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تسجيل مستخدم جديد$Xi^- t$ quasibound state instead of $LambdaLambda nn$ bound state
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We study the coupled $LambdaLambda nn-Xi^- pnn$ system to check whether the inclusion of channel coupling is able to bind the $LambdaLambda nn$ system. We use a separable potential three-body model of the coupled $LambdaLambda nn - Xi^- pnn$ system as well as a variational four-body calculation with realistic interactions. Our results exclude the possibility of a $LambdaLambda nn$ bound state by a large margin. However, we have found a $Xi^- t$ quasibound state above the $LambdaLambda nn$ threshold.
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We use an existing model of the $LambdaLambda N - Xi NN$ three-body system based in two-body separable interactions to study the $(I,J^P)=(1/2,1/2^+)$ three-body channel. For the $LambdaLambda$, $Xi N$, and $LambdaLambda - Xi N$ amplitudes we have co
nstructed separable potentials based on the most recent results of the HAL QCD Collaboration. They are characterized by the existence of a resonance just below or above the $Xi N$ threshold in the so-called $H$-dibaryon channel, $(i,j^p)=(0,0^+)$. A three-body resonance appears {2.3} MeV above the $Xi d$ threshold. We show that if the $LambdaLambda - Xi N$ $H$-dibaryon channel is not considered, the $LambdaLambda N - Xi NN$ $S$ wave resonance disappears. Thus, the possible existence of a $LambdaLambda N - Xi NN$ resonance would be sensitive to the $LambdaLambda - Xi N$ interaction. The existence or nonexistence of this resonance could be evidenced by measuring, for example, the $Xi d$ cross section.
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