31 research outputs found
Measurement of the ttbar Production Cross Section in ppbar collisions at sqrt s = 1.96 TeV in the All Hadronic Decay Mode
We report a measurement of the ttbar production cross section using the
CDF-II detector at the Fermilab Tevatron. The analysis is performed using 311
pb-1 of ppbar collisions at sqrt(s)=1.96 TeV. The data consist of events
selected with six or more hadronic jets with additional kinematic requirements.
At least one of these jets must be identified as a b-quark jet by the
reconstruction of a secondary vertex. The cross section is measured to be
sigma(tbart)=7.5+-2.1(stat.)+3.3-2.2(syst.)+0.5-0.4(lumi.) pb, which is
consistent with the standard model prediction.Comment: By CDF collaboratio
Search for chargino-neutralino production in ppbar collisions at sqrt(s) = 1.96 TeV
We present the results of a search for associated production of the chargino
and neutralino supersymmetric particles using up to 1.1 fb-1 of integrated
luminosity collected by the CDF II experiment at the Tevatron ppbar collider at
a center-of-mass energy of 1.96 TeV. The search is conducted by analyzing
events with a large transverse momentum imbalance and either three charged
leptons or two charged leptons of the same electric charge. The numbers of
observed events are found to be consistent with standard model expectations.
Upper limits on the production cross section are derived in different
theoretical models. In one of these models a lower limit on the mass of the
chargino is set at 129 GeV/c^2 at the 95% confidence level.Comment: To be submitted to Phys.Rev.Let
Soybean Leaves Contain Multiple Lipoxygenases
Chromatofocusing of soybean (Glycine max L.) leaf lipoxygenases
revealed three distinct peaks of activity. Based on their
isoelectric points (pis), pH optima, and mutant analysis it appears
that the leaf isozymes are different from those described from
mature soybean seed. At least one leaf lipoxygenase appears to
differ from those found in hypocotyls. The pis of the main bands
of the three leaf lipoxygenase peaks are 6.67, 5.91, and 5.67. The
pH optima curves of three active fractions exhibit peaks at pH
6.2, 5.5, and 8.5, respectively. One of the fractions has two
polypeptides with slightly different molecular weights, both of
which react to soybean seed lipoxygenase antibodies. The other
two fractions contain a polypeptide of unit molecular weight
reacting with the lipoxygenase antibodies