6,367 research outputs found
Dijet Cross Section and Longitudinal Double Spin Asymmetry Measurements in Polarized Proton-proton Collisions at \sqrt{s}=200 GeV at STAR
These proceedings show the preliminary results of the dijet cross sections
and the dijet longitudinal double spin asymmetries A_LL in polarized
proton-proton collisions at \sqrt{s} = 200 GeV at the mid-rapidity |eta| < 0.8.
The integrated luminosity of 5.39 pb^{-1} collected during RHIC Run-6 was used
in the measurements. The preliminary results are presented as functions of the
dijet invariant mass M_jj. The dijet cross sections are in agreement with
next-to-leading-order pQCD predictions. The A_LL is compared with theoretical
predictions based on various parameterizations of polarized parton
distributions of the proton. Projected precision of data analyzed to date from
Run-9 are shown.Comment: 8 pages, 5 figures, Proceedings of the SPIN2010 conference (Juelich,
Germany, 2010
MUSCLE ARCHITECTURE AND THE RATIO OF JOINT TORQUE TO MUSCLE VOLUME OF TRICEPS SURAE MUSCLES IN YOUNG MEN AND WOMEN
INTRODUCTION: Muscle volume is a major determinant of joint torque (Fukunaga et al., 2001). However, it is not clear whether there are gender-differences in a relationship between joint torque and muscle volume. It is not clear also about muscle architecture, e.g., physiological cross-sectional area (PCSA) and fascicle length. We aim to compare 1) muscle architecture under the maximal voluntary contraction condition and muscle volume (MVTS) of the triceps surae muscles (TS), and 2) the relationship between MVC and MVTS, for young men and women
FORCE-LENGTH RELATIONSHIPS OF HUMAN GASTROCNEMIUS AND SOLEUS MUSCLES IN VIVO
INTRODUCTION: Synergistic muscle have different architecture, and therefore could have different force-length relationships for the same joint angle changes. Previous studies have failed to reveal the force-length relationships of synergistic muscles. The purpose of this study was to investigate the force-length relationships of the triceps surae muscles for humans in vivo
CHANGES IN FORCE-LENGTH RELATIONSHIP OF TRICEPS SURAE MUSCLES AFTER REPEATED ECCENTRIC-CONCENTRIC EXERCISES
INTRODUCTION: Postexercise muscle soreness develops gradually 24 to 48 hours after an eccentric exercise. The prolonged reduction of maximal voluntary force also occurs after eccentric exercise (Nosaka et al, 1991). The reduction in maximal force is thought to be due to peripheral muscle damage derived by eccentric lengthening, but the exact mechanisms are yet to be discovered. One possibility of the reduction in force is the shifting of the optimal length for force production (Prasartwuth et al. 2006). In this study we tested this possibility for the human triceps surae muscles
Segmented scintillation detectors with silicon photomultiplier readout for measuring antiproton annihilations
The Atomic Spectroscopy and Collisions Using Slow Antiprotons (ASACUSA)
experiment at the Antiproton Decelerator (AD) facility of CERN constructed
segmented scintillators to detect and track the charged pions which emerge from
antiproton annihilations in a future superconducting radiofrequency Paul trap
for antiprotons. A system of 541 cast and extruded scintillator bars were
arranged in 11 detector modules which provided a spatial resolution of 17 mm.
Green wavelength-shifting fibers were embedded in the scintillators, and read
out by silicon photomultipliers which had a sensitive area of 1 x 1 mm^2. The
photoelectron yields of various scintillator configurations were measured using
a negative pion beam of momentum p ~ 1 GeV/c. Various fibers and silicon
photomultipliers, fiber end terminations, and couplings between the fibers and
scintillators were compared. The detectors were also tested using the
antiproton beam of the AD. Nonlinear effects due to the saturation of the
silicon photomultiplier were seen at high annihilation rates of the
antiprotons.Comment: Copyright 2014 American Institute of Physics. This article may be
downloaded for personal use only. Any other use requires prior permission of
the author and the American Institute of Physics. The following article
appeared in Review of Scientific Instruments, Vol.85, Issue 2, 2014 and may
be found at http://dx.doi.org/10.1063/1.486364
Size dependent line broadening in the emission spectra of single GaAs quantum dots: Impact of surface charges on spectral diffusion
Making use of droplet epitaxy, we systematically controlled the height of
self-assembled GaAs quantum dots by more than one order of magnitude. The
photoluminescence spectra of single quantum dots revealed the strong dependence
of the spectral linewidth on the dot height. Tall dots with a height of ~30 nm
showed broad spectral peaks with an average width as large as ~5 meV, but
shallow dots with a height of ~2 nm showed resolution-limited spectral lines
(<120 micro eV). The measured height dependence of the linewidths is in good
agreement with Stark coefficients calculated for the experimental shape
variation. We attribute the microscopic source of fluctuating electric fields
to the random motion of surface charges at the vacuum-semiconductor interface.
Our results offer guidelines for creating frequency-locked photon sources,
which will serve as key devices for long-distance quantum key distribution.Comment: 6 pages, 6 figures; updated figs and their description
Beam Performance of Tracking Detectors with Industrially Produced GEM Foils
Three Gas-Electron-Multiplier tracking detectors with an active area of 10 cm
x 10 cm and a two-dimensional, laser-etched orthogonal strip readout have been
tested extensively in particle beams at the Meson Test Beam Facility at
Fermilab. These detectors used GEM foils produced by Tech-Etch, Inc. They
showed an efficiency in excess of 95% and spatial resolution better than 70 um.
The influence of the angle of incidence of particles on efficiency and spatial
resolution was studied in detail.Comment: 8 pages, 9 figures, accepted by Nuclear Instruments and Methods in
Physics Research
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