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A high-energy-resolution Be-9(He-3,t)B-9 charge-exchange reaction was performed around a scattering angle of 0 degrees. and at an intermediate incident energy of 140 MeV/ nucleon for the study of precise Gamow-Teller (GT) transition strengths. The energy resolution of 30 keV allowed a precise deconvolution of the spectrum and the determination of angular distributions of cross sections, excitation energies, and decay widths. The GT strength of 10 states has been determined for the first time using the GT strength of the analogous beta decays of Li-9 and C-9 as standards. The large difference between the GT strengths going to the low-lying T = 1/ 2 and the highly excited T = 3/ 2 states is interpreted as a result of their different spatial structures. The obtained GT strength distribution is compared to the results of a (p, n) experiment with lower resolution performed in the 1980s. In particular, the width of the 16.8 MeV, J(pi) = (5/2(+)) state has been determined for the first time.

A high-energy-resolution Be-9(He-3,t)B-9 charge-exchange reaction was performed around a scattering angle of 0 degrees. and at an intermediate incident energy of 140 MeV/ nucleon for the study of precise Gamow-Teller (GT) transition strengths. The energy resolution of 30 keV allowed a precise deconvolution of the spectrum and the determination of angular distributions of cross sections, excitation energies, and decay widths. The GT strength of 10 states has been determined for the first time using the GT strength of the analogous beta decays of Li-9 and C-9 as standards. The large difference between the GT strengths going to the low-lying T = 1/ 2 and the highly excited T = 3/ 2 states is interpreted as a result of their different spatial structures. The obtained GT strength distribution is compared to the results of a (p, n) experiment with lower resolution performed in the 1980s. In particular, the width of the 16.8 MeV, J(pi) = (5/2(+)) state has been determined for the first time.

A high-energy-resolution Be-9(He-3,t)B-9 charge-exchange reaction was performed around a scattering angle of 0 degrees. and at an intermediate incident energy of 140 MeV/ nucleon for the study of precise Gamow-Teller (GT) transition strengths. The energy resolution of 30 keV allowed a precise deconvolution of the spectrum and the determination of angular distributions of cross sections, excitation energies, and decay widths. The GT strength of 10 states has been determined for the first time using the GT strength of the analogous beta decays of Li-9 and C-9 as standards. The large difference between the GT strengths going to the low-lying T = 1/ 2 and the highly excited T = 3/ 2 states is interpreted as a result of their different spatial structures. The obtained GT strength distribution is compared to the results of a (p, n) experiment with lower resolution performed in the 1980s. In particular, the width of the 16.8 MeV, J(pi) = (5/2(+)) state has been determined for the first time.

The Gamow-Teller (GT) transition strengths in fp-shell nuclei are important parameters in presupernova models. A high-energy-resolution (He-3,t) experiment was performed on the T-z=1 nucleus Ti-46 at 0(degrees) and at an intermediate incident energy of 140 MeV/nucleon for the study of precise GT transition strengths to the final T-z=0 nucleus V-46. With an energy resolution of 33 keV, individual GT transitions were observed and GT strengths were derived for them up to the excitation energy of 4.5 MeV. The GT strengths were compared with shell-model calculations using various effective interactions. In this low-lying region, most GT states have isospin T=0. A few GT states with isospin T=1 were identified from the existence of the corresponding (analog) M1 states in Ti-46. By comparing the GT strength with the corresponding (analogous) M1 transition strength studied in Ti-46(e,e(')) or (gamma,gamma(')) measurements, a large constructive interference of orbital and spin terms was suggested for one of these M1 transitions.

The Gamow-Teller (GT) transition strengths in fp-shell nuclei are important parameters in presupernova models. A high-energy-resolution (He-3,t) experiment was performed on the T-z=1 nucleus Ti-46 at 0(degrees) and at an intermediate incident energy of 140 MeV/nucleon for the study of precise GT transition strengths to the final T-z=0 nucleus V-46. With an energy resolution of 33 keV, individual GT transitions were observed and GT strengths were derived for them up to the excitation energy of 4.5 MeV. The GT strengths were compared with shell-model calculations using various effective interactions. In this low-lying region, most GT states have isospin T=0. A few GT states with isospin T=1 were identified from the existence of the corresponding (analog) M1 states in Ti-46. By comparing the GT strength with the corresponding (analogous) M1 transition strength studied in Ti-46(e,e(')) or (gamma,gamma(')) measurements, a large constructive interference of orbital and spin terms was suggested for one of these M1 transitions.

The Gamow-Teller (GT) transition strengths in fp -shell nuclei are important parameters in presupernova models. A high-energy-resolution ( 3 He ,t ) experiment was performed on the T z = 1 nucleus 46 Ti at 0 ◦ and at an intermediate incident energy of 140 MeV/nucleon for the study of precise GT transition strengths to the final T z = 0 nucleus 46 V. With an energy resolution of 33 keV, individual GT transitions were observed and GT strengths were derived for them up to the excitation energy of 4.5 MeV. The GT strengths were compared with shell-model calculations using various effective interactions. In this low-lying region, most GT states have isospin T = 0. A few GT states with isospin T = 1 were identified from the existence of the corresponding (analog) M 1 states in 46 Ti. By comparing the GT strength with the corresponding (analogous) M 1 transition strength studied in 46 Ti( e, e )or( γ,γ ) measurements, a large constructive interference of orbital and spin terms was suggested for one of these M 1 transitions ispartof: Physical Review C, Nuclear Physics vol:73 issue:2 status: published

Isospin symmetry is expected for the T-z=+/- 1 -> 0 isobaric analogous transitions in isobars with mass number A, where T-z is the z component of isospin T. Assuming this symmetry, strengths of analogous Gamow-Teller (GT) transitions within A=50 isobars were determined from a high energy-resolution T-z=+1 -> 0, Cr-50(He-3,t)Mn-50 study at 0 degrees in combination with the decay Q value and lifetime from the T-z=-1 -> 0, Fe-50 ->Mn-50 beta decay. This method can be applied to other pf-shell nuclei and can be used to study GT strengths of astrophysical interest.

A high energy-resolution B-11 (He-3,t)C-11 experiment was performed at 0degrees and an intermediate incident energy of 140 MeV/nucleon for the study of precise Gamow-Teller (GT) transition strengths. Two doublet states at approximate to4.5 and approximate to8.4 MeV were clearly resolved with a resolution of 45 keV. The strengths are compared with a calculation using an ab initio no-core shell model, which became available for the A=11 system recently. It was found that a calculation including a three-nucleon interaction better reproduces the observed GT transition strengths.

A high energy-resolution B-11 (He-3,t)C-11 experiment was performed at 0degrees and an intermediate incident energy of 140 MeV/nucleon for the study of precise Gamow-Teller (GT) transition strengths. Two doublet states at approximate to4.5 and approximate to8.4 MeV were clearly resolved with a resolution of 45 keV. The strengths are compared with a calculation using an ab initio no-core shell model, which became available for the A=11 system recently. It was found that a calculation including a three-nucleon interaction better reproduces the observed GT transition strengths.

A high energy-resolution B-11 (He-3,t)C-11 experiment was performed at 0degrees and an intermediate incident energy of 140 MeV/nucleon for the study of precise Gamow-Teller (GT) transition strengths. Two doublet states at approximate to4.5 and approximate to8.4 MeV were clearly resolved with a resolution of 45 keV. The strengths are compared with a calculation using an ab initio no-core shell model, which became available for the A=11 system recently. It was found that a calculation including a three-nucleon interaction better reproduces the observed GT transition strengths.