1,148 research outputs found
PSY46 PSYCHOMETRIC ANALYSIS OFTHE THREE-FACTOR EATING QUESTIONNAIRE: RESULTS FROM A LARGE DIVERSE SAMPLE OF OBESE AND NON-OBESE SUBJECTS
The running coupling of 8 flavors and 3 colors
We compute the renormalized running coupling of SU(3) gauge theory coupled to
N_f = 8 flavors of massless fundamental Dirac fermions. The recently proposed
finite volume gradient flow scheme is used. The calculations are performed at
several lattice spacings allowing for a controlled continuum extrapolation. The
results for the discrete beta-function show that it is monotonic without any
sign of a fixed point in the range of couplings we cover. As a cross check the
continuum results are compared with the well-known perturbative continuum
beta-function for small values of the renormalized coupling and perfect
agreement is found.Comment: 15 pages, 17 figures, published versio
Lattice QCD at the physical point: Simulation and analysis details
We give details of our precise determination of the light quark masses
m_{ud}=(m_u+m_d)/2 and m_s in 2+1 flavor QCD, with simulated pion masses down
to 120 MeV, at five lattice spacings, and in large volumes. The details concern
the action and algorithm employed, the HMC force with HEX smeared clover
fermions, the choice of the scale setting procedure and of the input masses.
After an overview of the simulation parameters, extensive checks of algorithmic
stability, autocorrelation and (practical) ergodicity are reported. To
corroborate the good scaling properties of our action, explicit tests of the
scaling of hadron masses in N_f=3 QCD are carried out. Details of how we
control finite volume effects through dedicated finite volume scaling runs are
reported. To check consistency with SU(2) Chiral Perturbation Theory the
behavior of M_\pi^2/m_{ud} and F_\pi as a function of m_{ud} is investigated.
Details of how we use the RI/MOM procedure with a separate continuum limit of
the running of the scalar density R_S(\mu,\mu') are given. This procedure is
shown to reproduce the known value of r_0m_s in quenched QCD. Input from
dispersion theory is used to split our value of m_{ud} into separate values of
m_u and m_d. Finally, our procedure to quantify both systematic and statistical
uncertainties is discussed.Comment: 45 page
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Towards a typology for constrained climate model forecasts
In recent years several methodologies have been developed to combine and interpret ensembles of climate models with the aim of quantifying uncertainties in climate projections. Constrained climate model forecasts have been generated by combining various choices of metrics used to weight individual ensemble members, with diverse approaches to sampling the ensemble. The forecasts obtained are often significantly different, even when based on the same model output. Therefore, a climate model forecast classification system can serve two roles: to provide a way for forecast producers to self-classify their forecasts; and to provide information on the methodological assumptions underlying the forecast generation and its uncertainty when forecasts are used for impacts studies. In this review we propose a possible classification system based on choices of metrics and sampling strategies. We illustrate the impact of some of the possible choices in the uncertainty quantification of large scale projections of temperature and precipitation changes, and briefly discuss possible connections between climate forecast uncertainty quantification and decision making approaches in the climate change context
Forward-Backward Asymmetry in Top Quark Production in ppbar Collisions at sqrt{s}=1.96 TeV
Reconstructable final state kinematics and charge assignment in the reaction
ppbar->ttbar allows tests of discrete strong interaction symmetries at high
energy. We define frame dependent forward-backward asymmetries for the outgoing
top quark in both the ppbar and ttbar rest frames, correct for experimental
distortions, and derive values at the parton-level. Using 1.9/fb of ppbar
collisions at sqrt{s}=1.96 TeV recorded with the CDF II detector at the
Fermilab Tevatron, we measure forward-backward top quark production asymmetries
in the ppbar and ttbar rest frames of A_{FB,pp} = 0.17 +- 0.08 and A_{FB,tt} =
0.24 +- 0.14.Comment: 7 pages, 2 figures, submitted to Phys.Rev.Lett, corrected references
and change of tex
Studying the Underlying Event in Drell-Yan and High Transverse Momentum Jet Production at the Tevatron
We study the underlying event in proton-antiproton collisions by examining
the behavior of charged particles (transverse momentum pT > 0.5 GeV/c,
pseudorapidity |\eta| < 1) produced in association with large transverse
momentum jets (~2.2 fb-1) or with Drell-Yan lepton-pairs (~2.7 fb-1) in the
Z-boson mass region (70 < M(pair) < 110 GeV/c2) as measured by CDF at 1.96 TeV
center-of-mass energy. We use the direction of the lepton-pair (in Drell-Yan
production) or the leading jet (in high-pT jet production) in each event to
define three regions of \eta-\phi space; toward, away, and transverse, where
\phi is the azimuthal scattering angle. For Drell-Yan production (excluding the
leptons) both the toward and transverse regions are very sensitive to the
underlying event. In high-pT jet production the transverse region is very
sensitive to the underlying event and is separated into a MAX and MIN
transverse region, which helps separate the hard component (initial and
final-state radiation) from the beam-beam remnant and multiple parton
interaction components of the scattering. The data are corrected to the
particle level to remove detector effects and are then compared with several
QCD Monte-Carlo models. The goal of this analysis is to provide data that can
be used to test and improve the QCD Monte-Carlo models of the underlying event
that are used to simulate hadron-hadron collisions.Comment: Submitted to Phys.Rev.
Precision measurement of the top quark mass from dilepton events at CDF II
We report a measurement of the top quark mass, M_t, in the dilepton decay
channel of
using an integrated luminosity of 1.0 fb^{-1} of p\bar{p} collisions collected
with the CDF II detector. We apply a method that convolutes a leading-order
matrix element with detector resolution functions to form event-by-event
likelihoods; we have enhanced the leading-order description to describe the
effects of initial-state radiation. The joint likelihood is the product of the
likelihoods from 78 candidate events in this sample, which yields a measurement
of M_{t} = 164.5 \pm 3.9(\textrm{stat.}) \pm 3.9(\textrm{syst.})
\mathrm{GeV}/c^2, the most precise measurement of M_t in the dilepton channel.Comment: 7 pages, 2 figures, version includes changes made prior to
publication by journa
Measurement of the Ratios of Branching Fractions B(Bs -> Ds pi pi pi) / B(Bd -> Dd pi pi pi) and B(Bs -> Ds pi) / B(Bd -> Dd pi)
Using 355 pb^-1 of data collected by the CDF II detector in \ppbar collisions
at sqrt{s} = 1.96 TeV at the Fermilab Tevatron, we study the fully
reconstructed hadronic decays B -> D pi and B -> D pi pi pi. We present the
first measurement of the ratio of branching fractions B(Bs -> Ds pi pi pi) /
B(Bd -> Dd pi pi pi) = 1.05 pm 0.10 (stat) pm 0.22 (syst). We also update our
measurement of B(Bs -> Ds pi) / B(Bd -> Dd pi) to 1.13 pm 0.08 (stat) pm 0.23
(syst) improving the statistical uncertainty by more than a factor of two. We
find B(Bs -> Ds pi) = [3.8 pm 0.3 (stat) pm 1.3 (syst)] \times 10^{-3} and B(Bs
-> Ds pi pi pi) = [8.4 pm 0.8 (stat) pm 3.2 (syst)] \times 10^{-3}.Comment: 7 pages, 2 figure
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