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

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

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

Matteo Beccaria·Fernand M. Renard·Stefania Spagnolo·Claudio Verzegnassi

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Abstract

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.

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Matteo Beccaria, Fernand M. Renard, Stefania Spagnolo, Claudio Verzegnassi. 1999-11-15. New Physics Effects from $e^+e^-\to f\bar f$ at a Linear Collider: the Role of $A_{LR, μ}$. https://arxiv.org/abs/hep-ph/9911359

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