1 / 19

KN phase shifts in chiral quark model

KN phase shifts in chiral quark model. F. Huang, Z.Y. Zhang, Y.W. Yu (Institute of High Energy Physics, Beijing, China). Outline. Motivations Formulation The model Determination of parameters Results  discussions Summary. Motivations. To extend our model to study BM interactions

braden
Download Presentation

KN phase shifts in chiral quark model

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. KN phase shifts in chiral quark model F. Huang, Z.Y. Zhang, Y.W. Yu (Institute of High Energy Physics, Beijing, China)

  2. Outline • Motivations • Formulation • The model • Determination of parameters • Results  discussions • Summary

  3. Motivations • To extend our model to study BM interactions • NPQCD effect is important; QCD-inspired models are still needed • Our model works well for NN and NY • To extend our model to study BM interactions; Start with KN in which annihilation is simple • To get a better understanding of KN interaction • Most of previous works based on CQM failed to accurately reproduce the KN phase shifts • Can we reproduce KN phase shifts in our model?

  4. Formulation (1)  the model The Hamiltonian of KN system Generalize the idea of SU(2) σ model to SU(3)f case Clearly, HIch is invariant under the infinitesimal chiral SU(3)LSU(3)R transformation.

  5. From HIch, the SU(3) chiral-field-induced quark-quark potentials can be derived

  6. The exchange diagrams forqq The annihilation diagrams forqq For KN, there are alsoqq interactions For KN system,qq can only annihilate into kaon Ck is adjusted to fit the mass of kaon

  7. Formulation (2)  parameters fitting • Input: bu=0.5 fm, mu=313 MeV, ms=470 MeV • The chiral field coupling constant • Mesons’ masses: experimental values • Except mσ (adjustable parameter), mσ=675 MeV • Λ-1=0.18 fm, close to chiral symmetry breaking scale • gu and gs, determined by mΔ-mN and mΣ-mΛ • Parameters of Vconf, fitted by baryons’ masses and their stability conditions

  8. About the mixing angle We consider the mixing between the flavor singlet and octet mesons PS= –23 The mixing of scalar meson is still an open problem ⅠS≈ 35 ⅡS= –18 Y.B. Dai, Y.L. Wu, hep-ph/0304075

  9. Model parameters mσ׳=980 MeV, m=980 MeV mε=980 MeV, mσ=675 MeV m=138MeV, m=495 MeV m=549MeV, mη׳=957 MeV Λ=1100 MeV The masses of baryons

  10. Results  discussions • RGM calculation • Conventional notation LI 2J

  11. About the mixing of σ0 and σ8 We took two possible values of S ⅠS≈ 35 ⅡS= –18 The attraction of σ is reduced in both of these two cases

  12. Influence of the annihilation The numerical phase shifts scarcely have changes whenwe omit the annihilation part entirely. The annihilation diagrams forqq The annihilation part coming form S-channel acts in the very short range, so it plays a non-significant role in KN scattering process.

  13. Comparing with recent RGM study S. Lemaire et al, NPA 714 (2003) 265 gluon++s+confinement, RGM calculation

  14. Summary • The chiral SU(3) quark model is extended to includeq • KN scattering process is studied using RGM • Our results achieve a considerable improvement on theoretical phase shifts comparing with others’ works A reasonable interaction between K and N can be obtained from the chiral SU(3) quark model when the mixing of σ0 and σ8 is considered and mσ is taken to be 675 MeV

  15. The end Thank you for your patience

More Related