New Physics Effects from $e^+e^-\to f\bar f$ at a Linear Collider: the Role of $A_{LR, μ}$

Beccaria, Matteo; Renard, Fernand M.; Spagnolo, Stefania; Verzegnassi, Claudio

New Physics Effects from $e^+e^-\to f\bar f$ at a Linear Collider: the Role of $A_{LR, μ}$

Authors

Description

We discuss New Physics effects in fermion pair production at LC in the framework of the ``Z-peak subtracted approach'', a theoretical scheme that exploits the experimental measurements at LEP1 and SLC as input parameters. In particular, we discuss the role of the longitudinal polarization asymmetry $A_{LR,μ}$ which turns out to be a very sensitive probe to New Physics of universal type. The extension of the method to non universal effects is discussed and an application is given in two examples: general contact interactions and low energy gravity models with graviton exchange.
23 pages, REVTeX, 11 Encapsulated PostScript figures ECFA/DESY Workshop on Linear Collider, Obernai 16-19 October 1999