ALEPH Status Report/(3&���-XO\��������

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Detector performance

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2-fermion cross sections

Lepton asymmetries

Single photon + missing energy

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10

20

30

40

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

|CosΘ|

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QCD - Jet rates

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10-2

10-1

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Pythia 5.7Herwig 5.9Ariadne 4.08

ALEPH (205 GeV)

PRELIMINARY203-208 GeV

WW cross section

0

2.5

5

7.5

10

12.5

15

17.5

20

160 170 180 190 200 210

Ecm(GeV)

WW

Cro

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RacoonWW / YFSWW 1.14GENTLE 2.1 (±0.7%)

ALEPH PRELIMINARY

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15

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7.5

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160 170 180 190 200 210

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pb 0.86 17.01

GeV 206.7At

pb 0.61 16.70

GeV 204.9At

WWCC03

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σ

ZZ cross section

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0.2

0.4

0.6

0.8

1

1.2

1.4

180 190 200 210

Centre-of-mass energy (GeV)

σ(e+

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ALEPH PRELIMINARY

Higgs searches

SM Higgs

0

5

10

15

20

25

60 70 80 90 100 110 120

MH(GeV/c2)

Eve

nts/

(2 G

eV/c2 )

ALEPH

preliminary

0

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0.2

0.3

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1

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1-c b

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Cb= 0.02100 pb-1

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tanβ=1.41

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(a)LLE−

ALEPH

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161-208 GeV 161-208 GeV 161-208 GeV

High ∆Μ

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ALEPH Preliminary

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ALEPH Preliminary

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Results

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Status

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Running requests

1. To run immediately in a mode which will give maximum luminosity at the highest energy - assumed to be 2 x 2.

2. To take at least 10 pb-1 at the highest energy using the reserve if necessary.

3. Continue to take data at high energy after the scheduled end of run until such time as the Higgs reach for a 3 sigma discovery, estimated on the basis of a three month continuation, is excluded at 95% confidence level.

4. If point 3 is reached before the end of September the collaboration considers that a dedicated run of 200pb-1 for the W mass at threshold will provide an excellent increase in the accuracy of the measurement of this fundamental parameter

5. A 0.5 pb-1 calibration run at the Z peak at the end of the run

6. Energy calibration should be a priority

Conclusions

All standard searches performed on 93 pb-1 @ 203-208 GeV

Good agreement with SM predictions

No evidence of new physics at high energy

Cannot rule out light sbottom production

Two good high mass Higgs candidates observed (1 SM, 1 fermiophobic)

Congratulations to LEP operations and RF groups!