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AMADEUS

AMADEUS. A ntikaon M atter A t D A  NE: E xperiments with U nraveling S pectroscopy. 32 nd Meeting of the LNF Scientific Committee 31 st May – 1 st June 2006. C. Guaraldo. Contents. Introduction The case of AMADEUS The framework of the AMADEUS Proposal Realizing AMADEUS

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AMADEUS

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  1. AMADEUS AntikaonMatter AtDANE:Experiments withUnravelingSpectroscopy 32nd Meeting of the LNF Scientific Committee 31st May – 1st June 2006 C. Guaraldo C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  2. Contents • Introduction • The case of AMADEUS • The framework of the AMADEUS Proposal • Realizing AMADEUS • Determination of the neutron detection efficiency of the KLOE e.m. calorimeter • Implementation of the AMADEUS setup within KLOE • Analysis of the Helium data of the KLOE Drift Chamber • Conclusions C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  3. 1. Introduction C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  4. Letter of Intent Study of deeply bound kaonic nuclear states at DANE2 AMADEUS Collaboration March 2006 C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  5. 111 scientists from 33 Institutes of 13 Countries signed the Letter of Intent C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  6. 2. The case of AMADEUS C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  7. The case of AMADEUS • Problem How the spontaneous and explicit chiral symmetry breaking pattern of low energy QCD changes in the nuclear environment How the hadron masses and interactions changes in the nuclear medium • Approach New type of in-medium hadron mass spectroscopy • Method Producing deeply bound states from which to deduce the hadron-nucleus potential and the in-medium hadron mass

  8. Deeply bound pionic atoms Successful example of deeply bound mesonic states Deeply bound states in pionic atoms T. Yamazaki, P. Kienle et al., Z. Phys. A355 (1996) 219 Subtle balance at the surface of a heavy nucleus between the Coulomb attraction and the repulsion resulting from the pion-nuclear strong interaction. • Important tool for testing chiral pion-nucleus dynamics and studying partial chiral symmetry restoration W. Weise, Acta Phys. Pol. B31 (2000) 2715 P. Kienle and T. Yamazaki, Phys. Lett. B514 (2001) 1 P. Kienle, T. Yamazaki, Progress in Particle and Nuclear Physics 52 (2004) 85.

  9. Deeply bound kaonic nuclear states • Deeply bound kaonic nuclear states in presence of a strong KN attractive potential were firstly suggested by WycechS. Wycech, Nucl. Phys. A450 (1986) 399c • A “new paradigm” in strangeness nuclear physics can be considered the work “Nuclear bound states in light nuclei” by Y. Akaishi and T. Yamazaki Phys. Rev. C65 (2002) 044005 Strong attractive I=0 KN interactionfavors discrete nuclear states bound100-200 MeV and narrow 20-30 MeV shrinkageeffectof a K on core nuclei

  10. The KN interaction • Deeply bound kaonic nuclear states require the presence of a strong attractive KN interaction in the isospin I=0 channel However, apparently, from experiments: • S-waveK-nucleonscattering length isnegativeat threshold “repulsive type” interaction A.D. Martin, Nucl. Phys. B179 (1981) 33 • K line shiftof kaonic hydrogenisnegative  “repulsive type” interaction KEK: M. Iwasaki et al., Phys. Rev. Lett. 78 (1997) 3067 DEAR: G. Beer et al., Phys. Rev. Lett. 94 (2005) 212302 C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  11. Results on the shift and width for kaonic hydrogen Kb Ka 1000 Counts/ 60 eV Kg 800 X-ray energy (keV) attractive repulsive KpX (KEK) M. Iwasaki et al, 1997 600 Izycki et al, 1980 widthG1s[eV] DEAR 400 = - 323 ± 63 ± 11 eV  = 407 ± 208 ± 100 eV SIDDHARTA 200 Bird et al, 1983 Davies et al, 1979 0 -500 0 500 shifte1s[eV] DEAR results: G. Beer et al., Phys.Rev.Lett. 94, (2005)212302 1s = - 193 ± 37(stat) ± 6(syst) eV 1s = 249 ± 111(stat) ± 30(syst) eV X-ray energy (keV) klk

  12. In-medium effects on the dynamics of the  (1405) • If the s-wave, isospin I=0 (1405) resonance is dominantly a KN bound state  the actual K-p interaction isattractive although it appears repulsive in the scattering length and the K energy shift of kaonic hydrogen C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  13. In-medium effects on the dynamics of the  (1405) influence of the nuclear medium on (1405) formation strong non-linear density dependence of optical potential: repulsion infree spaceattraction in nuclear matter • this comes from experiments: result of a systematic phenomenological re-analysis of kaonic atoms dataE. Friedmann, A. Gal and C.J. Batty, Phys. Lett. B308 (1993) 6; Nucl. Phys. A579 (1994) 518. • mechanism: Pauli principle on proton weakening of binding  (1405) mass shift up to threshold C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  14. Influence of the nuclear medium (Pauli blocking) on the formation of the Λ(1405) T. Waas, N. Kaiser, W. Weise, Phys. Lett. B 365 (1996) 12 In free space, at threshold, point A, aK-p<0 repulsive interaction In nuclear matter at rather low density (0.2 0), at threshold, point B, aK-p>0 attractive interaction B A K- p threshold 1432 Fig. 1. Real (dashed lines) and imaginary parts (solid lines) of the K- pscattering amplitude in nuclear matter at different values of the Fermi momentum pF= (3π2 ρ/2)1/3, as a function of the total c.m. energy √s . a) free space, pF = 0; b)~ 0.2 ρ0, pF = 150 MeV/c; c)~ 1.4 ρ0, pF = 300 MeV/c; ρ0= 0.17 fm-3

  15. Role of a bound state below threshold The behavior of the K-p potential is a phenomenon well known in nuclearphysics • Simple arguments from low-energy scattering show that the existence of a bound state below threshold always leads to a repulsive scattering length.M.A. Preston and R.K. Badhuri, Structure of the nucleus, Addison-Wesley, Reading, Massachusetts, 1974 • Analogy between the K-p scattering in the I=0 channel and the proton-neutron (p-n) scattering in the deuteron channel (I=0, S=1): the interaction between the proton and neutron is attractive, but the scattering length in the deuteron channel (I=0, S=1) is repulsive, due to the existence of the deuteron as a bound state. In nuclear matter, however, the deuteron disappears, largely due to Pauli blocking, and the true attractive nature of the p-n interaction emerges.

  16. 3. The framework of the AMADEUS Proposal C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  17. The framework of the AMADEUS Proposal • Experiments Present:KEK E471, E549, E570 DANE FINUDA GSI FOPI analyses of the recently collected data are in progress Future:new data from FOPI, FINUDA and JPARC • Theory • Debate in progress, including alternative interpretations of the data so far obtained • - Another “kaonic hydrogen puzzle” – likestory?until new reliable experimental results are on the market?

  18. AMADEUS philosophy/ strategy • The only way to confirm, or deny, the exotic states is to perform a good measurement using a high performance detector on the most suitable accelerator a measurement NOT performed until now complete determination of all formation and decay channels binding energies, partial and total widths, angular momenta, isospin, sizes, densities, etc  Detection of charged particles, neutrons and photons up to about 800 MeV/c in 4 geometry Requirements satisfied by the performance of the KLOE detector C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  19. 4. Realizing AMADEUS C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  20. Realizing AMADEUS • determination of the neutron detection efficiency of the KLOE e.m. calorimeter • Implementation of the AMADEUS setup within KLOE • Analysis of the KLOE Drift Chamber Helium data C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  21. 5. Determination of the neutron detection efficiency of the KLOE e.m. calorimeter C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  22. Strange tribaryon formation The (pnnK-) kaonic cluster may decay through the following channels: (ppnK-) L + d L + np S- + pp S0 + d S0 + np with the L and S’s decaying according to PDG. K- + 4He  (ppnK-) + n C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  23. P(p) GeV/c P(n) GeV/c P(L) GeV/c Range of interest of neutron energies The ejected primary neutrons in the formation process (“monochromatic” component) have a momentum of about 510 MeV/c (energy about 140 MeV). Neutrons produced in the tribaryon decay channel Lpn (“continuous” component) have momenta starting from few tens MeV/c till about 600 MeV/c (energy about 180 MeV) C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  24. Determination of the KLOE calorimeter efficiency for neutrons • MonteCarlo simulationsAMADEUS MonteCarlo GEANT simulation (and FLUKA MonteCarlo from KLOE) • Measurement with a neutron beamKLOE+AMADEUS experimental test of a prototype of the KLOE calorimeter on the neutron beam of TSL (Uppsala): KLONE proposal C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  25. A prelimnary GEANT MonteCarlo simulation of the KLOE calorimeter: extraction of the efficiency for neutron detection AMADEUS Technical Note IR-1, 4 March 2006 M. Cargnelli STEFAN MEYER Institute for Subatomic Physics, Vienna, Austria C. Curceanu Laboratori Nazionali di Frascati dell’INFN, Frascati, Italy C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  26. KLOE calorimeter C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  27. The calorimeter MC model One quarter of the calorimeter was modelled, the azimuthal angle 0-90 degrees was subdivided in 6 modules. Each module consisted of a lead converter with an inner radius of ~ 200 cm and ~ 23 cm width. The total length was 4,3 m. In these 6 volumes the fibres were placed as copies of cylindrical volumes with 1 mm diameter, by taking the tangential pitch of 1.35 mm and the radial pitch of 1.2 mm. C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  28. GEANT 3.21 simulation - inputs The neutrons were started isotropically from the centre of the apparatus (the beam interaction point). The neutron momentum was sampled uniformly between 100-1300 MeV/c. The sum of deposited energies in the fibres (starting from 0 ‘no signal generated’) of one module was histogrammed versus the incoming neutron energy. The ratio of the number of neutrons depositing energy versus the total number of incoming neutrons gives the intrinsic efficiency. The values are given for 2 lower thresholds of the deposited energy: 3 and 1 MeV. Only signal produced by protons was taken into account.

  29. GEANT 3.21 simulation example of events

  30. GEANT 3.21 simulation – example of events

  31. MonteCarlo simulation - Calorimeter response Neutron detection efficiency Threshold at 1 MeV Threshold at 3 MeV C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  32. Results in agreement with FLUKA dedicated simulations performed by KLOE. Refined MonteCarlo simulations to understand details (topology, etc.) are undergoing. C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  33. Measurement of the neutron efficiency using a test beam Test of a calorimeter prototype on a neutron beam: KLOE + AMADEUS, mixed team of ~ 15 persons, lead by Stefano Miscetti C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  34. The KLONE proposal at TSL (Uppsala) KLONE (KLOe NEutrons) formal request to TSL in April 2006 Stefano Miscetti and Catalina Curceanu Funded with European Transnational Access budget of TSL within the FP6 HadronPhysics Project C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  35. The KLOE calorimeter prototype for KLONE: • dimensions: ~ 25 x 13 x 60 cm3, instrumented on both sides (32 PMs in total) • cut from a prototype of the KLOE calorimeter C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  36. C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  37. The TSL neutron beam at Uppsala (1) Neutrons are produced in the Blue Hall of TSL by the 7Li(p,n) reaction. The proton beam can be varied in the 20-180 MeV range. The resulting neutron energy distribution is such that half of the neutrons are concentrated within 1-2 MeV, at few MeV below the incident proton energy. The remaining neutrons are roughly equally distributed in energy from zero up to the maximum neutron energy. After passage through the production target, the proton beam is deflected in a magnet and dumped far away from the testing area to minimize background.

  38. The TSL neutron beam at Uppsala (2) Neutrons emitted in the forword direction pass through a collimator consisting of iron rings of various diameters, such that any neutron beam diameter from zero up to 30 cm, in steps of 5 cm, can be accomplished. The testing position can be chosen anywhere from just after the collimator up to 10 m away from it (where the neutron beam is 130 cm diameter). The neutron beam facility is equipped with a fission based monitor, which provides a flux measurement with 10% absolute precision. C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  39. Blue Hall at TSL and neutron beam KLONE setup

  40. Performed actions • 15-16 May 2006: visit at TSL and discussions with TSL staff for details: • checked the beam quality compatibility with the goal of themeasurement – OK • checked the geometry of Blue Hall and possible positioning of setup – OK • checked the control room availability – OK • assured participation and support from TSL staff C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  41. KLONE Project at TSL - approved on 18/05/2006 code F183 assigned - beam time allocated in October 2006:week 42 and 43 in Frequency Modulation (FM) mode (100-180 MeV energy range) C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  42. Future working plan • Preparation of the KLONE setup will start in July (when setup at disposal) • Test of the setup at LNF – until October 2006 – optimization • October 2006: transportation and measurements at TSL C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  43. 6. Implementation of the AMADEUS setup within KLOE C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  44. AMADEUS setup within KLOE KLOE – EMC KLOE – Drift Chamber Possible setup for AMADEUS within KLOE: Cryogenic target Inner tracker Kaon trigger C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  45. AMADEUS setup • There are presently 2 versions: • without a vertex/inner tracking detector(minimal version) • - with a vertex/inner tracker detector C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  46. The kaon trigger • The same in both versions with half toroidal cryogenic target • optimal solution for a kaon trigger system, consisting of: • two cylindrical inner-layer scintillating fibres detectors:x-y position within ± 1mm due to an angle of 60° between the two layers • three half cylindrical outer-layer scintillating fibres detectors • with inner and outer scintillating fibres layers a track reconstruction is possible, therefore with the magnetic field of KLOE K+ and K- are distinguishable

  47. AMADEUS setup-minimal version half-toroidal cryogenic target cell 1st inner-layer of scintillating fibre fiber size: 1x1mm2 three outer-layers of scintillating fibre fiber size: 1x1mm2 2nd inner-layer of scintillating fibre fiber size: 1x1mm2 (with the collaboration of Vincenzo Patera) C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  48. We need the position of the K- stop = primary vertex Then the kaon tracker might be essential (under study) Second version of AMADEUS setup C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  49. AMADEUS setup- second version (in collaboration with KLOE - for vertex detector) • KLOE and AMADEUS had few meetings in which the vertex/inner tracking detector was discussed • A common solution is emerging: location of the detector in such a way that both KLOE and AMADEUS can use it • Technical solutions (type of detector) and plans for prototyping and testing are being discussed and under evaluation C. Guaraldo - 32nd Meeting of LNF Scientific Committee, 31st May -1st June 2006

  50. AMADEUS setup- second version (in collaboration with KLOE - for vertex detector) • A tracking/vertex detector (a Time Projection Chamber (TPC) with GEM-readout in this example) is surrounding the half toroidal cryogenic target cell with the (previous) kaon trigger configuration. • Alternative, if the background rate is too high (to be checked with FINUDA inner-tracker) a multi-layer cylindrical GEM detector is in discussion: might be necessary

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