1,884,608 research outputs found
Electroweak measurements from , and photon final states
We present the most recent precision electroweak measurements of single
and boson cross section and properties from the LHC and Tevatron colliders,
analyzing data collected by ATLAS, CDF, CMS, D0, and LHCb detectors. The
results include the measurement of the single and boson cross section
at LHC, the differential cross section measurements, the measurement of
boson mass, the measurement of and charge asymmetry. These measurements
provide precision tests on the electroweak theory, high order predictions and
the information can be used to constraint parton distribution functions.Comment: 14 pages, 16 figures, PIC201
Precision measurement and interpretation of inclusive W+, W- and Z/γ∗ production cross sections with the ATLAS detector
High-precision measurements by the ATLAS Collaboration are presented of inclusive W+→ℓ+ν, W-→ℓ-ν¯ and Z/γ∗→ℓℓ (ℓ=e,μ) Drell–Yan production cross sections at the LHC. The data were collected in proton–proton collisions at s=7TeV with an integrated luminosity of 4.6fb-1. Differential W+ and W- cross sections are measured in a lepton pseudorapidity range |ηℓ|<2.5. Differential Z/γ∗ cross sections are measured as a function of the absolute dilepton rapidity, for |yℓℓ|<3.6, for three intervals of dilepton mass, mℓℓ, extending from 46 to 150GeV. The integrated and differential electron- and muon-channel cross sections are combined and compared to theoretical predictions using recent sets of parton distribution functions. The data, together with the final inclusive e±p scattering cross-section data from H1 and ZEUS, are interpreted in a next-to-next-to-leading-order QCD analysis, and a new set of parton distribution functions, ATLAS-epWZ16, is obtained. The ratio of strange-to-light sea-quark densities in the proton is determined more accurately than in previous determinations based on collider data only, and is established to be close to unity in the sensitivity range of the data. A new measurement of the CKM matrix element |Vcs| is also provided
Inclusive jet cross section measurement at D0
We present a new preliminary measurement of the inclusive jet cross section
in pp-bar collisions based on a integrated luminosity of about 0.8 fb-1. The
data were acquired using the D0 detector between 2002 and 2005. Jets are
reconstructed using an iterative cone algorithm with radius R_cone = 0.7. The
inclusive jet cross section is presented as a function of transverse jet
momentum and rapidity. Predictions from perturbative QCD in next-to-leading
order, plus threshold corrections in 2-loop accuracy describe the shape in the
transverse jet momentum.Comment: 4 pages, 4 figures; proceedings of the DIS 2006 worksho
Measurement of inclusive charged current interactions on carbon in a few-GeV neutrino beam
The SciBooNE Collaboration reports a measurement of inclusive charged current
interactions of muon neutrinos on carbon with an average energy of 0.8 GeV
using the Fermilab Booster Neutrino Beam. We compare our measurement with two
neutrino interaction simulations: NEUT and NUANCE. The charged current
interaction rates (product of flux and cross section) are extracted by fitting
the muon kinematics, with a precision of 6-15% for the energy dependent and 3%
for the energy integrated analyses. We also extract CC inclusive interaction
cross sections from the observed rates, with a precision of 10-30% for the
energy dependent and 8% for the energy integrated analyses. This is the first
measurement of the CC inclusive cross section on carbon around 1 GeV. These
results can be used to convert previous SciBooNE cross section ratio
measurements to absolute cross section values.Comment: 21 pages, 16 figures. Accepted by Phys. Rev. D. Minor revisions to
match the accepted versio
The pp -> pp pi pi pi reaction channels in the threshold region
The cross section for prompt neutral and charged three pion production in pp
interactions was measured at excess energies in the range 160 - 217 MeV. That
comprises the first measurement of the pp->pp pi0pi0pi0 reaction and the
comparison with the pp->pp pi+pi-pi0 reaction, in a very direct way. The
experiment was performed above the eta meson production threshold and the cross
section normalization was obtained from a concurrent measurement of the
reaction pp->pp eta with the eta decaying into 3 pions. Since the same final
states are selected, the measurement has a low systematical error. The measured
cross section ratio sigma(pp->pp pi+pi-pi0)/sigma(pp->pp pi0\pi0\pi0) is
compared to predictions of dominance of different isobars in the intermediate
state.Comment: 12 pages, 4 figures New discussion on the pp->pp3pi reaction
mechanis
Measurement of Heavy Quark cross-sections at CDF
The measurement of heavy quark cross-sections provides important tests of the
QCD theory. This paper reviews recent measurements of single b-quark and
correlated b-quark cross-sections at CDF. Two new measurements of the single
b-quark production at CDF agree with the first result from CDF Run II. This
clarifies the experimental situation and confirms the recent agreement of
theoretical prediction with data. A new measurement of the correlated
cross-section with dimuon events at CDF is presented. It agrees with
theory and it does not confirm the anomalously large cross-section
seen in Run I by CDF and D in dimuon events.Comment: EPS HEP2007 conference held in Mancheste
Chargino Production at LEP2 in a Supergravity Model
In the framework of a particular supergravity model which provides a natural
solution to the --problem we show how the discovery of a chargino at LEP2
and the measurement of its mass and production cross--section, together with
the measurement of the mass of the lightest neutralino, would determine the
entire Higgs and SUSY spectrum. We give detailed predictions for the Higgs and
SUSY spectrum as a function of the chargino production cross--section, for
constant values of the lightest chargino and gluino masses.Comment: 11 pages, latex, 4 figures uufile
Longitudinal Analyses of the Effects of Trade Unions
This paper examines how measurement error biases longitudinal estimates of union effects. It develops numerical examples, statistical models, and econometric estimates which indicate that measurement error is a major problem in longitudinal data sets, so that longitudinal analyses do not provide the research panacea for determining the effects of unionism (or other economic forces) some have suggested. There are three major findings:1) The difference between the cross-section and longitudinal estimates is attributable in large part to random error in the measurement of who changes union status. Given modest errors of measurement, of the magnitudes observed,and a moderate proportion of workers changing union status, also of the magnitudes observed, measurement error biases downward estimated effects of unions by substantial amounts. 2) Longitudinal analysis of the effects of unionism on nonwage and wage outcomes tends to confirm the significant impact of unionism found in cross-section studies, with the longitudinal estimates of both nonwage and wage outcomes lover in the longitudinal analysis than in the cross-section analysis of the same data set. 3) The likely upward bias of cross-section estimates of the effect of unions and the likely downward bias of longitudinal estimates suggests that,under reasonable conditions, the two sets of estimates bound the "true" union impact posited in standard models of what unions do.
Measurement of the cross section for the production of a W boson in association with b-jets in pp collisions at √s = 7 TeV with the ATLAS detector
A measurement is presented of the cross section for the production of a W boson with one or two jets, of which at least one must be a b-jet, in pp collisions at √s = 7 TeV. Production via top decay is not included in the signal definition. The measurement is based on 35 pb^(-1) of data collected with the ATLAS detector at the LHC. The W +b-jet cross section is defined for jets reconstructed with the anti-k_t clustering algorithm with transverse momentum above 25 GeV and rapidity within ±2.1. The b-jets are identified by reconstructing secondary vertices. The fiducial cross section is measured both for the electron and muon decay channel of the W boson and is found to be 10.2 ± 1.9(stat) ± 2.6(syst) pb for one lepton flavour. The results are compared with next-to-leading order QCD calculations, which predict a cross section smaller than, though consistent with, the measured value
Measurement of the neutron capture cross-section of 236U
Proposal: Measurement of the neutron capture cross-section of 236UPreprin
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