1. Advisors:Rurng-Sheng Guo Wen-Chen Chang Graduate: Su-Yin Wang 2009/06/19, NKNU

2. IIntroduction PPHYDES01 Production NNMR Measurement SSignal Distortion (Appendix) AAnalysis CConclusion and Discussion AAcknowledgement 2

3. Motivation

4. Diffractive production within the vector-meson-dominance model through Pomeron exchange One-pion-exchange OZI uud ss ss-knockout uud-knockout A.I.Titov et al. Phys. Rev. C58 (1998) 2429 4

5. Cross Section at E  = 2.0 GeV Vector-meson- dominance model One pion exchange ss knockout uud knockout A.I.Titov et al. Phys. Rev. C58 (1998) 2429 Pomeron exchange is more ten times than others. Only the Pomeron exchange is clear. The experimental data are from H. J. Besch, G. Hartmann, R. Kose, F. Krautschneider, W. Paul, and U. Trinks, Nucl. Phys. B70, 257 ~1974!. 5

6. Beam-Target double spin asymmetry at E  = 2.0 GeV Strangeness content is assumed to be 0%(Solid), 0.25%(Dashed), 1%(Dot-dashed). (  0,  1 ) is the relative phase between the strange and non-strange amplitudes. A.I.Titov et al. Phys. Rev. C58 (1998) 2429 6

7.  Example: t-channel exchange of Λ(1520) photoproduction  Exchange particle is clear to see, if … ▪ Fix the spin and orientation of initial state particles. ▪ The spin and orientation of final state are measured. 7

8. HD Overview

9. Polarized this Symmetry requirement hetero-HD (boson “D” and fermion “H”) no Symmetry requirement polarization is low 18.6 days 6.3 days 9

10. 10

11. 11

12. 12

13. 13

14.  Advantage and Disadvantage  HD molecule does not contain heavy nuclei such as Carbon and Nitrogen.  Good for experiments observing reactions with small cross section  The HD target needs thin aluminum wires (at most 20% in weight) to insure the cooling.  Target Size  25 mm in diameter; 50 mm in thickness 14

15. 15 Distillator Distillator purify the HD gas up to 99.99%.

16. 16 Dilution Refrigerator System (DRS) DRS is mainly for making the polarized HD target. T=10mK, B=17T

17. 17 Storage Cryostat (SC) SC is to keep HD polarization on the way of the transportation from RCNP to Spring8. In normal case, we measure polarization of HD in SC only. T~1.2K, B=2.5T.

18. 18 Transfer Cryostat (TC) The TC1 is mainly for moving the target from the DRS to the SC. The TC2 is mainly for moving the target from the SC to the IBC T=4.2K, B=0.15T TC2 TC1

19. 19 In Beam Cryostat (IBC) IBC is to cool the target during the experiment at SPring-8. T=0.3K, B=1T.

20. 20

21. TC1SCTC2IBC Magnetic field0.15T1.08T0.15T1.08T Temperature4.2K1.2K4.2K300mK Time0.5 hours3 hours0.5 hours100 days Could we keep the polarization at… Could we achieve high polarization? 21

22. Polarized HYdrogen-DEuteride target for Strangeness (PHYDES)

23. H2H2 HD D2D2 Extraction HD D2D2 Extraction HD [H] = 1.26% In PHYDES01 [D] = 2.07% [HD] =97.66% 23

24. Since TC1 can not work now

25. ProcessSolidify HD P H REF measurin g Aging time IBC condition SC condition TC ~condition P D REF measuring Magnetic field 0T1.08T 0.15T7.26T Temperature14~22K4.2K14mK0.3K1.2K4.2K Time 200811112008111220081114 ~ 20090105 ~ 20090119 ~ 20090122 20090127 ~ 20090129 20080217 Time [HD]=97.66%; 0.68 HD was solidified for PHYDES01. After 53 days aging, the relaxation time in three conditions are measured. 25

27. 27

28.  The net absorption or emission of electromagnetic radiation by the nuclear spin system can be modeled macroscopically as the imaginary component of complex magnetic susceptibility: χ(ω) = χ’(ω) + iχ”(ω), Real part = Absorption part. Imaginary part = Dispersion part.  The vector polarization, P, can be written as which forms the basis for the area methods used to determine polarization. 28

29. 29 Cold finger

30. When receiver coil receives the signal, the signal come from transmitter but not nuclear magnetic resonance can be canceled easily by cancellation circuit. 16MHz 15MHz 14MHz 30

31. 31

32. Appendix

33.  The smallest width of the NMR shape can be estimated from the uncertainty principle.  Precision of frequency.  The non-uniformity of the local magnetic field in a superconductor  The non-uniformity of the local magnetic field from the induced current of aluminums wires and cold finger. 33 Cold finger

34. B real ΔBΔB B center ΔB B center Magnetic field uniformity profile Measurement value Fitting by 4 th -order polynomial 34

35. 35

37.  Preparation of Analysis  Unification of the Signal Amplification  Magnetic Field Adjustment  Data Position Shift  Unification of Bin Size  Phase Adjustment  Extracting the Signal Area (Relaxation Time)  Histogram Method  Model Method  Extracting the Signal Area (Polarization)  Histogram Method  Model with Deviation Method  Error Estimation  Relaxation Time Estimation  Polarization Estimation 37

38. The original data with the sensitivity = (1mVrms/-47dBm) The signal is 10% of original one. We also change the signal shape to positive. 38

39. B -1 B0B0 B1B1 B3B3 B2B2 B -3 B -2 ~ B 50 B -50 ~ reset 39

40. After Peak Shift 40

41.  If bad phase …  If good phase … Quadrature In Phase Quadrature 41

42.  After removing background, for each pulse, start analysis 42

43. 43

44. D:IBC,18hours,θ=0.4H:IBC,332hours,θ=0.75  H model increase decrease increase decrease  D model 44

45. Histogram MethodModel Method

46. Histogram MethodModel Method

47.  Histogram method  Model method H, TC, increase, 47 hours

48.  Histogram method  Model method D, TC, decrease,46hours

49. Zoom in each signal Average of 73 signals 49 Can not shift the position of each signal before taking average.

50. Bad fitting by signal deviation 50

51. 51

52. Gauss deviation=2.6094655E-04 D model at 300mK, 1.08T D model with Gauss deviation 52 Background Normalization Sigma of Smearing Background Normalization

54. Histogram MethodSmearing Model Method

55. polarization at thermal equilibrium state polarization decay function combine two function 55

56. left right combine Original New error 56

57. 57

58. Good consistency Bad consistency 58

59.  When extract the signal area of polarization, peak up the smearing model method.  When extract the signal area of relaxation time, peak up the histogram method. 59 [M]

61. 61 GoalPHYDES01 Temperature during aging10 mK14 mK Magnetic field during aging17 Tesla Time of target production2~3 month53 days ~1 yearT 1 H =106 days; T 1 D =73 days Polarization of H90%Theoretical ： 85 ％ Measured ： 41.4 ％ Polarization of D30 ％ Theoretical ： 25 ％ Measured ： 13.1 ％

62. TC1, TC2SCIBC Magnetic field0.15T1.08T Temperature4.2K1.2K300mK Time0.5 hours3 hours100 days T1HT1H 147 hours281 hours106 days T1DT1D 48 hours303 hours73 days Could we keep the polarization at… Could we achieve high polarization? 62 PHPH PDPD 41.4%13.1%

63.  The production of polarized HD target succeeded. But the polarization degrees measured are much lower than those expected from the thermal equilibrium state of the aging condition. Non-linear relation between the NMR signal height and the polarization degree is considered to be a main source of the low polarization degree.  The relaxation times in the SC and TC condition are found to be long enough compared with the staying time needed for the transportation of the HD target.  The relaxation time in the IBC condition is found to be long enough to produce a new polarized HD target for replacement in continuous experiments. 63

64.  Study of Aging Time  Lower Polarization  NMR Measurement  Improvement of D Polarization  From Success of Polarized HD Target to Using the Polarized HD Target in LEPS Experiment 64

65.  For sweeping magnetic field, one need to break superconductor-state of magnet, and turn the magnet to drive-state. It waste a lot of liquid helium.  If the polarization of D and H are both measured, the magnetic field sweep from 1T to 7T will generate a lot of heat and waste a lot of liquid helium.  The significant change of magnetic field, make the polarization of HD unstable. Cannot be avoided Can be avoided easy by separating the cancellation circuits of H and D, 65

67.  There are still many subjects that we have to work on:  Installation of HD target system in the LEPS experiment hutch.  The transit of HD target from RCNP to SPring-8/LEPS.  Acceptable trigger rate for data taking. 67

68.  Whole HD Members, especially for :  藤原 守、與曽井 優  郡 英輝、太田 岳史  福田 耕治、國松 貴之  上田 圭祐、森崎 知治  Advisors:  郭榮升  章文箴 68

69. Thank you for your kind attention.

70. 70

71. 71

72.  The PHYDES01 use 0.68 mole HD only. The smallest cell size is 34 mm. The biggest size is 80 mm (the length of aluminums)  This result shows the most likely cell position around -14 cm and cell length around 46 mm. 72

73. 73

74. D. Babusci et al., LEGS expt. L18/L19 (1994). The time line from LEGS group

75.  The Difficulties of FAFP and SFT  The concentration of o-H 2 can not be handled easy now.  The concentration of p-D 2 can not be handled easy now. (p-D 2 should be ~0)  The amounts of heat depend on the amounts of HD and RF power.  The relation between concentration of o-H 2 and the relaxation time of H is not well known enough. 75

76. HD Polarization41.4%13.1% Temperature estimate by the polarization (Assume B=17T) ~40mK~27mK  Bad linearity of the NMR signal height.  Bad Thermal conductivity of Al wires or Kel-F NMR coil supporter 76

77. TC1SCTC2IBC Magnetic field0.15T2T0.15T1T Temperature4.2K1.2K4.2K300mK Time0.5 hours3 hours0.5 hours100 days H Relaxation time~147 hours~277 hours~147 hours~2546 hours Remained Polarization of Init P H 99.66%98.58%98.24%38.27% Init P H = 41.4 %41.4640.8140.6714.62 D Relaxation time~48 hours~303 hours~48 hours~1740 hours Remained Polarization of Init P D 98.96%97.98%96.96%24.41% Init P D = 12.2 %12.07%11.83% 2.95%

78. Hysteresis from cold finger and aluminum wire 78

79. 79

80.  NMR system – to correctly measure the polarization.  NMR system – to increase Signal/Noise ratio.  Al wires or NMR coil supporter -to decrease the HD temperature.  Distillator - to improve the purity of HD 80

81.  Practice of transferring the target by using a solid H2 target  A polarized HD target after the aging of 2~3 months will be ready for the experiment.  install the HD target system in the LEPS experiment hutch. (  Support frames for the IBC and TC2 will be constructed.  IBC and TC2 will be transferred from RCNP to SPring-8/LEPS.  Circularly polarized ultra-violet laser beam will be prepared.  Check the polarization of the HD target can be kept when the photon beams of ~1 M γ‘s hit the target.  Check trigger rate for data taking is acceptable. 81

82.  Histogram area  Histogram model D, IBC, decrease,69hours 82

83. Model method Histogram method H Polarization & IBC data C. Morisaki, Master thesis of Osaka university (2009). 83

84. 84

85. Cross Section at E  = 2.0 GeV Vector-meson- dominance model One pion exchange ss knockout uud knockout A.I.Titov et al. Phys. Rev. C58 (1998) 2429 Pomeron exchange is more ten times than anothers Only the Pomeron exchange is clear. The experimental data are from H. J. Besch, G. Hartmann, R. Kose, F. Krautschneider, W. Paul, and U. Trinks, Nucl. Phys. B70, 257 ~1974!. 85

86. LEPS data :LD2 LAB angle  CM angle  86

87. Cancel the systematic error P A   p p 87

88. pp AA (  :+1 p:+1/2)(  :+1 p:-1/2) S=+1 S=+2 S=- 1/2 S=+1 S=-1 S=0 S=+1/2 S=+1 S=0 S=+1 S=-1/2 S=+1 S=0 S=+1 S=+1/2  p p 88

89. Photon beam polarizationCircular polarization Photon beam energyE=1.5-2.4 GeV Photon beam intensity10 6 γ's/sec SpectrometerStandard LEPS magnetic spectrometer Tagger, SC, AC, SVTX, DC1, DC2, DC3, and TOF wall 89

90. θ=0 θ=0.8 θ=0 90

91. Appendix

92. 92

93. 93

94. 94

95. 0212 increase Big rangeSmall range 95

96. 96

97. 97

98. 98

99. 99

100. 100

101.  Magnetic field=17T  Temperature=17mK Cooling power DRS Thermal sensor HD target 101

102.  the Log P Time Empty cell HD 102