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Testing Λ (1405) with K-mesic atoms. S.Wycech IPJ, Warsaw The purpose Λ (1405) is the dorway and the mechanism to bind the „K-mesic nuclei”. Two approaches to Λ (1405). Phenomenology K – matrix fitted to data + dispersion relations Extrapolation below KN , E ~ 1405 MeV
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Testing Λ(1405) with K-mesic atoms S.Wycech IPJ, Warsaw The purpose Λ(1405) is the dorway and the mechanism to bind the „K-mesic nuclei” Wycech, Meson- 2010
Two approaches to Λ(1405) • Phenomenology K – matrix fitted to data + dispersion relations Extrapolation below KN , E ~ 1405 MeV PDG, R.Dalitz, A.Martin.. many others since 1970 ▪ Chiral models SU(3) symmetric driving force , pole in Σπ, pole in KN plane , E ~ 1420 MeV W.Weise, E.Oset .. others since 2000 Wycech, Meson- 2010
Experimental check K N Σπ below threshold in final states not conclusive provides amplitude a(K N,Σπ) no a(K N,KN) Wycech, Meson- 2010
Two new (?) suggestions to extract KN amplitudes from • Upper atomic levels 2) Atomic nuclear radiative transitions Wycech, Meson- 2010
„upper levels „ s p d …. n= 3 n= 2 „ upper ” n= 1 „ lower „ Wycech, Meson- 2010
Upper levels „do not fit „ E. Friedman , A.Gal Im a= 0.37 fm upper levels Im a= 0.94 fm lower levels Г ~ Im a (KN, E = - EBINDING - ERECOIL ) 5 - 25 % accurate in upper levels impulse approx. not valid in lower levels Wycech, Meson- 2010
Nucleon levels „seen” in atoms V(r) radial distance lower upper levels Wycech, Meson- 2010
Parallel case, antiprotonic atoms Nuclear regions studied in atomic levels loweruppercold capture ↓ ↓ ↓ ρ(r) Wycech, Meson- 2010
P-bar Nsubthreshold energies involved in p-baratoms -40 -20 0 MeV • P • D T He 4 Wycech, Meson- 2010
Im a(E) extracted from light antiprotonic atoms - PS 207 data Paris model Wycech, Meson- 2010
Im aKN(E) extracted from upper widths Wycech, Meson- 2010
Im a(KN) extracted from upper widths Wycech, Meson- 2010
Favorite situation for studying Г(upper): one or few nucleon orbitals perfect P,D,He, very good Li, Be, C, N,O, resonable in almost all atoms Wycech, Meson- 2010
K-neutron dominated widths Upper widths due mostly to Kn , S + P wave Pb Im a (K – n) Apparently dominated by Σ(1385) Wycech, Meson- 2010
Another possibility to study sub-threshold elastic KN or K-nucleus amplitude Wycech, Meson- 2010
K-hydrogen Λ(1405 ) + γ Kaons lost in cascade Kaonic Hydrogen ~ 95% lost How many go to Λ(1405 ) + γ ? Wycech, Meson- 2010
Old BNL experiment K – p Σ(1190) γ Found on the level of 1/1000 D.A.Whitehouse ..PRL.63(89)1352; K.D.Larsen.. Phys.Rev D47(93)799 K – p Λ(1405)γ Is it feasible ? What is the line shape ? Wycech, Meson- 2010
High energy photons from K- p atom Wycech, Meson- 2010
Gamma rays to Λ(1405)5 10-3 of captures from ( n P) levels s p d n= 3 n= 2 n= 1 Λ(1405) Wycech, Meson- 2010
Occupation and capture from all (n,P) states estimated captures from n P states in gas targets ~ few % of stopped K mesons Total chance for γ transition ~ 0.001-0.0001 per stopped kaon Wycech, Meson- 2010
Kaonic deuterium atom KNN Deep state ~100 MeV ( FINUDA, DISTO) Very small chance Weakly bound or virtual state ~ 47 MeV P+Σ(1385) sw Phys. Rev C 79 Good chance Wycech, Meson- 2010
Line shape Г = ∫ dk S(k) S(k) = Im TKN,KN (Eo–k) k GKN(k) Wycech, Meson- 2010
LINE SHAPE resonance●propagator●phase space Σπ T GKN γ p K- Wycech, Meson- 2010
Summary Upper widths in K atoms may determine Im TKN,KN(M K + MN – E ) for E = 0 - 40 MeV K -Atom K-Nuclear + γ may give elastic Im TKNUCLEUS(M K + MN – E ) Experiments are difficult Wycech, Meson- 2010
Upper levels –suggestions Interesting measurements • He (2p ) • Be , C , repetition • Sn 112,116,118,124 – different proton bindings Pb 208 Kn parameters in addition to D Wycech, Meson- 2010
