5,457 research outputs found
Electromagnetic Form Factors and the Hypercentral CQM
New results about the electromagnetic form factors of the nucleon are
obtained with a semirelativistic version of the hypercentral constituent quark
model (hCQM) and a relativistic current. The complex structure of the
constituent quarks is taken into account implicitly by means of
phenomenological constituent quark form factors. We obtain a detailed
reproduction of the experimental data up to , moreover our findings
about constituent quark root mean square radii are of the same order than the
recent ones obtained analyzing the proton structure functions.Comment: 11 pages, 4 figure
A relativistic study of the nucleon form factors
We perform a calculation of the relativistic corrections to the
electromagnetic elastic form factors of the nucleon obtained with various
Constituent Quark Models. With respect to the non relativistic calculations a
substantial improvement is obtained up to Q^2 about 2 (GeV/c)^2.Comment: 10 pages, 6 figures (1a,1b,1c,2a,2b,2c), to be published on Z. Phys.
Electromagnetic Form Factors and the hCQM
We briefly report on results about the electromagnetic form factors of the
nucleon obtained with different models and then we concentrate our attention on
recent results obtained with the hypercentral constituent quark model (hCQM).Comment: 12 pages, 5 figures, Invited talk at 27th Symposium on Nuclear
Physics, Taxco, Guerrero, Mexico, 5-8 Jan 200
Future Scientific Missions for STS
As the Space Transportation System (STS) transitions to a fully operational system, the opportunities for flying new astrophysics missions in the late eighties and early nineties have greatly increased. Current NASA studies include the analysis of Space Platforms and Space Stations which could become operational systems in the nineties. The Space Shuttle gives the scientific community the capability to fly new astrophysics missions, obtain valuable scientific data, and provide payloads that can transition to Space Platforms and Space Stations. The purpose of this paper is to describe some scientific payloads that are being studied by NASA at the Marshall Space Flight Center (MSFC) . Emphasis will be placed, on showing how these scientific payloads can utilize the Space Shuttle, obtain new data, and through evolution form the nucleus for new astrophysics missions on, a Space Platform or Space Station
Single Spin Asymmetries in Semi-Inclusive Electroproduction: Access to Transversity
We discuss the quark transversity distribution function and a possible way to
access it through the measurement of single spin azimuthal asymmetry in
semi-inclusive single pion electroproduction on a transversely polarized
target.Comment: 5 pages, Latex using aipproc.sty (included), to appear in proceedings
of "Second Workshop on Physics with an Electron Polarized Light Ion
Collider", Sept. 14-16, 2000, MIT, Cambridge, US
- …