Abstract
The parton splittings in a parton shower are ordered according to an ordering variable, for example the transverse momentum of the daughter partons relative to the direction of the mother, the virtuality of the splitting, or the angle between the daughter partons. We analyze the choice of the ordering variable and conclude that one particular choice has the advantage of factoring softer splittings from harder splittings graph by graph in a physical gauge.
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The code is available at Deductor: a parton shower event generator webpage, http://www.desy.de/∼znagy/deductor and http://pages.uoregon.edu/soper/deductor/.
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Nagy, Z., Soper, D.E. Ordering variable for parton showers. J. High Energ. Phys. 2014, 178 (2014). https://doi.org/10.1007/JHEP06(2014)178
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DOI: https://doi.org/10.1007/JHEP06(2014)178