Improved Measurement of Absolute Hadronic Branching Fractions of the Ds+ Meson

TL;DR

This paper presents precise measurements of absolute branching fractions for 13 Ds meson decays using a large dataset, improving the accuracy of charm quark process normalization and exploring CP violation.

Contribution

It provides the first precise measurements of several Ds decay branching fractions and resolves discrepancies in previous measurements, enhancing understanding of charm quark decays.

Findings

Precise measurement of B(Ds -> K- K+ pi+) = (5.55 +- 0.14 +- 0.13)%

Reduced value of B(Ds -> pi+ pi0 eta') compared to previous data

Measured cross-section of e+ e- -> Ds* Ds at 4.17 GeV

Abstract

The branching fractions of Ds meson decays serve to normalize many measurements of processes involving charm quarks. Using 586 pb^-1 of e+ e- collisions recorded at a center of mass energy of 4.17 GeV, we determine absolute branching fractions for 13 Ds decays in 16 reconstructed final states with a double tag technique. In particular we make a precise measurement of the branching fraction B(Ds -> K- K+ pi+) = (5.55 +- 0.14 +- 0.13)%, where the uncertainties are statistical and systematic respectively. We find a significantly reduced value of B(Ds -> pi+ pi0 eta') compared to the world average, and our results bring the inclusively and exclusively measured values of B(Ds -> eta' X)$ into agreement. We also search for CP-violating asymmetries in Ds decays and measure the cross-section of e+ e- -> Ds* Ds at Ecm = 4.17 GeV.