Measurement of the Proton and Deuteron Spin Structure Function g_1 in the Resonance Region

We have measured the proton and deuteron spin structure functions g_1^p and g_1^d in the region of the nucleon resonances for W^2 < 5 GeV^2 and $Q^2\simeq 0.5$ and $Q^2\simeq 1.2$ GeV^2 by inelastically scattering 9.7 GeV polarized electrons off polarized $^{15}NH_3$ and $^{15}ND_3$ targets. We observe significant structure in g_1^p in the resonance region. We have used the present results, together with the deep-inelastic data at higher W^2, to extract $\Gamma(Q^2)\equiv\int_0^1 g_1(x,Q^2) dx$. This is the first information on the low-Q^2 evolution of Gamma toward the Gerasimov-Drell-Hearn limit at Q^2 = 0.Comment: 7 pages, 2 figure

Precision measurement of the deuteron spin structure function g1dg^{d}_{1}

We report on a high-statistics measurement of the deuteron spin structure function g[sup d][sub 1] at a beam energy of 29 GeV in the kinematic range 0.029 < x < 0.8 and 1 < Q2 < 10 (GeV/c)2. The integral Gamma [sup d][sub 1] = (integral)[sup 1][sub 0]g[sup d][sub 1]dx evaluated at fixed Q2 = 3 (GeV/c)2 gives 0.042 ± 0.003(stat) ± 0.004(syst). Combining this result with our earlier measurement of g[sup p][sub 1], we find Gamma [sup p][sub 1]- Gamma [sup n][sub 1] = 0.163 ± 0.010(stat) ± 0.016(syst), which agrees with the prediction of the Bjorken sum rule with O( alpha [sup 3][sub s]) corrections, Gamma [sup p][sub 1]- Gamma [sup n][sub 1] = 0.171 ± 0.008. We find the quark contribution to the proton helicity to be Delta q = 0.30 ± 0.06

Measurements of the Proton and Deuteron Spin Structure Functions g1g_{1} and g2g_{2}

Measurements are reported of the proton and deuteron spin structure functions g1 at beam energies of 29.1, 16.2, and 9.7 GeV and g2 at a beam energy of 29.1 GeV. The integrals of g1 over x have been evaluated at fixed Q**2 = 3 (GeV/c)**2 using the full data set. The Q**2 dependence of the ratio g1/F1 was studied and found to be small for Q**2 > 1 (GeV/c)**2. Within experimental precision the g2 data are well-described by the Wandzura-Wilczek twist-2 contribution. Twist-3 matrix elements were extracted and compared to theoretical predictions. The asymmetry A2 was measured and found to be significantly smaller than the positivity limit for both proton and deuteron targets. A2 for the proton is found to be positive and inconsistent with zero. Measurements of g1 in the resonance region show strong variations with x and Q**2, consistent with resonant amplitudes extracted from unpolarized data. These data allow us to study the Q**2 dependence of the first moments of g1 below the scaling region

Measurements of R=sigma_L/sigma_T for 0.03<x<0.1 and Fit to World Data

Measurements were made at SLAC of the cross section for scattering 29 GeV electrons from carbon at a laboratory angle of 4.5 degrees, corresponding to 0.03<x<0.1 and 1.3<Q^2<2.7 GeV^2. Values of R=sigma_L/sigma_T were extracted in this kinematic range by comparing these data to cross sections measured at a higher beam energy by the NMC collaboration. The results are in reasonable agreement with pQCD calculations and with extrapolations of the R1990 parameterization of previous data. A new fit is made including these data and other recent results.Comment: 8 pages, 4 figures, late

Etude experimentale de production de pion neutre dans l'interaction proton-proton a energie de faisceau = 800 MeV . Reaction (pp→ppπ0)(pp\rightarrow pp\pi^0) avec le detecteur DIOGENE

Once out of workplaces where speech cannot play anymore its full role on immediate readjusting or producing agreements on the meaning of the situation a large part of language production is supported by written material. In this paper we will focus on documents seen as intermediary objects, and forms investment. We will question the different spatial allocations given to workers. How do these allocations affect forms of “working together” in an organisation

All-<i>trans</i>-retinoic acid regulates aquaporin-3 expression and related cellular membrane permeability in the human amniotic environment

International audienceThe aquaporins (AQP1, 3, 8, 9 and 11) are known to be expressed, and involved in the transport of water and small molecules through fetal membranes. To exert these crucial functions, these AQPs have to be finely regulated. All-trans-retinoic acid (atRA) was previously found to regulate some genes in this environment, raising the question of whether these AQPs were regulated by atRA

Do clusters generate greater innovation and growth? An analysis of European regions

The analysis of clusters has attracted considerable interest over the last few decades. The articulation of clusters into complex networks and systems of innovation-generally known as regional innovation systems-has, in particular, been associated with the delivery of greater innovation and growth. Despite the growing economic and policy relevance of clusters, little systematic research has been conducted into their association with other factors promoting innovation and economic growth. This article addresses this issue by looking at the relationship between innovation and economic growth in 152 regions of Europe during the period between 1995 and 2006. Using an econometric model with a static and a dynamic dimension, the results of the analysis highlight that (1) regional growth through innovation in Europe is fundamentally connected to the presence of an adequate socioeconomic environment and, in particular, to the existence of a well-trained and educated pool of workers; (2) the presence of clusters matters for regional growth but only in combination with a good social filter, and this association wanes in time; (3) more traditional research and development variables have a weak initial connection to economic development, but this connection increases over time and is, once again, contingent on the existence of adequate socioeconomic conditions

A study of the pp→ppπ0pp\rightarrow pp\pi^0 reaction at 800 MeV beam energy using the DIOGENE detector at SATURNE

International audienceThe reaction pp→pp$\pi$$^0$ has been investigated at the Satume accelerator using a transversely polarized beam of 800 MeV incident kinetic energy and the DIOGENE detector. We have measured the total cross section, the differential cross section as a function of the pion energy and the anisotropy parameter b. We find a strongly dominant contribution, greater than 90%, of the Delta resonance to this process. We have determined the analyzing power A$_y$ of the reaction and get negative values