GLAS-PPE/1999-16
November 1999

Precision Measurements of Particle
Masses using Jets at LEP2 J. Jason Ward
Department of Physics and Astronomy
University of Glasgow
Glasgow, G12 8QQ
United Kingdom
E-mail: Jason.Ward@cern.ch

Abstract:

How massive elementary particles get their mass is one of the greatest open questions in physics. Two of the major goals of the current LEP2 physics program that help to address this question are (a) to measure as precisely as possible the W Boson mass m_W and (b) to exclude or discover the Higgs Boson within the available kinematic region. The reconstruction of invariant masses with jets from 4-jet channels (e.g. WW $\rightarrow$ q$\bar{q}$q$\bar{q}$ and HZ $\rightarrow$ b$\bar{b}$q$\bar{q}$) and missing energy channels (e.g. WW $\rightarrow$ e$\bar{\nu}$q$\bar{q}$ and e⁺e^- $\rightarrow$ H$\nu$$\bar{\nu}$) is discussed. The emphasis is on the determination of m_W, from which the rôle of calorimetry in such a precision measurement is emphasised.

Invited Talk at the VIII International Conference on Calorimetry in
High Energy Physics, Lisbon, Portugal, June 13-19, 1999.