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Register a new userDetermining the dominant partial wave contributions from angular distributions of single- and double-polarization observables in pseudoscalar meson photoproduction
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Added by
Yannick Wunderlich PhD
Publication date
2016
fields
Physics
and research's language is
English
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This work presents a simple method to determine the significant partial wave contributions to experimentally determined observables in pseudoscalar meson photoproduction. First, fits to angular distributions are presented and the maximum orbital angular momentum $text{L}_{mathrm{max}}$ needed to achieve a good fit is determined. Then, recent polarization measurements for $gamma p rightarrow pi^{0} p$ from ELSA, GRAAL, JLab and MAMI are investigated according to the proposed method. This method allows us to project high-spin partial wave contributions to any observable as long as the measurement has the necessary statistical accuracy. We show, that high precision and large angular coverage in the polarization data are needed in order to be sensitive to high-spin resonance-states and thereby also for the finding of small resonance contributions. This task can be achieved via interference of these resonances with the well-known states. For the channel $gamma p rightarrow pi^{0} p$, those are the $N(1680)frac{5}{2}^{+}$ and $Delta(1950)frac{7}{2}^{+}$, contributing to the $F$-waves.
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