Using single top rapidity to measure V_td, V_ts, V_tb at hadron colliders

TL;DR

This paper proposes using single top rapidity distributions at hadron colliders to simultaneously constrain the CKM matrix elements V_td, V_ts, and V_tb, enhancing the precision of these measurements beyond traditional methods.

Contribution

It introduces a novel approach to measure V_td and V_ts directly from top rapidity distributions, improving the limits on these parameters at the LHC.

Findings

At LHC with 10 fb^-1, V_td limits can be halved.

Limits on V_tb can be reduced by 15%.

High statistics are needed at Tevatron for similar analysis.

Abstract

Single top production processes are usually regarded as the ones in which V_tb can be directly measured at hadron colliders. We show that the analysis of the single top rapidity distribution in t-channel and tW production can also set direct limits on V_td. At LHC with 10 fb^-1 at 14 TeV the combined limits on V_td may be reduced by almost a factor of two when the top rapidity distribution is used. This also implies that the limits on V_tb can also be reduced by 15%, since both parameters as well as V_ts must be simultaneously obtained from a global fit to data. At Tevatron the explotation of this distribution would require very high statistics.