Top Quark Mass Calibration for Monte Carlo Event Generators.

Area of Science:

• High Energy Physics
• Quantum Chromodynamics (QCD)
• Particle Physics

Background:

• Precise top quark mass measurements are crucial in particle physics.
• Kinematic reconstruction methods determine the Monte Carlo event generator mass (m_t^MC).
• Relating m_t^MC to a fundamental field theory mass is challenging due to hadronization and parton-shower effects.

Purpose of the Study:

• To present a calibration procedure for relating m_t^MC to a field theory mass.
• To utilize hadron-level QCD predictions for observables with kinematic mass sensitivity.
• To improve the precision and theoretical understanding of top quark mass measurements.

Main Methods:

• Developed a calibration procedure using hadron-level QCD predictions.
• Performed fits of e+e- 2-jettiness calculations at NLL and NNLL orders.
• Utilized Pythia 8.205 event generator for simulations.

Main Results:

• m_t^MC was found to differ from the pole mass by 900 MeV (NLL) and 600 MeV (NNLL).
• The determined m_t^MC agrees with the MSR mass within uncertainties (m_t^MC ≃ m_{t,1 GeV}^{MSR}).
• Demonstrated a method to link MC generator masses to theoretical mass schemes.

Conclusions:

• The calibration procedure successfully relates m_t^MC to theoretical mass definitions.
• This work provides a crucial step towards more precise top quark mass determinations.
• The findings contribute to a better understanding of top quark properties and Standard Model physics.