A simulation study on the measurement of D0-D0bar mixing parameter y at BES-III

TL;DR

This paper proposes a method to measure the D0-D0bar mixing parameter y at BESIII using doubly tagged events and particle identification techniques, estimating a sensitivity of 0.007 with simulated data.

Contribution

It introduces a novel measurement approach for the mixing parameter y at BESIII, combining CP-eigenstate and semileptonic decays with advanced particle ID methods.

Findings

Estimated measurement sensitivity of y as 0.007

Method demonstrated using fully simulated MC data

Utilizes combined detector information for particle identification

Abstract

We established a method on measuring the $\dzdzb$ mixing parameter $y$ for BESIII experiment at the BEPCII $e^+e^-$ collider. In this method, the doubly tagged $\psi(3770) \to D^0 \overline{D^0}$ events, with one $D$ decays to CP-eigenstates and the other $D$ decays semileptonically, are used to reconstruct the signals. Since this analysis requires good $e/\pi$ separation, a likelihood approach, which combines the $dE/dx$, time of flight and the electromagnetic shower detectors information, is used for particle identification. We estimate the sensitivity of the measurement of $y$ to be 0.007 based on a $20fb^{-1}$ fully simulated MC sample.