6
41 .P lo ts of cr os s se ct io n s an d re la te d qu an ti ti es σ an d R in e
+e
−C ol lis io ns 10
-8
10
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10
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10
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10
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10
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10
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1 10 10
2σ
[m b]
ω ρ
φ ρ′J/ψ ψ(2S)
Υ Z 10
-1
1
10
10
210
31 10 10
2R
ω ρφ ρ′
J/ψψ(2S)
Υ Z √ s [G eV ]
Figure41.6:Worlddataonthetotalcrosssectionofe+e−→hadronsandtheratioR(s)=σ(e+e−→hadrons,s)/σ(e+e−→µ+µ−,s). σ(e+e−→hadrons,s)istheexperimentalcrosssectioncorrectedforinitialstateradiationandelectron-positronvertexloops,σ(e+e−→ µ+µ−,s)=4πα2(s)/3s.Dataerrorsaretotalbelow2GeVandstatisticalabove2GeV.Thecurvesareaneducativeguide:thebrokenone (green)isanaivequark-partonmodelprediction,andthesolidone(red)is3-looppQCDprediction(see“QuantumChromodynamics”sectionof thisReview,Eq.(9.7)or,formoredetails,K.G.Chetyrkinetal.,Nucl.Phys.B586,56(2000)(Erratumibid.B634,413(2002)).Breit-Wigner parameterizationsofJ/ψ,ψ(2S),andΥ(nS),n=1,2,3,4arealsoshown.Thefulllistofreferencestotheoriginaldataandthedetailsof theRratioextractionfromthemcanbefoundin[arXiv:hep-ph/0312114].Correspondingcomputer-readabledatafilesareavailableat http://pdg.lbl.gov/current/xsect/.(CourtesyoftheCOMPAS(Protvino)andHEPDATA(Durham)Groups,May2010.)Seefull-color versiononcolorpagesatendofbook.41 .P lo ts of cr os s se ct io n s an d re la te d qu an ti ti es
7R in L ig ht -F la vo r, C ha rm ,a nd B ea ut y T hr es ho ld R eg io ns
10-1110
102 0.511.522.53
Su m of ex cl us iv e m ea su re m en ts In cl us iv e m ea su re m en ts 3 lo op pQ C D N ai ve qu ar k m od el u, d, s
ρωφ ρ′ 234567 33.544.55
Mark-I Mark-I+LGW Mark-II PLUTO DASP CrystalBall BES
J/ψψ(2S) ψ3770ψ4040
ψ4160 ψ4415
c
2345678 9.51010.511MD-1ARGUSCLEOCUSBDHHM CrystalBallCLEOIIDASPLENA Υ(1S) Υ(2S)Υ(3S) Υ(4S)
b
R √ s [G eV ]
Figure41.7:Rinthelight-flavor,charm,andbeautythresholdregions.Dataerrorsaretotalbelow2GeVandstatisticalabove2GeV. ThecurvesarethesameasinFig.41.6.Note:CLEOdataaboveΥ(4S)werenotfullycorrectedforradiativeeffects,andweretain themontheplotonlyforillustrativepurposeswithanormalizationfactorof0.8.Thefulllistofreferencestotheoriginaldataand thedetailsoftheRratioextractionfromthemcanbefoundin[arXiv:hep-ph/0312114].Thecomputer-readabledataareavailableat http://pdg.lbl.gov/current/xsect/.(CourtesyoftheCOMPAS(Protvino)andHEPDATA(Durham)Groups,May2010.)Seefull-color versiononcolorpagesatendofbook.Quantenchromodynamik (QCD) Zoom in einen Teil des Eich-Systems: QCD (die S U (3 ) ; qu+gl)
QCD O(α )245 MeV 181 MeV
ΛMS(5)α (Μ )sZ 0.1210 0.1156
0. 1 0. 2 0. 3
0. 4
0. 5 α s (Q ) 1 10 10 0 Q [G eV ]
Heavy QuarkoniaHadron Collisionse+e-AnnihilationDeep Inelastic Scattering NL O
NN LO
Theory Data Lat tic e
211 MeV0.1183 s4