Building a consistent parton shower

Understand

Modern parton showers are built using one of two models: dipole showers or angular ordered showers.

• Both have distinct strengths and weaknesses.
• Dipole showers correctly account for wide-angle, soft gluon emissions and track the leading flows in QCD colour charge but they are known to mishandle partonic recoil.
• Angular ordered showers keep better track of partonic recoil and correctly include large amounts of wide-angle, soft physics but azimuthal averaging means they are known to mishandle some correlations.