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Threshold resummation in hadronic scattering. Werner Vogelsang Univ. Tübingen Bloomington, 12/13/2013. Daniele’s talk: R esummation in SIDIS & e + e - annihilation . Color singlet hard LO scattering . Natural connection to Drell -Yan and .
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Threshold resummation in hadronic scattering Werner Vogelsang Univ. Tübingen Bloomington, 12/13/2013
Daniele’s talk: Resummation in SIDIS & e+e- annihilation Color singlet hard LO scattering Natural connection to Drell-Yan and Now: processes with underlying QCD hard scattering: Insights into fragm. fcts. / nucleon structure Test / improve our understanding of QCD at high energies
Pair-invariant mass (PIM) kinematics: pair mass2 “like” Drell-Yan • One-particle inclusive (1PI) kinematics:
PIM: Define with partonic variables
LO: cfDrell-Yan
Beyond LO: true to all orders! e.g. NLO: at kth order: threshold logs
1PI: mass2 partonicvariables:
LO: Beyond LO: not necessarily soft ! at kth order:
logs due to soft / collinear emission resummation achieved in Mellin-moment space: PIM: Likewise, 1PI: moments
soft & coll. gluons large-angle soft
like Drell-Yan matrix problem in color space: Kidonakis,Oderda,Sterman Bonciani,Catani,Mangano,Nason Almeida,Sterman,WV
Compare leading logarithms (MS): PIM: 1PI:
Resummation for pp h1 h2 X L. Almeida, G.Sterman, WV
Resummation for p h X (at COMPASS) D.de Florian, M.Pfeuffer, A.Schäfer, WV
Resummation for pp jet X D.de Florian, P.Hinderer, A.Mukherjee, F.Ringer, WV
? recall, 1PI:
Threshold logarithms depend crucially on treatment of jet: Kidonakis, Sterman LO: jet massless (1) keep jet massless at threshold: no dependence on R Kidonakis, Owens; Moch, Kumar (2) jet allowed to be massive at threshold:
LHC K Moch, Kumar (arXiv:1309.5311)
Full (analytical) NLO calculation for “narrow jets” Jäger, Stratmann, WV; Mukherjee, WV …allows to pin down behavior near threshold: confirms that (2) is right de Florian, WV; de Florian, Hinderer, Mukherjee, Ringer, WV arXiv:1310.7192
NNLO corrections in all-gluon channel: Currie, Gehrmann-De Ridder, Glover, Pires, arXiv:1310.3993
Conclusions: •significant resummation effects in hadronic scattering: PIM / 1PI kinematics •predictions from resummation formalism as benchmark for full NNLO calculations
Gehrmann-De Ridder, Gehrmann, Glover, Pires, arXiv:1301.7310
Eventually, inverse Mellin / Fourier transform: “Minimal prescription” Catani,Mangano,Nason,Trentadue “Matching” to NLO: