Please use this identifier to cite or link to this item: http://hdl.handle.net/2445/12467
Title: Study of top-quark polarization in single-top-quark production at the CERN LHC
Author: Espriu, D. (Domènec)
Manzano, J.
Keywords: Partícules (Física nuclear)
Interaccions febles (Física nuclear)
Particles (Nuclear physics)
Weak interactions (Nuclear physics)
Issue Date: 2002
Publisher: The American Physical Society
Abstract: This paper complements the study of single top production at the LHC aiming to estimate the sensitivity of different observables to the magnitude of the effective couplings. In a previous paper the dominant $W$-gluon fusion mechanism was considered, while here we extend the analysis to the subdominant (10% with our set of experimental cuts) s-channel process. In order to distinguish left from right effective couplings it is required to consider polarized cross-sections and/or include $m_b$ effects. The spin of the top is accessible only indirectly by measuring the angular distribution of its decay products. We show that the presence of effective right-handed couplings implies necessarily that the top is not in a pure spin state. We discuss to what extent quantum interference terms can be neglected in the measurement and therefore simply multiply production and decay probabilities clasically. The coarsening involved in the measurement process makes this possible. We determine for each process the optimal spin basis where theoretical errors are minimized and, finally, discuss the sensitivity in the s-channel to the effective right-handed coupling. The results presented here are all analytical and include $m_b$ corrections. They are derived within the narrow width approximation for the top.
Note: Reproducció digital del document publicat en format paper, proporcionada per PROLA i http://dx.doi.org/10.1103/PhysRevD.66.114009
It is part of: Physical Review D, 2002, vol. 66, núm. 11, 114009-1-114009-13
Related resource: http://doi.org/10.1103/PhysRevD.66.114009
URI: http://hdl.handle.net/2445/12467
ISSN: 0556-2821
Appears in Collections:Articles publicats en revistes (Física Quàntica i Astrofísica)

Files in This Item:
File Description SizeFormat 
509336.pdf374.31 kBAdobe PDFView/Open


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.