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

1. Progress of Polarized Hydrogen-Deuteride (HD) Target for Strangeness Experiments at SPring-8/LEPS Advisors: Rurng-ShengGuo Wen-Chen Chang Graduate: Su-Yin Wang 2009/06/19, NKNU

2. Outline • Introduction • PHYDES01 Production • NMR Measurement • Signal Distortion (Appendix) • Analysis • Result and Conclusion • Discussion and Future

3. Introduction Motivation

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

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

6. Scattering angle LAB angle q CM angle q LEPS data :LD2

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

8. Beam target asymmetrymore sensitive to understand the components of cross section Cancel the systematic error example g P p g A p

9. g p g p S=+1 S=+1 S=+2 S=0 S=+1 S=-1 S=-1/2 S=+1/2 S=-1/2 S=+1/2 S=+1 S=+1 S=+1 S=+1 Cancel Cancel S=0 S=0 S=+1/2 S=-1/2 S=+1/2 S=-1/2 sp: polarization of proton is parallel with polarization of target sA: polarization of proton is anti-parallel with polarization of target

10. Theory Beam-Target double spin asymmetry at Eg = 2.0 GeV Strangeness content is assumed to be 0%(Solid), 0.25%(Dashed), 1%(Dot-dashed). (h0,h1) is the relative phase between the strange and non-strange amplitudes. A.I.Titov et al. Phys. Rev. C58 (1998) 2429

11. Unclear Exchange Particle • 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.

12. Introduction HD Overview

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

14. Small concentrations of ortho-H2 B0

15. Experimental Conditions

16. HD Target at Other Laboratories • At Institut de Physique Nucleaire de Orsay (IPN Orsay) • Magnetic field ~ 15 Tesla • Temperature ~ 10 mK • PH~ 60%, PD~14% • At the Laser Electron Gamma Source (LEGS) at Brookhaven National Laboratory • Magnetic field ~ 15 Tesla • Temperature ~ 15 mK • The initial :PH~ 59%, PD~7% • With Saturated Forbideen Transition (SFT): PH~ 32%, PD~33%

17. HD Target Goal • We can use both proton and neutron. • Temperature ~ 10 mK • Magnetic field ~ 17 Tesla • The target production take 2~3 month. • The target relaxation time ~1 year. • Use the brute force: PH~ 90%, PD~30% • If we use forbidden adiabatic fast passage (FAFP) to invert state polarization. PD can reach to 50%.

18. HD target cell • 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

19. Transport of Polarization HD Target 3 hours 0.5 hours 0.5 hours

20. Main Problems are … Could we succeed in polarization? Could we keep polarization at…

21. Polarized HYdrogen-DEuteride target for Strangeness (PHYDES) PHYDES01 Production

22. HD Purify [H]=1.26% In PHYDES01 [D]=2.07% [HD]=97.66% HD HD Extraction H2 HD D2 HD D2 Extraction

23. Solid HD Production Since TC1 not work now solidify solidify Normal production No TC production

24. PHYDES01 [HD]=97.66%; 0.68 HD was solidified for PHYDES01. After 53 days aging, the relaxation time in three conditions are measured. Time

25. NMR Measurement

26. Principle of NMR Measurement

27. Single coil method

28. Cancellation Circuit Single coil method uses one coil takes both transmitter and receiver coil. Cancellation circuit for keeping away signals which enter in Lock-in Amp at direct without entering in the coil. 14MHz 15MHz 16MHz

29. Flow Chart

30. Polarization Estimate • Polarization signal area • Measure reference signal in thermal equilibrium A

31. Relaxation Time Measurement polarization at thermal equilibrium state polarization decay function combine two function

32. Appendix • Shape Distortion

33. Account of NMR shape width • 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 theinduced current of aluminums wires and cool finger.

34. Non-uniformity of Magnetic Field Magnetic field uniformity profile Measurement value Fitting by 4th-order polynomial Breal ΔB Bcenter ΔB Bcenter

35. Simulation

36. Advanced Simulation • 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.

37. Analysis

38. Analysis outline • 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

39. Preparation of Analysis–Unification of the Signal Amplification The original data with the sensitivity = (1mVrms/-47dBm) The signal is ten times of original one. We also change the signalshape to positive.

40. Preparation of Analysis– Magnetic Field Adjustment B-3 B-2 B-1 B0 B1 B2 B3 ~ B-50 ~ B50 reset

41. Preparation of Analysis– Data Position Shift After Peak Shift

42. Preparation of Analysis– Phase Adjustment • If bad phase … • If good phase … Quadrature Quadrature In Phase In Phase

43. Preparation of Analysis– Remove the Background • Fit each signal only background part • After remove background, for each pulse, start analysis

44. Extracting the Signal Area (Relaxation Time) – Histogram Method • Fit only background part fitting • Fill histogram only signal part (green)

45. Extracting the Signal Area (Relaxation Time) – Histogram Method

46. Extracting the Signal Area (Relaxation Time) –Histogram Method • Fitting example

47. Extracting the Signal Area (Relaxation Time) – Model Method • H model • D model increase increase decrease decrease H:IBC,332hours,θ=0.75 D:IBC,18hours,θ=0.4

48. Extracting the Signal Area (Relaxation Time) – Model Method • Fitting example

49. Extracting the Signal Area (Polarization)– Necessary to Take Average Zoom in each signal Average of “Error of each signal” = 2.05E-3 Error of average signal = 2.72E-4 Signal height ~ 1 .5E-3 Average of 73 signals

50. Extracting the Signal Area (Polarization) – Histogram Method Same as discussed in extracting the signal area of relaxation time