Showing papers by "Marcus Hohlmann published in 1999"

Inclusive jet cross section in p p collisions at s = 1.8 tev

Abstract: We report on the preliminary measurement of the inclusive jet cross section for {vert_bar}{eta}{vert_bar} {le} 0.5 at {radical}s = 1.8 TeV. Two data sets with integrated luminosities of 91 pb{sup {minus}1} and 14 pb{sup {minus}1} were collected at the Fermilab Tevatron {ovr p}p Collider with the D0 detector. The inclusive jet cross sections are measured and reported as a function of transverse jet energy (35 GeV {le} E{sub T} {le} 470 GeV) are in excellent agreement with next-to-leading order QCD. 11 refs., 4 figs.

Inclusive jet cross section in p̄p collisions at √ = 1.8 TeV

Abstract: We have made a precise measurement of the central inclusive jet cross section at sqrt(s) = 1.8 TeV. The measurement is based on an integrated luminosity of 92 pb-1 collected at the Fermilab Tevatron pbar-p Collider with the D-Zero detector. The cross section, reported as a function of jet transverse energy (ET >= 60 GeV) in the pseudorapidity interval |eta| <= 0.5, is in good agreement with predictions from next-to-leading order quantum chromodynamics.

Search for R-Parity violating supersymmetry using like-sign dielectrons in pp collisions at √ = 1.8 Tev

Abstract: We present a search for like-sign dielectron plus multijet events using $107{\mathrm{pb}}^{\ensuremath{-}1}$ of data in $p\overline{p}$ collisions at $\sqrt{s}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1.8\mathrm{TeV}$ collected in 1992--1995 by the CDF experiment. Finding no events that pass our selection, we set $\ensuremath{\sigma}\ifmmode\times\else\texttimes\fi{}\mathrm{BR}$ limits on two supersymmetric processes that can produce this experimental signature: gluino-gluino or squark-antisquark production with $R$-parity violating decays of the charm squark or lightest neutralino via a nonzero ${\ensuremath{\lambda}}_{121}^{\ensuremath{'}}$ coupling. We compare our results to the next-to-leading order calculations for gluino and squark production cross sections and set lower limits on $M(\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{g})$, $M({\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{t}}_{1})$, and $M(\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{q})$.

Measurement of Z0 and Drell-Yan production cross sections using dimuons in p̄p collisions at √s=1.8TeV

Abstract: We present a measurement of Z 0 boson and Drell-Yan production cross sections in pp collisions at √s =1.8TeV using a sample of 107 pb -1 accumulated by the Collider Detector at Fermilab. The Drell-Yan cross section is measured in the mass range of M μμ > 40GeV/c 2 . We compare the measurements with the predictions of quantum chromodynamics in both leading order and next-to-leading order, incorporating the recent parton distribution functions. The measurements are consistent with the standard model expectations. ©1999 The American Physical Society.

Search for New Particles Decaying to bb̄ in pp̄ Collisions at √s = 1.8 TeV

Abstract: We have used $87{\mathrm{pb}}^{\ensuremath{-}1}$ of data collected with the collider detector at Fermilab to search for new particles decaying to $b\overline{b}$. We present model-independent upper limits on the cross section for narrow resonances which exclude the color-octet technirho in the mass interval $350lMl440\mathrm{GeV}{/c}^{2}$. In addition, we exclude top-gluons, predicted in models of top-color-assisted technicolor, of width $\ensuremath{\Gamma}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0.3M$ in the mass range $280lMl670\mathrm{GeV}{/c}^{2}$, of width $\ensuremath{\Gamma}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0.5M$ in the mass range $340lMl640\mathrm{GeV}{/c}^{2}$, and of width $\ensuremath{\Gamma}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0.7M$ in the mass range $375lMl560\mathrm{GeV}{/c}^{2}$.