5 research outputs found
1H, 13C, and 15N backbone chemical shift assignments of m7GTP cap-bound Leishmania initiation factor 4E-1
WEDM of complex profile of IN718: multi-objective GA-based optimization of surface roughness, dimensional deviation, and cutting speed
Beam-helicity asymmetry arising from deeply virtual Compton scattering measured with kinematically complete event reconstruction
The beam-helicity asymmetry in exclusive electroproduction of real photons by
the longitudinally polarized HERA positron beam scattering off an unpolarized
hydrogen target is measured at HERMES. The asymmetry arises from deeply virtual
Compton scattering and its interference with the Bethe--Heitler process.
Azimuthal amplitudes of the beam-helicity asymmetry are extracted from a data
sample consisting of events with detection of all
particles in the final state including the recoiling proton. The installation
of a recoil detector, while reducing the acceptance of the experiment, allows
the elimination of background from events, which
was estimated to contribute an average of about 12% to the signal in previous
HERMES publications. The removal of this background from the present data
sample is shown to increase the magnitude of the leading asymmetry amplitude by
0.054 +/- 0.016 to -0.328 +/- 0.027 (stat.) +/- 0.045 (syst.)
Inclusive Measurements of Inelastic Electron and Positron Scattering from Unpolarized Hydrogen and Deuterium Targets
Results of inclusive measurements of inelastic electron and positron
scattering from unpolarized protons and deuterons at the HERMES experiment are
presented. The structure functions and are determined using a
parameterization of existing data for the longitudinal-to-transverse
virtual-photon absorption cross-section ratio. The HERMES results provide data
in the ranges and 0.1 GeV 20 GeV,
covering the transition region between the perturbative and the
non-perturbative regimes of QCD in a so-far largely unexplored kinematic
region. They are in agreement with existing world data in the region of
overlap. The measured cross sections are used, in combination with data from
other experiments, to perform fits to the photon-nucleon cross section using
the functional form of the ALLM model. The deuteron-to-proton cross-section
ratio is also determined.Comment: 38 pages, 11 Figures, 9 Tables; Fig. 9 modified, Ref. [46] added,
minor textual additions on pages 12 and 1
Leading-Order Determination of the Gluon Polarization from high-PT Hadron Electroproduction
Longitudinal double-spin asymmetries of charged hadrons with high transverse
momentum have been measured in electroproduction using the \hermes\
detector at \hera. Processes involving gluons in the nucleon have been enhanced
relative to others by selecting hadrons with typically above 1 GeV. In
this kinematic domain the gluon polarization has been extracted in leading
order making use of the model embedded in the Monte Carlo Generator \Pythia\
6.2. The gluon polarization obtained from single inclusive hadrons in the
range 1 GeV 2.5 GeV using a deuterium target is at a scale
\la\mu^2\ra=1.35~{\rm GeV}^2 and . For different
final states and kinematic domains, consistent values of \DGG\ have been found
within statistical uncertainties using hydrogen and deuterium targets