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arXiv · 0902.3633

Searching for signatures around 1920 MeV of a $N^*$ state of three hadron nature

A. Martínez Torres·K. P. Khemchandani·Ulf-G. Meißner·E. Oset
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Abstract

We provide a series of arguments which support the idea that the peak seen in the $\gamma p \to K^+ \Lambda$ reaction around 1920 MeV should correspond to the recently predicted state of $J^P=1/2^+$ as a bound state of $K \bar{K}N$ with a mixture of $a_0(980)N$ and $f_0(980)N$ components. At the same time we propose polarization experiments in that reaction as a further test of the prediction, as well as a study of the total cross section for $\gamma p \to K^+ K^- p$ at energies close to threshold and of $d \sigma/d M_{inv}$ for invariant masses close to the two kaon threshold.

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A. Martínez Torres, K. P. Khemchandani, Ulf-G. Meißner, E. Oset. 2009-02-20. Searching for signatures around 1920 MeV of a $N^*$ state of three hadron nature. https://doi.org/10.1140/epja/i2009-10834-2

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