ar X iv : h ep - p h / 97 07 21 4 v 1 2 J ul 1 99 7 UCRHEP - T 188 July 1997 S , T , and Leptoquarks at HERA
نویسنده
چکیده
If the recently discovered anomalous events at HERA are due to a scalar leptoquark, then it is very likely to have weak isospin I = 1/2. In that case, present precision measurements of the oblique radiative parameters S and T provide strong constraints on the mass of the other component of this doublet. If the standard model is extended to include such a doublet, a slightly better fit may in fact be obtained. However, in specific proposed models where this doublet comes from a larger symmetry, there are often additional large and positive contributions to S from exotic heavy fermions which far exceed the present experimental limit. A way to improve the Tevatron exploration of leptoquarks is proposed.
منابع مشابه
ar X iv : h ep - p h / 97 09 23 5 v 1 3 S ep 1 99 7 SLAC - PUB - 7643 September 1997
Attempts to understand the recent observation of an excess of events in the neutral and charged current channels at high−Q2 at HERA has provided an excellent example of how experiments at both low and high energies can be used to simultaneously constrain scenarios which predict new physics beyond the Standard Model. In this talk I will discuss this subject from the point of view of the construc...
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