We present data on the inclusive scattering of polarized electrons from a polarized He-3 target at energies from 0.862 to 5.06 GeV, obtained at a scattering angle of 15.5 degrees. Our data include ...measurements from the quasielastic peak, through the resonance region, to the beginning of the deep inelastic regime, and were used to determine the spin difference in the virtual photoabsorption cross section. We extract the extended Gerasimov-Drell-Hearn integral for the neutron in the range of 4-momentum transfer squared Q^2 of 0.1-0.9 GeV.
Phys.Rev.Lett.92:022301,2004 We have measured the spin structure functions $g_1$ and $g_2$ of $^3$He in a
double-spin experiment by inclusively scattering polarized electrons at
energies ranging from ...0.862 to 5.07 GeV off a polarized $^3$He target at a
15.5$^{\circ}$ scattering angle. Excitation energies covered the resonance and
the onset of the deep inelastic regions. We have determined for the first time
the $Q^2$ evolution of $\Gamma_1(Q^2)=\int_0^{1} g_1(x,Q^2) dx$,
$\Gamma_2(Q^2)=\int_0^1 g_2(x,Q^2) dx$ and $d_2 (Q^2) = \int_0^1 x^2
2g_1(x,Q^2) + 3g_2(x,Q^2) dx$ for the neutron in the range 0.1 GeV$^2$ $\leq
Q^2 \leq $ 0.9 GeV$^2$ with good precision. $ \Gamma_1(Q^2)$ displays a smooth
variation from high to low $Q^2$. The Burkhardt-Cottingham sum rule holds
within uncertainties and $d_2$ is non-zero over the measured range.
We have measured the 3He(e,e'pp)n reaction at an incident energy of 4.7 GeV over a wide kinematic range. We identified spectator correlated pp and pn nucleon pairs using kinematic cuts and measured ...their relative and total momentum distributions. This is the first measurement of the ratio of pp to pn pairs as a function of pair total momentum, \(p_{tot}\). For pair relative momenta between 0.3 and 0.5 GeV/c, the ratio is very small at low \(p_{tot}\) and rises to approximately 0.5 at large \(p_{tot}\). This shows the dominance of tensor over central correlations at this relative momentum.
The occurrence of serological markers of hepatitis B virus infection among the members of a newly formed community (370 persons) was determined. The markers were detected with the use of highly ...sensitive methods for the detection of HBsAg, anti-HBs, HBeAg, anti-HBc, IgM anti-HBc. At the time of the formation of this community HBsAg, anti-HBs and anti-HBc were detected, respectively, in 4%, 11% and 31.3% and 6 months later, in 8.4%, 9.5% and 46.4% of persons. The presence of a considerable number of inapparent forms of hepatitis B and differences in the degree of the involvement of individual groups in this community into the epidemic process have been shown.
We present measurements of the recoil proton polarization for the d(γ⃗,p⃗)n reaction at θc.m. = 90° for photon energies up to 2.4 GeV. These are the first data in this reaction for polarization ...transfer with circularly polarized photons. The induced polarization py vanishes above 1 GeV, contrary to meson-baryon model expectations, in which resonances lead to large polarizations. However, the polarization transfer Cx does not vanish above 1 GeV, inconsistent with hadron helicity conservation. Thus, we show that the scaling behavior observed in the d(γ,p)ncross sections is not a result of perturbative QCD. These data should provide important tests of new nonperturbative calculations in the intermediate energy regime.
We have measured the spin structure functions \(g_1\) and \(g_2\) of \(^3\)He in a double-spin experiment by inclusively scattering polarized electrons at energies ranging from 0.862 to 5.07 GeV off ...a polarized \(^3\)He target at a 15.5\(^{\circ}\) scattering angle. Excitation energies covered the resonance and the onset of the deep inelastic regions. We have determined for the first time the \(Q^2\) evolution of \(\Gamma_1(Q^2)=\int_0^{1} g_1(x,Q^2) dx\), \(\Gamma_2(Q^2)=\int_0^1 g_2(x,Q^2) dx\) and \(d_2 (Q^2) = \int_0^1 x^2 2g_1(x,Q^2) + 3g_2(x,Q^2) dx\) for the neutron in the range 0.1 GeV\(^2\) \(\leq Q^2 \leq \) 0.9 GeV\(^2\) with good precision. \( \Gamma_1(Q^2)\) displays a smooth variation from high to low \(Q^2\). The Burkhardt-Cottingham sum rule holds within uncertainties and \(d_2\) is non-zero over the measured range.
We present a measurement of the spin-dependent cross sections for the \vec{^3He}(\vec{e},e')X} reaction in the quasielastic and resonance regions at four-momentum transfer 0.1 < Q^2< 0.9 GeV^2. The ...spin-structure functions have been extracted and used to evaluate the nuclear Burkhardt--Cottingham and extended GDH sum rules for the first time. Impulse approximation and exact three-body Faddeev calculations are also compared to the data in the quasielastic region.
Nucl.Instrum.Meth. A540 (2005) 305-310 This paper describes the use of the time-of-flight (TOF) technique as a
particle identification method for the HERMES experiment. The time-of-flight is
measured ...by two 1x4 m^2 scintillation hodoscopes that initially were designed
for the first-level trigger only. However, the suitable time structure of the
HERA electron beam allows an extension of their functions to also measure the
TOF for low momentum hadron identification. Using only these conventional
hodoscopes, good particle identification was achieved for protons and pions in
the momentum range up to 2.9GeV/c and for kaons up to 1.5GeV/c.
This paper describes the use of the time-of-flight (TOF) technique as a particle identification method for the HERMES experiment. The time-of-flight is measured by two 1x4 m^2 scintillation ...hodoscopes that initially were designed for the first-level trigger only. However, the suitable time structure of the HERA electron beam allows an extension of their functions to also measure the TOF for low momentum hadron identification. Using only these conventional hodoscopes, good particle identification was achieved for protons and pions in the momentum range up to 2.9GeV/c and for kaons up to 1.5GeV/c.
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