Hyperon Resonance Λ(1405) and the K⁻pp Three-Body Resonance

Abstract

We have investigated a hyperon resonace Λ(1405) and the three-body resonance "K − pp" (the simplest kaonic nuleus) by means of a coupled-channel complex scaling method (ccCSM). Using a chiral SU(3)-based potential, we have confirmed that the Λ(1405) has a double-pole structure. For an economical treatment of the three-body system of "K − pp", the ccCSM is combined with Feshbach projection. With the ccCSM+Feshbach method, we conclude that " [20][21][22][23][24][25][26][27][28][29][30] MeV. Related to the J-PARC E27 experiment searching for the "K − pp" with a deuteron target, another state of "K − pp" with quantum numbers (J π = 1 − , T = 1/2) is discussed. As a result of our calculation, we have found no resonant poles.