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Lambd a hypernuclear spectroscopy up to medium heavy mass number at JLab Hall-C

Lambd a hypernuclear spectroscopy up to medium heavy mass number at JLab Hall-C. Graduate school of Science, Tohoku Univ. Toshiyuki Gogami. Contents. Introduction Experimental setup Analyses Missing mass Summary. Contents. Introduction Experimental setup Analyses Missing mass

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Lambd a hypernuclear spectroscopy up to medium heavy mass number at JLab Hall-C

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  1. Lambda hypernuclear spectroscopy up to medium heavy mass number at JLab Hall-C Graduate school of Science, Tohoku Univ. Toshiyuki Gogami

  2. Contents • Introduction • Experimental setup • Analyses • Missing mass • Summary

  3. Contents • Introduction • Experimental setup • Analyses • Missing mass • Summary (e,e’K+) reaction e e u u γ* K+ – u s p d s u Λ d

  4. Λhypernuclear spectroscopy 52LV Updated from: O. Hashimoto and H. Tamura, Prog. Part. Nucl. Phys. 57 (2006) 564.

  5. Spectroscopic experiment by the (e,e’K+) reaction pe’ e + p➝ e’ + K+ + Λ e- e’-Spectrometer γ* Coincidence Missing Mass MHY p K+ Λ n K+-Spectrometer pK+ target nucleus • ~ 1990’s • The (K-,π-) , (π+,K+) reactions • Energy resolution ~ a few MeV • n Λ • 2000~ • The (e,e’K+) reaction • Energy resolution ~0.5 MeV • p  Λ

  6. Experimental motivation • JLab E05-115 (2009, Hall-C) • Elementary processes (Λ,Σ0) • 7ΛHe[1], 9ΛLi, 10ΛBe • ΛN charge symmetry breaking • ΛN-ΣN coupling • 12ΛB[2][3][4] • Consistency check with the past experiments • Check analysis progress • 52ΛV • Single particle energy • For measurements with heavier targets [1]S.N.Nakamura et al., PRL 110, 012502 (2013) [2] T.Miyoshi et al., PRL 90, 232502 (2003) [3] L.Yuan, PRC 73, 044607 (2006) [4] M.Iodice, PRL 99, 052501 (2007)

  7. Contents • Introduction • Experimental setup • Analyses • Missing mass • Summary HES

  8. Experimental setup(E05-115 @ JLab Hall-C) 10 msr 10 msr

  9. Contents • Introduction • Experimental setup • Analyses • Missing mass • Summary

  10. Analysis

  11. Analysis x, x’, y, y’ x, x’, y, y’ @ Reference plane @ Reference plane p, x’, y’ p, x’, y’ @ Target Missing Mass

  12. Energy scale calibration x, x’, y, y’ @ RP Polyethylene target (0.45 g/cm2) e, K+ Inverse transfer matrix FWHM ~ 1.8 MeV p, x’, y’@ Target

  13. Contents • Introduction • Experimental setup • Analyses • Missing mass • Summary

  14. 10ΛBe, 12ΛB histograms 10B(e,e’K+)10ΛBe FWHM~0.9 MeV NsΛ~190 12C(e,e’K+)12ΛB Preliminary Analyses are in progress to achieve better energy resolution with keeping good linearity. FWHM~0.9 MeV sΛ sΛ Quasi-free Λ pΛ NsΛ~530 Preliminary Accidental Background Quasi-free Λ Accidental Background T.Motoba et al., PTP Supplement 185 ( 2010 )

  15. Summary and outlook • JLab E05-115 (2009) • Λ, Σ0, 7ΛHe, 9ΛLi, 10ΛBe, 12ΛB, 52ΛV • Analyses are in progress • Matrix tuning • Blind analysis • Efficiencies

  16. E05-115 collaboration

  17. Backup

  18. New challenging experiment (e,e’K+) spectroscopy 1m • Λ, Σ0 • Elementary process • Energy scale calibration • 12ΛB • Consistency check • 27ΛMg, 48ΛSc • Deformation • 208ΛTl • Single particle energy e- γ* p K+ Λ n target nucleus

  19. New challenging experiment (e,e’K+) spectroscopy 1m • Λ, Σ0 • Elementary process • Energy scale calibration • 12ΛB • Consistency check • 27ΛMg, 48ΛSc • Deformation • 208ΛTl • Single particle energy π- Decayed pion spectroscopy • 4ΛH • Charge symmetry breaking p Λ n target nucleus

  20. New challenging experiment (e,e’K+) spectroscopy 1m • Λ, Σ0 • Elementary process • Energy scale calibration • 12ΛB • Consistency check • 27ΛMg, 48ΛSc • Deformation • 208ΛTl • Single particle energy • Design and setup • 3-D magnetic field calculation • Monte Carlo simulation • Experimental operation • Analyses • Energy scale calibration • Tracking Decayed pion spectroscopy • 4ΛH • Charge symmetry breaking

  21. Background events in the HKS REAL DATA SIMULATION 9Be , 38.4 [μA] • 52Cr target • Luminosity ( 1/10 ) • Worse S/N • Tracking is not easy KDC1 x [cm] KDC2 y [cm] KDC1 e+ KDC2 z [cm]

  22. Tracking efficiency and residual σ ~ 160 μm σ ~ 350 μm Plane efficiency Tracking residual

  23. 52Cr(e,e’K+)52ΛV Preliminary Quasi-free Λ Accidental Background Nbind~870

  24. Hit wire selection REAL DATA CH2 Target CUT CUT 52Cr Target REAL DATA Black : hit wires Blue : selected wires Red : track • Compared to the conventional code • Number of K++130% • Analysis time – 30%

  25. 軽い核のミッシングマス 数、分解能 JLab E05-115, Carbon (112mg/cm2) 10LBe

  26. Energy scale calibration conversion Angle, position @ FP Angle, momentum @ Target Mx – MΛ < 100 keV/c2 e, K+ 6th order transfer matrix

  27. トラッキング困難 CH2 Target H2O Target REAL DATA REAL DATA Black : hit wires Blue : selected wires Red : track

  28. 52LV

  29. Singles rate summary HKS Up to ~30 [MHz] HKS trigger ~ 10[kHz] HES Up to ~15 [MHz] COIN 2.0 [kHz] HES trigger ~ a few[MHz] HKS-HES Collaboration Meeting, T.Gogami

  30. B.G. mix rate (real data) b a B.G mix rate = HKS-HES Collaboration Meeting, T.Gogami * hks ntulpe

  31. e+ simulation • To see • Number of event • Angle & momentum of e+ generated in target SIMULATION HKS-HES Collaboration Meeting, T.Gogami

  32. Spectroscopic experiment by the (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 • ~ 1990’s • The (K-,π-) , (π+,K+) reactions • Energy resolution ~ a few MeV • n Λ • 2000~ • The (e,e’K+) reaction • Energy resolution ~0.5 MeV • p  Λ JPS meeting in Kyoto , Toshi Gogami

  33. Background events in the HKS REAL DATA SIMULATION 9Be , 38.4 [μA] KDC1 x [cm] • 52Cr target • Luminosity ( 1/10 ) • Worse S/N • Tracking is not easy KDC2 y [cm] KDC1 e+ KDC2 z [cm] ~2.24 ~4.94

  34. 10ΛBe, 12ΛB histograms 10B(e,e’K+)10ΛBe 12C(e,e’K+)12ΛB NsΛ~190 FWHM~0.9 MeV FWHM~0.9 MeV sΛ sΛ pΛ Preliminary Preliminary Quasi-free Λ Quasi-free Λ Accidental Background Accidental Background NsΛ~530

  35. Experimental motivation • JLab E05-115 (2009, Hall-C) • Elementary processes (Λ,Σ0) • 7ΛHe[1], 9ΛLi, 10ΛBe • ΛN charge symmetry breaking • ΛN-ΣN coupling • 12ΛB • Consistency check with the past experiments • Check analysis progress • 52ΛV • Single particle energy (systematic なstudy) • ls splitting, core-configuration mixing • 将来重く行くため避けられない道 [1]S.N.Nakamura et al., PRL 110, 012502 (2013)

  36. Detectors & Trigger HKS K+ p, π+ HES e- TOF walls (Plastic scintillators) HES trigger (TOF1x2) ~2000 kHz HKS trigger (TOF1x2x3) x Chrenkov ~10 kHz • Cherenkov detectors • Aerogel (n=1.05) • Water (n=1.33) Coincidence trigger HES x HKS < 2 kHz Drift chambers Core2Core in Barcelona, Toshi Gogami

  37. 52Cr(e,e’K+)52ΛV f d p Preliminary 数 s Mixed event analysis をやる

  38. Electro-production of K+Λ JLab E05-115 experiment by the (e,e’K+) reaction Small Q2 ( ~0.01 [GeV/c]2 )  almost real photon Real photon JPS meeting in Hiroshima , Toshi Gogami

  39. An importance of measurement of K+Λproduction at forward angles At forward angles • Data show lack of consistency • We can access θKcm ~ 15 deg Real photon Q2 = 0 [ GeV/c ]2 P.Bydzovsky and T.Mart, Phys. Rev. C 76, 065202 (2007) JPS meeting in Hiroshima , Toshi Gogami

  40. Λ, Σ0 from polyethylene ( CH2 )target Preliminary JPS meeting in Hiroshima , Toshi Gogami

  41. Λ, Σ0 from CH2 target JLab E05-115 CH2, ~ 450 [mg/cm2] ~ 2.0 [μA] ~ 38 [hours] p(e,e’K+)Λ ~1.8MeV (FWHM) Δm = 19 ± 17 keV/c2 Preliminary p(e,e’K+)Σ0 ~1.8MeV (FWHM) Δm = 73 ± 47 keV/c2 JPS meeting in Hiroshima , Toshi Gogami

  42. Cross sections Preliminary 85 ± 13 ±34 Preliminary 200 ± 16 ± 91 γ(*) + p  K+ + Λ γ(*) + p  K+ + Σ0 SAPHIR : K.H. Glander et al. , Eur. Phys. J. A 19, 251-273 (2004) CLAS : R. Bradford et al. , Phys. Rev. C 73, 035202 (2006) JPS meeting in Hiroshima , Toshi Gogami

  43. Cross sections Preliminary 85 ± 13 ±34 Preliminary 200 ± 16 ± 91 γ(*) + p  K+ + Λ γ(*) + p  K+ + Σ0 SAPHIR : K.H. Glander et al. , Eur. Phys. J. A 19, 251-273 (2004) CLAS : R. Bradford et al. , Phys. Rev. C 73, 035202 (2006) JLab E94-107 : P. Markoviz et al. , Proceedings of SENDAI08 (2009) JLab E91-016 : F. Dohrmann et al. , arXiv 0707.3059v2 (2007) JPS meeting in Hiroshima , Toshi Gogami

  44. Q2 dependence (JLab E05-115) W = 1.93 GeV θCM = 17 degrees JLab E05-115, CH2 target Preliminary 実光子 (SAPHIR) JPS meeting in Hiroshima , Toshi Gogami

  45. Apply to u,v-layer v v’-layer Selective region determined by 1X and 2X Applied to uu’ and vv’ layers , too. Convert xx’-layer JPS meeting in Kyoto , Toshi Gogami

  46. Hit wires event display (2) KDC1 KDC2 v v’ v v’ uu’ uu’ • GREEN regionSelective region • RED markers & linesSelected hit wires • BLACK markers & lines Rejected hit wires particle particle x x’ x x’ JPS meeting in Kyoto , Toshi Gogami

  47. Detectors & Trigger HKS K+ p, π+ HES e- TOF walls (Plastic scintillators) • Cherenkov detectors • Aerogel (n=1.05) • Water (n=1.33) Drift chambers Core2Core in Barcelona, Toshi Gogami

  48. Detectors & Trigger HKS K+ p, π+ HES e- TOF walls (Plastic scintillators) HES trigger (TOF1x2) ~2000 kHz HKS trigger (TOF1x2x3) x Chrenkov ~10 kHz • Cherenkov detectors • Aerogel (n=1.05) • Water (n=1.33) Coincidence trigger HES x HKS < 2 kHz Drift chambers Core2Core in Barcelona, Toshi Gogami

  49. Coincident K+ Identification (OFF-LINE) Cherenkov selection Coincidence time selection Water (n=1.33) Aerogel (n=1.05) Coincident K+ : ~90% ( π+ : < 1% , p : < 2% ) CUT CUT ( e,e’p ) CUT CUT CUT p ( e,e’K+ ) K+ π+ CUT ( e,e’π+ ) = HKST - HEST p cut π+ cut Coincidence of (e,e’K+) selection mK2 selection Core2Core in Barcelona, Toshi Gogami

  50. 10ΛBe, 12ΛB histograms 10B(e,e’K+)10ΛBe 12C(e,e’K+)12ΛB NsΛ~190 FWHM~0.9 MeV FWHM~0.9 MeV sΛ sΛ pΛ Preliminary Preliminary Quasi-free Λ Quasi-free Λ Accidental Background Accidental Background NsΛ~530

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