and 95Pd
m
and implications from the JYFLTRAP mass measurements for the (21+) isomer in 94Ag are discussed