32 research outputs found
Measurement of the Boson Mass
A measurement of the mass of the boson is presented based on a sample of
5982 decays observed in collisions at
= 1.8~TeV with the D\O\ detector during the 1992--1993 run. From a
fit to the transverse mass spectrum, combined with measurements of the
boson mass, the boson mass is measured to be .Comment: 12 pages, LaTex, style Revtex, including 3 postscript figures
(submitted to PRL
Second Generation Leptoquark Search in p\bar{p} Collisions at = 1.8 TeV
We report on a search for second generation leptoquarks with the D\O\
detector at the Fermilab Tevatron collider at = 1.8 TeV.
This search is based on 12.7 pb of data. Second generation leptoquarks
are assumed to be produced in pairs and to decay into a muon and quark with
branching ratio or to neutrino and quark with branching ratio
. We obtain cross section times branching ratio limits as a function
of leptoquark mass and set a lower limit on the leptoquark mass of 111
GeV/c for and 89 GeV/c for at the 95%\
confidence level.Comment: 18 pages, FERMILAB-PUB-95/185-
Search for Production via Trilepton Final States in collisions at TeV
We have searched for associated production of the lightest chargino,
, and next-to-lightest neutralino, , of the
Minimal Supersymmetric Standard Model in collisions at
\mbox{ = 1.8 TeV} using the \D0 detector at the Fermilab Tevatron
collider. Data corresponding to an integrated luminosity of 12.5 \ipb
were examined for events containing three isolated leptons. No evidence for
pair production was found. Limits on
BrBr are
presented.Comment: 17 pages (13 + 1 page table + 3 pages figures). 3 PostScript figures
will follow in a UUEncoded, gzip'd, tar file. Text in LaTex format. Submitted
to Physical Review Letters. Replace comments - Had to resumbmit version with
EPSF directive
The Azimuthal Decorrelation of Jets Widely Separated in Rapidity
This study reports the first measurement of the azimuthal decorrelation
between jets with pseudorapidity separation up to five units. The data were
accumulated using the D{\O}detector during the 1992--1993 collider run of the
Fermilab Tevatron at 1.8 TeV. These results are compared to
next--to--leading order (NLO) QCD predictions and to two leading--log
approximations (LLA) where the leading--log terms are resummed to all orders in
. The final state jets as predicted by NLO QCD
show less azimuthal decorrelation than the data. The parton showering LLA Monte
Carlo {\small HERWIG} describes the data well; an analytical LLA prediction
based on BFKL resummation shows more decorrelation than the data.Comment: 6 pages with 4 figures, all uuencoded and gzippe
Jet Production via Strongly-Interacting Color-Singlet Exchange in Collisions
A study of the particle multiplicity between jets with large rapidity
separation has been performed using the D{\O}detector at the Fermilab Tevatron
Collider operating at TeV. A significant excess of
low-multiplicity events is observed above the expectation for color-exchange
processes. The measured fractional excess is , which is consistent with a strongly-interacting
color-singlet (colorless) exchange process and cannot be explained by
electroweak exchange alone. A lower limit of 0.80% (95% C.L.) is obtained on
the fraction of dijet events with color-singlet exchange, independent of the
rapidity gap survival probability.Comment: 15 pages (REVTeX), 3 PS figs (uuencoded/tar compressed, epsf.sty)
Complete postscript available at http://d0sgi0.fnal.gov/d0pubs/journals.html
Submitted to Physical Review Letter
Measurement of the and Couplings in Collisions at TeV
We have directly measured the ZZ-gamma and Z-gamma-gamma couplings by
studying p pbar --> l+ l- gamma + X, (l = e, mu) events at the CM energy of
1.813.3 pb^-1)
for the electron (muon) channel, yields the following 95% confidence level
limits on the anomalous CP-conserving ZZ-gamma couplings: -1.9 < h^Z_30 < 1.8
(h^Z_40 = 0), and -0.5 < h^Z_40 < 0.5 (h^Z_30 = 0), for a form-factor scale
Lambda = 500 GeV. Limits for the Z-gamma-gamma$ couplings and CP-violating
couplings are also discussed.Comment: 11 pages, 1 table, and 3 figure
Measurement of the gauge boson couplings in Collisions at TeV
The gauge boson couplings were measured using () events at TeV observed with the
{D\O} detector at the Fermilab Tevatron Collider. The signal, obtained from the
data corresponding to an integrated luminosity of , agrees
well with the Standard Model prediction. A fit to the photon transverse energy
spectrum yields limits at the 95% confidence level on the CP--conserving
anomalous coupling parameters of ( = 0) and
( = 0).Comment: 16pages (14pages + 2figure pages) Uses ReVTEX Two postscript files
for figures will follow immediatel
W and Z Boson Production in PbarP Collisions at Sqrt(s)=1.8 TeV
The inclusive cross sections times leptonic branching ratios for W and Z
boson production in PbarP collisions at Sqrt(s)=1.8 TeV were measured using the
D0 detector at the Fermilab Tevatron collider:
Sigma_W*B(W->e, nu) = 2.36 +/- 0.07 +/- 0.13 nb,
Sigma_W*B(W->mu,nu) = 2.09 +/- 0.23 +/- 0.11 nb,
Sigma_Z*B(Z-> e, e) = 0.218 +/- 0.011 +/- 0.012 nb,
Sigma_Z*B(Z->mu,mu) = 0.178 +/- 0.030 +/- 0.009 nb.
The first error is the combined statistical and systematic uncertainty, and
the second reflects the uncertainty in the luminosity. For the combined
electron and muon analyses we find:
[Sigma_W*B(W->l,nu)]/[Sigma_Z*B(Z->l,l)] = 10.90 +/- 0.49.
Assuming Standard Model couplings, this result is used to determine the width
of the W boson:
Gamma(W) = 2.044 +/- 0.093 GeV.Comment: 11 pages (including 2 figure pages), in REVTEX. Two PostScript
figures are appended in a UUencoded fil
Determination of the Mass of the W Boson Using the D0 Detector at the Tevatron
A measurement of the mass of the W boson is presented which is based on a
sample of 5982 W -> e nu decays observed in pbar-p collisions at sqrt(s) = 1.8
TeV with the D0 detector during the 1992-1993 run. From a fit to the transverse
mass spectrum, combined with measurements of the Z boson mass, the W boson mass
is measured to be M_W = 80.350+-0.140(stat)+-0.165(sys)+-0.160(scale) GeV/c^2.
Detailed discussions of the determination of the absolute energy scale, the
measured efficiencies, and all systematic uncertainties are presented.Comment: 152 pages, 51 figures in 76 files 2 latex file