Oriented Event Shapes

por Vicent Mateu (IFIC)

miércoles 31 jul. 2013 15:30 → 16:30 Europe/Madrid

1001-Primera-1-1-1 - Paterna. Seminario (Universe)

Oriented event-shapes are distributions of event-shape variables which are differential on the angle that the thrust axis forms with the electron-positron beam. We analyze these distributions in the context of SCET and in Fixed-Order perturbation theory. We show that at any order in perturbation theory and for any event-shape, only two angular structures can appear. The validity of our proof goes beyond perturbation theory, and hence only these two structures are present at the hadron level. The proof also carries over massive particles. Using SCET techniques we show that singular terms can only arise in one of these two terms.