Measurement of masses and widths of excited charm mesons D-2(*) and evidence for broad states

摘要

Using data from the FOCUS experiment we analyze the D(+)pi(-) and D(0)pi(+) invariant mass distributions. We measure the D-2(*0) mass M-D2*0 (2464.5 +/- 1.1 +/- 1.9) MeV/c(2) and width GammaD(2*0) = (38.7 +/- 5.3 +/- 2.9) MeV/c(2) and the D-2(*+) mass MD2*+ = (2467.6 +/- 1.5 +/- 0.76) MeV/c(2) and width GammaD(2*+) = (34.1 +/- 6.5 +/- 4.2) MeV/c(2). We find evidence for broad structures over background in both the neutral and charged final state. If each is interpreted as evidence for a single L = 1, j(q) = 1/2 excited charm meson resonance, the masses and widths are M-1/2(0) (2407 +/- 21 +/- 35) MeV/c(2), Gamma(1/2)(0) (240 +/- 55 +/- 59) MeV/c(2) M-1/2(+) = (2403 +/- 14 +/- 35) MeV/c(2), Gamma(1/2)(+) = (283 +/- 24 +/- 34) MeV/c(2), respectively. (C) 2004 Published by Elsevier B.V.