اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدLongitudinal double-spin asymmetry $A_1^{rm p}$ and spin-dependent structure function $g_1^{rm p}$ of the proton at small values of $x$ and $Q^2$
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We present a precise measurement of the proton longitudinal double-spin asymmetry $A_1^{rm p}$ and the proton spin-dependent structure function $g_1^{rm p}$ at photon virtualities $0.006~({rm GeV}/c)^2<Q^2 < 1~({rm GeV}/c)^2$ in the Bjorken $x$ range of $4 times 10^{-5} < x < 4 times 10^{-2}$. The results are based on data collected by the COMPASS Collaboration at CERN using muon beam energies of $160~{rm GeV}$ and $200~{rm GeV}$. The statistical precision is more than tenfold better than that of the previous measurement in this region. In the whole range of $x$, the measured values of $A_1^{rm p}$ and $g_1^{rm p}$ are found to be positive. It is for the first time that spin effects are found at such low values of $x$.
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New results for the double spin asymmetry $A_1^{rm p}$ and the proton longitudinal spin structure function $g_1^{rm p}$ are presented. They were obtained by the COMPASS collaboration using polarised 200 GeV muons scattered off a longitudinally polari
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