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arXiv · nucl-ex/0505007

Investigation of the 6He cluster structures

Abstract

The 4He+2n and t+t clustering of the 6He ground state were investigated by means of the transfer reaction 6He(p,t)4He at 25 MeV/nucleon. The experiment was performed in inverse kinematics at GANIL with the SPEG spectrometer coupled to the MUST array. Experimental data for the transfer reaction were analyzed by a DWBA calculation including the two neutrons and the triton transfer. The couplings to the 6He --> 4He + 2n breakup channels were taken into account with a polarization potential deduced from a coupled-discretized-continuum channels analysis of the 6He+1H elastic scattering measured at the same time. The influence on the calculations of the 4He+t exit potential and of the triton sequential transfer is discussed. The final calculation gives a spectroscopic factor close to one for the 4He+2n configuration as expected. The spectroscopic factor obtained for the t+t configuration is much smaller than the theoretical predictions.

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L. Giot, P. Roussel-Chomaz, C. E. Demonchy, W. Mittig, H. Savajols, N. Alamanos, F. Auger, A. Gillibert, C. Jouanne, V. Lapoux, L. Nalpas, E. C. Pollacco, J. L. Sida, F. Skaza, M. D. Cortina-Gil, J. Fernandez-Vasquez, R. S. Mackintosh, A. Pakou, S. Pita, A. Rodin, S. Stepantsov, G. M. Ter Akopian, K. Rusek, I. J. Thompson, R. Wolski. 2005-05-04. Investigation of the 6He cluster structures. https://doi.org/10.1103/physrevc.71.064311

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