Roper excitation in the pp → ppπ 0 reaction close to threshold
نویسنده
چکیده
A new mechanism for the pp → ppπ reaction close to threshold is suggested coming from the isoscalar excitation of the Roper and its decay into N(ππ)s−wave, with one of the π 0 emitted and the other one reabsorbed on the second nucleon. The mechanism can lead to important interference with other mechanisms and, together with experiment, serves to exclude large ranges of the 2π N decay parameters allowed by the N partial decay widths.
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