Evidence for ${χ_{b}}^{'}$ Production in the Exclusive Reaction $ϒ^{''} \to γ {χ_{b}}^{'} \to (γ γ ϒ^{'} or γ γ ϒ)$

Evidence is presented for the production of

{χ_{b}}^{'}

states (

2 {}^{3}P

) in the reaction

ϒ^{''} \to γ {χ_{b}}^{'} \to γ γ ϒ^{'} (or γ γ ϒ)

with subsequent decay of the

ϒ^{'} (ϒ)

into

e^{+} e^{-}

μ^{+} μ^{-}

. The data were obtained with the nonmagnetic CUSB detector at the Cornell

e^{+} e^{-}

storage ring. Observed were 14 (15) events consistent with the transition to the

ϒ^{'} (ϒ)

with an estimated background of 1.7 (1.3) events. The lower-energy photons cluster around 100 MeV, implying

M (ϒ^{''}) - M ({χ_{b}}^{'}) \sim 100

MeV. A single-line interpretation of the lower-energy photon spectrum is disfavored.

This publication has 5 references indexed in Scilit:

Evidence for χb′ Production in the Exclusive Reaction ϒ′′→γχb′→(γγϒ′ or γγϒ)