Fine structure of the Gamow-Teller resonance in 90Nb and level density of 1+ states.

The fine structure of the Gamow-Teller resonance in a medium-heavy nucleus is observed for the first time in a high-resolution 90Zr(3He,t)90Nb experiment at the Research Center for Nuclear Physics, Osaka. Using a novel wavelet analysis technique, it is possible to extract characteristic energy scales and to quantify their relative importance for the generation of the fine structure. This method combined with the selectivity of the reaction permits an extraction of the level density of 1+ states in 90Nb.

[1]  G. Mitchell,et al.  Parity dependence of 45Sc level densities , 2004 .

[2]  F D Smit,et al.  Fine structure in the energy region of the isoscalar giant quadrupole resonance: characteristic scales from a wavelet analysis. , 2004, Physical review letters.

[3]  Y. Alhassid,et al.  Influence of parity-dependence in the nuclear level density on the prediction of astrophysical reaction rates , 2003, nucl-th/0302045.

[4]  K. Hara,et al.  Realization of matching conditions for high-resolution spectrometers , 2002 .

[5]  A. Richter,et al.  Giant resonance spectroscopy of 40Ca with the (e,e′x) reaction (I): Experiments and overview of results , 2001 .

[6]  Stéphane Goriely,et al.  Microscopic nuclear level densities for practical applications , 2001 .

[7]  K. Langanke,et al.  Nuclear Reactions and Stellar Processes , 2001 .

[8]  A. Woude,et al.  Giant Resonances: Fundamental High-Frequency Modes of Nuclear Excitation , 2001 .

[9]  D. Roberts,et al.  Direct and statistical proton decay from isovector giant resonances in 90Nb , 2001 .

[10]  K. Schweda,et al.  Giant resonances in the doubly magic nucleus 48Ca from the (e, e'n) reaction. , 2000, Physical review letters.

[11]  Bertsch,et al.  Parity dependence of nuclear level densities , 1999, Physical review letters.

[12]  Reitz,et al.  Magnetic quadrupole resonances in 48Ca and 90Zr from 180° electron scattering , 1998 .

[13]  F. Thielemann,et al.  Nuclear level density and the determination of thermonuclear rates for astrophysics , 1996, astro-ph/9602087.

[14]  A. Richter,et al.  Applications of Statistical Nuclear-Physics to Nuclear Spectroscopy , 1990 .

[15]  R. Bergère.  Features of the giant E I - resonances , 1977 .