#beta#-decay of "4"0Ti

The #beta#-decay of "4"0Ti was studied. The Fermi and Gamow-Teller strength function was deduced from the observed #beta#-delayed emission of protons and #gamma#-rays and from the measured half-life of 55(2) ms. The results are compared to shell-model predictions and are used to estimate the neutrino-capture rate of the solar-neutrino detector ICARUS. (orig.)Available from FIZ Karlsruhe / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Study of the #beta#-decays of "3"7Ca and "3"6Ca

The #beta#-delayed proton and #gamma#-ray emission of "3"7Ca and "3"6Ca was studied at the projectile fragment separator at GSI Darmstadt. In the "3"7Ga study, the #beta#-delayed #gamma#-decay was observed for the first time, and the half-life was redetermined, under essentially background-free conditions, as 181.1#+-#1.0 ms. The surprisingly high #GAMMA#_#gamma#/#GAMMA#_p values found for proton-unbound states in "3"7K drastically reduce former discrepancies between the Gamow-Teller strength value B(GT) measured in the "3"7Ca #beta#-decay and those deduced from the "3"7Cl(p, n)"3"7Ar mirror reaction. Our data provide evidence, on a level of 1.6 standard deviations, for isospin-mixing of the lowest T=3/2 level in "3"7K. In the "3"6Ca study, a complete #beta#-decay scheme, including the #beta#-delayed proton emission into the ground and first excited states of "3"5Ar as well as the #beta#-delayed #gamma#-decay, was measured for the first time. The "3"6Ca half-life was remeasured with improved accuracy to be 102#+-#2 ms. Our data exclude a 1"+ assignment for two near-threshold states in "3"6K that could be important resonances in "3"5Ar(p, #gamma#) reactions of astrophysical interest. The B(GT) distributions in "3"7","3"6Ca decays are compared to results obtained from large-scale sd shell-model calculations. (orig.)Available from FIZ Karlsruhe / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Beta-decay of "4"0Ti and "4"1Ti and implication for solar-neutrino detection

The #beta#-decay of "4"0Ti and "4"1Ti was studied by measuring the #beta#-delayed proton- and #gamma#-emission. The half-lives for "4"0Ti and "4"1Ti were determined to be 54(2) and 82(3) ms, respectively. The experimental #beta#-decay strengths are compared with shell-model calculations and results from other measurements. The integrated Gamow-Teller strengths for "4"0Ti and "4"1Ti were found to be quenched, compared to the calculations, by factors of 0.79(3) and 0.93(3), respectively. Based on the experimental "4"0Ti #beta#-decay strength, the neutrino absorption cross-section and induced neutrino event rates for "4"0Ar were determined to be 14.3(3) x 10"-"4"3 cm"2 and 9.4#+-#0.2(stat.)_-_1_._6"+"1"."3(syst.) SNU, respectively. (orig.)Available from TIB Hannover: RO 801(98-19) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Beta decay of the new isotope "1"0"1Sn

The very neutron-deficient isotope "1"0"1Sn has been produced in a "5"0Cr("5"8Ni, 2p5n) reaction and its decay has been studied for the first time. Energy and time spectra of beta-delayed protons emitted from samples that were prepared by using chemically selective ion sources of an on-line mass separator have been measured. The half-life of "1"0"1Sn was determined to be 3#+-#1 s. The results obtained are compared to theoretical predictions. (orig.)SIGLEAvailable from TIB Hannover: RO 801(94-47) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Gamow-Teller strength in the beta-decay of "3"7Ca and its implications for the detection of the solar neutrino flux

We have studied the #beta#-decay of "3"7Ca at the projectile fragment separator FRS and GSI Darmstadt. The resulting Gamow-Teller strength function B(GT) which is important for determining the detection efficiency of the Homestake mine "3"7Cl detector is significantly changed by the inclusion of previously unobserved #beta#-delayed #gamma#-rays. With the new results former discrepancies between the B(GT) values measured in the "3"7Ga #beta#-decay and those extracted from "3"7Cl(p, n)"3"7Ar reactions are drastically reduced. Additionally, our data yield evidence for an isospin-forbidden Fermi transition in the #beta#-decay of "3"7Ca. (orig.)SIGLEAvailable from TIB Hannover: RO 801(94-67) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

First spatial isotopic separation of relativistic uranium projectile fragments

Spatial isotopic separation of relativistic uranium projectile fragments has been achieved for the first time. The fragments were produced in peripheral nuclear collisions and spatially separated in-flight with the fragment separator FRS at GSI. A two-fold magnetic-rigidity analysis was applied exploiting the atomic energy loss in specially shaped matter placed in the dispersive central focal plane. Systematic investigations with relativistic projectiles ranging from oxygen up to uranium demonstrate that the FRS is a universal and powerful facility for the production and in-flight separation of monoisotopic, exotic secondary beams of all elements up to Z=92. This achievement has opened a new area in heavy-ion research and applications. (orig.)Available from TIB Hannover: RO 801(94-41) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Gamow-Teller strength in the #beta#-decay of "3"6Ca

The #beta#-decay of "3"6Ca has been studied at the projectile fragment separator at GSI Darmstadt. The Gamow-Teller strength function B(GT), deduced from the observed #beta#-delayed proton- and #gamma#-emission and from the measured half-life of 102(2) ms, is compared to results obtained from large-scale sd-shell model calculations. (orig.)SIGLEAvailable from TIB Hannover: RO 801(94-84) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Evidence for a neutron skin in "2"0N

Nuclear interaction and charge-changing cross sections were measured for 950.A MeV "2"0N, "2"0O, "2"0F, "2"0Ne, "2"0Na and "2"0Mg beams incident on a carbon target. The experimental results are compared to other data, in particular to those obtained for stable nuclei. Root mean square nuclear matter radii and upper limits of root mean square proton radii are derived from the experimental data. Evidence is presented for the existence of a neutron skin in "2"0N. (orig.)Available from FIZ Karlsruhe / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Decay studies of the neutron-deficient isotopes "1"1"4"-"1"1"8Ba

Radioactivity "1"1"4","1"1"5","1"1"6Ba [from "5"8","6"0Ni("5"8Ni, xn), E=3.5-4.3 MeV/u]; "1"1"6","1"1"7","1"1"8Ba [from "6"3Cu("5"8Ni, pxn), E=4.3-4.9 MeV/u]; Measured E_p, I_p, E_#gamma#, I_#gamma#, #gamma##gamma#-coin, T_1_/_2; deduced cross-sections. Ge, Si, scintillator detectors, on-line mass separation. (orig.)Available from TIB Hannover: RA 801(97-36) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

The beta-decay of "2"0Mg and its implications for the astrophysical rp-process

We have studied the #beta#-delayed proton and #gamma#-decay of "2"0Mg, produced by means of 95 MeV/u "2"4Mg+Ni reactions and implanted into a detector array after electromagnetic separation at GANIL. The experimental data obtained for excitation energies, #beta#-decay branching ratios, log-ft values and J"#pi#-assignments are given. No feeding has been observed to the 2646 keV state in "2"0Na, which plays an important role in the "1"9Ne(p, #gamma#)"2"0Na breakout reaction from the hot CNO cycle. A large difference of log ft values for mirror states in "2"0Na and "2"0F was found. The experimentally determined level properties, including B(GT) values, are discussed with reference to model calculations performed within the complete sd-shell space. (orig.)Available from TIB Hannover: RO 801(93-47) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman