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arXiv · 1611.07361

The Peak Structure in the In-Flight ${}^{3}\text{He} ( K^{-} , \, Λp ) n$ Reaction Around the $\bar{K} N N$ Threshold

Takayasu Sekihara·Eulogio Oset·Angels Ramos
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Abstract

We theoretically investigate the origin of the peak structure around the $K^{-} p p$ threshold observed in the in-flight ${}^{3}\text{He} ( K^{-} , \, Λp ) n$ reaction in the recent E15 experiment at J-PARC. For this purpose, we consider two scenarios to produce the peak. One is that the $Λ(1405)$ is generated but it does not correlate with $p$, and the uncorrelated $Λ(1405) p$ system subsequently decays into $Λp$. The other one is that the $\bar{K} N N$ bound state is indeed generated and decays into $Λp$. As a result, the experimental signal is qualitatively well reproduced in the $\bar{K} N N$ bound scenario, definitely discarding the uncorrelated $Λ(1405) p$ one.

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Takayasu Sekihara, Eulogio Oset, Angels Ramos. 2016-11-21. The Peak Structure in the In-Flight ${}^{3}\text{He} ( K^{-} , \, Λp ) n$ Reaction Around the $\bar{K} N N$ Threshold. https://doi.org/10.7566/jpscp.13.020002

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