In-flight dark current nonuniformity measurements performed on three different satellites JASON-2, SPRINT-A, and SAT-X (name withheld) are compared to ground calculations. The standard deviation of ...the DCNU is calculated using both the AP8 and AP9 environment models. These predictions are compared to some calculations made with proton fluxes measured with the Influence sur les Composants Avancés des Radiations de l'Espace-NG spectrometer embedded on the JASON-2 satellite. The reliability of AP8 and AP9 models is analyzed. AP9 model appears to consistently overestimate the in-flight degradation.
The present experiment exploits the interference between the deeply virtual Compton scattering (DVCS) and the Bethe-Heitler processes to extract the imaginary part of DVCS amplitudes on the neutron ...and on the deuteron from the helicity-dependent D(e,e'gamma)X cross section measured at Q2=1.9 GeV2 and xB=0.36. We extract a linear combination of generalized parton distributions (GPDs) particularly sensitive to E_{q}, the least constrained GPD. A model dependent constraint on the contribution of the up and down quarks to the nucleon spin is deduced.
The 3D Monte Carlo transport code GEANT 4 was used to simulate the Dark Current Non Uniformity of image sensors. The method includes three different physical processes: the Coulombic scattering, the ...nuclear elastic interaction and the nuclear inelastic interaction. The dark current distribution is directly deduced from the damage distribution according to the Universal Damage Factor of Srour (UDF). Comparisons have been performed with experimental measurements made on two CMOS Image Sensors (JADE from E2 V and HAS2 from ON SEMICONDUCTOR) irradiated with protons of various energies ranging from 30 MeV to 185 MeV. Despite the simplifying assumptions of the model, the calculations are demonstrated to be in quite good agreement with experimental data.
This paper presents experimental data showing heavy ions inducing gate degradation in power MOSFETs. In the experiments, backside and front-side irradiations are performed. During backside ...irradiation, the heavy ion ranges are tuned in such way to control whether they hit the gate or not. Gate-to-source current Igss (Phi) is measured versus heavy ions (H.I.) fluence Phi. Post-irradiation-gate-stress-test (PGST) allows measurement of gate breakdown voltage V BD (Phi) which is observed to decrease with (H.I.) fluence. Based on these experimental results, a hypothesis of substrate-generated carriers impact overlap of multiple strikes may explain gate degradation until SEGR triggering. This last hypothesis is supported by a statistical model approach of heavy ions multiple impacts.
We present the first measurements of the eover -->p-->epgamma cross section in the deeply virtual Compton scattering (DVCS) regime and the valence quark region. The Q(2) dependence (from 1.5 to 2.3 ...GeV(2)) of the helicity-dependent cross section indicates the twist-2 dominance of DVCS, proving that generalized parton distributions (GPDs) are accessible to experiment at moderate Q(2). The helicity-independent cross section is also measured at Q(2)=2.3 GeV(2). We present the first model-independent measurement of linear combinations of GPDs and GPD integrals up to the twist-3 approximation.
Spatially-correlated overabundances of \(^{15}\)N and \(^{18}\)O observed in some low-density graphite meteoritic grains have been connected to nucleosynthesis taking place in the helium-burning ...shell during core-collapse supernovae. Two of the reactions which have been identified as important to the final abundances of \(^{15}\)N and \(^{18}\)O are \(^{18}\)F(\(n,\alpha\))\(^{15}\)N and \(^{18}\)F(\(n,p\))\(^{18}\)O. The relative strengths of the \(^{18}\)F(\(n,\alpha\))\(^{15}\)N and \(^{18}\)F(\(n,p\))\(^{18}\)O reactions depend on the relative \(\alpha_0\) and \(p_0\) decays from states above the neutron threshold in \(^{19}\)F in addition to other properties. Experimental data on the charged-particle decays from these highly excited states are lacking or inconsistent. Two experiments were performed using proton inelastic scattering from LiF targets and magnetic spectrographs. The first experiment used the high-resolution Q3D spectrograph at Munich to constrain properties of levels in \(^{19}\)F. A second experiment using the Orsay Split-Pole spectrograph and an array of silicon detectors was performed in order to measure the charged-particle decays of neutron-unbound levels in \(^{19}\)F. A number of levels in \(^{19}\)F have been identified along with their corresponding charged-particle decays. The first state above the neutron threshold which has an observed proton-decay branch to the ground state of \(^{18}\)O lies 68 keV above the neutron threshold while the \(\alpha\)-particle decays from the neutron-unbound levels are generally observed to be much stronger than the proton decays. Neutron-unbound levels in \(^{19}\)F are observed to decay predominantly by \(\alpha\)-particle emission, supporting the role of \(^{18}\)F(\(n,\alpha\))\(^{15}\)N in the production of \(^{15}\)N in the helium-burning shell of supernovae. Improved resonant-scattering reaction data are required in order to be able to determine the reaction rates accurately.
We present measurements of the ep->ep pi^0 cross section extracted at two values of four-momentum transfer Q^2=1.9 GeV^2 and Q^2=2.3 GeV^2 at Jefferson Lab Hall A. The kinematic range allows to study ...the evolution of the extracted hadronic tensor as a function of Q^2 and W. Results will be confronted with Regge inspired calculations and GPD predictions. An intepretation of our data within the framework of semi-inclusive deep inelastic scattering has also been attempted.
We present final results on the photon electroproduction ($\vec{e}p\rightarrow ep\gamma$) cross section in the deeply virtual Compton scattering (DVCS) regime and the valence quark region from ...Jefferson Lab experiment E00-110. Results from an analysis of a subset of these data were published before, but the analysis has been improved which is described here at length, together with details on the experimental setup. Furthermore, additional data have been analyzed resulting in photon electroproduction cross sections at new kinematic settings, for a total of 588 experimental bins. Results of the $Q^2$- and $x_B$-dependences of both the helicity-dependent and helicity-independent cross sections are discussed. The $Q^2$-dependence illustrates the dominance of the twist-2 handbag amplitude in the kinematics of the experiment, as previously noted. Thanks to the excellent accuracy of this high luminosity experiment, it becomes clear that the unpolarized cross section shows a significant deviation from the Bethe-Heitler process in our kinematics, compatible with a large contribution from the leading twist-2 DVCS$^2$ term to the photon electroproduction cross section. The necessity to include higher-twist corrections in order to fully reproduce the shape of the data is also discussed. The DVCS cross sections in this study represent the final set of experimental results from E00-110, superseding the previous publication.
We present the key results of multiple radiation characterization campaigns of the HAS2 radiation-hardened active pixel sensor (APS). These characterizations encompassed Cobalt-60 total ionizing ...dose, proton and electron displacement damage tests at room and low temperature. This gives us the opportunity to discuss the influence on this APS of two phenomena that had been previously observed on charge coupled devices (CCDs): room temperature displacement damage defect annealing, and non-ionizing energy loss (NIEL) scaling between electron and proton irradiations.
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