ar X iv : h ep - p h / 05 11 23 3 v 1 1 8 N ov 2 00 5 High Mass Particles Near Threshold

A consequence of the Higgs mechanism is that high mass particles, such as the Z 0-boson, the W ±-boson and the t-quark, are predicted to have masses that depend on the process by which they are produced. Thus, for example, particles produced singly are predicted to have higher masses than those produced in a pair near threshold. Quantitative details of this prediction are presented and discussed within the context of the current experimental situation. In the Standard Model of particle physics, the masses of the fundamental fermions and bosons are generated by the Higgs mechanism. Via this mechanism, the particle masses result from their interaction with an external scalar field known as the Higgs field. In a recent paper [1] it was pointed out that high mass particles can be used as detectors of the Higgs field. This possibility arises because high mass particles constitute significant sources of the Higgs field and the resulting source-modified field can be detected by other high mass particles that suffer induced mass shifts. In this paper explicit quantitative details are presented on the size of the effect in the cases of the Z mass in the ZZ threshold region, the W mass in the W W threshold region and the t mass in the tt threshold region [25]. An overview is also given of the current status of W , Z and t mass determinations in different production environments .