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The protons and neutrons in a nucleus can form strongly correlated nucleon pairs. Scattering experiments, in which a proton is knocked out of the nucleus with high-momentum transfer and high missing momentum, show that in carbon-12 the neutron-proton pairs are nearly 20 times as prevalent as proton-proton pairs and, by inference, neutron-neutron pairs. This difference between the types of pairs is due to the nature of the strong force and has implications for understanding cold dense nuclear sys

We present measurements of the ratio of the proton elastic electromagnetic form factors, ${\ensuremath{\mu}}_{p}{G}_{\mathrm{Ep}}{/G}_{\mathrm{Mp}}.$ The Jefferson Lab Hall A Focal Plane Polarimeter was used to determine the longitudinal and transverse components of the recoil proton polarization in $\mathrm{ep}$ elastic scattering; the ratio of these polarization components is proportional to the ratio of the two form factors. These data reproduce the observation of Jones et al. [Phys. Rev. Let

We report on measurements of the neutron spin asymmetries ${A}_{1,2}^{n}$ and polarized structure functions ${g}_{1,2}^{n}$ at three kinematics in the deep inelastic region, with $x=0.33$, 0.47, and 0.60 and ${Q}^{2}=2.7$, 3.5, and $4.8\phantom{\rule{0.3em}{0ex}}{(\mathrm{GeV}∕c)}^{2}$, respectively. These measurements were performed using a $5.7\phantom{\rule{0.3em}{0ex}}\mathrm{GeV}$ longitudinally polarized electron beam and a polarized $^{3}\mathrm{He}$ target. The results for ${A}_{1}^{n}$

We have analyzed data of the DISTO experiment on the exclusive pp --> pLambdaK+ reaction at 2.85 GeV to search for a strongly bound compact K- pp(approximately = X) state to be formed in the pp --> K+ + X reaction. The observed spectra of the K+ missing mass and the pLambda invariant-mass with high transverse momenta of p and K+ revealed a broad distinct peak of 26-sigma confidence with a mass M(X)=2267+/-3(stat)+/-5(syst) MeV/c2 and a width Gamma(X)=118+/-8(stat)+/-10(syst) MeV. The enormously

We investigated simultaneously the 12C(e,e'p) and 12C(e,e'pp) reactions at Q2=2 (GeV/c)2, xB=1.2, and in an (e, e'p) missing-momentum range from 300 to 600 MeV/c. At these kinematics, with a missing momentum greater than the Fermi momentum of nucleons in a nucleus and far from the delta excitation, short-range nucleon-nucleon correlations are predicted to dominate the reaction. For (9.5+/-2)% of the 12C(e,e'p) events, a recoiling partner proton was observed back-to-back to the 12C(e,e'p) missing

We have measured the parity-violating electroweak asymmetry in the elastic scattering of polarized electrons from 4He at an average scattering angle <theta(lab)> = 5.7 degrees and a four-momentum transfer Q2 = 0.091 GeV2 . From these data, for the first time, the strange electric form factor of the nucleon G(E)s can be isolated. The measured asymmetry of A(PV) = (6.72 +/- 0.84(stat) +/- 0.21(syst) x 10(-6) yields a value of G(E)s = -0.038 +/- 0.042(stat) +/- 0.010(syst), consistent with zero.

We report the most precise measurement to date of a parity-violating asymmetry in elastic electron–proton scattering. The measurement was carried out with a beam energy of 3.03 GeV and a scattering angle 〈θlab〉=6.0○, with the result APV=(−1.14±0.24(stat)±0.06(syst))×10−6. From this we extract, at Q2=0.099GeV2, the strange form factor combination GEs+0.080GMs=0.030±0.025(stat)±0.006(syst)±0.012(FF) where the first two errors are experimental and the last error is due to the uncertainty in the neu

We have measured the neutron spin asymmetry A(n)(1) with high precision at three kinematics in the deep inelastic region at x=0.33, 0.47, and 0.60, and Q(2)=2.7, 3.5, and 4.8 (GeV/c)(2), respectively. Our results unambiguously show, for the first time, that A(n)(1) crosses zero around x=0.47 and becomes significantly positive at x=0.60. Combined with the world proton data, polarized quark distributions were extracted. Our results, in general, agree with relativistic constituent quark models and

The exclusive production cross sections for $\ensuremath{\omega}$ and $\ensuremath{\varphi}$ mesons have been measured in proton-proton reactions at ${p}_{\mathrm{lab}}=3.67 \mathrm{GeV}/c.$ The observed $\ensuremath{\varphi}/\ensuremath{\omega}$ cross section ratio is $(3.8\ifmmode\pm\else\textpm\fi{}{0.2}_{\ensuremath{-}0.9}^{+1.2})\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3}.$ After phase space corrections, this ratio is enhanced by about an order of magnitude relative to naive pr

The cross section for exclusive ${\mathrm{\ensuremath{\pi}}}^{+}$ electroproduction on the proton has been measured near threshold for the first time at two different values of the virtual photon polarization (\ensuremath{\varepsilon}\ensuremath{\sim}0.2 and \ensuremath{\varepsilon}\ensuremath{\sim}0.7). Using the low energy theorem for this reaction we deduce the axial and pseudoscalar weak form factors ${\mathit{G}}_{\mathit{A}}$ and ${\mathit{G}}_{\mathit{P}}$ at \ensuremath{\Vert}t\ensuremat

We developed an Application Programming Interface (API) tracing tool for Android-based mobile devices. This tool has the capability of generating trace files by remotely monitoring and recording API calls made by an app running on a mobile device. In addition, the automatic feature of the tool allows repeated tracing tasks to be conducted without user's intervention against a collection of apps. The trace data may be effectively utilized in analyzing app's behavior and intentions, which will pro

Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Twitter Facebook Reddit LinkedIn Tools Icon Tools Reprints and Permissions Cite Icon Cite Search Site Citation Seonho Choi, Jefferson Lab SANE Collaboration; Spin Asymmetries on Nucleon Experiment at Jefferson Lab. AIP Conf. Proc. 21 October 2011; 1388 (1): 480–483. https://doi.org/10.1063/1.3647435 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers

The upcoming experiment at Jeferson Lab will make a precision measurement of inclusive electron scatering cros sections in the quasi-elastic region for a wide range of momentum transfers for 4He, 12C, 56Fe and 208Pb. The extracted longitudinal and transverse response functions in the momentum transfer range 0:55 GeV/c ≤ |q| ≤ 0.9 GeV/c with an eror of a few percent wil improve significantly the precision of the Coulomb sum rule measurements. This should alow us to conrm/refute the presently cont