Search for Time-Dependent CP Violation in D^{0}→π^{+}π^{-}π^{0} Decays

Area of Science:

• Particle Physics
• High Energy Physics
• Quantum Chromodynamics

Background:

• CP violation is a key phenomenon in particle physics, crucial for understanding matter-antimatter asymmetry.
• The D0 meson system provides a unique laboratory for studying CP violation due to its rich decay modes.

Purpose of the Study:

• To measure time-dependent CP violation in D0→π+π-π0 decays.
• To test the Standard Model predictions for CP symmetry in the charm sector.
• To constrain new physics scenarios beyond the Standard Model.

Main Methods:

• Utilized a large dataset of proton-proton collisions from the LHCb experiment (2012, 2015-2018).
• Determined the initial flavor of D0 candidates via the D*(2010)+→D0π+ decay.
• Employed D0→K-π+π0 as a control channel to validate the measurement techniques.

Main Results:

• Measured the gradient of the time-dependent CP asymmetry, ΔY, in D0→π+π-π0 decays.
• Obtained ΔY = (-1.3 ± 6.3 ± 2.4) × 10^{-4}.
• The result is statistically compatible with the hypothesis of CP conservation.

Conclusions:

• The measurement provides strong evidence for CP conservation in D0→π+π-π0 decays.
• This finding contributes to the precise testing of the Standard Model in the charm sector.
• Further studies with increased luminosity may improve sensitivity to CP violation.