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arXiv · 1110.1586

Level density of 2+ states in 40Ca from high energy-resolution (p,p') experiments

I. Usman·Z. Buthelezi·J. Carter·G. R. J. Cooper·R. W. Fearick·S. V. Förtsch·H. Fujita·Y. Kalmykov·P. von Neumann-Cosel·R. Neveling·I. Poltoratska·A. Richter·A. Shevchenko·E. Sideras-Haddad·F. D. Smit·J. Wambach
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Abstract

The level density of 2+ states in 40Ca has been extracted in the energy region of the isoscalar giant quadrupole resonance (ISGQR) from a fluctuation analysis of high energy-resolution p,p') data taken at incident energies of 200 MeV at the K600 magnetic spectrometer of iThemba LABS, South Africa. Quasi-free scattering cross sections were calculated to estimate their role as a background contribution to the spectra and found to be small. The shape of the background was determined from the discrete wavelet transform of the spectra using a biorthogonal wavelet function normalized at the lowest particle separation threshold. The experimental results are compared to widely used phenomenological and microscopic models.

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I. Usman, Z. Buthelezi, J. Carter, G. R. J. Cooper, R. W. Fearick, S. V. Förtsch, H. Fujita, Y. Kalmykov, P. von Neumann-Cosel, R. Neveling, I. Poltoratska, A. Richter, A. Shevchenko, E. Sideras-Haddad, F. D. Smit, J. Wambach. 2011-11-09. Level density of 2+ states in 40Ca from high energy-resolution (p,p') experiments. https://doi.org/10.1103/physrevc.84.054322

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