Threshold effect and \pi^\pm \psi(2S) peak

Abstract

A resonance-like structure in the ${\pi }^{\pm }\psi (2S)$ mass spectrum arising in $B\to K{\pi }^{\pm }\psi (2S)$ has recently been reported. It is noted that the mass of this structure, $4433\pm 4\pm 1$ MeV, is not far from the threshold for production of $D^{\ast }{\bar{D}}_1(2420)$. A proposed mechanism for production of this state is suggested, and tests are suggested.

Comments: 4 pages, 1 figure. To be submitted to Phys. Rev. D (Brief Reports). Additional text, acknowledgment, references; note added on other work