NLO and off-shell effects in top quark mass determinations

• Main Authors: Gudrun Heinrich, Andreas Maier, Richard Nisius, Johannes Schlenk, Markus Schulze, Ludovic Scyboz, Jan Winter
• Format: Article
• Language: English
• Published: SpringerOpen 2018-07-01
• Series: Journal of High Energy Physics
• Subjects: QCD Phenomenology; NLO Computations
• Online Access: http://link.springer.com/article/10.1007/JHEP07(2018)129

Abstract We study the impact of different theoretical descriptions of top quark pair production on top quark mass measurements in the di-lepton channel. To this aim, the full NLO corrections to pp→W+W−bb¯→e+νeμ−ν¯μbb¯ $$ pp\to {W}^{+}{W}^{-}b\overline{b}\to \left({e}^{+}{\nu}_e\right)\left({\mu}^{-}{\overline{\nu}}_{\mu}\right)b\overline{b} $$ production are compared to calculations in the narrow width approximation, where the production of a top quark pair is calculated at NLO and combined with three different descriptions of the top quark decay: leading order, next-to-leading order and via a parton shower. The different theory predictions then enter the calibration of template fit functions, which are used for a fit to pseudo-data. The offsets in the top quark mass resulting from the fits based on the various theoretical descriptions are determined.