Nonmesonic Weak Decay Spectra and Three-Nucleon Emission

Abstract

We have evaluated the nonmesonic weak decay spectra within the independent-particle shell-model, and compared them with the recent measurements of: i) the single and double coincidence nucleon spectra in ${}_{\mathrm{\Lambda }}^{12}\mathrm{C}$ performed at KEK, and ii) proton kinetic energy spectra in ${}_{\mathrm{\Lambda }}^5\mathrm{He}$, ${}_{\mathrm{\Lambda }}^7\mathrm{Li}$, ${}_{\mathrm{\Lambda }}^9\mathrm{Be}$, ${}_{\mathrm{\Lambda }}^{11}\mathrm{B}$, ${}_{\mathrm{\Lambda }}^{12}\mathrm{C}$, ${}_{\mathrm{\Lambda }}^{13}\mathrm{C}$, ${}_{\mathrm{\Lambda }}^{15}\mathrm{N}$ and ${}_{\mathrm{\Lambda }}^{16}\mathrm{O}$ done by FINUDA. Based on this comparison we argue that the extraction from the data of the three-body $\Lambda NN\to nNN$ induced decay rate, as done in these works, could be questionable.

Comments: 15 pages, 8 figures