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Can MSSM with light sbottom and light gluino survive Z-peak constraints ?

Junjie Cao·Zhaohua Xiong·Jin Min Yang
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Abstract

In the framework of minimal supersymmetric model we examine the Z-peak constraints on the scenario of one light sbottom (2--5.5 GeV) and light gluino (12--16 GeV), which has been successfully used to explain the excess of bottom quark production in hadron collision. Such a scenario is found to be severely constrained by LEP Z-peak observables, especially by R_b, due to the large effect of gluino-sbottom loops. To account for the R_b data in this scenario, the other mass eigenstate of sbottom, i.e., the heavier one, must be lighter than 125 (195) GeV at 2-sigma (3-sigma) level, which should have been produced in association with the lighter one at LEP II and will probobaly be within the reach of Tevatron Run 2.

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Junjie Cao, Zhaohua Xiong, Jin Min Yang. 2002-03-04. Can MSSM with light sbottom and light gluino survive Z-peak constraints ?. https://doi.org/10.1103/physrevlett.88.111802

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