Missing Resonances
نویسندگان
چکیده
منابع مشابه
The search for missing baryon resonances
Experiments with electromagnetic probes are promising to search for baryon resonances that have been predicted by quark models but have not yet been observed. Data sets from different experiments show interesting resonance structures possibly due to so far unknow states. This might indicate that at least some of the missing baryon resonances start to show up. Introduction At medium energies, ou...
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New kaon photoproduction data on a proton, γ + p → K + Λ, are analyzed using a multipole approach. The background terms are given in terms of gauge invariant, crossing symmetric, Born diagrams with hadronic form factors, while the resonances are parameterized using Breit-Wigner forms. Preliminary results suggest a number of new resonances, as predicted by many quark model studies. A comparison ...
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Like any composite system the nucleon can be excited into a number of resonant or compound states. However, due to the nonperturbative nature of QCD at nucleon resonance energies no rigorous understanding of N resonances on the basis of QCD has emerged. Lattice QCD has only recently begun to contribute to this field. In a recent study 1 the excitation energies of 1/2 and 3/2 baryon resonances a...
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In this work, an improved quark model approach to the ω meson photoproduction with an effective Lagrangian is reported. The t-channel natural parity exchange is consistently taken into account through the Pomeron exchange, while the unnatural parity exchange is described by the π 0 exchange. It shows that with very limited number of parameters, all the available experimental data in the low ene...
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T he notion that the distribution of firm size in poor countries is characterized by a bimodal distribution with a “missing middle” is a widely accepted fact in development economics (for example, see Krueger 2013). The idea of the missing middle is that there are a large number of small firms, some large firms, but very few medium-sized firms. The purported fact about the missing middle is cit...
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ژورنال
عنوان ژورنال: Journal of Nuclear Science and Technology
سال: 1967
ISSN: 0022-3131,1881-1248
DOI: 10.1080/18811248.1967.9732754