The International Search of Deeply Bound Kaonic States
The International Search of Deeply Bound Kaonic States Laura Fabbietti S. Wycech, Nucl Phys. A 450 (1986) 399 c Underlaying Theory Experimental Results and some Interpretations New Experiments
The (1405) Case Assumption: (1405) -> T=0, K-N state How many poles? Bare KN potential that reproduces: 1. K-N scattering lengths 2. Binding energies and width of kaonic atom 3. Binding Energy and Width of (1405) T. Yamazaki and Y. Akaishi, PLB (2002) Im f Me. V =50 Me. V p p p Kaon p 10 Me. V BE, M=1420 Me. V/c 2 M=1390 Me. V/c 2, 50 Me. V Later. . Dote and W. Weise hyp 2006 Proc. , nucl-th/0701050 N. V. Shevchenko et al. , Phys. Rev. Lett. 98, 082301 (2007) Me. V Weise et al. ar. Xiv: nucl-th: 0712. 1612 =100 Me. V Can we measure (1405)?
Experimental Searches for KC • (stopped K, N) reaction – KEK E 471/E 549 • 4 He(K+ stop, n)S (3140) ppn. K-? (BE=169 Me. V) • 4 He(K 0 stop, p)S (3115) ppn. K-? (BE=193 Me. V) – FINUDA/DA NE • Li/C(K-stop, +p)pp. K • (K, N) reaction – BNL-AGS E 930 • 16 O(K-, n)15 OK • Al+Al, Ni+Ni - FOPI ( p, d) • p+4 He - Obelix ( d) • Missing-mass spectroscopy – Example: • Invariant-mass spectroscopy – Example:
Experimental result E 471@ KEK 4 He(stopped K-, n) ppn. K-
ppn. KIwasaki et al. nucl-ex/0310018 Observed BK ~ 173 Me. V GK ~ 25 Me. V ~ 3137 Me. V/c 2 Predicted(Akaishi 2002) BKth ~127 Me. V M including the relativistic correction GKth ~ 30 Me. V BKexp - BKth ~ 46 Me. V pnn. KT. Suzuki et al. Phys. Lett B 597, 263 (2004) Observed BK ~ 194 Me. V GK ~ M 21 Me. V ~ 3117 Me. V/c 2 M. Sato et al nucl-ex/0708. 2968 v 1
FINUDA @ DAΦNE e+-e- collider -> f ->K+ KEnergy Resolution for : 1 Me. V (FWHM) K-Li pp. K p
pp. K- in p and back-to-back correlations Agnello et al. PRL 94(2005)212303
Proton Spectra with FINUDA Agnello et al. Nucl. Phys. A 775: 35 -50, 2006 Momentum distribution for protons 6 Li 12 C P ->275 Me. V/c + cos p Impact parameter from Montecarlo from Experimental Data (6 Li) K-+d--> -+p -->n+ p With d at rest. proton pion But. . . np have 250 Me. V/c --> p cannnot be monoenergetic!!! Yamazaki et al. nucl-ex/0609041 v 2
Finuda d for 6 Li -target M. Agnello et al. Phys. Lett. B 654: 80 -86, 2007. d – invariant mass analysis M = 3251 ± 6 Me. V = 37 ± 14 Me. V Y = (4. 4 ± 1. 4). 10 -3 / stopped KStatistical significance: 3. 9 No structure visible for 12 C – target! (claim: FSI destroys signal)
Another (ppn. K-) – claim T. Bressani et al. Nucl. Phys. A 789: 222 -242, 2007. OBELIX – Experiment at LEAR Significance: 2. 6 (3. 1) ( d) invariant mass Peak: 3190 ± 15 Me. V Width: < 60 Me. V
Search for pp. K- in HIC (FOPI) Rapidity distribution p – invariant mass Ni+Ni Al+Al FINUDA midrapidity Excess observed in Ni+Ni and Al+Al with statistical significance of ~ 5. Yield located in spectator/fireball interface region (like non-strange clusters). Peak position in variance with FINUDA result. Interpretation unclear: SN – FSI, bound state (H 1 +), partial inv. mass of heavier state (e. g. 4 He).
Summary for Strange Di/Tri-baryons d (ppn. K-) M (Me. V) P/ P/ IN Sign (s) HI: Al+Al - - - HI: Ni+Ni 3149 ± 15 100 ± 49 1. 3. 10 -2 1. 0. 10 -5 4. 9 FINUDA Phys. Lett. B 654: 80 -86, 2007 K- stopped on 6 Li 3251 ± 6 37 ± 14 4. 4. 10 -3 3. 9 KEK E 549 Iwasaki et al. nucl-ex/0310018 K- stopped in LHe - - Obelix Nucl. Phys. A 789: 222 -242, 2007. p stopped in 4 He 3190 ± 15 < 60. >0. 4. 10 -4 2. 6 FOPI - p (pp. K-) FOPI M (Me. V) P/ HI: Al+Al 2120 ± 10 59 ± 12 1. 7. 10 -2 5. 0 HI: Ni+Ni 2140 ± 10 59 ± 19 2. 2. 10 -2 5. 4 2255 ± 9 67 ± 14 3 -4. 10 -2 2209 ± 5 < 24. 4 FINUDA K- stopped on Obelix p stopped in 4 He PRL 94(2005)212303 12 C, 6, 7 Li P/ IN Sign (s) 1. . 10 -3 ? (10) >1. 4. 10 -4 3. 7
Results from the DEAR Experiment (Kaonic hydrogen) Courtesy of W. Weise K-p Scattering Length • Inhaltsfolie
Scattering Data & Kaonic Atoms (1405) cannot be described using Chiral Perturbation Theory. Chiral SU(3) dynamics with Coupled channels (KN<->S ) Scattering data
‚Data Base‘ for the Effective Potentials Need for ‚Yes‘ or ‚No‘ experiment for the pp. K- system (FOPI. . ) Need for high statistics Kaonic Atom Data (SIDDHARTA) Need for an accurate measurement of the S channel (FOPI. . )
(1405) @ANKE I. Zychor et al nucl-exp/0705. 1039 v 2 p+p(Ep=2. 8 Ge. V/c)-->p. K+Y 0 (1385)--> but NO (1405)--> FWHM( )=5 Me. V/c 2 Phase space background L= 70 pb-1 Disto : Tot( (1405)@ 2. 83 Ge. V =12 b extrapolated @ 3. 5 Ge. V = 40 b
pp. K- production in p+p reactions T. Yamazaki et T. Akahishi, nucl-th/0604049 (2006) * (1405) p+p ' (1405)‘+p+K+ pp. K-+K+ p+p: short range interaction (r<0. 3 fm) R( *-p)~1. 45 fm assisted by a large momentum transfer +p - + p Missing Mass & Invariant Mass + +p p+p ‚ (1405)‘+p+K+ 0 +p+K+ n + - p 0 - 4 charge particles + evt hyp.
FOPI Setup First Level Trigger (Ch. Mul) + trigger Helitron CDC PLAWA CDC Barrel/RPC siΛVio A p K+ 3 cm siΛVio A siΛVio B p p siΛVio B 10 cm silicon Vertexing and identification online Trigger: Online Vergleich zwischen Multiplizität siΛVio A und Multiplizität siΛVio B.
K+ and identification P (Ge. V/c) Courtesy of N. Herrmann Data from p+C@ 3. 5 Ge. V Sep 07 Ni+Ni@1. 94 AGe. V t d p K+ K- + - v (cm/ns) K+ - identification by momentum – TOF analysis up to plab=1 Ge. V/c Time resolution estimate from fast pions: t(RPC)<80 ps : Sig = 194 S/B = 3. 7 FWHM= 11 Me. V P = 4. 6*10 -4
Expected Signal for pp. K Direct K+ PID 27°<q. K+<45°, 0<p. K+<1 Ge. V/c p+p +K++p Indirect K+ PID (evt hypothesis) 7°<q. K+<33° S/(S+B) = 0. 03 for s= 5 S=1000 (s pp. K-)=1 b) Needed beam time (5 s =72 shift Granted beam time in Apr 07 = 42 shifts +12 p. s.
First Hint in HADES Apr 07 p+p@3. 5 Ge. V, 1/75 of the total statistics: 75. 000 -K+ events.
Comparison HADES vs FOPI Energy Geometrical Acceptance for pp. KMass Resolution and Efficiency Statistik 3 Ge. V (p+p) 18% HADES 3. 5 Ge. V (p+p) 3% M 2 K (Ge. V 2) FOPI : Mass= 5 Me. V/c 2 <Eff>= 10% ( K+: Mass=15. 5 Me. V/c 2 S/B = 10 (up to 1000 Me. V/c) 2 E=3. 5 Ge. V : Mass=2. 5 Me. V/c <Eff>= 10% K+: Mass=18. 5 Me. V/c 2 S/B=? (up to 600 Me. V/c) 1. 2 • 108 M 3 evt • 10 ( trigger) To be taken in 2009 1. 12 • 109 M 3 evt Already on tape Number calculated for 42 shifts and a beam intensity of 105 p/sec ( including extraction time and duty cycle) 4. 0 3. 5 E=3 Ge. V Thanks to the MDC 2. 5 4. 5 5. 0 5. 5 De/dx 3. 0 M 2 p 6. 0 6. 5 (Ge. V 2)
KLOE & AMADEUS KLOE --> AMADEUS Cryogenic target Inner Tracker Kaon trigger
Analysis of the KLOE Data For the kaonic clusters a total luminosity of L=3. 5/4 fb-1 is needed. Luminosity upgrade@ �Da ne
Future Measurement and Analysis New Data FINUDA@DA NE (K-, N) HADES@GSI (p, p) New Experiments FOPI@GSI (p, p) 2009 HADES@GSI (p, N) E 15@J-PARC (K-, N) 2009 AMADEUS @DA NE (K-, N) 2010 FAIR. . . What about theory? Need for Calculations of FSI p. K+ Interpretation of the FOPI p excess in Al+Al and Ni+Ni. . LEANNIS Network proposal at FP 7 for this particular issue. .
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