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Title of program: GRAPE-Dilepton(v1.1) *

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Program obtainable from:
CPC Program Library, Queen's University of Belfast, N. Ireland
and from
http://www-zeus.desy.de/abe/grape/. *

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Operating system under which the program has been tested:
UNIX
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Programming language used: Fortran77
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Memory required to execute with typical data:
7 Mwords for integrations,
9 Mwords for event generations
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Keywords:
dilepton,
lepton-pair,
ep collision,
Bethe-Heitler,
Z boson,
dipole form factor,
hadron tensor,
lepton tensor,
structure function,
parton density,
GRACE
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Nature of physical problem:
A precise estimation of the cross section of the electroweak
dilepton production in collisions
is required in various physics analyses,
where 848 Feynman diagrams can contribute.
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Method of solution:
The automatic calculation system GRACE is used
to obtain all of the relevant helicity amplitudes.
The phase space is divided into the 3 regions
according to the kinematics at the proton vertex,
and the 3 different calculation methods are applied.
The radiative corrections are included
using the structure function and the parton shower methods.
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Restrictions on the complexity of the problem:
Higgs, the proton-Z coupling and
lepton pair production through photon radiation from the proton
are not included.
The contribution from the resolved photon, i.e.
Drell-Yan process in collisions is not included. *

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Typical running time:
1 hour for a cross-section integration
and
1 msec per 1 event for an event generation *

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