1,689 research outputs found

### Tests of QCD in W and Z Production at Tevatron

We present measurements of the production cross sections times leptonic
branching fractions and the transverse momentum distributions of $W$ and $Z$
bosons in $p\bar{p}$ collisions at $\sqrt{s}=1.8$ TeV using data collected with
the D{\O}detector at the Fermilab Tevatron $p\bar{p}$ collider. A preliminary
measurement of the $W$ charge asymmetry is also presented.Comment: 25 pages in a uucoded PS fil

Recommended from our members

### Search for anomalous WW and WZ production at D0

We present a preliminary result from a search for anomalous WW and WZ production in p\bar{p} collisions at \sqrt{s}=1.8 TeV using p\bar{p}\rightarrow e\nu jj events observed during the 1992--1993 run of the Fermilab Tevatron collider. A fit to the p_T spectrum of W(e\nu) yields direct limits on the CP--conserving anomalous WW\gamma and WWZ coupling parameters of -0.89<\Delta\kappa<1.07~~(\lambda=0) and -0.66<\lambda<0.67~~(\Delta\kappa=0) at the 95\ \% confidence level, assuming that the WWZ coupling parameters are equal to the WW\gamma coupling parameters, and a form factor scale \Lambda=1.5~TeV

### Tests of QCD in W and Z production at Tevatron

We present measurements of the production cross sections times leptonic branching fractions and the transverse momentum distributions of W and Z bosons in p\bar{p} collisions at \sqrt{s}=1.8~TeV using data collected with the D\O\ detector at the Fermilab Tevatron p\bar{p} collider. A preliminary measurement of the W charge asymmetry is also presented

### Warped Phenomenology

We explore the phenomenology associated with the recently proposed localized
gravity model of Randall and Sundrum where gravity propagates in a
5-dimensional non-factorizable geometry and generates the 4-dimensional
weak-Planck scale hierarchy by an exponential function of the compactification
radius, called a warp factor. The Kaluza-Klein tower of gravitons which emerge
in this scenario have strikingly different properties than in the factorizable
case with large extra dimensions. We derive the form of the graviton tower
interactions with the Standard Model fields and examine their direct production
in Drell-Yan and dijet events at the Tevatron and LHC as well as the KK
spectrum line-shape at high-energy linear \epem colliders. In the case where
the first KK excitation is observed, we outline the procedure to uniquely
determine the parameters of this scenario. We also investigate the effect of KK
tower exchanges in contact interaction searches. We find that present
experiments can place meaningful constraints on the parameters of this model.Comment: 14 pages, LaTex, 3 fig

### Window on Higgs Boson: Fourth Generation $b^\prime$ Decays Revisited

Direct and indirect searches of the Higgs boson suggest that 113 GeV
$\lesssim m_H \lesssim$ 170 GeV is likely. With the LEP era over and the
Tevatron Run II search via $p\bar p \to WH+X$ arduous, we revisit a case where
$WH$ or $ZH +$ jets could arise via strong $b^\prime\bar b^\prime$ pair
production. In contrast to 10 years ago, the tight electroweak constraint on
$t^\prime$--$b^\prime$ (hence $t^\prime$--$t$) splitting reduces FCNC
$b^\prime\to bZ$, $bH$ rates, making $b^\prime\to cW$ naturally competitive.
Such a "cocktail solution" is precisely the mix that could evade the CDF search
for $b^\prime\to bZ$, and the $b^\prime$ may well be lurking below the top. In
light of the Higgs program, this two-in-one strategy should be pursued.Comment: 4 pages, RevTex, 4 eps figures, One more figure, version to be
published in Phys. Rev.

### Spectrophotometric determination of Phenylephrine hydrochloride and Salbutamol sulphate drugs in pharmaceutical preparations using diazotized Metoclopramide hydrochloride

A spectrophotometric method has been proposed for the determination of two drugs containing phenol group [phenylephrine hydrochloride (PHP) and salbutamol sulphate (SLB)] in pharmaceutical dosage forms. The method is based on the diazotization reaction of metoclopramide hydrochloride (MCP) and coupling of the diazotized reagent with drugs in alkaline medium to give intense orange colored product (?max at 470 nm for each of PHP and SLB). Variable parameters such as temperature, reaction time and concentration of the reactants have been analyzed and optimized. Under the proposed optimum condition, Beer’s law was obeyed in the concentration range of 1-32 and 1-14 ?g mL-1 for PHP and SLB, respectively. The limit of detection (LOD) and limit of quantification (LOQ) for each of PHP and SLB were 0.60, 0.52 ?g mL-1 and 2.02, 1.72 ?g mL-1, respectively. No interference was observed from common excipients present in pharmaceutical preparations. The good correlation coefficients and low relative standard deviation assert the applicability of this method. The suggested method was further applied for the determinations of drugs in commercial pharmaceutical preparations, which was compared statistically with reference methods by means of t- test and F- test and were found not to differ significantly at 95% confidence level. The procedure was characterized by its simplicity with accuracy and precision

### $ZZ\gamma$ and $Z\gamma\gamma$ couplings in $\gamma e$ collision with polarized beams

The potential of $\gamma$e mode of linear $e^{+}e^{-}$ collider to probe
$ZZ\gamma$ and $Z\gamma\gamma$ vertices is investigated through the Z boson
production from the procees $\gamma e\to Z e$. Considering the longitudinal and
transverse polarization states of the Z boson and incoming polarized beams we
find the 95% C.L. limits on the form factors $h_{3}^{Z}$, $h_{4}^{Z}$,
$h_{3}^{\gamma}$ and $h_{4}^{\gamma}$ with integrated luminosity 500$fb^{-1}$
and $\sqrt{s}=$0.5, 1, 1.5 TeV energies. It is shown that the polarization can
improve sensitivities by factors 2-3 depending on the energy.Comment: 12 pages, 8 EPS figure

Recommended from our members

### Search for light top squarks with the D{O} detector

We present preliminary results of a search for pair produced top squarks, the supersymmetric partners to the top quark, under the assumption that the two-body decay {bar t}{sub 1} {yields} b{bar W}{sub 1} and three-body decay {bar t}{sub 1} {yields} bW{bar Z}{sub 1} are kinematically forbidden. This scenario is realized if {bar t}{sub 1} is considerably lighter than all other squarks as well as {bar W}{sub 1}, all {bar v}s, and the top quark. Such light top squarks will dominantly decay via {bar t}{sub 1} {yields} c{bar Z}{sub 1} yielding a signal of two acollinear jets with (E){sub T}. The data reported here were taken during the 1992-1993 run of the D0 detector at the Fermilab Tevatron p{bar p} collider operating at {radical}s = 1.8 TeV

Recommended from our members

### The dijet mass spectrum and angular distributions with the D0 detector

We present preliminary results from an analysis of dijet data collected during the 1994-95 Tevatron Collider run with an integrated luminosity of 91 pb{sup -1}. Measurements of dijet mass spectra and dijet angular distributions in {anti p}p collisions at {radical}s- = 1.8 TeV are compared with next-to-leading order QCD theory

- …