相关论文: SPIN Effects, QCD, and Jefferson Laboratory with 1…
After the initial discovery of the so-called "spin crisis in the parton model" in the 1980's, a large set of polarization data in deep inelastic lepton-nucleon scattering was collected at labs like SLAC, DESY and CERN. More recently, new…
Double-polarization asymmetries for inclusive $ep$ scattering were measured at Jefferson Lab using 2.6 and 4.3 GeV longitudinally polarized electrons incident on a longitudinally polarized NH$_3$ target in the CLAS detector. The polarized…
This is an introductory review of central topics in hadron physics that are addressed by high intensity, continuous electron beam facilities in the multi-GeV range. Exclusive processes are a crucial tool for increasing our knowledge of…
Developments in strangeness photo- and electro- production off the proton, as investigated using the CLAS system in Hall B at Jefferson Lab, are discussed in this paper. By measuring sufficient spin observables one can decompose the…
Hadron masses under strong magnetic fields are studied. In the presence of strong magnetic fields exceeding the QCD energy scale $ eB \gg \Lambda^2_{\rm QCD} $, ${\rm SU(3)}_{\rm flavor} \otimes {\rm SU(2)}_{\rm spin}$ symmetry of hadrons…
We study multi-hadron systems with a single heavy quark (charm or bottom) in the limit of heavy quark mass. The spin degeneracy of the states with quantum numbers $(j+1/2)^{P}$ and $(j-1/2)^{P}$ for $j \neq 0$, known in a normal hadron, can…
We discuss the Jefferson Lab low momentum transfer data on moments of the nucleon spin structure functions $g_1$ and $g_2$ and on single charged pion electroproduction off polarized proton and polarized neutron. A wealth of data is now…
Rather than regarding the restriction of current lattice QCD simulations to quark masses that are 5--10 times larger than those observed, we note that this presents a wonderful opportunity to deepen our understanding of QCD. Just as it has…
This article reviews our present understanding of the QCD spin structure of the proton. We first outline the proton spin puzzle and its possible resolution in QCD. We then review the present and next generation of experiments to resolve the…
Nucleon structure study is one of the most important research areas in modern physics and has challenged us for decades. Spin has played an essential role and often brought surprises and puzzles to the investigation of the nucleon structure…
We summarize the developments on the structure of the proton that were studied at the Workshop on "HERA Physics" that was held in Durham in September 1995. We survey the latest structure function data; we overview the QCD interpretations of…
This is a review of hadron structure physics from lattice QCD. Throughout this report, we place emphasis on the contribution of lattice results to our understanding of a number of fundamental physics questions related to, e.g., the origin…
The Jefferson Lab PAC recently approved an experiment which will use an enhanced tensor po- larized solid target. This exciting development holds the potential of initiating a new field of tensor spin physics at JLab. Experiments which…
The calculation of the strangeness content of the nucleon and its experimental verification is a fundamental step in establishing non-perturbative QCD as the correct theory describing the structure of hadrons. It holds a role in QCD…
Lepto-nuclear colliders offer unique experimental opportunities to probe QCD in an extended medium. Of the many possibilities, three experiments are described here that are clearly feasible and of high scientific importance. First, a direct…
Large-distance effects, which lead to the spin-flip part of the hadron -pomeron coupling in QCD -models, are discussed. We study spin asymmetries in exclusive reactions and in diffractive $Q \bar Q$ and vector meson production which are…
We present the recent data issued from the Halls A and B of Jefferson Laboratory for the Deep Virtual Compton Scattering Process on the proton. An important set of data for beam spin asymmetries, unpolarized cross sections and differences…
Recent progress in understanding the strong physics regime of QCD is described. The role played by condensates, particularly $q{\bar q}$, in breaking chiral symmetry and generating constituent masses for $u$ and $d$ quarks is reviewed. The…
I discuss how global QCD fits of parton distribution functions can make the somewhat separated fields of high-energy particle physics and lower energy hadronic and nuclear physics interact to the benefit of both. I review specific examples…
We present a first QCD analysis of next-to-next-leading-order (NNLO) contributions of the spin-dependent parton distribution functions (PPDFs) in the nucleon and their uncertainties using the Jacobi polynomial approach. Having the NNLO…