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X other methods : high pT jets at HERA and Tevatron
X 13
X Quark and Gluon densities 14
xU
vxu
Ux
xD
vxd
Dx
xg
2 = 10 GeV2 Q ZEUS-JETS fit tot. uncert. H1 PDF 2000 tot. exp. uncert. model uncert.
-410 -310 -210 -110 1
-410 -310 -210 -110 1
0
5
10
15
0
0.5
1
1.5
0
0.5
1
1.5
x
xf
ZEUS
many gluons at small x : frequent splitting g → gg [int color charge; brems-sing ]
perturbative picture [?] :
xg(x, Q2) ∼ exp√
log Q2 log 1/x
X Scheme dependence of parton densities :
X divergencies developg in higher order corrections, absorbed by renormalization ⇒X generates scheme dependent densities accdg to prescription; schemes :
X DIS parton densities: F2 remains unaltered sum of parton densities
X MS parton densities: only singular part absorbed ⇒ finite shift from DIS
X QCD coupling αs(Q2) in DIS
X [on low side of WA]
X world average αs(M2Z) = 0.119± 0.001 15A
X Scheme dependence of parton densities : 15B
X divergencies developg in higher order corrections, absorbed by renormalization ⇒X generates scheme dependent densities accdg to prescription; schemes :
X DIS parton densities: F2 remains unaltered sum of parton densities
X MS parton densities: only singular part absorbed ⇒ finite shift from DIS
X QCD coupling αs(Q2)
X world average αs(M2Z) = 0.119± 0.001
X Transition HERA → LHC
x
Q2 /
GeV
2
y =
1
y = 0.
004
.
HERA Experiments:
H1 1994-2000
ZEUS 1994-2000
Fixed Target Experiments:
NMC
BCDMS
E665
SLAC
10-1
1
10
10 2
10 3
10 4
10-6
10-5
10-4
10-3
10-2
10-1
1
X Higgs and new particles, e.g. susy, produced at LHC for M 2 ' 〈x2〉s :
〈x〉 ∼M/√
s ≥ 10−2 for M ∼ 100 GeV
X region for DGLAP evolution theoretically under good control : reliable predictions
X 16
3. pp COLLIDER TEVATRON
Xcharacteristics: pp ⇒ max energy in qq annihilation
Ep = Ep
Tevatron : cm energy√
s = 1.8→ 2.0 TeV
tot lumi ∼ 4 to 8 fb−1 [2008/9] Exps : CDF & D0
17A
3. pp COLLIDER TEVATRON
Xcharacteristics: pp ⇒ max energy in qq annihilation
Ep = Ep
Tevatron : cm energy√
s = 1.8→ 2.0 TeV
tot lumi ∼ 4 to 8 fb−1 [2008/9] Exps : CDF & D0
XTarget : (1) top quark discovery ⇐
(2) elw precision physics : W mass measurement ⇐trilin cplgs : non-Abelian gauge theory
(3) new physics discovery : Higgs boson(s) ⇐susy particles ⇐new gauge bosons W ′, Z′
extra space dimensions
... 17B
X TOP QUARK 18
XEvidence for t quark:
X SM anomaly free : ΣQF = 0
X = [0− 1] + 3[ 23− 1
3]
X PETRA/LEP : e+e− → bb : I3(b) = − 12
top : missing iso-partner
0.5
0
—0.5
0.50—0.5I3L
Γ(Z→bb)
AFB
(b) at35GeV
AFB
(b)at m
z
SM
I3R
X top-quark mass prediction : [tb] loop ⇒ W mass
µ decay ⊕ LEP : GF√2
= 4πα8 M2
Wsin2 θw
→ 2παM2
Zsin2 2θw [1+∆ρ]
∆ρt =GF m2
t
2πlog
m2t
M2W
prediction : mt = 166± 26 GeV
TOP QUARK
Discovery of t quark at Tevatron:
present value mt = 171.4± 2.1 GeV
Agreement between top mass prediction and measurement establishes validity
of electroweak GSW theory at the quantum level
X 19
X W± BOSON MASS 20A
XDrell-Yan production of W±, Z bosons at Tevatron:
Xdecays : W± → `±ν`
Xvs. : Z → `+`−
XTev : MW = 80.452± 0.059 GeV
WAv: MW = 80.392± 0.029 GeV
Xcrucial input for testing elw sector
Xin Standard Model and, e.g., Super-
Xsymmetry
Measurement Fit |Omeas−Ofit|/σmeas
0 1 2 3
0 1 2 3
∆αhad(mZ)∆α(5) 0.02758 ± 0.00035 0.02766
mZ [GeV]mZ [GeV] 91.1875 ± 0.0021 91.1874
ΓZ [GeV]ΓZ [GeV] 2.4952 ± 0.0023 2.4957
σhad [nb]σ0 41.540 ± 0.037 41.477
RlRl 20.767 ± 0.025 20.744
AfbA0,l 0.01714 ± 0.00095 0.01640
Al(Pτ)Al(Pτ) 0.1465 ± 0.0032 0.1479
RbRb 0.21629 ± 0.00066 0.21585
RcRc 0.1721 ± 0.0030 0.1722
AfbA0,b 0.0992 ± 0.0016 0.1037
AfbA0,c 0.0707 ± 0.0035 0.0741
AbAb 0.923 ± 0.020 0.935
AcAc 0.670 ± 0.027 0.668
Al(SLD)Al(SLD) 0.1513 ± 0.0021 0.1479
sin2θeffsin2θlept(Qfb) 0.2324 ± 0.0012 0.2314
mW [GeV]mW [GeV] 80.392 ± 0.029 80.371
ΓW [GeV]ΓW [GeV] 2.147 ± 0.060 2.091
mt [GeV]mt [GeV] 171.4 ± 2.1 171.7
X W± BOSON MASS 20B
XDrell-Yan production of W±, Z bosons at Tevatron:
Xdecays : W± → `±ν`
Xvs. : Z → `+`−
XTev : MW = 80.452± 0.059 GeV
WAv: MW = 80.392± 0.029 GeV
Xcrucial input for testing elw sector
Xin Standard Model and, e.g., Super-
Xsymmetry
80.3
80.4
80.5
150 175 200
mH [GeV]114 300 1000
mt [GeV]
mW
[G
eV]
68% CL
∆α
LEP1 and SLD
LEP2 and Tevatron (prel.)
X HIGGS BOSON(s) 21
X# 1. Many SM production channels
XXX pp→ H, WH, ZH, jjH
Xand results from both detectors are
Xneeded to
XXX– either exclude ∼ 2σ
XXX– or discover ∼ 5σ
XHiggs boson in Standard Model
Xin low-mass region:
X:: non-zero chance before LHC [?] :: l ) 2 (GeV/cHHiggs Mass m
100 110 120 130 140 150 160 170 180 190
)-1
Int.
Lu
min
osi
ty p
er E
xp. (
fb
1
10
102
SUSY/Higgs Workshop(’98-’99)Higgs Sensitivity Study (’03)
statistical power only(no systematics)
Discoveryσ5 Evidenceσ3
95% CL Exclusion
X# 2. Production rate of SUSY Higgs bosons Φ in b-quark fusion
XXX pp→ bbΦ [Φ = h, H, A]
Xpromising in part of susy parameter space [non-decoupling region] with large
XHiggs mix angle tan β
X SUSY PARTICLES 22A
Xfocus : charginos / neutralinos, susy partners of gauge and Higgs bosons
X squarks and gluinos, partners of quarks and gluons
X(1) golden channel: Drell Yan production pp→ χ±1 χ0
2 with χ02 → `+`−χ0
1
χ±1 → `±ν` χ0
1
pp→ `±`+`− :: trilepton signal
limit [mod.d] mχ±
1
≥ 124 GeV
X(2) squarks and gluinos : pp→ qq
gq
gg
X Chargino Mass (GeV)100 105 110 115 120 125 130 135 140