Abstract
In constituent quark models, a tensor interaction, mixing quark spins with their relative motion, is introduced to reproduce the observed baryon spectrum. This has a consequence completely analogous to the nuclear tensor force between the n and p in deuterium. A D state component is mixed into what would otherwise be a purely S-wave object. The D-wave component breaks spherical symmetry, resulting in a non-vanishing <r2Y2> matrix element for the nucleon and a static quadrupole moment and deformation for its first excited state, the Δ resonance, at ∽325 MeV. The magnitude and sign of this D-state component are quite sensitive to the internal structure of the proton and have been of great interest in recent years [1].
Keywords
- Compton Scattering
- Cross Section Ratio
- Tensor Interaction
- National Synchrotron Light Source
- Unpolarized Cross Section
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
This is a preview of subscription content, log in via an institution.
Buying options
Tax calculation will be finalised at checkout
Purchases are for personal use only
Learn about institutional subscriptionsPreview
Unable to display preview. Download preview PDF.
References
S.L. Glashow, Physica (Amsterdam) 96A, 27 (1979); M. Giannini, Rep. Prog. Phys. 54, 453 (1991), and references contained therein.
N.C. Mukhopadhyay, in Topical Workshop on Excited Baryons-1988, Troy, NY,, edited by G. Adams, N. Mukhopadhyay, and P. Stoler (World Scientific, Singapore, 1989 ), p. 205.
See, for example H. Tanabe and K. Ohta, Phys. Rev. C31, 1876 (1985); S.N. Yang, J. Phys. G 11, L205 (1985); A.M. Bernstein, S. Nozawa, and M.A. Moinester, Phys. Rev. C47, 1274 (1993).
Private communication; extensions of calculations described in S. Nozawa, B. Blan- kleider and T.-S.H. Lee, Nucl. Phys. A513, 459 (1990).
Private communication; extensions of calculations described in R. Davidson, N. Mukhopadhyay and R. Whittman, Phys. Rev. D43, 71 (1991).
A.M. Sandorfi et al., IEEE Trans. Nucl. Sci. 30, 3083 (1983).
C.E. Thorn et al., Nucl. Instrum. Methods Phys. Res., Sect. A285, 447 (1989).
The LEGS Collaboration, G.S. Blanpied et ai, Phys. Rev. Lett. 69, 1880 (1992).
A.M. Sandorfi et al., in Topical Workshop on Excited Baryons (Ref. [2]), p. 256; W. Pfeil et al, Nucl. Phys. B73, 166 (1974).
V.B. Ganenko et al., Yad. Fiz. 23, 310 (1976) [Sov. J. Nucl. Phys., 23, 162 (1976)].
A.A. Belyaev et al Yad. Fiz. 35, 693 (1982) [Sov. J. Nucl. Phys., 35, 401 (1982)].
F. Berends and A. Donnachie, Nucl. Phys. B84, 342 (1975).
R. Davidson and N. Mukhopadhyay, Phys. Rev. Lett. 70, 3834 (1993); A.M. Sandorfi and M. Khandaker, Phys. Rev. Lett. 70, 3835 (1993).
R.A. Arndt et al., Phys. Rev. D42, 1853 (1990); SP92 solution calculated with the code SAID.
G. Barbiellini et al., Phys. Rev. 174, 1665 (1968).
W. Pfeil, H. Rollnik and S. Stankowski, Nucl. Phys. B73, 166 (1974).
M. Benmerrouche and N.C. Mukhopadhyay, Phys. Rev. D46, 101 (1992).
A.M. Sandorfi, to be published.
H. Genzel et al., Z. Physik A279, 399 (1976).
T. Ishii et al., Nucl. Phys. B165, 189 (1980).