• Tuesday 8 June 2021 at 10:15 with Zoom: Kenneth Österberg (Helsinki)
    Observation of odderon exchange from proton-proton and proton-antiproton elastic scattering at TeV scale
    Abstract: In addition to the dominant C-even gluonic exchanges, may C-odd gluonic exchanges (“odderon”) occur in high energy elastic hadron scattering.  Contrary to C-even exchanges, C-odd exchanges are not invariant for proton-proton (pp) and proton-antiproton (ppbar) scattering. Therefore,  any significant difference in the elastic pp and ppbar cross section at the same energy at TeV scale, where gluonic exchanges are dominant, would be evidence for C-odd exchanges. We make a model-independent extrapolation of the TOTEM 2.76, 7, 8, and 13 TeV pp elastic cross sections to 1.96 TeV. We observe a difference with a 3.4σ significance between the extrapolated pp elastic cross section and the D0 ppbar elastic cross section at 1.96 TeV in the region of the diffractive minimum and the second maximum of the pp cross section. We combine these results with a TOTEM analysis of the same C-odd exchange based on forward pp elastic scattering at TeV scale. The combined significance is larger than 5σ and is interpreted as the first observation of the exchange of an odderon.

Hopefully the up to 50 min + 10 min discussion long seminar/colloquium will be understandable to a wide audience.
Contacts: Keijo Kajantie (keijo kajantie at helsinki fi) [ HIP seminar],
Sami Raatikainen (sami raatikainen at helsinki fi) [cosmo seminar]

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Other related seminars

Friday 10-12 seminar series in A315:Astrophysics seminar.
Mathematical Physics Seminar and Workshop series Wed 14-16 in Exactum C123.