arXiv subjects

Jure Zupan

Publications and source records attributed to Jure Zupan.

149 records · Page 9Linked to original sources

arXiv2003

Final State Interactions in the Ds+ --> omega pi+ and Ds+ --> rho0 pi+ Decays

We investigate the decay mechanisms in the Ds+ --> omega pi+ and Ds+ --> rho0 pi+ transitions. The naive factorization ansatz predicts vanishing amplitude for the Ds+ --> omega pi+ decay, while the Ds+ --> rho0 pi+ decay amplitude does have an annihilation contribution also in this limit. Both decays can proceed through intermediate states of hidden strangeness, e.g. K, K*, which we estimate in this paper. These contributions can explain the experimental value for the Ds+ --> omega pi+ decay rate, which no longer can be viewed as a clean signature of the annihilation decay of Ds+. The combination of the π(1300) pole dominated annihilation contribution and the internal K, K* exchange can saturate present experimental upper bound on Ds+ --> rho0 pi+ decay rate, which is therefore expected to be within the experimental reach. Finally, the proposed mechanism of hidden strangeness FSI constitutes only a small correction to the Cabibbo allowed decay rates Ds--> K K*, phi pi, which are well described already in the factorization approximation.

hep-ph↗

arXiv2003

Determination of the angle gamma using multibody D decays in B^+- -> D K^+-

We describe a method for determining gamma using B^+- -> D K^+- decays followed by a multibody D decay. In the talk we focus on K_S pi^- pi^+ final state, but other modes such as D -> K_S K^- K^+ and D -> K_S pi^- pi^+ pi^0 can also be used. The main advantages of the method are that it uses only Cabibbo allowed D decays, and that large strong phases are expected due to the presence of resonances. Since no knowledge about the resonance structure is needed, gamma can be extracted without any hadronic uncertainty.

hep-ph↗

arXiv2003

Determining $γ$ using $B^\pm \to D K^\pm$ with multibody D decays

We propose a method for determining $γ$ using $B^\pm\to D K^\pm$ decays followed by a multibody $D$ decay, such as $D \to K_S π^-π^+$, $D \to K_S K^-K^+$ and $D \to K_S π^-π^+π^0$. The main advantages of the method is that it uses only Cabibbo allowed $D$ decays, and that large strong phases are expected due to the presence of resonances. Since no knowledge about the resonance structure is needed, $γ$ can be extracted without any hadronic uncertainty.

hep-ph↗

arXiv2003

B-->pi and B-->K transitions in standard and quenched chiral perturbation theory

We study the effects of chiral logs on the heavy-->light pseudoscalar meson transition form factors by using standard and quenched chiral perturbation theory combined with the static heavy quark limit. The resulting expressions are used to indicate the size of uncertainties due to the use of the quenched approximation in the current lattice studies. They may also be used to assess the size of systematic uncertainties induced by missing chiral log terms in extrapolating toward the physical pion mass. We also provide the coefficient multiplying the quenched chiral log, which may be useful if the quenched lattice studies are performed with very light mesons.

hep-lat↗

arXiv2002

Effects of initial axion production and photon--axion oscillation on type Ia supernova dimming

Recently, Csaki, Kaloper and Terning (CKT) suggested that axion-photon oscillation in the intergalactic medium can explain the observed dimming of distant type Ia supernovae. This mechanism works only if the initial axion flux is much smaller than the initial photon flux. We study several mechanisms for such initial axion production. The direct axion production in the supernovae, the photon-axion oscillation in the magnetic field of supernovae and in the magnetic field of their host galaxies are addressed. We find it likely that the initial axion flux is very small and therefore does not pose a problem to the CKT mechanism.

hep-ph↗