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تسجيل مستخدم جديدA direct measurement of short range NN correlations in nuclei via the reaction C(p,2p+n)
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The reaction 12C(p,2p+n) was measured at beam momenta of 5.9 and 7.5 GeV/c.. We established the quasi-elastic character of the reaction C(p,2p) at $theta_{cm}simeq 90^o$, in a kinematically complete measurement. The neutron momentum was measured in triple coincidence with the two emerging high momentum protons. We present the correlation between the momenta of the struck target proton and the neutron. The events are associated with the high momentum components of the nuclear wave function. We conclude that two-nucleon short range correlations have been seen experimentally. The conclusion is based on kinematical correlations and is not based on specific theoretical models.
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We studied the $^{12}$C(p,2p+n) reaction at beam momenta of 5.9, 8.0 and 9.0 GeV/c. For quasielastic (p,2p) events we reconstructed {bf p_f} the momentum of the knocked-out proton before the reaction; {bf p_f} was then compared (event-by-event) with
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ta from new measurement by the collaboration, utilizing the same technique. This technique is based on a very simple kinematic approach. For quasi-elastic knockout of protons from a nucleus ($^{12}$C(p,2p) was used for the current work), we can reconstruct the momentum {bf p$_f$} of the struck proton in the nucleus before the reaction, from the three momenta of the two detected protons, {bf p$_1$} and {bf p$_2$} and the three momentum of the incident proton, {bf p$_0$} : {bf p$_f$} = {bf p$_1$} + {bf p$_2$} - {bf p$_0$} If there are significant n-p SRCs, then we would expect to find a neutron with momentum -{bf p$_f$} in coincidence with the two protons, provided {bf p$_f$} is larger than the Fermi momentum $k_F$ for the nucleus (${sim}$220 MeV/c for $^{12}$C). Our results reported here confirm the earlier results from the E850 collaboration.
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