45540139
Precise study of the final-state continua in 8 Li and 8 B decays
We studied β-delayed singles-α spectra from 8Li and 8B decays with special emphasis on a careful calibration of the energy scale. 8Li and 8B activities were produced by 7Li(d, p) and 6Li(3He,n) reactions, respectively, and deposited in thin C foils. Delayed α’s were counted in thin, cooled Si detectors with small solid angles to reduce summing with β’s. The energy scale and detector response were calibrated with spectroscopic grade radioactive sources. We extracted the 8Li and 8B final-state continuum shapes from our spectra by using R-matrix analyses that included effects of lepton-recoil broadening and detector response. Our results are in excellent agreement with a recent measurement using 8B’s implanted in a Si counter and in good agreement with our reanalysis of the older Wilkinson-Alburger 8Li and 8B data, but disagree with a recent 8B experiment using a coincidence technique.
121755167
Electron capture decay of In-116 and nuclear structure of double beta decays
Quasiparticle-random-phase-approximation (QRPA) calculations of double {beta} decays have not been able to reproduce data in the A=100 system. We propose the A=116 system{emdash}because of its smaller deformation{emdash}as a simpler system to test QRPA calculations. We present results of two experiments we performed, which determine the electron-capture-decay branch of {sup 116}In to be (2.27{plus_minus}0.63){times}10{sup {minus}2}{percent}, from which we deduce logft=4.39{sub {minus}0.15}{sup +0.10}. We present QRPA calculations and compare their predictions to experimental data. Finally we use these calculations to predict the 2{nu} double-{beta}-decay rate of {sup 116}Cd to the ground and excited states of {sup 116}Sn. {copyright} {ital 1998} {ital The American Physical Society}
3205210
Correction to Relativistic Mean Field binding energy and NpNn scheme
Abstract The differences between the experimental and Relativistic Mean Field binding energies have been calculated for a large number of even–even nuclei from A = 50 to 220. Excluding certain mass regions, the differences, after suitable corrections for particular isotope chains, are found to be proportional to the Casten factor P, chosen as a measure of n – p interaction strength in a nucleus. Results for even-Z odd-N nuclei are also seen to follow the same relation, if the odd–even mass difference is taken into account following the semiempirical formula. This indicates that the n – p interaction is the major contributor to the difference between the calculated and the experimental binding energies.
124431237
Massive neutron stars with a hyperonic core: A case study with the IUFSU relativistic effective interaction
The recent discoveries of massive neutron stars, such as PSR J0348 + 0432 and PSR J1614–2230, have raised questions about the existence of exotic matter such as hyperons in the neutron star core. The validity of many established equations of states (EoSs) like GM1 and FSUGold are also questioned. We investigate the existence of hyperonic matter in the central regions of massive neutron stars by using relativistic mean field (RMF) theory with the recently proposed Indiana University Florida State University (IUFSU) model. The IUFSU model is extended by including hyperons to study the neutron star in β equilibrium. The effect of different hyperonic