CLAS Physics Database

E93-006 CLAS experiment

Spokespersons
V. D. Burkert, M. Ripani
Year
2003
Abstract
The cross section for the reaction ep -> e' p pi+ pi- was measured in the resonance region for 1.4 < W < 2.1 GeV and 0.5 < Q2 < 1.5 GeV2/c2 using the CLAS detector at Jefferson Laboratory. The data show resonant structures not visible in previous experiments. The comparison of our data to a phenomenological prediction using available information on N* and Delta states shows an evident discrepancy. A better description of the data is obtained either by a sizable change of the properties of the P13(1720) resonance or by introducing a new baryon state, not reported in published analyses.
Publication
  1. M. Ripani, V. D. Burkert, V. I. Mokeev, M. Battaglieri, R. De Vita, E. Golovach, V. Tauti, and CLAS Collaboration Measurement of ep->e'p pi+pi- and Baryon Resonance Analysis // Phys. Rev. Let. 91, 022002 (2003)
Quantities
σ dσ/dM(π,p) dσ/dM(π+,p) dσ/dM(π+) dσ/d(−cos(θ(π))) dσ/d(−cos(θ(π+))) dσ/d(−cos(θ(p))) dσ/dφ(π) dσ/dφ(π+) dσ/dφ(p) dσ/dψ(π) dσ/dψ(π+) dσ/dψ(p)

Measurements

ID Quantity Beam Target Final state Q2min,
GeV2
Q2max,
GeV2
Wmin,
GeV
Wmax,
GeV
E1M1 dσ/dM(π+,p) e p π+πp 1.1 1.5 1.4 1.425
E1M2 dσ/dψ(π+) e p π+πp 1.1 1.5 1.4 1.425
E1M3 dσ/dφ(π+) e p π+πp 1.1 1.5 1.4 1.425
E1M4 dσ/dM(π,p) e p π+πp 1.1 1.5 1.4 1.425
E1M5 dσ/dψ(π) e p π+πp 1.1 1.5 1.4 1.425
E1M6 dσ/dφ(π) e p π+πp 1.1 1.5 1.4 1.425
E1M7 dσ/dφ(p) e p π+πp 1.1 1.5 1.4 1.425
E1M8 dσ/dψ(p) e p π+πp 1.1 1.5 1.4 1.425
E1M9 dσ/d(−cos(θ(π))) e p π+πp 1.1 1.5 1.4 1.425
E1M10 dσ/d(−cos(θ(p))) e p π+πp 1.1 1.5 1.4 1.425
E1M11 dσ/d(−cos(θ(π+))) e p π+πp 1.1 1.5 1.4 1.425
E1M12 dσ/d(−cos(θ(p))) e p π+πp 1.1 1.5 1.425 1.45
E1M13 dσ/dM(π,p) e p π+πp 1.1 1.5 1.425 1.45
E1M14 dσ/dM(π+,p) e p π+πp 1.1 1.5 1.425 1.45
E1M15 dσ/dψ(p) e p π+πp 1.1 1.5 1.425 1.45
E1M16 dσ/dφ(π) e p π+πp 1.1 1.5 1.425 1.45
E1M17 dσ/dφ(π+) e p π+πp 1.1 1.5 1.425 1.45
E1M18 dσ/dψ(π) e p π+πp 1.1 1.5 1.425 1.45
E1M19 dσ/d(−cos(θ(π))) e p π+πp 1.1 1.5 1.425 1.45
E1M20 dσ/dφ(p) e p π+πp 1.1 1.5 1.425 1.45
E1M21 dσ/dψ(π+) e p π+πp 1.1 1.5 1.425 1.45
E1M22 dσ/dM(π+) e p π+πp 1.1 1.5 1.425 1.45
E1M23 dσ/d(−cos(θ(π+))) e p π+πp 1.1 1.5 1.425 1.45
E1M24 dσ/dM(π+) e p π+πp 1.1 1.5 1.45 1.475
E1M25 dσ/d(−cos(θ(π))) e p π+πp 1.1 1.5 1.45 1.475
E1M26 dσ/dM(π,p) e p π+πp 1.1 1.5 1.45 1.475
E1M27 dσ/dM(π+,p) e p π+πp 1.1 1.5 1.45 1.475
E1M28 dσ/dφ(π+) e p π+πp 1.1 1.5 1.45 1.475
E1M29 dσ/dφ(π) e p π+πp 1.1 1.5 1.45 1.475
E1M30 dσ/dφ(p) e p π+πp 1.1 1.5 1.45 1.475
E1M31 dσ/dψ(p) e p π+πp 1.1 1.5 1.45 1.475
E1M32 dσ/d(−cos(θ(p))) e p π+πp 1.1 1.5 1.45 1.475
E1M33 dσ/dψ(π) e p π+πp 1.1 1.5 1.45 1.475
E1M34 dσ/dψ(π+) e p π+πp 1.1 1.5 1.45 1.475
E1M35 dσ/d(−cos(θ(π+))) e p π+πp 1.1 1.5 1.45 1.475
E1M36 dσ/dM(π,p) e p π+πp 1.1 1.5 1.475 1.5
E1M37 dσ/d(−cos(θ(π))) e p π+πp 1.1 1.5 1.475 1.5
E1M38 dσ/dM(π+,p) e p π+πp 1.1 1.5 1.475 1.5
E1M39 dσ/dφ(π) e p π+πp 1.1 1.5 1.475 1.5
E1M40 dσ/dφ(π+) e p π+πp 1.1 1.5 1.475 1.5
E1M41 dσ/dφ(p) e p π+πp 1.1 1.5 1.475 1.5
E1M42 dσ/dψ(π) e p π+πp 1.1 1.5 1.475 1.5
E1M43 dσ/dψ(π+) e p π+πp 1.1 1.5 1.475 1.5
E1M44 dσ/d(−cos(θ(π+))) e p π+πp 1.1 1.5 1.475 1.5
E1M45 dσ/dψ(p) e p π+πp 1.1 1.5 1.475 1.5
E1M46 dσ/d(−cos(θ(p))) e p π+πp 1.1 1.5 1.475 1.5
E1M47 dσ/dM(π+) e p π+πp 1.1 1.5 1.475 1.5
E1M48 dσ/dM(π+) e p π+πp 1.1 1.5 1.5 1.525
E1M49 dσ/d(−cos(θ(π))) e p π+πp 1.1 1.5 1.5 1.525
E1M50 dσ/dM(π,p) e p π+πp 1.1 1.5 1.5 1.525
E1M51 dσ/dM(π+,p) e p π+πp 1.1 1.5 1.5 1.525
E1M52 dσ/dφ(π) e p π+πp 1.1 1.5 1.5 1.525
E1M53 dσ/d(−cos(θ(p))) e p π+πp 1.1 1.5 1.5 1.525
E1M54 dσ/dφ(p) e p π+πp 1.1 1.5 1.5 1.525
E1M55 dσ/dψ(π) e p π+πp 1.1 1.5 1.5 1.525
E1M56 dσ/dψ(π+) e p π+πp 1.1 1.5 1.5 1.525
E1M57 dσ/dψ(p) e p π+πp 1.1 1.5 1.5 1.525
E1M58 dσ/d(−cos(θ(π+))) e p π+πp 1.1 1.5 1.5 1.525
E1M59 dσ/dφ(π+) e p π+πp 1.1 1.5 1.5 1.525
E1M60 dσ/dψ(π) e p π+πp 1.1 1.5 1.525 1.55
E1M61 dσ/dψ(π+) e p π+πp 1.1 1.5 1.525 1.55
E1M62 dσ/dM(π+) e p π+πp 1.1 1.5 1.525 1.55
E1M63 dσ/dψ(p) e p π+πp 1.1 1.5 1.525 1.55
E1M64 dσ/dM(π,p) e p π+πp 1.1 1.5 1.525 1.55
E1M65 dσ/dφ(π) e p π+πp 1.1 1.5 1.525 1.55
E1M66 dσ/dφ(π+) e p π+πp 1.1 1.5 1.525 1.55
E1M67 dσ/d(−cos(θ(π))) e p π+πp 1.1 1.5 1.525 1.55
E1M68 dσ/dφ(p) e p π+πp 1.1 1.5 1.525 1.55
E1M69 dσ/d(−cos(θ(π+))) e p π+πp 1.1 1.5 1.525 1.55
E1M70 dσ/dM(π+,p) e p π+πp 1.1 1.5 1.525 1.55
E1M71 dσ/d(−cos(θ(p))) e p π+πp 1.1 1.5 1.525 1.55
E1M72 dσ/dM(π,p) e p π+πp 1.1 1.5 1.55 1.575
E1M73 dσ/dψ(π) e p π+πp 1.1 1.5 1.55 1.575
E1M74 dσ/dM(π+,p) e p π+πp 1.1 1.5 1.55 1.575
E1M75 dσ/dφ(π) e p π+πp 1.1 1.5 1.55 1.575
E1M76 dσ/dφ(π+) e p π+πp 1.1 1.5 1.55 1.575
E1M77 dσ/dM(π+) e p π+πp 1.1 1.5 1.55 1.575
E1M78 dσ/dφ(p) e p π+πp 1.1 1.5 1.55 1.575
E1M79 dσ/dψ(π+) e p π+πp 1.1 1.5 1.55 1.575
E1M80 dσ/dψ(p) e p π+πp 1.1 1.5 1.55 1.575
E1M81 dσ/d(−cos(θ(π))) e p π+πp 1.1 1.5 1.55 1.575
E1M82 dσ/d(−cos(θ(p))) e p π+πp 1.1 1.5 1.55 1.575
E1M83 dσ/d(−cos(θ(π+))) e p π+πp 1.1 1.5 1.55 1.575
E1M84 dσ/dM(π,p) e p π+πp 1.1 1.5 1.575 1.6
E1M85 dσ/dψ(π) e p π+πp 1.1 1.5 1.575 1.6
E1M86 dσ/dM(π+,p) e p π+πp 1.1 1.5 1.575 1.6
E1M87 dσ/dφ(π) e p π+πp 1.1 1.5 1.575 1.6
E1M88 dσ/dφ(π+) e p π+πp 1.1 1.5 1.575 1.6
E1M89 dσ/dM(π+) e p π+πp 1.1 1.5 1.575 1.6
E1M90 dσ/dφ(p) e p π+πp 1.1 1.5 1.575 1.6
E1M91 dσ/dψ(π+) e p π+πp 1.1 1.5 1.575 1.6
E1M92 dσ/dψ(p) e p π+πp 1.1 1.5 1.575 1.6
E1M93 dσ/d(−cos(θ(π))) e p π+πp 1.1 1.5 1.575 1.6
E1M94 dσ/d(−cos(θ(p))) e p π+πp 1.1 1.5 1.575 1.6
E1M95 dσ/d(−cos(θ(π+))) e p π+πp 1.1 1.5 1.575 1.6
E1M96 dσ/dM(π+) e p π+πp 1.1 1.5 1.6 1.625
E1M97 dσ/dψ(p) e p π+πp 1.1 1.5 1.6 1.625
E1M98 dσ/d(−cos(θ(π))) e p π+πp 1.1 1.5 1.6 1.625
E1M99 dσ/dM(π,p) e p π+πp 1.1 1.5 1.6 1.625
E1M100 dσ/dM(π+,p) e p π+πp 1.1 1.5 1.6 1.625