E99-107 CLAS experiment
- Spokespersons
- V. D. Burkert, R. Minehart
- Year
- 2005
- Abstract
- An extensive program is currently underway at the Jefferson Laboratory to study the excitation of nucleon resonances with electromagnetic probes. The CEBAF Large Acceptance spectrometer (CLAS) is well suited for the study of a broad rang of kinematics in the invariant mass W, photon virtuality Q^2, and has nearly complete angular coverage for the hadronic resonance decays. Until recently most of the resonance studies using electron beams have employed the single pi0 or eta channels to study the lower mass states, especially the Delta(1232) and the S_11(1535). Many of the higher mass resonances are isospin 1/2 states and couple more strongly to the n pi+ channel. The extraction of resonance information requires the analysis of the angular distribution in the hadronic center-of-mass system. With CLAS this channel becomes now fully accessible as the pi+ is measured in nearly the full azimuthal and polar angular ranges. High statistics data have been taken with a variety of beam energies ranging from 1.5 GeV to 5.75 GeV covering a Q^2 range from 0.3 to 3 GeV^2, and the full resonance mass range. The electron beam was polarized at about 70%. Data on invariant mass distributions for e p -> e' pi+ n is presented in this thesis. Three resonant enhancement can clearly be identified in all data sets belonging to the Delta(1232), D_13(1520), and F_15(1680) resonances. The latter two exhibit Q^2-dependences which are quite different from the Delta(1232).
- Quantities
- dσ/dΩ
Measurements
ID | Quantity | Beam | Target | Final state |
Q2min, GeV2 |
Q2max, GeV2 |
Wmin, GeV |
Wmax, GeV |
---|---|---|---|---|---|---|---|---|
E14M1 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.15 | 1.15 |
E14M2 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.17 | 1.17 |
E14M3 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.19 | 1.19 |
E14M4 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.21 | 1.21 |
E14M5 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.23 | 1.23 |
E14M6 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.25 | 1.25 |
E14M7 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.27 | 1.27 |
E14M8 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.29 | 1.29 |
E14M9 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.31 | 1.31 |
E14M10 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.33 | 1.33 |
E14M11 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.35 | 1.35 |
E14M12 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.37 | 1.37 |
E14M13 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.39 | 1.39 |
E14M14 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.41 | 1.41 |
E14M15 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.43 | 1.43 |
E14M16 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.45 | 1.45 |
E14M17 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.47 | 1.47 |
E14M18 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.49 | 1.49 |
E14M19 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.51 | 1.51 |
E14M20 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.53 | 1.53 |
E14M21 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.55 | 1.55 |
E14M22 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.57 | 1.57 |
E14M23 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.59 | 1.59 |
E14M24 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.61 | 1.61 |
E14M25 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.63 | 1.63 |
E14M26 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.65 | 1.65 |
E14M27 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.67 | 1.67 |
E14M28 | dσ/dΩ | e | p | π+n | 1.72 | 1.72 | 1.69 | 1.69 |
E14M29 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.15 | 1.15 |
E14M30 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.17 | 1.17 |
E14M31 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.19 | 1.19 |
E14M32 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.21 | 1.21 |
E14M33 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.23 | 1.23 |
E14M34 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.25 | 1.25 |
E14M35 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.27 | 1.27 |
E14M36 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.29 | 1.29 |
E14M37 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.31 | 1.31 |
E14M38 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.33 | 1.33 |
E14M39 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.35 | 1.35 |
E14M40 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.37 | 1.37 |
E14M41 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.39 | 1.39 |
E14M42 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.41 | 1.41 |
E14M43 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.43 | 1.43 |
E14M44 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.45 | 1.45 |
E14M45 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.47 | 1.47 |
E14M46 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.49 | 1.49 |
E14M47 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.51 | 1.51 |
E14M48 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.53 | 1.53 |
E14M49 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.55 | 1.55 |
E14M50 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.57 | 1.57 |
E14M51 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.59 | 1.59 |
E14M52 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.61 | 1.61 |
E14M53 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.63 | 1.63 |
E14M54 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.65 | 1.65 |
E14M55 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.67 | 1.67 |
E14M56 | dσ/dΩ | e | p | π+n | 2.05 | 2.05 | 1.69 | 1.69 |
E14M57 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.15 | 1.15 |
E14M58 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.17 | 1.17 |
E14M59 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.19 | 1.19 |
E14M60 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.21 | 1.21 |
E14M61 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.23 | 1.23 |
E14M62 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.25 | 1.25 |
E14M63 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.27 | 1.27 |
E14M64 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.29 | 1.29 |
E14M65 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.31 | 1.31 |
E14M66 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.33 | 1.33 |
E14M67 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.35 | 1.35 |
E14M68 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.37 | 1.37 |
E14M69 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.39 | 1.39 |
E14M70 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.41 | 1.41 |
E14M71 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.43 | 1.43 |
E14M72 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.45 | 1.45 |
E14M73 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.47 | 1.47 |
E14M74 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.49 | 1.49 |
E14M75 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.51 | 1.51 |
E14M76 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.53 | 1.53 |
E14M77 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.55 | 1.55 |
E14M78 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.57 | 1.57 |
E14M79 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.59 | 1.59 |
E14M80 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.61 | 1.61 |
E14M81 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.63 | 1.63 |
E14M82 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.65 | 1.65 |
E14M83 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.67 | 1.67 |
E14M84 | dσ/dΩ | e | p | π+n | 2.44 | 2.44 | 1.69 | 1.69 |
E14M85 | dσ/dΩ | e | p | π+n | 2.91 | 2.91 | 1.15 | 1.15 |
E14M86 | dσ/dΩ | e | p | π+n | 2.91 | 2.91 | 1.17 | 1.17 |
E14M87 | dσ/dΩ | e | p | π+n | 2.91 | 2.91 | 1.19 | 1.19 |
E14M88 | dσ/dΩ | e | p | π+n | 2.91 | 2.91 | 1.21 | 1.21 |
E14M89 | dσ/dΩ | e | p | π+n | 2.91 | 2.91 | 1.23 | 1.23 |
E14M90 | dσ/dΩ | e | p | π+n | 2.91 | 2.91 | 1.25 | 1.25 |
E14M91 | dσ/dΩ | e | p | π+n | 2.91 | 2.91 | 1.27 | 1.27 |
E14M92 | dσ/dΩ | e | p | π+n | 2.91 | 2.91 | 1.29 | 1.29 |
E14M93 | dσ/dΩ | e | p | π+n | 2.91 | 2.91 | 1.31 | 1.31 |
E14M94 | dσ/dΩ | e | p | π+n | 2.91 | 2.91 | 1.33 | 1.33 |
E14M95 | dσ/dΩ | e | p | π+n | 2.91 | 2.91 | 1.35 | 1.35 |
E14M96 | dσ/dΩ | e | p | π+n | 2.91 | 2.91 | 1.37 | 1.37 |
E14M97 | dσ/dΩ | e | p | π+n | 2.91 | 2.91 | 1.39 | 1.39 |
E14M98 | dσ/dΩ | e | p | π+n | 2.91 | 2.91 | 1.41 | 1.41 |
E14M99 | dσ/dΩ | e | p | π+n | 2.91 | 2.91 | 1.43 | 1.43 |
E14M100 | dσ/dΩ | e | p | π+n | 2.91 | 2.91 | 1.45 | 1.45 |