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A review of the status of searches for Supersymmetry at the Tevatron Collider as of the Summer of 1997. This is a new version of the previous review, substantially shortened to fit editorial guidelines, and significantly different to warrant a separate posting. To appear in Perspectives on Supersymmetry, ed. G.L. Kane (World Scientific, Singapore).
We review the status of searches for Supersymmetry at the Tevatron Collider. After discussing the theoretical aspects relevant to the production and decay of supersymmetric particles at the Tevatron, we present the current results for Runs Ia and Ib as of the summer of 1997. To appear in the book Perspectives in Supersymmetry, edited by G.L. Kane, World Scientific.
These lectures contain an introduction to the search for supersymmetry at hadron colliders. The Tevatron is one of high-energy physics most sophisticated tools. The high center-of-mass energy of its proton-antiproton collisions makes it an ideal place to search for physics beyond the Standard Model, such as supersymmetry. Two experiments, CDF and DO, completed a long data taking period in summer of 1995, yielding over $100 p b^{-1}$ of proton-- antiproton interactions. The data recorded by the experiments are still being analysed. The lectures outline the strategies in the search for supersymmetry at the Tevatron and examine the major analyses in detail. Results obtained by the two experiments are included where available.
A search for stop production in R-parity-violating supersymmetry has been performed in $e^{+}p$ interactions with the ZEUS detector at HERA, using an integrated luminosity of 65 pb$^{-1}$. At HERA, the R-parity-violating coupling $lambda$ allows resonant squark production, $e^+dtotilde{q}$. Since the lowest-mass squark state in most supersymmetry models is the light stop, $tilde{t}$, this search concentrated on production of $tilde{t}$, followed either by a direct R-parity-violating decay, or by the gauge decay to $btilde{chi}^+_{1}$. No evidence for stop production was found and limits were set on $lambda_{131}$ as a function of the stop mass in the framework of the Minimal Supersymmetric Standard Model. The results have also been interpreted in terms of constraints on the parameters of the minimal Supergravity model.
We study the production and decays of top squarks (stops) at the Tevatron collider in models of low-energy supersymmetry breaking. We consider the case where the lightest Standard Model (SM) superpartner is a light neutralino that predominantly decays into a photon and a light gravitino. Considering the lighter stop to be the next-to-lightest Standard Model superpartner, we analyze stop signatures associated with jets, photons and missing energy, which lead to signals naturally larger than the associated SM backgrounds. We consider both 2-body and 3-body decays of the top squarks and show that the reach of the Tevatron can be significantly larger than that expected within either the standard supergravity models or models of low-energy supersymmetry breaking in which the stop is the lightest SM superpartner. For a modest projection of the final Tevatron luminosity, L = 4 fb-1, stop masses of order 300 GeV are accessible at the Tevatron collider in both 2-body and 3-body decay modes. We also consider the production and decay of ten degenerate squarks that are the supersymmetric partners of the five light quarks. In this case we find that common squark masses up to 360 GeV are easily accessible at the Tevatron collider, and that the reach increases further if the gluino is light.
The discovery of a light Higgs boson at the LHC opens a broad program of studies and measurements to understand the role of this particle in connection with New Physics and Cosmology. Supersymmetry is the best motivated and most thoroughly formulated and investigated model of New Physics which predicts a light Higgs boson and can explain dark matter. This paper discusses how the study of the Higgs boson connects with the search for supersymmetry and for dark matter at the LHC and at a future $e^+e^-$ collider and with dedicated underground dark matter experiments.