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K$^-$-proton scattering and the $Λ(1405)$ in dense matter

Volker Koch
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Abstract

The scattering of antikaons with nucleons is studied in the nuclear environment. Describing the $\lam$ as a $K^-$ proton bound state, we find, that due to the Pauli blocking of intermediate states, the mass of the $Λ(1405)$ is shifted upwards in energy, above the $K^-$ proton threshold and and its width is somewhat broadened. As a consequence the s-wave $K^-$--nucleon scattering length turns attractive at finite nucleon density ($ρ\geq 0.25 ρ_0$) leading to a mean field potential for the $K^-$ of about $\sim -100 \, \rm MeV$ in nuclear matter at ground state density. Consequences for Heavy Ion collisions and possible experimental checks for the structure of the $\lam$ are discussed. (Figures will be sent on request)

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Volker Koch. 1994-06-25. K$^-$-proton scattering and the $Λ(1405)$ in dense matter. https://doi.org/10.1016/0370-2693(94)91434-6

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