Baryon spectroscopy: Recent results from the Crystal Barrel/TAPS experiment at ELSA

Journal Article · Thu Aug 05 00:00:00 EDT 2010 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.3483315· OSTI ID:21426376

Thoma, U ^[1]

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1. Helmholtz-Institut fuer Strahlen- und Kernphysik, Universitaet Bonn (Germany)

To understand the spectrum and the properties of baryon resonances, the CBELSA/TAPS experiment at ELSA investigates the photoproduction of single- and multi-meson final states off the nucleon. In the latter final states baryon cascades via Dp and Dh and also via higher mass baryon resonances are clearly observed. A partial wave analysis based on single and double meson photoproduction data as well as data from other reactions allows a first determination of resonance properties including partial decay widths of various N* and {Delta}* states. Those include also the decays into the different p{pi}{sup 0{pi}0} and p{pi}{sup 0{eta}} decay channels resulting partly in unexpected results. Recently not only single but also double polarisation experiments have been performed, which are absolutelly necessary to resolve ambiguities in the partial wave analyses (PWA) used to extract the resonances from the data; without the measurement of polarisation observables a model-independent PWA will not be possible. Polarisation observables have been investigated using linearly, circularly polarized or unpolarized photons impinging on an longitudinally polarized or unpolarized target. Given the angular coverage of the Crystal-Barrel/TAPS experiment this data cover almost the full angular range and phase space. This data will provide key information for the partial wave analyses and brings us one step closer towards the needed complete experiment.

• OSTI ID: 21426376
• Journal Information: AIP Conference Proceedings, Vol. 1257, Issue 1; Conference: HADRON 2009: 13. international conference on hadron spectroscopy, Tallahassee, FL (United States), 29 Nov - 4 Dec 2009; Other Information: DOI: 10.1063/1.3483315; (c) 2010 American Institute of Physics; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BARYON SPECTROSCOPY
DELTA BARYONS
ETA MESONS
MULTIPARTICLE SPECTROMETERS
NUCLEONS
PARTIAL WAVES
PARTICLE DECAY
PARTICLE IDENTIFICATION
PHASE SPACE
PHOTON-NUCLEON INTERACTIONS
PHOTONS
PHOTOPRODUCTION
POLARIZATION
QUANTUM CHROMODYNAMICS
QUARK MODEL
RESONANCE PARTICLES
BARYONS
BASIC INTERACTIONS
BOSONS
COMPOSITE MODELS
DECAY
ELECTROMAGNETIC INTERACTIONS
ELEMENTARY PARTICLES
FERMIONS
FIELD THEORIES
HADRONS
INTERACTIONS
MASSLESS PARTICLES
MATHEMATICAL MODELS
MATHEMATICAL SPACE
MEASURING INSTRUMENTS
MESONS
N*BARYONS
PARTICLE INTERACTIONS
PARTICLE MODELS
PARTICLE PRODUCTION
PHOTON-BARYON INTERACTIONS
PHOTON-HADRON INTERACTIONS
PSEUDOSCALAR MESONS
QUANTUM FIELD THEORY
SPACE
SPECTROMETERS
SPECTROSCOPY