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arXiv · hep-ph/0207235

Light Gluino and the Running of alpha_s

Cheng-Wei Chiang·Zumin Luo·Jonathan L. Rosner
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Abstract

A gluino in the mass range 12--16 GeV combined with a light (2--5.5 GeV) bottom squark, as has been proposed recently to explain an excess of b quark hadroproduction, would affect the momentum-scale dependence (``running'') of the strong coupling constant alpha_s in such a way as to raise its value at M_Z by about 0.014 +/- 0.001. If one combines sources of uncertainty at low (m_b) and high (M_Z) mass scales, one can only distinguish such an effect at slightly more than the 2 sigma level. Prospects for improvement in this situation, which include better lattice QCD simulations and better measurements at M_Z, are discussed.

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Cheng-Wei Chiang, Zumin Luo, Jonathan L. Rosner. 2002-12-03. Light Gluino and the Running of alpha_s. https://doi.org/10.1103/physrevd.67.035008

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