Search for Bottom Counterparts of X(3872) and Y(4260) via $π^+π^-Υ$

Abstract

The X(3872) and Y(4260), both discovered in $π^+π^- J/ψ$ mode, are rather unusual: $X_c\equiv X(3872)$ is very narrow, while $Y_c \equiv Y(4260)$ has large $Y_c\to π^+π^-J/ψ$ width. Many models for their composition have been suggested, but perhaps discovering their bottom counterparts could shed much light on the issue. The narrow state, $X_b$ may be searched for at the Tevatron via $p\bar p \to π^+π^-Υ+ X$, with the LHC much more promising. The state $Y_b$ can be searched for at B factories via radiative return $e^+e^- \to γ_{\rm ISR} + π^+π^-Υ$ on $Υ(5S)$, or by $e^+e^- \to π^+π^-Υ$ direct scan.