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تسجيل مستخدم جديدStudying Short-Range Correlations with Real Photon Beams at GlueX
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The past few years has seen tremendous progress in our understanding of short-range correlated (SRC) pairing of nucleons within nuclei, much of it coming from electron scattering experiments leading to the break-up of an SRC pair. The interpretation of these experiments rests on assumptions about the mechanism of the reaction. These assumptions can be directly tested by studying SRC pairs using alternate probes, such as real photons. We propose a 30-day experiment using the Hall D photon beam, nuclear targets, and the GlueX detector in its standard configuration to study short-range correlations with photon-induced reactions. Several different reaction channels are possible, and we project sensitivity in most channels to equal or exceed the 6 GeV-era SRC experiments from Halls A and B. The proposed experiment will therefore decisively test the phenomena of np dominance, the short-distance NN interaction, and reaction theory, while also providing new insight into bound nucleon structure and the onset of color transparency.
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The experiment, E08-014, in Hall-A at Jefferson Lab aims to study the short-range correlations (SRC) which are necessary to explain the nuclear strength absent in the mean field theory. The cross sections for $mathrm{^{2}H}$, $mathrm{^{3}He}$, $mathr
m{^{4}He}$, $mathrm{^{12}C}$, $mathrm{^{40}Ca}$ and $mathrm{^{48}Ca}$, were measured via inclusive quasielastic electron scattering from these nuclei in a $mathrm{Q^{2}}$ range between 0.8 and $mathrm{2.8~(GeV/c)^{2}}$ for $x_{bj}>1$. The cross section ratios of heavy nuclei to $mathrm{^{2}H}$ were extracted to study two-nucleon SRC for $1<x_{bj}<2$, while the study of three-nucleon SRC was carried out from the cross section ratios of heavy nuclei to $mathrm{^{3}He}$ for $x_{bj}ge 2$. Meanwhile, the isospin dependence in SRCs has also been examined through the cross section ratio of $mathrm{^{48}Ca}$ and $mathrm{^{40}Ca}$.
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We present new data probing short-range correlations (SRCs) in nuclei through the measurement of electron scattering off high-momentum nucleons in nuclei. The inclusive 4He/3He cross section ratio is observed to be both x and Q2 independent for 1.5 <
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