A precise determination of alpha_s from LEP thrust data using effective field theory

Understand

Starting from a factorization theorem in Soft-Collinear Effective Theory, the thrust distribution in e+e- collisions is calculated including resummation of the next-to-next-to-next-to leading logarithms.

• This is a significant improvement over previous calculations which were only valid to next-to-leading logarithmic order.
• The fixed-order expansion of the resummed result approaches the exact fixed-order distribution towards the kinematic endpoint.
• This close agreement provides a verification of both the effective field theory expression and recently completed next-to-next-to-leading fixed order event shapes.