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On the difference between pp and ppbar cross sections

On the difference between pp and ppbar cross sections. Yoshitaka Hatta (U. Tsukuba). JHEP 1003:037 (2010); 0912.3806 [hep-th] with Emil Avsar and Toshihiro Matsuo. The total cross section difference. Consider the difference. What’s the fate of as ?.

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On the difference between pp and ppbar cross sections

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  1. On the difference between pp and ppbar cross sections Yoshitaka Hatta (U. Tsukuba) JHEP 1003:037 (2010); 0912.3806 [hep-th] with Emil Avsar and Toshihiro Matsuo

  2. The total cross section difference Consider the difference What’s the fate of as ? Tevatron ( ) ISR ( ) Up to the ISR energy, LHC( ), cosmic rays

  3. First data from LHC Discrepancy between the data and MC tuned to Tevatron and CERN data

  4. Odderon and Reggeon The difference is odd under crossing, generated by the exchange of C-odd objects in QCD Reggeon (vector mesons) Odderon (C-odd glueballs) Lukaszuk, Nicolescu (1973) Attributed to the Reggeon exchange. Any room for the Odderon?

  5. The AdS/CFT correspondence Maldacena (1997) Conjecture: N=4 SYM at strong coupling is dual to type IIB at weak coupling on our universe extra dimensions N=4 SYM string (anomalous) dimension mass `t Hooft parameter curvature radius number of colors string coupling constant

  6. High energy scattering in AdS Regge trajectory in string theory graviton, dilaton, SO(6) gauge boson, B-field…. Reggeized graviton = Pomeron Total cross section  Total cross section difference  Reggeized B-field = Odderon Brower, Djuric, Tan (2009)

  7. compactify on “diagonal” “off-diagonal” dual “Reggeon” “Odderon” Odderon and Reggeon unified in 10 dimensions The antisymmetric B-field 10D B-field

  8. Baryons in AdS/CFT our universe, at . strings D5-brane wrapping on Imamura (1999) Callan, Guijosa, Savvidy (1999) Witten (1998)

  9. Baryon-Odderon coupling Born-Infeld and Chern-Simons action Reggeon Odderon (decouple) Odderon amplitude, fixed impact parameter

  10. B-field propagator Bena, Nastase, Vaman (2001) “chordal distance” Up to this point, the amplitude is purely real.

  11. Analytic continuation in spin Include higher spin string excited states. Analytically continue the B-field propagator to and sum over A cut beginning at

  12. Note that is negative ! …in conflict with the ISR data… Total cross section difference Odderon intercept

  13. exchange of the B-field  repulsion  However, this may not be true in a curved space ! Look at the tensor part of the B-field propagator positive if the derivatives act on the numerator negative if the derivatives act on the denominator How can be negative? sign of  sign of  sign of the interaction

  14. Sign flip from the warp factor negative positive (expected) The negative contribution is enhanced after integrating over , dominates over the positive contribution when Attraction between like charges and repulsion between opposite charges ! due to the curvature of AdS.

  15. A scenario (“prediction”) Reggeon gives a positive contribution Odderon gives a negative contribution when At the ISR energies, the Reggeon dominates. But the Odderon eventually flips the sign of , possibly at the LHC!

  16. A recent prediction Extrapolate the low-energy phenomenological fit to high energies. Avila, Gauron, Nicolescu (2007) Negative !

  17. An old prediction In the very first paper in 1973, they have predicted !!

  18. A hint from LHC? Need to produce more particles in pp !

  19. Conclusion • Single-odderon exchange between “baryons” calculated from AdS/CFT • Analytical expression of the total cross section difference. • The pp cross section becomes larger than the ppbar cross section at very high energies, possibly at the LHC.

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