Few-body physics: Three-body force effects

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Few-body physics Three-body force effects

• Nasser Kalantar-Nayestanaki
• Kernfysisch Versneller Instituut
• Groningen
• November 18, 2005

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Bound-state energies with GFMC
Courtesy S. Pieper, Argonne
(3NF)
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Few-body activities at KVI

• Study of the nucleon-nucleon interaction beyond
  the elastic scattering
• Real-photon bremsstrahlung
• Virtual-photon bremsstrahlung
• Study of three-body systems
• Hadronic probes (three-body force effects)
• Electromagnetic probes
• Study of strangeness in proton and deuteron

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Binding Energies in 3H 4He
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Three-Body Forces in Nature
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Three-Body Forces in Nature
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Three-body forces in Nuclear physics
?
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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"
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Total nd Cross sections
Only 2NF

• High precision data from Los Alamos
• W.P. Abfalterer et al., PRL 81, 57 (1998)

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Nd elastic scattering cross sections
Enlab 140 MeV
Enlab 12 MeV
3NF only
2NF only
Enlab 65 MeV
Enlab 200 MeV

• H. Witala et al. PRL 81, 1183 (1998)

Total
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AGOR Facility
Detectors
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pd elastic scattering cross sections
K. Ermisch et al., PRC 68, 054004 (2003), PRC
71, 064004 (2005)
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pd elastic scattering cross sections
K. Ermisch et al., PRC 68, 054004 (2003), PRC
71, 064004 (2005)
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pd elastic scattering cross sections
K. Ermisch et al., PRC 68, 054004 (2003), PRC
71, 064004 (2005)
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pd elastic scattering cross sections
K. Ermisch et al., PRC 68, 054004 (2003), PRC
71, 064004 (2005)
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pd elastic scattering cross sections
K. Ermisch et al., PRC 68, 054004 (2003), PRC
71, 064004 (2005)
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pd elastic scattering cross sections
K. Ermisch et al., PRC 68, 054004 (2003), PRC
71, 064004 (2005)
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pd elastic scattering cross sections
(theory data)/data
K. Ermisch et al., PRC 68, 054004 (2003), PRC
71, 064004 (2005)
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pd elastic scattering cross sections
(theory data)/data
K. Ermisch et al., PRC 68, 054004 (2003), PRC
71, 064004 (2005)
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pd elastic scattering cross sections
(theory data)/data
Hanover Approach of dynamical delta
K. Ermisch et al., PRC 68, 054004 (2003), PRC
71, 064004 (2005)
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Effect of 3NF as a function of Energy
Ermisch et al., PRC71, 064004 (2005)
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Spin-Transfer Coefficients
_at_ Ed 180 MeV
Preliminary results
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The break-up channel
St. Kistryn, PRC 68, 054004 (2003) PRC
72, 044006 (2005)
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The break-up channel
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The new 4? detector, BINA
BINA _at_ KVI
3 meters
beam
Big Instrument for Nuclear-polarization Analysis
(BINA)
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The new 4? detector, BINA
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The new 4? detector, BINA
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Summary Outlook

• The search for 3BF effects is taking place at
  several laboratories.
• At KVI, we have set up a comprehensive program to
  study the three-body systems.
• The situation for the three-body systems is like
  the situation of NN of some 30 years ago!
• The four-body systems is virgin territory at this
  moment and needs desperate attention.

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Acknowledgements
H.R. Amir Ahmadi, J.C.S. Bacelar, R. Benard, A.M.
van den Berg, R. Castelijns, M. Eslami-Kalantari,
R. Bieber, K. Ermisch, E. Van Garderen, V.M.
Hannen, M.N. Harakeh, M. de Huu, H. Huisman, M.
Kis, H. Löhner, H. Mardanpour, A. Mehmandoost,
J.G. Messchendorp, M. Mahjour-Shafiei, A.
Ramazani, S. Schadmand, S. Shende, M. Volkerts,
S.Y. van der Werf, H. Wörtche KVI theory
group Cracow Experimental Group Theoretical
support from Bochum-Cracow Hannover group
TAPS collaboration