Observation of a New Excited Ds+ Meson in B0 → D- D+ K+ π- Decays

Using pp collision data corresponding to an integrated luminosity of 5.4 fb(-1) collected with the LHCb detector at a center-of-mass energy of 13 TeV, the B-0 -> D- D+ K+ pi(-) decay is studied. A new excited D-s(+) meson is observed decaying into the D+K+pi(-) final state with large statistical significance. The pole mass and width, and the spin parity of the new state are measured with an amplitude analysis to be m(R) = 2591 +/- 6 +/- 7 MeV, Gamma(R) = 89 +/- 16 +/- 12 MeV, and J(P) = 0(-), where the first uncertainty is statistical and the second systematic. Fit fractions for all components in the amplitude analysis are also reported. The new resonance, denoted as D-s0(2590)(+), is a strong candidate to be the D-s(2(1)S(0))(+) state, the radial excitation of the pseudoscalar ground-state D-s(+) meson.

Automated summary

Using data from pp collisions collected with the LHCb detector corresponding to an integrated luminosity of 5.4 fb(-1) at a center-of-mass energy of 13 TeV, a new excited state D-s0(2590)(+) decaying into the D+K+pi(-) final state is observed with significant statistical significance. The mass, width, and spin parity of the new state are measured with an amplitude analysis to be m(R) = 2591 +/- 6 +/- 7 MeV, Gamma(R) = 89 +/- 16 +/- 12 MeV, and J(P) = 0(-), respectively. The new resonance is a strong candidate to be the radial excitation of the pseudoscalar ground-state D-s(+) meson, denoted as D-s(2(1)S(0))(+).