Speaker
Description
In this talk I will discuss how one can be more differential in
event-shape distributions by measuring the angle defined by the thrust axis
and the beam. As was shown in an earlier publication, the angular
dependence can be parametrised in terms of the well-known angular-averaged
cross section and the so called “angular” distribution. I will show that,
even though for jets initiated by light quarks the angular distribution
starts at O(alphaS), quark mass effects bring a non-vanishing contribution
already at at O(alphaS^0), making it a potential candidate for precision
measurements with flavour-tagged jets, and an important correction to the
massless limit. In the rest of the talk I will show how to setup the NLO
computation, highlighting how to analytically cancel the IR divergences
when adding up real- and virtual-radiation contributions, and show our
results. We find a universal coefficient for the plus function, a closed
integral form for the delta coefficient and a numerical result for the
non-singular terms that can be computed with high precision.
