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What have we learned about three-nucleon systems at intermediate energies?

What have we learned about three-nucleon systems at intermediate energies?. Nasser Kalantar-Nayestanaki Kernfysisch Versneller Instituut (KVI), Univ. Of Groningen 18th International Symposium on Spin Physics (SPIN 2008) Charlottesville, Virginia, October 6, 2008. Nijmegen I Nijmegen II

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What have we learned about three-nucleon systems at intermediate energies?

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  1. What have we learned about three-nucleon systems at intermediate energies? Nasser Kalantar-Nayestanaki Kernfysisch Versneller Instituut (KVI), Univ. Of Groningen 18th International Symposium on Spin Physics (SPIN 2008) Charlottesville, Virginia, October 6, 2008

  2. Nijmegen I • Nijmegen II • Reid 93 • CD-Bonn • Argonne V18 • … N-N Potentials Modern phenomenological NN potentials: Comparison with experimental np&pp database gives: 2/data ~ 1

  3. Ab-initio Calculations for Nuclei S. Pieper et al., Argonne (2NF) (+3NF)

  4. Three-Nucleon Force! (3NF) Phenomenological N-N forces fail to describe A>2 systems! How to resolve? Beyond phenomenological N-N forces

  5. “...the replacement of field interactions by two-body action-at-a-distance potentials is a poor approximation in nuclear problems.” Three-Body Forces in Nuclear Physics

  6. Three-Body Forces in Nuclear Physics N N  N

  7. Ggggggg p D p p p Three-Body Forces in Nuclear Physics • parametrization of Fuijta-Miyazawa force + 2p rescattering + higher-order interactions • Added to 2N potential as correction • Tucson-Melbourne, Urbana IX, IL2, Brazil, ...

  8. Effective-Field Theory Approach • Developed by Weinberg • Coupling of pions and nucleons in EFT • Predicts structure of 3NF • Self-consistent approach • Only works at energies below pion-mass scale

  9. Three-body forces and Wikipedia A three-body force is a force that does not exist in a system of two objects but appears in a system of three objects (three-body system like in Euler's three-body problem) or more. In physics, an intuitive example of a three-body force is the case of charged, metallic spheres: the charge distribution at the surface of two spheres placed close to each other will be modified, and thus the total force felt by a third sphere cannot be described by the sum of the forces from the two other spheres taken individually. The fundamental strong interaction seems to exhibits such behaviours. In particle physics, the interactions between the three quarks that compose baryons can be described in a diquark model which is equivalent to the hypothesis of a three-body force. There is growing evidence in the field of nuclear physics that three-body forces exist among the nucleons inside atomic nuclei (three-nucleon force). As an analogy, if we identify bodies with human beings and forces with emotions, jealousy is a good example of three-body force: it is not felt as long as only two persons are acting, but it can show up as soon as a third person enters into the scene. Retrieved from "http://en.wikipedia.org/wiki/Three-body_force"

  10. ndscattering np scattering Only 2NF Total nd Cross sections • Effect of 3NF small • High-precision mandatory • In addition, look for sensitivity: • exclusive channels • other observables High precision data from Los Alamos W.P. Abfalterer et al., PRL 81, 57 (1998)

  11. The Smoking Guns s2NF+3NF – s2NF Ds = s2NF+3NF p+d  p+p+n (190 MeV) • Elastic N+d scattering: at the minimum of the cross section and towards higher energies • Three-nucleon break-up: more degrees of freedom • Four-nucleon scattering: larger sensitivity to 3NFs

  12. 5 MeV 7 MeV 9 MeV 2+3NF 2NF 10 MeV 12 MeV 16 MeV 22.7 MeV 28 MeV The Ay puzzle at low energies 18 MeV Calculations by Pisa group

  13. The Ay puzzle at low energies Calculations by Pisa group, data courtesy T. Clegg from TUNL

  14. AGOR Facility

  15. Few-Nucleon Studies @ KVI BBS PB SALAD 1995-2002 BINA 2004-??? • ppg/pdg • d+p breakup • p+d3He+g(*) • d+d scattering (2B,3B) • pd+dp elastic • d+p3He+g(*) • d+d scattering (2B)

  16. p+d vector analyzing powers Bieber et al., PRL84, 606 (2000) Ermisch et al., PRL86, 5862 (2001) PRC71, 064004 (2005)

  17. p+d vector analyzing powers Bieber et al., PRL84, 606 (2000) Ermisch et al., PRL86, 5862 (2001) PRC71, 064004 (2005)

  18. p+d vector analyzing powers Bieber et al., PRL84, 606 (2000) Ermisch et al., PRL86, 5862 (2001) PRC71, 064004 (2005)

  19. p+d vector analyzing powers Bieber et al., PRL84, 606 (2000) Ermisch et al., PRL86, 5862 (2001) PRC71, 064004 (2005)

  20. p+d vector analyzing powers Bieber et al., PRL84, 606 (2000) Ermisch et al., PRL86, 5862 (2001) PRC71, 064004 (2005)

  21. p+d vector analyzing powers Bieber et al., PRL84, 606 (2000) Ermisch et al., PRL86, 5862 (2001) PRC71, 064004 (2005)

  22. p+d vector analyzing powers theory-data Bieber et al., PRL84, 606 (2000) Ermisch et al., PRL86, 5862 (2001) PRC71, 064004 (2005)

  23. p+d vector analyzing powers theory-data Bieber et al., PRL84, 606 (2000) Ermisch et al., PRL86, 5862 (2001) PRC71, 064004 (2005)

  24. p+d vector analyzing powers Hanover Approach of dynamical delta theory-data Bieber et al., PRL84, 606 (2000) Ermisch et al., PRL86, 5862 (2001) PRC71, 064004 (2005)

  25. Effect of 3NF as a function of Energy Bieber et al., PRL84, 606 (2000) Ermisch et al., PRL86, 5862 (2001) PRC68, 054004(2003) PRC71, 064004(2005)

  26. Spin-Transfer Coefficients

  27. Spin-Transfer Coefficients H.R. Amir-Ahmadi et al., PRC 75, 041001(R) 2007

  28. Spin-Transfer Coefficients H.R. Amir-Ahmadi et al., PRC 75, 041001(R) 2007

  29. Spin-Transfer Coefficients H.R. Amir-Ahmadi et al., PRC 75, 041001(R) 2007

  30. Spin-Transfer Coefficients H.R. Amir-Ahmadi et al., PRC 75, 041001(R) 2007

  31. Spin-Transfer Coefficients H.R. Amir-Ahmadi et al., PRC 75, 041001(R) 2007

  32. Spin-Transfer Coefficients Hanover Approach of dynamical delta H.R. Amir-Ahmadi et al., PRC 75, 041001(R) 2007

  33. Spin-Transfer Coefficients H.R. Amir-Ahmadi et al., PRC 75, 041001(R) 2007

  34. More analyzing powers 65 MeV/A 90 MeV/A H. Mardanpour et al., Eur. Phys. J. A31, 383 (2007)

  35. Break-up channel 5 dimensional phase space (1, 2, E1, E2, 12) i.e. much larger than in the elastic channel () Allows detailed road-map for the study of nuclear forces Requires a setup with large coverage

  36. Break-up channel at 65 MeV/A Kistryn et al., Phys. Lett. B 641, 23 (2006) Analysis by Polish group S (MeV)

  37. CDBonn  Ay p+dp+p+n @ 135 MeV/A Cross sections and analyzing powers in p+d breakup at 135 MeV with BINA Note: only a few of the many measured configurations are shown PRELIMINARY Thesis, M. Eslami-Kalantari

  38. CDBonn  Ay CDBonn+TM’ CDBonn+ p+dp+p+n @ 135 MeV/A Significant discrepancies in  and Ay (but not simultaneous) Ay puzzle at small relative energies?!? The Nd scattering process at 135 MeV cannot be described consistently yet PRELIMINARY Thesis, M. Eslami-Kalantari

  39. p+dp+p+n @ 190 MeV/A Preliminary Discrepancies confirmed and larger at 190 MeV Small relative energy between the protons Mardanpour et al., PhD thesis, in preparation for publication

  40. p+dpp(1S0)+n @ 190 MeV/A p+dd+p p+d2He+n CDBonn+ CDBonn Mardanpour, PhD thesis, in preparation for publication

  41. dd elastic scattering at 65 MeV/A Data: BINA: A. Ramazani et al. BBS: C. Baily et al. Calculation: Deltuva, Fonseca Note: calculation based on Born Approximation (not expected to make reliable predictions at this energies) A. Ramazani, Ph.D. thesis

  42. First experiments for the break-up very successful. • Results available for observables from 50 to 190 Mev/A. Breakup Summary • Three-body hadronic reactions are the most promosing tool for the study of 3BF effects. • A systematic study of cross sections and analyzing powers as a function of energy provides a good data-base for these studies. • Aside from cross sections, many spin observables have also been studied at various energies. Elastic Scattering

  43. Outlook • The search for 3BF effects at intermediate energies is coming to an end. • At KVI, our comprehensive program to study the three-body systems will come to an end in 2009. • The situation for the three-body systems is like the situation of NN of some 20 years ago! PWA is desperately called for. • The 4-body system is coming up. • The theoretical progress in 4-body systems is very promising. The first ab-initio calculations are available below 3B breakup and demonstrate the high sensitivity to “physics” beyond what is known.

  44. Acknowledgements H.R. Amir Ahmadi, A.M. van den Berg, R. Bieber, K. Ermisch, M. Elsami-Kalantari, M.N. Harakeh, H. Huisman, M. Kis, H. Mardanpour, A. Mehmandoost, J.G. Messchendorp, M. Mahjour-Shafiei, A. Ramazani, E. Van Garderen, M. Volkerts, S.Y. van der Werf, H. Woertche + Polish Experimental Group (O. Biegun, K. Bodek, St. Kistryn, A. Kozela, A. Magiera, A. Micherdzinska, E. Stephan, R. Sworst, J. Zejma and W. Zipper) + Tokyo group (K. Itoh, T. Kawabata, H. Kuboki, Y. Maeda, S. Sakaguchi, H. Sakai, N. Sakalmoto, Y. Sasamoto, M. Sasano, K. Sekiguchi, K. Suda, Y. Takahashi, T. Uesaka, K. Yako + Bloomington group (C. Bailey, A. Bacher, A. Micherdzinska and E. Stephenson) + Theoretical support from Bochum-Cracow (Gloeckle, Golak, Kuros-Zolnierczuk, Skibinski and Witala) KIT (Kamada) Hanover (Sauer) Lisbon (Deltuva, Fonseca) Jülich (Epelbaum, Nogga)

  45. The new polarimeter and the 4 detector, BINA BINA @ KVI ~3 meters beam Big Instrument for Nuclear-polarization Analysis (BINA)

  46. Wire chambers + analyzer 150 phoswich Scintillators =Target chamber Thin scintillators for particle identification Forward scintillators (E-wall) The new polarimeter and the 4 detector, BINA

  47. The new Polarimeter and the 4 detector

  48. Effect of 3NF as a function of Mandelstam t

  49. Effect of 3NF as a function of Mandelstam t

  50. Effect of 3NF as a function of Mandelstam u

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