- 1
- Work supported by the Helmholtz-Gemeinschaft (VH--NG--005)
- 2
- WHIZARD has been checked to work with recent
versions of the g95, NAG, Lahey/Fujitsu, and Intel compilers
(Intel/Linux) and the Compaq compiler (Alpha architecture). If you
experience problems, first check the compiler version, since some
compiler bugs may have been fixed only very recently.
- 3
- This is the
NAMELIST format as defined by the Fortran language standard.
- 4
- Otherwise, the matrix element would contain the
unphysical decay µ+-> nµ_ud_ since the u and d
quark masses are always zero.
- 5
- The macro package is called gamelan and is included in
the distribution. MetaPost must be available on the system; this is
determined by configure when WHIZARD is installed.
- 6
- Doing this
the first time, this make, or make gml has to be
issued in the main directory, so gamelan is compiled. Later, it
also works in the results subdirectory where the files
reside.
- 7
- The compiler and
compiler flags are set in chep-src/unix_com/CC.
- 8
- If, for the
selected Fortran compiler, command-line arguments are not supported,
the program will just display the list of processes and exit.
- 9
- A better method is to give the
user-created file a different name and use a symbolic link to
whizard.prc instead. The same applies to
whizard.in.
- 10
- if MadGraph or O'Mega are used for matrix element
generation
- 11
- The current implementation is not well suited for
single-particle processes if the initial-state energy distributions
are strongly peaked. A similar caveat holds for processes with an
s-channel resonance, for instance, e+e-->µ+µ- with a
continuous beamstrahlung/ISR spectrum for the incoming electrons,
integrated over the whole energy range. Nevertheless, with large
statistics reasonable results can be obtained.
- 12
- Naively summing over identical particles in the
final state may result in double-counting, and becomes very
inefficient if many combinations are allowed. The `c' option takes
care of both issues (see below).
- 13
- If the list of flavor
sums or the number of particles in the process becomes very long, it
may happen that the compiler complains for the number of continuation
lines becoming too large. This problem is easily fixed by increasing
the number of continuation lines accepted by the compiler. You should
consult your Fortran compiler documentation for the appropriate flag
which may then be set in the config.site file. Don't forget
to clean up and configure before restarting the compilation.
- 14
- The current official CompHEP version allows for
polarization and has an interface for flavor sums. These features are
not yet supported by the WHIZARD--CompHEP interface.
- 15
- Those that are part of the
WHIZARD system. Precompiled libraries such as the PDFLIB have to
present on the target system and can be enabled there if they are
needed.
- 16
- This
works only if PYTHIA has been linked.
- 17
- In the present implementation,
full color information is available with MadGraph only, while flavor
summations require O'Mega; this will improve, however.
- 18
- Similar restrictions are possible with the
official CompHEP and MadGraph versions, but not supported by
WHIZARD.
- 19
- The
latter are necessary because the procedure makes sense only if input
data have changed, so the checksum will be invalid. This makes the
user responsible for guaranteeing compatible input data in both runs;
otherwise the program may crash.
- 20
- NLO matrix elements are
nontrivial, and WHIZARD may be not the appropriate program for
dealing with them. An obvious limitation is that the user weight
function does not take polarization into account.
- 21
- If used with
recalculate=T, this limitation is absent, since reweighting
will be applied after adaptation and event rejection. In that
case, an unmodified event sample has to be generated first.
- 22
- This
feature is available only on certain systems. Currently, the NAG,
Lahey/Fujitsu, and Intel compilers (PC/Linux) and the Compaq compiler
(Alpha) are supported. On other systems, command line options are
without effect.
- 23
- To access the module
information, several subdirectories must be included in the module
search path of the compiler. Inspect the setting of F90INCL in the
Makefile in the whizard-src subdirectory.
- 24
- This works for a
Fortran 95 main program; the analogous steps for a main program in a
different language will require modifications of whizard.ld,
in particular the additional linking of the compiler-specific Fortran
95 runtime library.
- 25
- See footnote 5.8.
- 26
- For a genuine analysis, one should
inspect the underlying assumptions and try to find a consistent
parameter set. Since the WHIZARD matrix elements are evaluated at
tree level, some higher-order corrections should not be included in
the Higgs width.
- 27
- This number should be taken with a grain
of salt. See footnote 6.1.1.
- 28
- By reducing
the parameter weights_power in the input file, these
fluctuations can be somewhat dampened.