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500 fb-1 SM Data Sample at Ecm=500 GeV

Data Sample

Stdhep files for an Ecm=500 GeV SM data sample are
available at ftp://ftp-lcd.slac.stanford.edu/ilc/ILC500/StandardModel/ .
There are 487,603,537 events (250 fb-1 luminosity) with -80% electron/ +30% positron polarization,
and 474,837,805 events (250 fb-1 luminosity)  with +80% electron/ -30% positron polarization.

Event Weight

Due to the presence of some high cross section processes the events are not completely unweighted.
The event weight must therefore always be considered when analyzing events.
This weight is stored in the variable EVENTWEIGHTLH in the stdhep common block HEPEV4.

Process Identification

Events corresponding to hundreds of different processes are stored in random order in the stdhep files. For each event
the variable IDRUPLH from the stdhep common block HEPEV4 is used to identify the process.

Suppose that an event has IDRUPLH=14995 . The information about the generation of this event
can be found in the directory ftp://ftp-lcd.slac.stanford.edu/ilc/ILC500/StandardModel/run_output/w14995/run_01/ .
For example the log file is ftp://ftp-lcd.slac.stanford.edu/ilc/ILC500/StandardModel/run_output/w14995/run_01/whizard.log ,
the whizard input file is ftp://ftp-lcd.slac.stanford.edu/ilc/ILC500/StandardModel/run_output/w14995/run_01/whizard.in
and cross section information is in ftp://ftp-lcd.slac.stanford.edu/ilc/ILC500/StandardModel/run_output/w14995/run_01/whizard.n3n3n3n3ss_o.out

Beamstrahlung

The following lines in whizard.in control the beamstrahlung simulation:

USER_spectrum_on = T
USER_spectrum_mode = -2

The first line indicates that a user-supplied function is used to simulate beamstrahlung. A copy of this function can
be found in ftp://ftp-lcd.slac.stanford.edu/ilc/ILC500/StandardModel/whizard-src/user.f90

The absolute value of USER_spectrum_mode determines which beamstrahlung spectrum is used, with the sign +/- indicating
electron/positron beam, respectively. For the 500 fb-1 SM data sample this absolute value is always 2, and corresponds
to the Guinea-Pig beamstrahlung data contained in the directory ftp://ftp-lcd.slac.stanford.edu/ilc/ILC500/StandardModel/guinea-pig/ilc_0500_may05_run05_seed06/
This spectrum represents the default ILC Ecm=500 GeV design in August 2005.

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