Oct 2018 - Sep 2019

All-order corrections for top-mass determinations in the large number of flavours

by Silvia Ferrario Ravasio (IPPP)


Despite the increasing precision of top-mass measurements at the LHC, their theoretical interpretation is still a matter of discussion since linear renormalons affect the top pole-mass definition.  Using the large number of flavour approximation, we compute the process of single-top production and decay at all orders. We devise a simple method that can be used to investigate the presence of linear renormalons for a generic infrared observable, either expressed in terms of the pole mass or in terms of the $\overline{\rm MS}$ mass.  We show as examples the total cross section, the energy of the $W$ boson and the reconstructed-top mass, highlighting the role of renormalons coming from jet-tagging and those coming from the pole-mass definition.