Study of a short distance top mass with a cross-section at NNLL + NNLO

We consider top-quarks produced at large energy in e+e- collisions and address the question of what top-mass can be measured from reconstruction. The production process is characterized by the center-of-mass energy, Q, the top mass, m, the top decay width, It, and also AQCD. These scales are well separated and can be disentangled with effective theory methods such as the Heavy-Quark Effective Theory and Soft-Collinear Effective Theory. We compute a top mass observable for future e+e- colliders to next-to-next-to-leading-logarithmic order + [Omicron] [alpha] 2/[sigma](NNLL+NNLO), which goes beyond previous next-to-leading-logarithmic + [Omicron] [alpha] 2/[sigma] (NLL+NLO) analysis. We use the two-loop heavy quark jet-function, [Omicron] [alpha] 2/[sigma] corrections to the partonic hemisphere soft function, and hard matching for boosted tops at two loops. We find that the higher order corrections exhibit good convergence and reduced uncertainty in this cross section.

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Physics.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2017

Author dc:creator

• Bachu, Brad

Advisor dc:contributor.advisor

• lain W. Stewart.

• Physics.

Statement dc:rights

• MIT theses are protected by copyright. They may be viewed, downloaded, or printed from this source but further reproduction or distribution in any format is prohibited without written permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/111889

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/111889