V. Šimák, D0 FNAL and CTU Prague 1

Measurement of the differential cross section dσ/dt in elastic antiproton-proton scattering at

V. Šimák D0 experiment and CTU Prague

for D0 experiment

7/5/2012

V. Šimák, D0 FNAL and CTU Prague 2

MotivationElastic scattering - first results in any hadrons' experiment

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Several phenomenology models:

-Geometrical scaling-Clouds structure-…….

L.M. Dremin: aXiv. 1206.5474v1 [hep] 24. Jan. 1012

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In Run II at Tevatron: D0 + PFD (2002)

Covered regions for scattered protons/antiprotons

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FPD scintillating fiber detector

Layers

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Comparison of detector y coordinatesIn the spectrometers Pu and Pd

Difference in reconstructed t between proton and antiproton, comparison of Monte Carlo with the data

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Monte Carlo comparison

Trigger efficiencies for detectors: 50% to 70%

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Position of detector with respect to beam center

Primary vertexreconstruction

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The correlation plots y-p vs y-ap for the first detectors .The dashed lines correspond to the fiducially requirements applied

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Trigger efficiencies for first four detectors: 50% to 70%

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dn/dt raw signal selection , background , applied acceptance, applied eff. and acceptance:

V. Hynek7/5/2012

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Results

Change of slope at

A. Brandt, C. Avila

b = 16.86 ± 0.10 (stat) ± 0.20 (sys) Submitted to PRD

Fermilab-Pub-12-263-E

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Comparison of result with other experiments

Measurement of elastic scattering with FPD cover larger and higher that experiments: UA4, UA8, CDF

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TEVATRON and D0 detector have finished all data collection but the analyses of full set of data is continuing

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Thank you

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