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Diffraction from CDF2LHC. K. Goulianos Tev4LHC 3-5 February 2005 Brookhaven National Laboratory. * * * * * *. H He. M. E. What is Dark Energy?. * * * * * *. H He. M. E. Diffractive interactions. Rapidity gaps at t=0 grow with D y. 2 e : negative particle density!.
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Diffraction from CDF2LHC K. Goulianos Tev4LHC 3-5 February 2005 Brookhaven National Laboratory Diffraction from CDF2LHC K. Goulianos
* * * * * * H He M E What is Dark Energy? * * * * * * H He M E Diffraction from CDF2LHC K. Goulianos
Diffractive interactions Rapidity gaps at t=0 grow with Dy. 2e: negative particle density! Rapidity Gaps Bj, PRD 47 (1993) 101: regions of (pdeudo)rapidity devoid of particles Non-diffractive interactions Rapidity gaps are formed by multiplicity fluctuations. From Poisson statistics: (r=particle density in rapidity space) Gaps are exponentially suppressed Diffraction from CDF2LHC K. Goulianos
CDF Run I results http://physics.rockefeller.edu/dino/my.html 93(2004)141601 Diffraction from CDF2LHC K. Goulianos
p p valence quarks antiproton antiproton SOFT HARD eg=0.20 lg=0.5 eq=0. 04 lq=0.3 eR=-0.5 Single Diffraction deep sea valence quarks Derive diffractive from inclusive PDFs and color factors x=x proton Diffraction from CDF2LHC K. Goulianos
Inclusive Single Diffraction • Unitarity problem: Using factorization and std pomeron flux sSD exceeds sT at • Renormalization: normalize the Pomeron flux to unity KG, PLB 358 (1995) 379 Diffraction from CDF2LHC K. Goulianos
A Scaling Law in Diffraction KG&JM, PRD 59 (1999) 114017 Factorization breaks down in favor of M2-scaling renormalization 1 Diffraction from CDF2LHC K. Goulianos
QCD expectations f y The exponential rise of sT(Dy’) is due to the increase of wee partons with Dy’ (see E. Levin, An Introduction to Pomerons,Preprint DESY 98-120) f y Elastic and Total Cross Sections Total cross section: power law rise with energy ~1/as Elastic cross section: forward scattering amplitude Diffraction from CDF2LHC K. Goulianos
color factor Renormalization removes the s-dependence SCALING Soft Diffraction (KG, hep-ph/0205141) t 2 independent variables: gap probability sub-energy x-section Diffraction from CDF2LHC K. Goulianos
Color factor: Pomeron intercept: lg=0.20 lq=0.04 lR=-0.5 The Factors k and e Experimentally: KG&JM, PRD 59 (114017) 1999 CTEQ5L fg=gluon fraction fq=quark fraction Diffraction from CDF2LHC K. Goulianos
5 independent variables color factors Gap probability Sub-energy cross section (for regions with particles) Multigap Diffraction (KG, hep-ph/0205141) Same suppression as for single gap! Diffraction from CDF2LHC K. Goulianos
Differential shapes agree with Regge predictions DD SDD DPE Central and Two-Gap CDF Results • One-gap cross sections are suppressed • Two-gap/one-gap ratios are Diffraction from CDF2LHC K. Goulianos
S = Gap Survival Probability Results similar to predictions by: Gotsman-Levin-Maor Kaidalov-Khoze-Martin-Ryskin Soft color interactions Diffraction from CDF2LHC K. Goulianos
p x,t jet IP x g* p e g* Q2 e reorganize Diffractive DIS @ HERA Factorization holds: J. Collins Pomeron exchange Color reorganization Diffraction from CDF2LHC K. Goulianos
F2 ~ x-l aP(0)-1 (eq+l)/2 eq Inclusive vs Diffractive DIS KG, “Diffraction: a New Approach,” J.Phys.G26:716-720,2000 e-Print Archive: hep-ph/0001092 Diffraction from CDF2LHC K. Goulianos
At fixed x: flat Q2-dependence At fixed Q2: flat x-dependence sdiff/sincl DIS at HERA Diffraction from CDF2LHC K. Goulianos
jet p jet reorganize Diffractive Dijets @ Tevatron Diffraction from CDF2LHC K. Goulianos
FDJJ(x,b,Q2) @ Tevatron Diffraction from CDF2LHC K. Goulianos
SD/ND Dijet Ratio vs xBj@ CDF 0.035 < x < 0.095 Flat x dependence Diffraction from CDF2LHC K. Goulianos
p x,t IP IP IP p p p p g* H1 e CDF gap gap dN/dh dN/dh Tevatron vs HERA:Factorization Breakdown Predicted in KG, PLB 358 (1995) 379 Diffraction from CDF2LHC K. Goulianos
M. Arneodo, HERA/LHC workshop, CERN, 11-13 Oct 2004 ZEUS Fit including charm data H1 Fit without charm data Flat after subtracting Reggeon contribution New: FDJJ(b) from ZEUS-LPS Data Diffraction from CDF2LHC K. Goulianos
R(SD/ND) R(DPE/SD) Restoring Factorization @ Tevatron DSF from two/one gap: factorization restored! Diffraction from CDF2LHC K. Goulianos
CDF2LHC TOPICSTATUS • (Q2, t) dependence of DSF close to ready • Exclusive ccproduction close to ready • Low mass states in DPE need good trigger • Exclusive b-bbar production in DPE need b-trigger • x -dependence of DSFneed low lum run • Jet-gap-Jetw/jets in miniplugsneed low lum run Diffraction from CDF2LHC K. Goulianos
Diffraction @ LHC • Multigap diffraction • Exclusive production • of high mass states Diffraction from CDF2LHC K. Goulianos
Summary Derive diffractive from ND pdf’s and color factors @CDF @ LHC Multigap and High Mass Exclusive Diffraction CDF2LHC Special low-lum run needed for low-x and JGJ Diffraction from CDF2LHC K. Goulianos