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Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions

Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University). +. g. +. +. +. 3N bound state. Scattering & reactions. +. Discrepancies in 3N systems and their origins. lower energy discrepancies. Ay puzzle 1986. Ay puzzle. ???.

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Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions

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  1. Systematic Experiments on Unsolved Anomalies in 3N breakup Reactions Kenshi Sagara ( Kyushu University)

  2. + g + + + 3N bound state Scattering & reactions +

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

  4. + g + + + 2p3NF confirmed in BE and CS. Complex discrepancies remain in AP’s. Axx~Ayy, Axx anomaly New 3NF at higher energy? + Discrepancies at higher energy Discrepancies at lower energy

  5. 3H binding energy (Theory) (Experiment) 2NF 8.482MeV ~1MeV 2p3NF? 2p3NF has an adjustable parameter. 3H binding energy alone is not the evidence of 2p3NF.

  6. Systematic measurement of pd scattering Ay at Ep =2-18 MeV at KUTL (1994)

  7. E-dependence of Ay puzzle (1994) Discrepancy of -10% ~ -40% Ay puzzle is not related to 2p3NF. Ay puzzle is a puzzle still now.

  8. Energy spectrum of pd scattering Measurement of cross section within 1% accuracy was a hard work.

  9. pd scattering cross section at 2-18 MeV were measured systematically (1994) Exp. errors < 1%. Data were “well” reproduced by 3N calculation. What is the output from this precise experiments?

  10. At the cross section minimum, large discrepancy in relative value was found. (Comapred to Approx.CoulombCalculation) CS discrepancy is comparable to Ay puzzle. But, no one paid attention to this fact ! I appealed this fact to Koike, but Koike did not believe it.

  11. At RIKEN, pd scattering was measured to construct a d-beam polarimeter. N. Sakamoto et al., (1996) The first contribution from SMART pd data from SMART Koike’s nd calculation 30% discrepancy at CS minimum was found also at Ed = 270 MeV. Coulomb effects are small. Koike believe the CS discrepancy.

  12. By Koike’s talk at Few-Body Conf. at KVI (1997), CS minimum discrepancy was widely recognized.

  13. H.Witala et al., Phys Rev Lett. 81 1183(1998) Discrepancy at CS minimum was excellently explained by 2p3NF. The same 2p3NF also reproduces 3N binding energy. Existence of 2p3NF was confirmed (1998), after 41 years since Fujita-Miyazawa theory (1957).

  14. 2p3NF boom from1998

  15. + + g + + + 3NF searches started RIKEN, KVI, RCNP, IUCF,・・ KUTL, RCNP, KVI KUTL, RCNP

  16. K. Sekiguchi et al. Axz Ayd Ayy Axx Ed= 140MeV Ed= 200MeV Ed= 270MeV Pd scattering CS is well reproduced by including 2p3NF, but Polarization observables can not be reproduced by 2p3NF.

  17. + + g + + + Strategy of Kyushu group Search for new 3NF’s other than pp3NF (pr3NF, rr3NF) in pd capture reaction and pd breakup reaction Kyushu G experiments (→new 3NF)

  18. pd capture experiment g + + ○Short-range forces may play important roles. (→new 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

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

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

  21. Data analysis for Axx Y

  22. Data analysis for Ayy & Ay q

  23. 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.) ２NF pd capture at Ed = 200 MeV Calc. by Witala et al. ２NF＋３NF Axx anomaly? Axx~Ayy?

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

  25. We made new experiments (present exp.) at RCNP. Beam : 197 MeV (same as before) Target : Liquid Hydrogen (same as before) Detection: 3He (same as before) Observables: Axx (same as before) Ayy (same as before) Azz (= -Axx-Ayy) (similar to KVI)

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

  27. Axx~Ayy in pd capture Only Ayy measured KVI Ayy & Axx measured Aｘｘ Aｙｙ RCNP Aｙｙ Axx

  28. Why Axx ~ Ayy holds in pd capture? Is it a signal of new 3NF?

  29. Nucl. Phys. A265 280(1976) Nucl. Phys. A334 365(1980) Except for pd capture, Axx~ -Ayy holds in general • Ed=15MeV d-3He breakup • d-α elastic scattering Ayy Ayy Axx Axx Axx Ayy

  30. d-induced reaction in general Axx ~ -Ayy pd capture reaction Axx ~ Ayy <0 Ayy < 0 Ayy > 0 Axx < 0 Axx < 0 Axial symmetry Central region ? Short-range force ? Peripheral region ?

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

  32. pd breakup experiments + + + At Ep = 250 MeV to search new 3NF effects At around Ep = 13 MeV to study Star Anomaly

  33. Ay at 250 MeV relativistic effects 3NF effects

  34. Cross section at 250 MeV K. Hatanaka et al., PRC66 044002(2002) Y. Maeda et al., PRC76 014004(2007) Non-relativistic Relativistic 2NF only 2NF+3NF

  35. Cross Section Cross Section Ratio (Exp/Calc) Cross Section at 250 MeV

  36. Break-up Elastic At 250 MeV, BU cross section is ~5 times larger than elastic scattering cross section

  37. First experiment p1 p2 n Only p1 detected CS at 250 MeV GR Liq D2 Target p - beam LAS p1

  38. p1 p2 n CS at 250 MeV Only p1 detected 2NF+3NF Only 2NF • nd calc.by H. Witala

  39. p1 p2 n CS at 250 MeV Only p1 detected 2NF+3NF Only 2NF • nd calc.by H. Witala

  40. Ay at 250 MeV Only p1 detected 2NF+3NF Only 2NF • nd calc.by H. Witala

  41. We first investigate discrepancy in cross section p1 p2 n Only p1 detected CS at 250 MeV p1 and p2 detected detected p1 free p2 p1

  42. free p2 p1 detected p1 C A B E1 q1-dependence at different E1 B We selected energy B C A q1

  43. free detected p1 detected p2 detected p1

  44. q2-dependence with q1 fixed at15 degree and F12 = 180 degree 2NF+3NF 2NF Calc by H. Kamada q1 F12 q1 F12-dependence with q1 and q2 fixed at15 degree and 35 degree F12

  45. q2-dependence with q1 fixed at15 degree and F12 = 180 degree 2NF+3NF 2NF Calc by H. Kamada q1 F12 q1 F12-dependence with q1 and q2 fixed at15 degree and 35 degree F12

  46. p1 p2 n CS at 250 MeV p1 and p2 detected p2 GR Liq D2 Target p - beam LAS p1

  47. p2 p1 n GR VDC + DE scintillator Momentum accept.：2.5% • GRとLASの相対角度の最小値は約50o D(p,p1p2)n CS at 250 MeV p1 and p2 detected Liq D2 Target Unpolarized p-beam • LAS • VDC + DE scintillator • Momentum accept.：2.5% • GRとLASの相対角度の最小値は約50o

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