Elegent - old version
This page describes an old version of Elegent (used up to CMSSW 4.2.4). For the up-to-date version, see
CompElegent.
Generates p-p and ap-p elastic scattering events according to one of the available hadronic and Coulomb-interference models.
Hadronic models
- Islam et al. According to Int.J.Mod.Phys.A21:1-42,2006. Tags
islam_bfkl
(for the BFKL/hard pomeron version) or islam_cgc
(for the color-glass-condensate version).
- Petrov, Predazzi, Prokudin. According to Eur.Phys.J.C28:525-533,2003. There are two versions implemented - with 2 pomerons (tag
ppp2
) and with 3 pomerons (tag ppp3
).
- Bourrely, Soffer, Wu. According to Eur.Phys.J.C28:97-105, 2003. Tag
bsw
.
- Block, Halzen. According to Phys.Rev.D60:054024,1999. Tag
bh
.
- Jenkovszky et al. According to arXiv:1105.1202 (2011). Tag
jenkovszky
.
- simple exponential, tag
exp
.
Coulomb-interference models
- West-Yennie, see Phys.Rev.172:1413-1422,1968. Tag
WY
.
- Kundrát-Lokajíček, see e.g. Z.Phys.C63:619-630,1994. Tag
KL
.
Besides those, the Elegent recognizes these tags
-
PH
to neglect the Coulomb-interference and take a hadronic model only and
-
PC
to take only the Coulomb amplitude and neglect hadronic scattering.
ElegentCDFBuilder
Before the actual event generation, one has to calculate CDFs (cumulative distribution functions) for the energy of interest. They're stored in ROOT files under the
Elegent/data
directory. It is very likely that all files you need, would be already there. If not, you can use
python/ElegentCDFBuilder_cfg.py
to do it yourself.
Naming schemes
The CDF ROOT files follow this convention
<E>_<|t|_min>_<|t|_max>_<number of sampling points>.root
where
E
stands for beam energy in GeV (i.e. half of cms energy) and
t_min
and
t_max
are the boundaries of supported t-range in GeV^2.
For
ElegentSource
, the CDF choice is in the form
<coulomb-interaction tag>/<hadronic-model tag>
for example
KL/ppp3
.
The recommended usage of ElegentSource
As for every energy there is one preferred/default ROOT file with CDFs, the
ElegentSource_cfi.py
includes function
ElegentDefaultFileName(energy)
which returns the default filename for the given energy (string parameter). Hence a recommended usage is a follows
energy = "3500"
...
import IOMC.Elegent.ElegentSource_cfi
process.generator = IOMC.Elegent.ElegentSource_cfi.generator
process.generator.fileName = IOMC.Elegent.ElegentSource_cfi.ElegentDefaultFileName(energy)
process.generator.verbosity = ...
...
ElegentCalculateDetails
ElegentCalculateDetails
is a plugin that can take any of the ROOT files in the
data
directory and calculate some more detailed quantities like B(t), rho(t), etc. These would be stored in a file with
.details.root
extension.
makePlots.asy
makePlots.asy
is an
Asymptote
script take takes the
.root
and
.details.root
files and coverts them into a PDF with a standard set of plots.
--
JanKaspar - 23-Oct-2009