Recent experiments on three nucleon systems and problems to be solved

1. FB19 Recent experiments on three nucleon systems and problems to be solved Kenshi Sagara Kyushu U. , Fukuoka, Japan

2. + g + + + Experiments in Nd system Basic process High momentum transfer + Various configurations QFS, FSI, Star, Collinear, .. Calculatons with 2NF+3NF 3-nucleon forces 3-body effects Systematic experiments +

3. Discrepancies in 3N systems and their origins -- lower energy discrepancies -- Ay puzzle 1986 Systematic measurements ??? Ay puzzle -- higher energy discrepancies -- pd sactt. discrepancy 3N BE problem 1980’s FM-3NF 1957 pp3NF(FM) was found 1998 pr3NF? rr3NF? relativity? pd breakup discrepancy pd CS discrepancy 1994-1996-1997 (Sagara discrepancy) Faddeev eqs. 1960 pd capture Ajj anomaly -- lower energy discrepancies -- Off-plane Sar anomaly QFS anomaly Space Star anomaly 1989 ??? We are here.

4. + + Ay puzzle Ay at EN =5-18 MeV (~1994)

5. nd Ay & pd Ay EN=10MeV pd Ay Ep=22.7MeV A suggestion to solve Ay puzzle Modified calculations Original calculation Modification factors H. Witala and W. Gloeckle, NPA528 (1991)48

6. Modification of LS force in 2NF Modification of 3PJ forces in 2NF Addition of LS force in 3NF Adjusting of forces in cPT Ay puzzle Origin(s) 3NF effects? Relativistic effects? or ……….. Ay puzzle is a long-standing problem since 1986 (FB11).

7. Shortage of 3H binding energy (1980’s) (Theory) (Experiment) 2NF 8.482MeV ~1MeV shortage 3H B.E. can be reproduced by adjusting a parameter L in 2p3NF Another evidence was necessary to confirm 2p3NF

8. + + Systematic measurement of pd scattering cross section (1994) 5MeV 12MeV 10MeV 18MeV Here are discrepancies

9. + + pd cross section (RIKEN 1996) 30% difference nd calculation by Koike

10. + + Koike’s talk at FB15 (KVI) RIKEN data (1996) Kyushu data (1994)

11. + + Scattering cross section Binding energy 2NF 8.482MeV (exp.) 2p3NF 2p3NF H.Witala et al., Phys Rev Lett. 81 1183(1998) 41 years 2p3NF was found (1998) Fujita-Miyazawa (1957)

12. Discrepancies in 3N systems and their origins -- lower energy discrepancies -- Ay puzzle 1986 Systematic measurements ??? Ay puzzle -- higher energy discrepancies -- pd sactt. discrepancy 3N BE problem 1980’s FM-3NF 1957 pp3NF(FM) was found 1998 pr3NF? rr3NF? relativity? pd breakup discrepancy Faddeev eqs. 1960 pd CS discrepancy 1994-1996-1997 (Sagara discrepancy) pd capture Ajj anomaly -- lower energy discrepancies -- Off-plane Sar anomaly QFS anomaly Space Star anomaly 1989 ??? We are here.

13. g + + pd capture experiment ○high momentum transfer → short-range 3NF ×Reaction cross section is very small (< 1 m barn). • Experimental techniques • thick target & low BG 　　→　liquid hydrogen target • high-efficiency detection → one-shot measurement of whole • angular distribution

14. Side View (enlargement) Front View f12 Liquid Hydrogen Target 精密実験に不可欠 mm

16. q(3He) < 4.7 Vertical plane for Axx Horizontal plane for Ayy & Ay Whole angular distribution was measured in one shot.

17. BG level was low Y

18. 0.2 0.2 0.0 0.0 Ayy Axx -0.2 -0.2 -0.4 -0.4 -0.6 0 50 100 150 0 50 100 150 C.M angle (deg.) C.M angle (deg.) 0.2 0.5 0.4 0.1 0.3 Crosssection (mb/sr) Ay 0.0 0.2 -0.1 0.1 -0.2 0.0 0 50 100 150 0 50 100 150 C.M angle (deg.) C.M angle (deg.) Axx anomaly in pd capture at Ed = 200 MeV from RCNP exp. (Yagita et al. 2002) ２NF Calc. by Witala et al. ２NF＋３NF Axx anomaly? Axx~Ayy?

19. Ajj of pd-capture were measured also at KVI, and KVI data agreed with calculations. Axx Ayy ● ○RCNP(200MeV) ■ □KVI 　（180MeV) Azz RCNP data at 137MeV also disagreed with KVI data at 133MeV.

20. Experiment at KVI, Ayy & “Azz”(=-Axx-Ayy ) Big-Bite spectrometer (BBS) & Plastic Ball detector (PB) g-detection Azz :45±10 degree Ayy : 0±15 dergree Azz= -Axx-Ayy Beam axis

21. Re-measurement at RCNP at 200 MeV d +p→3He+g Ed =200 MeV q(3He) < 4.7deg Slit in front of LAS Beam polarization is along y-axis. “Azz ”= (Axx-Ayy) Ayy Axx

22. Background subtraction y polarized beam True Liuqid target BG y unpol. beam Empty target

23. Detection efficiency

24. Backgroun estimation was much improved by a multi-II method. X1 Single cluster ~83% X2 Efficiency =.834 =0.48 Standard data analysis X1 Multiple cluster ~14% X2 Efficiency =.974 =0.88 X1 Overlapped cluster & single cluster ~2% X2 Efficiency =.994 =0.96 Multi-II data analysis X1 Overlapped–overlapped cluster Other rays ~1% X2 Total 100%

25. Single cluster data analysis vs. Multi-cluster II data analysis (new) 2002 exp.

26. d+p→3He+g New data and previous data (new multi-II analysis) present 2002

27. d+p→3He+g New data and previous data (Multi-II) present 2002 “Azz” -(Axx+Ayy) -(Axx+Ayy)

29. pd radiative capture at Ed = 137 MeV (multi-II analysis)

30. g + + Ajj in pd capture Axx anomaly (Azz anomaly) has been confirmed. Axx ~ Ayy ---> axial symmetry ? Azz > calculation ----> short range reaction?

31. + + pd scattering CS at 250 MeV E-dependence of CS at 150 degree exp/cal at q = 150⁰ 2p3NF q=150⁰

32. J. Kuros-Zoluierczuk et al., PRC66, 024003 (2002).

33. + + + D(p,pp)n CS at 250 MeV

34. + + + Inclusive exp. at 250 MeV D(p,p)pn experiment (global feature) un-detected p d p detected Exclusive exp. at 250 MeV D(p,pp)n experiment (microscopic study) p detected p d p detected --> Kuroita’s talk

35. + + + + + pd & nd scattering CS above 150 MeV pd breakup CS at 250 MeV, inclusive & exclusive Short-range 3NF? Relativity? ……..? Large (~2 times) CS enhancement

36. + + + Space star anomaly around 10 MeV

37. α=144º α=124º

38. + + + QFS anomaly? ～QFS ～QFS En Is there QFS anomaly in addition to space star anomaly?

39. Result (pp-QFS) Ep= 13 MeV Ep= 9.5 MeV star QFS QFS ~7% smaller ~9% smaller preliminary preliminary

40. Ep= 9.5 MeV Ep= 13 MeV pd QFS

41. + θ1= θ2= 42 deg. ～18% nd QFS A. Siepe et al., Phys. Rev. C 65, 034010 (2002) θ1= θ2= 42.2 deg. + + ～16% pd QFS X. C. Ruan et al., Phys. Rev. C 75, 057001 (2007) Also there are nd QFS (2002,2007), and CS of nd QFS is higher than calculation, CS of pd QFS is lower than calculation.

42. Angular dependence of QFS anomaly Ep= 9.5 MeV ① ② ③ ⑦ ⑥ ⑤ ④ Ep= 13 MeV 1 2 3 4 7 6 5

43. Nd breakup cross section at low energy Star anomaly Star anomaly appears only around space star (a = 90 °) at 13 MeV, and in a wide angular region at 9.5MeV. Large CSB occurs, nd CS> calc, and pd CS < calc. What origin(s) Same origin or different ones? QFS anomaly CS anomaly also appears in pd QFS and nd QFS. QFS anomaly appear s in a wide angular region. Large CSB occurs, nd CS> calc, and pd CS < calc.

44. Discrepancies in 3N systems and their origins -- lower energy discrepancies -- Ay puzzle 1986 Systematic measurements ??? Ay puzzle -- higher energy discrepancies -- pd sactt. discrepancy 3N BE problem 1980’s FM-3NF 1957 pp3NF(FM) was found 1998 pr3NF? rr3NF? relativity? pd breakup discrepancy Faddeev eqs. 1960 pd CS discrepancy 1994-1996-1997 (Sagara discrepancy) pd capture Ajj anomaly -- lower energy discrepancies -- Off-plane Sar anomaly QFS anomaly Space Star anomaly 1989 ??? We are here.

45. More systematic experiments on some reactions + More challenging calculations with new 3NF, new frame, … remaining 3NF’s unknown 3-body effects …….