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HLAB meeting

HLAB meeting. Status Report Toshi Gogami 1/Nov/2011. JLab E05-115 collaboration, 2009, JLab Hall-C. Contents. ( e,e’K + ) experiments in JLab & Mainz. JLab E05-115 (2009) The number of events for high multiplicity data. JLab & Mainz. e + p ➝ e’ + K + + Λ.

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HLAB meeting

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  1. HLAB meeting Status Report Toshi Gogami 1/Nov/2011 JLab E05-115 collaboration, 2009, JLab Hall-C

  2. Contents • (e,e’K+) experiments in JLab & Mainz. • JLab E05-115 (2009) • The number of events for high multiplicity data

  3. JLab & Mainz e + p➝ e’ + K+ + Λ

  4. Spectroscopic experiment by (e,e’K+) reaction pe’ e + p➝ e’ + K+ + Λ Feynman diagram e- e’-Spectrometer e e u u γ* K+ – γ* u s Coincidence p Missing Mass HHY d s p K+ u Λ Λ d n K+-Spectrometer pK+ target nucleus • Large Momentum transfer • Λ can be bounded in deeper orbit • Λ’s spin at forward angle • Spin flip ~ spin non-flip • Proton  Λ,Σ0 • Absolute mass scalecalibration

  5. Experimental setup of JLab E05-115 p(e,e’K+)Λ,(Σ0) HES e’ Splitter Magnet HKS K+

  6. Experimental setup of JLab E05-115 Data taking : Aug-Nov 2009 p(e,e’K+)Λ Tracking 2×10-4 7 [msr] 3 – 12 [deg] 2×10-4 8.5 [msr] 2 – 12 [deg] 7Li , 9Be , 10B , 12C , 52Cr ( 7ΛHe , 9ΛLi , 10ΛBe , 12ΛB , 52ΛV ) 2 - 50 [μA] 10 - 300 [THz] CH2, H2O

  7. Discrepancy of Number of Λ CH2 Target H2O Target Λ Λ • The number of Λ • NΛ ¼ Nexpect • The number of Λ • NΛNexpect Lost events that we are interested in in tracking procedure. Very preliminary Very preliminary Σ0 Σ0 12C quasi-free 16O quasi-free Acc. b.g. Acc. b.g. REAL DATA REAL DATA Black : hit wires Blue : selected wires Red : track Black : hit wires Blue : selected wires Red : track ECT*/JSPS core to core, T.Gogami (2011)

  8. New tracking code

  9. Results of Introduction of new Tracking Code CH2 • NΛ¼ Nexpect  NΛ½ Nexpect Increased ! 52Cr Increased ! H2O

  10. For further improvement • Efficiency • Tracking • TOF detectors • Discarded events

  11. Rates of the KDC wires 52Cr, 77124 KDC1-u KDC1-u’ KDC1-x KDC1-x’ KDC1-v KDC1-v’ 52Cr, 77124 < 510 kHz < 350 kHz Rate [kHz] 77124 ( 52Cr target ) KDC2 KDC1 Wire Number 5 × 5 ~11 MHz ~22 MHz KDC2-u’ KDC2-x KDC2-x’ KDC2-v KDC2-v’ KDC2-u < 290 kHz < 230 kHz

  12. Rates of the HKS TOF detectors

  13. Events which are discarded KDC2 KDC1 52Cr, 77124

  14. Events which are discarded KDC2 • Where and why are these events discarded ? • Are these events threw away bycorrect cut condition? KDC1 52Cr, 77124

  15. Summary • Need to improve analysis code for high multiplicity data • Efficiencies • Rescue discarded events

  16. END JLab Hall-C circuit room, 5/Nov/2009

  17. Backup

  18. Decay Pion Spectroscopy to Study -Hypernuclei Direct Production e’ Example: K+ 12C e * Ground state doublet of 12B B and  p  12B  E.M. 12Bg.s. Hypernuclear States: s (or p) coupled to low lying core nucleus 2- ~150 keV 1- 0.0 -  12C Weak mesonictwo body decay

  19. Decay Pion Spectroscopy for Light and Exotic -Hypernuclei Fragmentation Process Example: e’ K+ Access to variety of light and exotic hypernuclei, some of which cannot be produced or measured precisely by other means 12C e * Fragmentation (<10-16s) p s 12B* 4H  4Hg.s. Highly Excited Hypernuclear States: s coupled to High-Lying core nucleus, i.e. particle hole at s orbit   -  Weak mesonictwo body decay (~10-10s)   4He

  20. Spectroscopic experiment by (e,e’K+) reaction pe’ e + p➝ e’ + K+ + Λ Feynman diagram e- e’-Spectrometer e e u u γ* K+ – γ* u s Coincidence p Missing Mass HHY d s p K+ u Λ Λ d n K+-Spectrometer pK+ target nucleus • Large Momentum transfer • Λ can be bounded in deeper orbit • Λ’s spin at forward angle • Spin flip ~ spin non-flip • Proton  Λ,Σ0 • Absolute mass scalecalibration

  21. JLab E05-115 experimental setup e + p → e’ + Λ + K+ 7Li , 9Be , 10B , 12C , 52Cr 2×10-4 7 [msr] 3 – 12 [deg] 2×10-4 8.5 [msr] 2 – 12 [deg] • (e,e’K+) experiment • Coincidence experiment (K+ and e-) • Small cross section ( ~100 [nb/sr] ) 1/1000 • Energy resolution Sub MeV (FWHM) • Primary beam • High intensity • Thin target (~100 [mg/cm2]) • High quality APFB2011 in Korea (T.Gogami)

  22. Experimental setup of JLab E05-115 Data taking : Aug-Nov 2009 p(e,e’K+)Λ HKS chamber wire configuration Tracking 2×10-4 7 [msr] 3 – 12 [deg] 2×10-4 8.5 [msr] 2 – 12 [deg] 7Li , 9Be , 10B , 12C , 52Cr ( 7ΛHe , 9ΛLi , 10ΛBe , 12ΛB , 52ΛV ) 2 - 50 [μA] 10 - 300 [THz] CH2, H2O

  23. HKS Drift Chamber hit selectionwith TOF detectors Gravity • GREEN region Selective region • RED markers Selected hit wires • BLACK markers Rejected hit wires Particle direction

  24. Results of Introduction of new Tracking Code CH2 • NΛ¼ Nexpect  NΛ½ Nexpect Increased ! 52Cr Increased ! H2O

  25. Theoretical calculation of A=7 system -6.650.030.2 MeV from α L n n Four-body cluster model for T=1 triplet hypernuclei (E.Hiyama et al., NPC 80, 2009) α+ Λ + N + N JLab E01-011 7Li(e,e’K+)7ΛHe Preliminary -BL (MeV) CSB interaction is determined to reproduce BΛ of 4ΛH and 4ΛHe. APFB2011 in Korea (T.Gogami)

  26. (e,e’K+) experiment in JLab Hall-C Proof of feasibility 12C(e,e’K+)12ΛB E89-009 2000 1st generation exp.JLab E89-009 ENGE(e’) + SOS(K+) 12ΛB ~ 750 [keV] (FWHM) sΛ pΛ ~750 [keV] (FWHM) Establish exp. method 2005 2nd generation exp.JLab E01-011 ENGE(e’) + HKS(K+) + Tilt method 7ΛHe,12ΛB,28ΛAl ~ 500 [keV] (FWHM) 28Si(e,e’K+)28ΛAl E01-011 Confirming stage pΛ dΛ sΛ Up to Medium heavy 2009 3rd generation exp.JLab E05-115 HES(e’) + HKS(K+) + Tilt method 7ΛHe,9ΛLi,10ΛBe,12ΛB,52ΛV ≤ 500 [keV] (FWHM) ~600 [keV] (FWHM) Preliminary APFB2011 in Korea (T.Gogami) Analysis stage

  27. (e,e’K+) experiment in JLab Hall-A 12C(e,e’K+)12ΛB pΛ sΛ 2007 JLab E94-107 HRS’s (K+, e+)+ septum 9ΛLi,12ΛB,16ΛN ~ 670 [keV] (FWHM) 16O(e,e’K+)16ΛN sΛ APFB2011 in Korea (T.Gogami)

  28. HESのバックグラウンド • ハイパー核生成に関係した電子　赤 • HES側のバックグラウンド • 制動放射起因の電子　緑 • Møller散乱起因の電子　青 モンテカルロシミュレーションでそれぞれ150000イベント生成させた • バックグラウンドである、0o方向に集中するMøller散乱・制動放射起因電子を避けるTilt法を導入 e’ rate 　　第一世代　　第二世代 200 [MHz]1 [MHz] Tilt法の概略図 APFB2011 in Korea (T.Gogami)

  29. Tilt角の最適化 • Figure of Merit (FoM) 6.5o • ハイパー核生成に関与した電子の計数率 S • Mφller散乱起因電子の計数率 NMφller • 制動放射起因電子の計数率 NBrems シミュレーションによる計数率の見積もり APFB2011 in Korea (T.Gogami) ビーム強度 30 [μA] , 100 [mg/cm2] を仮定

  30. 角度アクセプタンス 入射電子ビームのエネルギー 1.851 2.344 [GeV] • バックグラウンドがより前方に集中 • アクセプタンスをより前方へ 第二世代実験E01-011 • HESの角度アクセプタンスが広い ハイパー核の収量が増加 第三世代実験E05-115 APFB2011 in Korea (T.Gogami)

  31. 運動量アクセプタンス 52ΛV g.s. 測定するハイパー核の生成領域を広くカバーするように設計した。 Ei=2.344,ω=1.5[GeV] HKSとHESの運度量の相関 立体角 • 一様に生成した全粒子の数をNGen • 一様に生成した全粒子の立体角をΔΩGen • HESの最下流まで通過した粒子の数をNpass 立体角 ~6.5[msr]w/ splitter APFB2011 in Korea (T.Gogami)

  32. 89Y(π+,K+)89ΛY, 51V(π+,K+)51ΛV 1.45 [MeV] (FWHM) KEK-PS E369 89Y(π+,K+)89ΛY KEK-PS E369 51V(π+,K+)51ΛV 89Y(π+,K+)89ΛY KEK-PS E369 12C(π+,K+)12ΛC 51V(π+,K+)51ΛV 12C(π+,K+)12ΛC APFB2011 in Korea (T.Gogami)

  33. E05-115 experimental motivation(2) 1f7/2 FULL(8) f 7+ 6+ or 1d3/2 FULL(4) FULL(4) 6- 5- d • ls splitting • Core excited or ・ ・ ・ ・ ・ ・ 5+ 4+ p ls splitting ∝ 2l+1 or n = 28 p = 24 4- 3- s or 52Cr Λ 52ΛV d p f s Photo- and electro production of medium mass Λ-hypernuclei ,P.Bydzovsky et al. (2008) APFB2011 in Korea (T.Gogami)

  34. Spectroscopic experiment via (e,e’K+) reaction e + p➝ e’ + K+ + Λ Feynman diagram e- e e u u γ* K+ – γ* u s p d s p K+ u Λ Λ d n target nucleus measure Missing mass : M2HY = (Ee + MT - EK+ - Ee’)2 - ( pe - pK+- pe’)2 • Binding energy • Cross section APFB2011 in Korea (T.Gogami)

  35. P.Bydzovsdy ,photo- and electro production of medium mass Λ-hypernuclei, 2008 APFB2011 in Korea (T.Gogami)

  36. Λsingle particle energy • (e,e’K+) experiments in JLab • E89-009 (2000) • E94-107 (2004) • E01-011 (2005) • E05-115 (2009) D.J.Millener et al. PRC 38, 6, 1988 Woods-Saxson potential with a depth of 28 [MeV] and a radius parameter APFB2011 in Korea (T.Gogami)

  37. Feature of (e,e’K+) reaction (e,e’K+) (π+ , K+) (K- , π-) e + p➝ e + K+ + Λ π+ + n➝ K+ + Λ K- + n➝ π- + Λ e e – – u u u u Reaction K+ π+ – – K- π- s s d u d u γ* K+ – u s p d s d s d s n d d n d d u Λ Λ Λ u u u u d Momentum transfer (Typical ) ~300 [MeV/c] ~300 [MeV/c] ~90 [MeV/c] Λ can be bounded in deeper orbit Λ’s Spin At forward angle flip ≈ non-flip non-flip non-flip Spin dependent structure proton neutron neutron Λ’s from Mirror lambda hypernuclei primary secondary secondary Beam High quality , high intensity Target Thin (~100 mg/cm2) (Isotopically enriched) Thick(> a few [g/cm2] ) Thick(> a few [g/cm2] ) Energy resolution (FWHM) APFB2011 in Korea (T.Gogami) ≤ 500 [keV] 1 – 3 [MeV] 1 – 3 [MeV] Fine structure

  38. Theoretical calculation of A=7 system -6.650.030.2 MeV from α L n n Four-body cluster model for T=1 triplet hypernuclei (E.Hiyama et al., NPC 80, 2009) α+ Λ + N + N JLab E01-011 7Li(e,e’K+)7ΛHe Preliminary -BL (MeV) CSB interaction is determined to reproduce BΛ of 4ΛH and 4ΛHe. APFB2011 in Korea (T.Gogami)

  39. (e,e’K+) experiment in JLab Hall-C Proof of feasibility 12C(e,e’K+)12ΛB E89-009 2000 1st generation exp.JLab E89-009 ENGE(e’) + SOS(K+) 12ΛB ~ 750 [keV] (FWHM) sΛ pΛ ~750 [keV] (FWHM) Establish exp. method 2005 2nd generation exp.JLab E01-011 ENGE(e’) + HKS(K+) + Tilt method 7ΛHe,12ΛB,28ΛAl ~ 500 [keV] (FWHM) 28Si(e,e’K+)28ΛAl E01-011 Confirming stage pΛ dΛ sΛ Up to Medium heavy 2009 3rd generation exp.JLab E05-115 HES(e’) + HKS(K+) + Tilt method 7ΛHe,9ΛLi,10ΛBe,12ΛB,52ΛV ≤ 500 [keV] (FWHM) ~600 [keV] (FWHM) Preliminary APFB2011 in Korea (T.Gogami) Analysis stage

  40. (e,e’K+) experiment in JLab Hall-A 12C(e,e’K+)12ΛB pΛ sΛ 2007 JLab E94-107 HRS’s (K+, e+)+ septum 9ΛLi,12ΛB,16ΛN ~ 670 [keV] (FWHM) 16O(e,e’K+)16ΛN sΛ APFB2011 in Korea (T.Gogami)

  41. Elementary process p(e,e’K+)Λ JLab E05-115 p(e,e’K+)Λ,Σ0 ~40 hours (5 shifts) • p(e,e’K+)Λ,Σ0 are used for Energy calibration • Study of elementary process • Consistency check with past experiment Very preliminary APFB2011 in Korea (T.Gogami) R. Bradford et al. , FRC73, 2006

  42. Single Λ hypernuclear spectroscopy • (π+,K+), (K+,π+) spectroscopy • CERN, BNL, KEK • A = 7 – 208 • Resolution (FWHM) ~ a few MeV • γ-ray spectroscopy with Ge detector • KEK, J-PARC • A=7 – 16 • Resolution (FWHM) ~ a few keV • Decay pion spectroscopy • Mainz Univ. • A < 10 • Resolution (FWHM)< 100 keV • (e,e’K+) spectroscopy • JLab, (Mainz Univ.) • A=7 – 52 • Resolution (FWHM) ~ 500 keV Determine Absolute value APFB2011 in Korea (T.Gogami)

  43. (e,e’K+) reaction (e,e’K+) (π+ , K+) (K- , π-) e + p➝ e + K+ + Λ π+ + n➝ K+ + Λ K- + n➝ π- + Λ e e – – u u u u Reaction K+ π+ – – K- π- s s d u d u γ* K+ – u s p d s d s d s n d d n d d u Λ Λ Λ u u u u d Momentum transfer (Typical ) ~300 [MeV/c] ~300 [MeV/c] ~90 [MeV/c] Λ can be bounded in deeper orbit Λ’s Spin At forward angle flip ≈ non-flip non-flip non-flip Spin dependent structure proton neutron neutron Λ’s from Mirror lambda hypernuclei primary secondary secondary Beam High quality , high intensity Target Thin (~100 mg/cm2) (Isotopically enriched) Thick(> a few [g/cm2] ) Thick(> a few [g/cm2] ) Energy resolution (FWHM) APFB2011 in Korea (T.Gogami) ≤ 500 [keV] 1 – 3 [MeV] 1 – 3 [MeV] Fine structure

  44. JLab CEBAF ( Continuance Electron Beam Accelerator Facility ) • Requirement for accelerator • high duty factor • high intensity • smallemittance • small ΔE/E • (e,e’K+) experiment • Coincidence experiment (K+ and e-) • Small cross section ( ~100 [nb/sr] ) 1/1000 • Energy resolution sub MeV (FWHM) CEBAF can satisfy these requirements Thomas Jefferson National Accelerator Facility APFB2011 in Korea (T.Gogami) 100 [m]

  45. (e,e’K+) experiment in JLab Hall-C 2000年 1st generation exp.JLab E89-009 ENGE(e’) + SOS(K+) 12ΛB ~ 900 [keV] (FWHM) Proof of feasibility 2005年 2nd generation exp.JLab E01-011 ENGE(e’) + HKS(K+) + Tilt method 7ΛHe,12ΛB,28ΛAl ~ 500 [keV] (FWHM) Establish exp. method Luminosity ×137 e’ rate 1/200 S/N ×2.7 2009年 3rd generation exp.JLab E05-115 HES(e’) + HKS(K+) + Tilt method 7ΛHe,9ΛLi,10ΛBe,12ΛB,52ΛV ≤ 500 [keV] (FWHM) Medium heavy APFB2011 in Korea (T.Gogami)

  46. JLab E05-115 experiment APFB2011 in Korea (T.Gogami)

  47. E05-115 experimental motivation (1) • 2009 Aug – Nov @ JLab Hall-C • (e,e’K+) reaction • Target : 7Li , 9Be , 10B , 12C , 52Cr First try It is difficult experimentally. “ b.g. electron due to brems. ∝ ~Z2 “ • p-shell(7He , 9Li , 10Be , 12B) • Charge symmetry breaking (CSB) • ΛN-ΣN coupling Λ Λ Λ Λ BΛ[MeV] • Medium heavy (52V) • s-,p-,d-,f-orbit binding energy & cross section • Mass dependence of Λ single particle energy • l・s splitting,core configuration mixing • dΛ, fΛ –state Λ APFB2011 in Korea (T.Gogami) A = 52

  48. JLab E05-115 experimental setup e + p → e’ + Λ + K+ 7Li , 9Be , 10B , 12C , 52Cr 2×10-4 7 [msr] 3 – 12 [deg] 2×10-4 11 [msr] 2 – 12 [deg] APFB2011 in Korea (T.Gogami)

  49. JLab E05-115 experimental setup e + p → e’ + Λ + K+ 7Li , 9Be , 10B , 12C , 52Cr 2×10-4 7 [msr] 3 – 12 [deg] 2×10-4 11 [msr] 2 – 12 [deg] APFB2011 in Korea (T.Gogami)

  50. HKS detectors June 2009 in JLab Hall-C 1 [m] • HKS trigger • CP = 1X ×1Y × 2X • K = WC ×AC •  CP × K − π+ K+ p ~18 [kHz] (8 [μA] on 52Cr) K+ p, π+ Drift chambers -KDC1,KDC2- • Cherenkov detectors -AC,WC- • Aerogel (n=1.05) • Water (n=1.33) TOF walls -2X,1Y,1X- (Plastic scintillators) σ ≈ 200 [μm] TOF σ ≈ 170 [ps] APFB2011 in Korea (T.Gogami)

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