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√ ^ s (GeV)

Cross section (pb)

e ⁺ e ⁻ →e ⁺ e ^– qq ⁻ e ⁺ e ⁻ →qq ⁻ (γ) e ⁺ e ⁻ →µ ⁺ µ ⁻ (γ) e ⁺ e ⁻ →νν ^_ (γ)

e ⁺ e ⁻ →W ⁺ W ⁻ e ⁺ e ⁻ →ZZ e ⁺ e ⁻ →γγ e ⁺ e ⁻ → W ⁺ W ⁻ γ

L3 preliminary

10 ^-1 1 10 10 ² 10 ³ 10 ⁴

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Measurement Fit |O ^meas −O ^fit |/σ ^meas

0 1 2 3

0 1 2 3

∆α _had (m _Z )

∆α ⁽⁵⁾ 0.02758 ± 0.00035 0.02767 m _Z [GeV]

m _Z [GeV] 91.1875 ± 0.0021 91.1874 Γ _Z [GeV]

Γ _Z [GeV] 2.4952 ± 0.0023 2.4959 σ _had [nb]

σ ⁰ 41.540 ± 0.037 41.478 R _l

R _l 20.767 ± 0.025 20.742 A _fb

A ^0,l 0.01714 ± 0.00095 0.01643 A _l (P _τ )

A _l (P _τ ) 0.1465 ± 0.0032 0.1480 R _b

R _b 0.21629 ± 0.00066 0.21579 R _c

R _c 0.1721 ± 0.0030 0.1723 A _fb

A ^0,b 0.0992 ± 0.0016 0.1038 A _fb

A ^0,c 0.0707 ± 0.0035 0.0742 A _b

A _b 0.923 ± 0.020 0.935

A _c

A _c 0.670 ± 0.027 0.668

A _l (SLD)

A _l (SLD) 0.1513 ± 0.0021 0.1480 sin ² θ _eff

sin ² θ ^lept (Q _fb ) 0.2324 ± 0.0012 0.2314 m _W [GeV]

m _W [GeV] 80.410 ± 0.032 80.377 Γ _W [GeV]

Γ _W [GeV] 2.123 ± 0.067 2.092 m _t [GeV]

m _t [GeV] 172.7 ± 2.9 173.3

Summer 2005

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a)

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Cross section (nb)

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b)

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b)

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√s ^ (GeV) σ νν _ γ (pb)

KKMC NUNUGPV KORALZ a)

<√ ^ s > = 198 GeV

σ _kkmc / σ _nunugpv = 1.002 ± 0.002 σ _koralz / σ _nunugpv = 1.016 ± 0.003 e ⁺ e ⁻ → νν ^_ γ , νν ^_ γγ

3.75 4 4.25 4.5 4.75 5

190 195 200 205

√s ^ (GeV) σ νν _ γγ (pb)

KKMC NUNUGPV KORALZ b)

e ⁺ e ⁻ → νν ^_ γγ

<√ ^ s > = 198 GeV

σ _kkmc / σ _nunugpv = 1.03 ± 0.01 σ _koralz / σ _nunugpv = 1.06 ± 0.01 0.26

0.28 0.3 0.32 0.34

190 195 200 205

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