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arXiv · 1702.06100

Off-shell persistence of composite pions and kaons

Si-Xue Qin·Chen Chen·Cedric Mezrag·Craig D. Roberts
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Abstract

In order for a Sullivan-like process to provide reliable access to a meson target as $t$ becomes spacelike, the pole associated with that meson should remain the dominant feature of the quark-antiquark scattering matrix and the wave function describing the related correlation must evolve slowly and smoothly. Using continuum methods for the strong-interaction bound-state problem, we explore and delineate the circumstances under which these conditions are satisfied: for the pion, this requires $-t \lesssim 0.6\,$GeV$^2$, whereas $-t\lesssim 0.9\,$GeV$^2$ will suffice for the kaon. These results should prove useful in evaluating the potential of numerous experiments at existing and proposed facilities.

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Si-Xue Qin, Chen Chen, Cedric Mezrag, Craig D. Roberts. 2017-02-20. Off-shell persistence of composite pions and kaons. https://doi.org/10.1103/physrevc.97.015203

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