Light Gluino, Light Bottom Squark Scenario, and LEP Predictions
Abstract
Description
The scenario of light gluinos and light sbottoms was advocated to explain the discrepancy between the measured and theoretical production of $b$ quarks at the Tevatron. This scenario will have model-independent predictions for $Z\to q\bar q \tilde{g} \tilde{g}$ at the $Z^0$-pole, and $e^+ e^- \to q\bar q \tilde{g} \tilde{g}$ at LEPII. We show that the data for $Z\to q \bar q g^* \to q\bar q b \bar b$ at LEPI cannot constrain the scenario, because the ratio $Γ(Z \to q\bar q \tilde{g} \tilde{g})/ Γ(Z \to q \bar q g^* \to q\bar q b \bar b) = 0.15 - 0.04$ for $m_{\tilde{g}}= 12-16$ GeV is smaller than the uncertainty of the data. However, at LEPII the ratio $σ(e^+ e^- \to q\bar q \tilde{g} \tilde{g})/ σ(e^+ e^- \to q \bar q g^* \to q\bar q b \bar b) \simeq 0.4 - 0.2$ for $m_{\tilde{g}}= 12-16$ GeV, which may give an observable excess in $q\bar q b\bar b$ events; especially, the $4b$ events.
to match the published version in PRL
to match the published version in PRL