Observation of a New D_s Meson Decaying to D K at a Mass of 2.86 GeV/c^2

TL;DR

This paper reports the discovery of a new D_s meson at 2.86 GeV/c^2 decaying into D K, based on analysis of 240 fb^-1 of data from the BaBar detector, expanding the understanding of meson spectroscopy.

Contribution

First observation of a new D_s meson at 2.86 GeV/c^2 decaying into D K, providing new insights into meson states and their properties.

Findings

New D_s meson observed at 2.86 GeV/c^2

Measured width of the new meson is 48 MeV

A broad structure at 2.69 GeV/c^2 also observed

Abstract

We observe a new D_s meson with mass (2856.6 +/- 1.5_{stat.} +/- 5.0_{syst.}) MeV/c^2 and width (48 +/- 7_{stat.} +/- 10_{syst.}) MeV decaying into D^0 K^+ and D^+K^0_S. In the same mass distributions we also observe a broad structure with mass (2688 +/- 4_{stat.} +/- 3_{syst.}) MeV/c^2 and width (112 +/- 7_{stat.} +/- 36_{syst.}) MeV. To obtain this result we use 240 fb^-1 of data recorded by the BaBar detector at the PEP-II asymmetric-energy e^+e^- storage rings at the Stanford Linear Accelerator Center running at center-of-mass energies near 10.6 GeV.