1 / 23

Exotic states in S=1 N  K system and low lying ½+ S=-1 resonances

Fri, Sept.4 2009. Exotic states in S=1 N  K system and low lying ½+ S=-1 resonances. Kanchan Khemchandani , Departamento de Fisica , Universidad de Coimbra, Portugal. 19th International IUPAP Conference on Few-Body Problems in Physics 31.08 - 05.09.2009 - University of Bonn / Germany.

zofia
Télécharger la présentation

Exotic states in S=1 N  K system and low lying ½+ S=-1 resonances

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. Fri, Sept.4 2009 Exotic states in S=1 NK system and low lying ½+ S=-1 resonances • KanchanKhemchandani, • Departamento de Fisica, Universidad de Coimbra, Portugal. 19th International IUPAP Conference on Few-Body Problems in Physics 31.08 - 05.09.2009 - University of Bonn / Germany

  2. Collaborators:Alberto Martinez Torres and Eulogio OsetIFIC-Univ. de Valencia, Spain

  3. Why study the KN system? • A peak K+n invariant mass in the γ n → K+K−n reaction at the Spring8/Osaka  pentaquark • The picture is not clear yet. • KN interaction chiral dynamics repulsive • suggestions  KN bound state • Some investigations have already been done  results not promising • Our study of the KN (S=-1) system  several resonances  revisit KN and make a conclusive study (T. Nakano [LEPS Collaboration], Talk at the PANIC 2002 (Oct. 3, 2002, Osaka); T. Nakano et al., Phys. Rev. Lett. 91, 012002 (2003)) (P. Bicudo, G. M. Marques, Phys. Rev. D69, 011503, 2004; F. J. Llanes-Estrada, E. Oset and V. Mateu, Phys. Rev. C 69, 055203 (2004).)

  4. The KN system. • We started studying the system: • All the interactions are in S-wave . • There are some S=-1, 1/2+ baryonic states in the energy region 1500-1800 MeV whose properties, as spin-parity, are not well understood. 1 2 3 1D. Jido, J. A. Oller, E. Oset, A. Ramos, U. G. Meissner, Nucl. Phys. A 725 (2003) 181-200. 2 T. Inoue, E. Oset, M. J. Vicente Vacas, Phys. Rev. C 65 035204 . 3 J. A. Oller, E. Oset, J. R. Peláez, Phys. Rev. D 59 074001 (199).

  5. 137+1405 =1542 MeV Seems to show up in  production

  6. Some of them seem to remain unexplained in terms of two-body dynamics e.g., a detailed study of the K-p  ppL reaction by Roca et al.4 explains the bulk of the data5, but fails to explain a bump in the L(1600) region. L(1600) 4 L. Roca, S. Sarkar, V. K. Magas and E. Oset, Phys. Rev. C 73, 045208 (2006). 5 S. Prakhov et al., Phys. Rev. C 69, 042202 (2004).

  7. The Formalism • We solve the Faddeev equations • The matrices contain all the possible diagrams where the last two successive interactions are ti and tj • And they satisfy the equations:

  8. In th e Coupled channel approach ( pseudo-scalar mesons of the SU(3) octet + baryons of the 1/2+ octet) → couple to S=-1 ↓ add 

  9. The Formalism • We solve the Faddeev equations • The matrices contain all the possible diagrams where the last two successive interactions are ti and tj • And they satisfy the equations:

  10. ´

  11. Chiral amplitudes

  12. = 0

  13. where

  14. We extend the procedure for the rest of diagrams involving more than three t-matrices • Variables of the eqn: s, s23

  15. Results (S= -1 system , I=1) Σ(1660) P11 [ I(JP)=1(1/2+) ] ***

  16. Σ(1620) S11 [ I(JP)=??] ** Σ(1660) P11 [ I(JP)=1(1/2+) ] *** R. Armenteros et al. Nucl. Phys. B 8, 183 (1968). B. R. Martin et al, Nucl. Phys. B 127, 349 (1977).

  17. Results (S= -1 sytem ,I =0) Λ(1810) P01 [ I(JP)=0(1/2+) ] *** 1750 to 1850 (~ 1810) OUR ESTIMATE

  18. Λ(1600) P01 [ I(JP)=0(1/2+) ] *** 1560 to 1700 (~ 1600) OUR ESTIMATE There are quite possibly two P01 states in this region. 1568 - i 60/2 MeV

  19. The KN system. • We study KNsystem using the same formalism. • We take p 0K0, n 0K+, p −K+, n +K0 as coupled channels. • For which, we take K+0, K0+, K+,  0p,  +n, ηp  charge +1. K+  −, K0  0, K0 ,  −p,  0n, ηn  charge 0. N interaction  +K0,  0K+ for K  charge +1. −K+, 0K0 for  K  charge 0. K interaction K0p, K+n  charge +1 K0n  charge 0 and K+p  charge +2. KN interaction

  20. We find no peak around 1540 MeV. • We find a bump at ~ 1720 MeV with 200 MeV of FWHM in isospin 0 amplitude  with K in isospin 0 configuration and with K mass ~ 800 MeV • No peak in other isospin cases. A bump also in the time delay analysis of KN data N. G. Kelkar et. al. JPG 29, 1001 (2003) K.P. Khemchandani, A. Martinez Torres, E. Oset Phys. Lett. B (2009)

  21. Summary Jp = ?? Ref: AMartínez Torres, K. P. Khemchandani, E. Oset , Phys. Rev. C77:042203,2008; Eur. Phys. J. A35: 295-297,2008

  22. S= -1 sector → four Σ’s and two Λ’s resonances (all the 1/2+ Σ and Λ states in the energy region 1500-1870. ) • S=+1 → a bump around 1720 MeV with ~ 200 MeV of width, No resonance around 1540 MeV.

More Related