2010/10/31 by Edmond L. Berger, Marco Guzzi, Hung-Liang Lai +4
Mathematics · Physics and Astronomy · #Distribution (mathematics) #Fermion #High-Energy Particle Collisions Research #Mathematical analysis #Mathematics #Octet #Particle physics #Particle physics theoretical and experimental studies #Parton #Physics #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Quark #hep-ph
paper · pdf · doi:10.1103/physrevd.82.114023
published as Phys.Rev.D82:114023,2010 · 36 pages, 14 figures. Accepted for a publication on Phys. Rev. D (2010)
arxiv created 2010/11/10 · openalex publication_date 2010/12/22 · arxiv updated 2011/01/20 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We report a parton distribution function analysis of a complete set of hadron scattering data, in which a color-octet fermion (such as a gluino of supersymmetry) is incorporated as an extra parton constituent along with the usual standard model constituents. The data set includes the most up-to-date results from deep inelastic scattering and from jet production in hadron collisions. Another feature is the inclusion in the fit of data from determinations of the strong coupling \ensuremathαs(Q) at large and small values of the hard scale Q. Our motivation is to determine the extent to which the global parton distribution function analysis may provide constraints on the new fermion, as a function of its mass and \ensuremathαs(MZ), independent of assumptions such as the mechanism of gluino decays. Based on this analysis, we find that gluino masses as low as 30 to 50 GeV may be compatible with the current hadronic data. Gluino masses below 15 GeV (25 GeV) are excluded if \ensuremathαs(MZ) varies freely (is equal to 0.118). At the outset, stronger constraints had been anticipated from jet production cross sections, but experimental systematic uncertainties, particularly in normalization, reduce the discriminating power of these data.