Multi-Strange and Charmed Antihyperon-Hyperon Physics for PANDA
2012 (English)Doctoral thesis, monograph (Other academic)
The prospects of studying multi-strange and charmed antihyperon-hyperon physics and CP violation in hyperon decays in the upcoming PANDA experiment at FAIR, Germany, have been studied in this thesis.
The angular dependence on polarisation parameters in the decay of the spin 3/2 Omega hyperon was calculated using the density matrix formalism. Expressions for the angular distributions in the Ω -> ΛK and the subsequent Λ -> pπ decays were derived.
Simulations were performed for the pbar p -> Ξ+ Ξ-, pbar p -> Ω+Ω- and pbar p -> Λc-Λc+ reactions. Special attention was given to the reconstruction of spin variables. It is shown that PANDA will register tens of events per second for the pbar p -> Ξ+Ξ- reaction. This should be compared to the previously existing data of a handfull of events. For the other two reactions the event rates will be lower, but still reasonably high. This will be the first measurements of these reactions. It is shown that spin variables can be reconstructed in all three reactions for all production angles of the hyperons. Simulations concerning the possibility to measure CP violation parameters in hyperon decays were also made for the reactions pbar p- > Λbar Λ and pbar p -> Ξ+Ξ-. It was found that false signals from detector asymmetries disappears if no particle identification criterium is used and the analysis is restricted to events were the hyperon decays occur close to the beam axis.
The effect of the magnetic field in the PANDA detector on the measurement of hyperon spin variables was investigated for the case of pbar p -> Λbar Λ. The effect was observed to be small for polarisation and negligible for spin correlations.
Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2012. , 154 p.
Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1104-2516 ; 101
PANDA, FAIR, antiproton, hyperon, strangeness, charm, polarisation, spin correlation, CP violation
Research subject Nuclear Physics
IdentifiersURN: urn:nbn:se:uu:diva-182450ISBN: 978-91-554-8497-2OAI: oai:DiVA.org:uu-182450DiVA: diva2:559868
2012-11-23, Häggsalen, Ångströmlaboratoriet, Lägerhyddsvägen 1, Uppsala, 10:15 (English)