Derar Fluka users,
sorry for "spamming" your mailboxes, since in the announcement of the
fluka2011.2x release the RELEASE NOTES appeared garbled, the announcement
is sent again with the rlease notes explicitly included at the bottom,
please read them
The Fluka developer team
Dear FLUKA Users,
A new Fluka release, fluka2011.2x, is available on the web site.
It substitutes for all purposes fluka2011.2c, as usual no further
assistance will be provided for fluka2011.2c and all users are kindly invited to
move to fluka2011.2x.
This is NOT YET the full new release the development team is working on since a
long time, but rather an "interim" release (hence the
out-of-sequence name) which marries fluka2011.2c with some new important
features which were felt ready for production.
By far the most important novelty is the inclusion of the "new" Dpmjet-3 as
improved in the past years, which compares significantly better than
the previous version with available LHC data at centre-of-mass energies
in excess of 2 TeV.
The release for the time being includes tar files and rpm's for Linux versions
compiled with g77 and gfortran-7.3. It also includes for the first time a Mac
version compiled with gfortran 7.2, which is still
somewhat experimental. Versions for Linux and Mac compiled with gfortran 6.4
will follow in the next weeks for those who did not yet update
to 7.x. No Flupix image for Windows will be provided, rather an
image based on a different environment is in the work and will appear sometimes
in the (near) future.
Users are strongly invited to read the release notes (a copy is attached to this
message) for further details. As with every new release, some problems are
possible despite the extensive checks, if so please contact the developer team
through our discussion list.
The Fluka developer team
======== RELEASE NOTES ==========
- Release notes for Fluka2011.2x -
This is an out-of-sequence release with some important changes physics-wise.
Indeed the major revision number of this release is still 2011, the minor
revision number is 2, however the "x" signifies that major changes are
now included with respect to the previous 2011.2... releases.
The rationale for this "interim" release is explained in the following.
For various reasons, a full brand new release, which will include a pletora of
improvements and new features, is still several months in the future.
However, it was felt that at least some important features which
are ready for distribution could be backported to 2011.2 and made
available now to our user community while waiting for the new full release.
As usual, with this interim release all FLUKA versions older or equal to
2011.2c are obsoleted and they shall no longer be used according to
the conditions spelled out in the FLUKA license (circumvention of the
expiration date is not permitted).
No debugging/maintenance/assistance will be provided for older versions.
This release contains a few small fixes, and some important physics changes,
in particular concerning very high energies, where the Dpmjet-3 code is used.
Please note the standard FLUKA references to be quoted and the revised
license (which you can find in the LICENSE.2011.2x file, or printed by the
code when it runs):
PHYSICS IMPROVEMENTS:
- The vastly revised and improved (new) Dpmjet-3 is now included,
substituting the previous version and removing the need to distribute
Dpmjet-2.5 since the new Dpmjet-3 is able to treat all particles
at cosmic ray energies.
The upgraded Dpmjet-3 results mostly from the PhD work of Anatoli
Fedynitch, and it has been benchmarked against LHC data, showing
significantly better reproduction of experimental data at
centre-of-mass energy in excess of 2 TeV
- The default option governing the iterative convergence of the kinematics
of nucleon-nucleon scattering in nuclei has been changed providing
(marginally) better results in some cases
- The calculations of the DPA contribution by hadrons below energy cut-off
has been improved. Still the treatment is approximate, so
one must run with the lowest possible threshold for charged hadrons
when looking for DPA's
BUG FIXES AND TECHNICAL UPDATES:
- A problem affecting the sampling of the angular distribution of pp
scattering at energies around 400-700 MeV has been fixed, the impact
is minimal
- Some dimensions have been increased where user experience showed that
limitations could occur
- Several sanity checks have been backported from the development tree
in the hope to catch common input mistakes
- The #define directive has been improved, now it allows to define
a value for a symbolic name, eg
#define BeamEne 200.0
and use it in a data card, eg
BEAM $BeamEne
-- IMPORTANT WARNINGS FOR THE USERS --
We would like to stress once more that whenever activation is a concern or,
"precise" particle production calculations are required, the PEANUT extended
model, as well as heavy particle evaporation/fragmentation and coalescence
should be switched on (see below for details)
- Already starting from Fluka2006.3, a new high energy event generator had
been developed, based on the sophisticated nuclear physics of PEANUT
coupled with the proved FLUKA Dual Parton Model description for
hadron-hadron collisions and a brand new Glauber cascade treatment. Starting
from this release, this model is substituting as default the old one
(PEANUT was already the default below 5 GeV). This is equivalent to:
PHYSICS 1.D+5 1.D+5 1.D+5 1.D+5 1.D+5 1.D+5PEATHRES
All thin target benchmarks of the code by the development team are run
with the new model, the development of the old one being frozen. Only
this model should be considered representative of the ultimate FLUKA
performances. The PHYSICS cards which allows to switch back to the old
model (highly discouraged) is:
PHYSICS 5. 5.7 5. 5. -1. 5. PEATHRES
Also the new model potentially provides a fully featured simulation of
high energy quasi-elastic events, but this requires cleaning up some FLUKA
inconsistencies and therefore is not yet activated.
- Whenever residual nuclei (and residual dose rates) scoring is of
importance, or accurate neutron yields are required, the heavy residual
emission ("fragmentation") and the coalescence emission of fast complex
particles should be switched on, through the following data cards:
PHYSICS 3.0 EVAPORAT
PHYSICS 1.0 COALESCE
and (as a consequence of coalescence) it would be wise to link with
rQMD-2.4 (and DPMJET) and activate ion transport and interactions. These
suggestions are mandatory for residual nuclei calculations.
Those options are not on by default because the heavy evaporation carries a
big CPU penalty which would be a waste for most problems when residuals are
not a issue.
- There is a known issue with photofission: the photonuclear interaction
model is not up-to-date with respect to the present fission model.
As a result, photofission can be heavily underestimated at low photon
energies for fissile materials. A fix is already implemented in the
development tree and it will be included in the next full release.
- !!!! MAJOR WARNING, please read !!!!
The use of so-called "expressions" inside the Flair preprocessor, those
writing pseudo-comments in the input file like
!_at_what.1=-1.5e-2
has been found to be prone to potentially dangerous situations, where
FLUKA runs with parameters different from those intended by the user with
no detectable warning. This is particularly true if a Flair generated
input is modified by editing it outside Flair or viceversa, or in all
cases where inputs using the #include directive together with those kind
of expressions or similar operators are modified in Flair.
The developer team has identified already a few scenarios where because of
these shortcomings of the Flair implementation, FLUKA could run with a
setup different from the one shown in the Flair screen.
Therefore it is STRONGLY recommended to refrain from using such Flair
features until a safer implementation will be available (the developer
team is working on it). If you cannot avoid using those features, please
ALWAYS CHECK what ended up into the input file (and the corresponding
interpretation in the output file), since what will be actually
run is what is written in the WHATs fields of the
input file (!... comments ignored) and not what the Flair screen can
show in case they are different. Warnings have been added in the .err
and .out files for this purpose.
-- PLATFORMS UNDER WHICH FLUKA SHALL BE RUN --
This version of the code should be run on the platforms for which it
has been released, that is Linux x86 under g77 (which runs on both
32 and 64 bit machines) and Linux x86_64 under gfortran. The latter
requires a recent version of the gfortran compiler, given the
incompatibility between different versions of gfortran.
For the first time, a Mac OS version compiled with gfortran is also
available, on a tentative basis.
The available gfortran versions are compiled with gfortran 7.3 (Linux) and
gfortran 7.2 (Mac). At a later stage, files compiled with gfortran 6.4
will be also made available for both platforms.
The code has been checked and validated for these platforms/compilers
only.
The availability of the source code shall not be exploited for tentative
builds on other architectures or with different compilers/compiler options
than the ones recommended by the development team. Our experience shows that
for a code of the complexity of FLUKA the chances of hitting one or more
compiler issues are pretty high. Therefore users shall not make use
for every serious task, including whichever form of publication or
presentation, of code versions built on platforms and/or with compiler
options which have not been cleared as safe by the development team.
-- INSTRUCTIONS FOR THE GFORTRAN VERSION --
The gfortran (64 bits) version is for x86_64 machines and cannot be run
on 32 bit architectures. The FLUKA scripts recognize which version the
user is running according to the following:
a) The FLUFOR environmental variable, which can take the values "g77"
or "gfortran"
b) If FLUFOR is not set, if the directory name contain the "gfor" string
gfortran is assumed, g77 otherwise
c) If gfortran is selected by means of a) or b), the additional variable
GFORFLU can be set to specify the specific version of gfortran to be
used if more than one is available. Please note that gfortran >= 6.3
is required. For example, if on your machine "gfortran" points to a
version < 6.3, and "gfortran63" points to version 6.3, you can set
GFORFLU to "gfortran63" and happily use the FLUKA gfortran (64 bits)
version
-- FLUKA AND LICENSING CONDITIONS --
Use of FLUKA must be compliant with the FLUKA user license, which is
not a GPL-like license. Therefore, users shall read carefully the
licensing conditions as available in the distribution tar flile,
on the FLUKA website and in the output files.
In case of doubts or need for special authorizations, users shall contact
contact either:
- the Fluka Coordination Committee (FCC)
for licensing and commercial questions (fcc_at_fluka.org)
- the Fluka Scientific Committee (FSC) (fsc_at_fluka.org) for questions
related to publications or releases
This interim release of FLUKA is carried out under the INFN-CERN
Collaboration Agreement for the Maintenance and Development of the FLUKA
code.
-- REFERENCES TO BE QUOTED --
The use of the FLUKA code must be acknowledged explicitly by quoting
at least the following set of references
- A. Ferrari, P.R. Sala, A. Fasso`, and J. Ranft,
"FLUKA: a multi-particle transport code",
CERN 2005-10 (2005), INFN/TC_05/11, SLAC-R-773
- G. Battistoni et al.,
``Overview of the FLUKA code'',
Annals of Nuclear Energy 82, 10-18 (2015)
(this substitutes the following one which was suggested up to now:
T.T. Bohlen, F. Cerutti, M.P.W. Chin, A. Fasso`, A. Ferrari,
P.G. Ortega, A. Mairani, P.R. Sala, G. Smirnov, and V. Vlachoudis,
"The FLUKA Code: Developments and Challenges for High Energy and
Medical Applications", Nuclear Data Sheets 120, 211-214 (2014))
Use of Flair must be acknowledged using the following reference:
- V. Vlachoudis, Proc. Int. Conf. on Mathematics, Computational
Methods & Reactor Physics (M&C 2009), Saratoga Springs, New York, 2009
Additional FLUKA references can be added, provided they are
relevant for the problems under consideration, in particular
the use of some specific models should be individually acknowledged, eg:
For the use of the neutrino event generator (NUNDIS):
- G. Battistoni, A. Ferrari, M. Lantz, P. R. Sala and G. I. Smirnov,
"A neutrino-nucleon interaction generator for the FLUKA Monte Carlo code",
Proceedings of 12th International Conference on Nuclear Reaction
Mechanisms, Varenna, Italy, 15-19 June 2009,
CERN-Proceedings-2010-001 pp.387-394.
For the use of (the modified) rQMD-2.4:
- H. Sorge, H. Stoecker, and W. Greiner, Annals of Physics 192, 266 (1989)
- V. Andersen. F. Ballarini, G. Battistoni, M. Campanella, M. Carboni,
F. Cerutti, A. Empl, A. Fasso`, A. Ferrari, E. Gadioli, M.V. Garzelli,
K. Lee, A. Ottolenghi, M. Pelliccioni, L.S. Pinsky, J. Ranft, S. Roesler,
P.R. Sala, and T.L. Wilson,
"The FLUKA code for space applications: recent developments"
Advances in Space Research, 34(6), 1302-1310 (2004).
For the use of DPMJET-3:
- S.Roesler, R.Engel, J.Ranft: "The Monte Carlo Event Generator DPMJET-III"
in Proceedings of the Monte Carlo 2000 Conference, Lisbon, October 23-26
2000, A. Kling, F. Barao, M. Nakagawa, L. Tavora, P. Vaz eds.,
Springer-Verlag Berlin, 1033-1038 (2001).
- A. Fedynitch, PhD Thesis,
https://cds.cern.ch/record/2231593/files/CERN-THESIS-2015-371.pdf
For medical applcations of FLUKA:
- G. Battistoni, J. Bauer, T.T. Boehlen, F. Cerutti,
M.P.W. Chin, R. Dos Santos Augusto, A. Ferrari, P.G. Ortega,
W. Kozlowska, G. Magro, A. Mairani, K. Parodi, P.R. Sala, P. Schoofs,
T. Tessonnier, V. Vlachoudis,
"The FLUKA code: An accurate simulation tool for particle therapy",
Frontiers in Oncology, Radiation Oncology Section, 00116 (24 pages)
(2016)
Extracts from the release notes of Fluka2011.2 and other previous versions
are reported below.
==========================================================================
- Release notes for Fluka2011.2c -
Physics improvements:
- When treating anti-nucleon annihilation, negative pions and negative
muon absorptions on compound/mixtures, the evaluation of the relative
probability of annihilation/capture on different target
components has been switched from a naïve “Z law” to more sound
approaches
- Stopping power in gaseous Helium: the Ziegler fitting coefficients
for gaseous Helium have been implemented (in addition to those for
liquid He) and are automatically applied when the defined Helium is
gaseous (as the default FLUKA HELIUM is)
- Stopping power in graphite vs amorphous carbon: the distinction has
been implemented following the NIST recipe, however given the very
close densities (1.7 vs 2.0), the user must be aware that for
carbon the code will choose the one closer to the inut density
(eg for rho > 1.85 will use amorphous carbon, below graphite)
- Improved fit to the reaction cross section for protons on very heavy
targets. The previous parametrizations was increasingly too high for
Z >= 90
Bug fixes and technical updates:
- Fixed possible crash in the evaporation stage for extremely excited
superheavy fragment
- Fixed possible crash (insufficient stack dimensions) when using PEANUT
at energies above several TeV
- Fixed inconsistency in reading repetitive LOW-MAT cards for
the same material not immediately following each other
- Fixed rare bug in virtual photon interactions
- Fixed bug in the treatment of biasing of bremsstrahlung by positrons.
(apparently never met by anybody)
- Maximum number of USRTRACK estimators increased to 500
- Release notes for Fluka2011.2b -
This release contains a few small fixes, one of critical importance for DPA
calculations, and a significant functionality improvement with respect to
Fluka2011.2.17 (the latest respin of Fluka2011.2).
New functionality:
- New extended format for voxel geometries/phantoms. Now the voxel files
can contain an arbitrary number of extra records of 80 characters
each, which are read and interpreted as ordinary input cards. This
allows to embed in the voxel files informations as material
definitions, material assignments, correction factor etc, which are
often generated by automatic programs out of a CT scan. Flair
contains tools for reading CT scans in Dicom format, and
automatically generates a voxel file containing the material and
correction factor informations according to a Hounsfield number to
material/density translation algorithm which can be tuned by the
user.
- Release notes for Fluka2011.2 -
This release is a major step in the FLUKA development cycle with
respect to Fluka2008.3(d): it adds new features and there are
important physics improvements.
All FLUKA versions older than Fluka2008.3d and starting since 1989,
are declared obsolete and will no longer be supported.
Therefore they shall no longer be used for any publication according to
the FLUKA User License.
New features:
- This release, as well as future ones, is under a revised
License. There is no practical change for users, however please
take the time to read it. An explaination of what some
points of the License mean (those that in the past resulted in
possible misunderstandings) is available on the web site.
- Stopping power models have been thoroughly reworked, and are now
more precise particularly for heavy ions. In particular, the Barkas
(Z^3), Bloch (Z^4), and Mott corrections have been implemented.
- Nuclear stopping power is now calculated and taken into account.
It matters only for heavy ions at low energies, however it is an
essential prerequisite for NIEL and DPA calculations (see next
point)
- Radiation damage (Non Ionizing Energy Loss, NIEL, and Displacements
Per Atom, DPA) can now be computed and scored. The electromagnetic
part is still under refinement, in particular the contributon of
bremsstrahlung and pair production has to be implemented, as well as
the effect of using the Mott cross section rather than the Rutheford one.
The DPA-SCO, NIEL-DEP, and RES-NIEL generalized particles have been
added for this purpose
- The LPM (Landau-Pomeranchuk-Migdal) effect has been extended to pair
production (it was already active for bremsstrahlung)
- The lower limit for photon transport has been lowered to 100 eV.
Macroscopic surface effects (refraction/reflection) are not treated.
- Several improvements in the hadron-nucleus event generators
have been implemented
- Nuclear deexcitation by photon emission makes use of an extended
database of known levels and transitions. The evaporation stage is
also consistent with this database.
- The Boltzmann Master Equation, BME, model for heavy ion interactions
at low-medium energies is now included in the distributed version.
It can handle all projectiles with A>=4 on all targets, with the
exception of systems lighter than (alpha, 6Li). BME is invoked for
projectile energies lower than 125 MeV/A, however its limit of validity
is 150 MeV/A.
- The BME is still in a developing phase, it has been extended and
improved very recently, therefore the authors would like to warn
users about possible bugs, and would be very grateful to receive
feedback about possible problems.
- A new card, IONTRANS has been added to control the transport/interaction
of heavy ions. As a consequence, the EVENTYPE card is now obsolete.
- Several new options are now available in order to define spatially
distributed sources. Check the manual for the description of the
FLOOD, CART-VOL, SPHE-VOL, and CYLI-VOL option in the BEAMPOS card
- Pre-built source routines for special cases are now supported under
the SPECSOUR card. The first one allows an easy setup of colliding
beam interactions.
- A pre-built source routine, also available under SPECSOUR, and related
auxiliary files and examples, can simulate atmospheric showers from
cosmic rays and Solar Particle Events (see the manual for details).
- A new body, a generic quadric QUA, has been introduced in the geometry
- Geometry transformations: directives allowing roto-translations and
expansions for sets of bodies are now available in geometry.
They can be applied also to the voxel part, when existing.
- The "sophisticated" Compton scattering, including electron binding
and Doppler effects is now activated by default for "defaults"
CALORIME, PRECISIO, EM-CASCA, or HADROTHE
- A few compounds of dosimetric interest are now available as pre-defined
materials, see the manual for details
- Additional material have been included in the low energy neutron library,
some materials have been reworked from newer evaluations, and several
materials are now available at 430 K
- The old 72 groups neutron library has been declared obsolete and is
no longer distributed
- It is now possible to use a different material assignment for the
transport of prompt and radioactive decay radiations. Only switching
to vacuum or blackhole is supported, through the ASSIGNMAT
card. WARNING for user routines: the array MEDIUM has changed :
MEDIUM (MREG ) --> MEDFLK (I, MREG) I=1 or I=2 for prompt and
decay radiation respectively.
- Time scoring has been added for USRYIELD
- A generalized estimator, NET-CHRG, of net charge (algebraic sum of
positive and negative charge) is now available
- A new dose equivalent estimator, DOSEQLET, based on convolution with
the Q(LET) relation as defined in ICRP60 is now available
- The #include <filename> directive is now supported in the input file.
- There is no longer a default material assignment. Previously BLCKHOLE
was assigned to all regions, except for region 2 which was assigned
COPPER. Now the program stops whenever a region has no material
assigned.
Most of the physics improvements are brand new and still unpublished.
This version should not be used to publish results about
individual model validation/benchmarking (see the license),
in particular but not only when the new features are concerned.
In case of doubt please contact the FLUKA Collaboration Committee,
through fcc_at_fluka.org.
=== Fluka2008.3d ===
Functionality additions:
- Setting WHAT(4)=1. in the START card allows to trigger a dump core
everytime the built-in abort routine, FLABRT, is called. This can be
useful for debugging unwanted situations, which when caught runtime
by FLUKA trigger an automatic abort of the run
- The search path for OPENing auxiliary files has been protected against
user path including directories named "fluka_xxxx" which were
erroneously interpreted as the temporary directory created runtime
by the code
=== Fluka2008.3c ===
Functionality change with respect to the use of FLUGG and VMC (Virtual
Monte Carlo):
- FLUGG: starting from this patch version, FLUGG is better supported
by Flair. Most Flair functionalities can be used with FLUGG, having
care to point to the correct executable. In order to exploit fully
this capability, please download also the latest FLUGG release, as well
as the latest Flair release, both available from the FLUKA web site
- VMC: due to several examples of (inadvertent) use of the FLUKA-VMC
interface by people/groups who never asked for the required derogation
to the license, the hooks for VMC have been removed. A special version
with the hooks reactivated is available on the FLUKA website
under a download procedure reserved for the authorized experiments.
IMPORTANT WARNING: there are hints of possible bugs with the
FLUKA-VMC interface. They have been reported to the VMC developers:
no feedback up to now. Meanwhile, its use is discouraged even for the
authorized experiments. Furthermore, we remind that the VMC
interface supports only a minimal fraction of FLUKA capabilities,
and therefore the FLUKA development team urges all users to stick
with the native code
=== Fluka2008.3b (patch version of Fluka2008.3) ===
New functionality:
- Compton scattering with full acount for binding and orbital electron motion:
up to now FLUKA included two possibilities for the treatment of Compton
scattering:
1) "naive" scattering on free electrons
2) Compton scattering corrected by an inelastic form factor, S(q,Z)
Now a third possibility has been added, where both binding effects
and orbital motion of all electronic shells of all elements are
accounted for. This is particularly relevant for low energy photons
and/or heavy elements
How to activate: in order to activate the new fully detailed Compton
scattering treatment an EMFRAY card with WHAT(1)=4, (Rayleigh activated as
well) or WHAT(1)=6 (no Rayleigh) must be issued. Don't forget that EMFRAY
works on a region-by-region basis. For all problems where accuracy in the
physics treatment of sub-MeV photons is paramount, this option should
always be activated everywhere, for example by issuing:
EMFRAY 4.0 1.0 _at_LASTREG
Please note that the impact on CPU of the new feature is minimal in
almost all situations, therefore when in doubt activate it.
Extract from the release notes of Fluka2008.3 and other previous versions are
reported below.
=== Fluka2008.3 ====
Starting from this release, the code will be distributed in parallel to
the FLUKA web site by the Nuclear Energy Agency (NEA-OECD) Data Bank.
The NEA-OECD distribution (source included) will operate under the same
license and conditions, and following the procedures specific of NEA-OECD.
A completely revised version of the FLUKA web site will be available
starting September 26th. Users already registered should be flawlessly
migrated to the new system. Please, let us know through the fluka-discuss
list whichever problem you may meet.
- NEW PHYSICS AND TECHNICAL FEATURES -
Among the new features of this release (with respect to Fluka2006.3b):
- New neutron cross section library below 20 MeV, including 260 neutron
and 42 gamma groups: 31 neutron groups are thermal (1 in the previous
library). All neutron cross section data are freshly computed from the
most recent evaluated nuclear data files. Please note that the new 260
group library is now the default one (even though the "old" 72 group
one is still distributed). The transition energy between the group and
the model treatment for neutrons is now 20 MeV and no longer 19.6 MeV.
The default material temperature is now 296 K and no longer 293 K.
Please adapt your inputs accordingly
- New radioactive decay database, now including also conversion
electron and Auger lines
- Heavy ion pair production (optional, look at the PHYSICS card for
how to switch it on)
- New implementation of the BME model with vastly improved performances
for peripheral collisions. BME is available on request, please
contact Alfredo.Ferrari_at_cern.ch or Francesco.Cerutti_at_cern.ch
- An improved version of the PEANUT event generator which should significantly
improve residual nuclei predictions in the intermediate energy range, and
more in general should further improve predicted particle spectra
- The ability to convert particle fluences into various dose equivalent
quantities, previously possible by means of the special "user" routine
deq99c.f, has now been integrated into the code, using the generalized
particle type DOSE-EQ (240) (see below for practical instructions)
- New generalized particles:
* Dose (GeV/g) (DOSE, generalized particle id 228)
* Dose equivalent (pSv) (DOSE-EQ, generalized particle id 240)
* 1 MeV neutron Si equivalent fluence (for Silicon damage)
(SI1MEVNE, generalized particle id 236)
* High energy hadron fluence scoring (hadrons with energy larger than 20 MeV)
(HADGT20M, generalized particle id 237)
- New option AUXSCORE (see the manual for details):
* allows to restrict scoring to selected (generalized) particles,
for selected scoring estimators. It is a convenient way to
implement filters that formerly needed a comscw or fluscw
user routines. For instance, it can be used to score energy
deposition from a definite particle type, or to separately
score heavy ion fluences according to mass and/or atomic number
* allows to select the set of dose equivalent conversion factors to
be used for the calculation of DOSE-EQ. The default set used
AMB74, ambient dose equivalent from ICRP74 and Pelliccioni data.
For other available sets please refer to the manual.
!!! Please note that no coversion coefficient set is available !!!
!!! for heavy ions, so there will be no heavy ion contribution !!!
!!! to the dose equivalent !!!
- A new generator for neutrino interactions on nucleons and nuclei
has been developed and implemented in FLUKA, thanks to M.Lantz,
G.Smirnov, P.R.Sala, A.Ferrari, G.Battistoni. The neutrino-nucleon
event generator handles Deep Inelastic Scattering (NUNDIS), and
production of delta resonances (NUNRES). Hadronization after DIS is
handled by the same hadronization model used in hadron-hadron
interactions. NUNDIS and NUNRES are embedded into PEANUT to simulate
neutrino-nucleus reactions. Quasi-elastic neutrino interactions were
already simulated in PEANUT since 1997.
**** THIS IS A BETA VERSION **** of the neutrino generator. Some
functionalities are missing, errors and crashes are *NOT*
excluded. Users are invited to report any problem encountered to the
FLUKA developers.
Please note that :
* Neutrinos are discarded by default, therefore the user should issue a
DISCARD card with negative what's in order to un-discard them
* Only interactions by neutrinos as primary particles are
considered. Secondary neutrinos do not (re)interact.
* In order to request neutrino interactions the user should set them as
beam particles, using one of the names NEUTRIE...ANEUTRIT as SDUM.
* The user can restrict the simulations to a subset of the open
interaction channels, namely quasi-elastic, resonance, DIS and DIS
with charm production, in neutral current or charged current. This
selection can be performed through the PHYSICS card with SDUM=NEUTRINO.
By default, all reaction channels are simulated, with ratios depending
on the relative cross sections.
* Neutrino interactions are activated in "forced mode" : when a
neutrino primary particle is requested, the code forces a neutrino
interaction to occur in the point (or area) defined in the BEAMPOS
card.
* In this beta-release, charm production in neutral current reactions
is not implemented.
* In this beta release, the interaction rate does not depend on
the neutrino energy. This means that if the user requests a momentum
spread in the BEAM card, all neutrino momenta are sampled with the
same probability, disregarding the momentum dependency of the
total interaction cross section.
* With this beta release, the use of an user-written source for
neutrino interactions is possible, provided the following card
is added when a neutrino is loaded on the stack:
LFRPHN (NPFLKA) = .TRUE.
In this way, the neutrino will then be forced to interact at the
point specified as starting position in the source routine. In case
a spectrum of energies is input, it is the user task to properly
weigh the spectrum with the relevant neutrino cross sections (see
above point)
Already starting from Fluka2006.3, a new high energy event generator has
been developed, based on the sophisticated nuclear physics of PEANUT coupled
with the proved FLUKA Dual Parton Model description for hadron-hadron
collisions and a brand new Glauber cascade treatment. This model will
eventually substitute as default the old one (PEANUT is already the default
below 5 GeV). It is not yet the default, mostly because it requires a bit
more testing and cleaning up some FLUKA inconsistencies related to
quasi-elastic treatment. All thin target benchmarks of the code by the
development team are now run with the new model, the development of the old
one being frozen. The PHYSICS cards allows to switch on the new model (with
some caveats about the quasielastic issue) ie with:
PHYSICS 1000. 1000. 1000. 1000. 1000. 1000. PEATHRES
Please give particular attention to the PHYSICS card recommendations
(see below).
For all other features, please refers to the Fluka2006.3(b) release note
snippets reported at the end of these release notes.
=== Fluka2006.3(b) ===
The most relevant bug fixes or functionality improvements are listed below:
* LATTICE cards now accepts a mixture of (region) names and (lattice)
numbers in order to simplify lattice input (see
http://www.fluka.org/web_archive/earchive/new-fluka-discuss/0757.html )
* The memory allocations for the (maximum) numbers of irradiation intervals
and cooling times are now handled together, so that there is much
more flexibility when inputting a large number of irradiation intervals
(and relatively few cooling times) and viceversa. Small adjustments in
the usrsuwev program have been implemented because of this
* Creating a fluka.stop file inside the fluka_xxxx working directory
is going to stop the current run as it did in all previous release.
Starting from this release, if the file is instead named rfluka.stop,
not only the current run is stopped, but also the run sequence is
stopped even though the total requested number of runs has not yet
been achieved
* When scoring some types of "pointwise" energy depositions,
the JTRACK variable (common TRACKR) is set to a generalized particle
value:
JTRACK = 208 for non-transported nuclear recoils
JTRACK = 308 for low energy neutron kerma
JTRACK = 211 for EM particles produced below threshold
Values 208 and 211 were already set in past versions, while the 308 flag
is new. A new variable has been added in the TRACKR common to help identify
these energy depositions:
J0TRCK
it records the ID of the particle that originated the interaction.
Warning: this variable is normally set to 0, its value has a
meaning only when JTRACK = 208, 211, 308.
* A file, Version.tag, is included in the distribution in order to
simplify (semi)automatic procedures for identifying versions and
respins
* The heavy ion dE/dx at low energies (below 10-30 MeV/n for projectiles
of medium-large Z's) had a bug which slipped into the Fluka2005.6 release
and went unnoticed till now (thanks to Ercan Pilicer for pointing it
out), effectively disabling the effective Z algorithm.
All users who run heavy ion beams at low energies are warned to
moved immediately to Fluka2006.3b: results are now back to those of
Fluka200x, x=0,1,2,3,4 and in agreement with published benchmarks
* A couple of bugs were still lurking in the Birks law quenching
implementation when requested through the Mgdraw routine (thanks to
Vincenzo Patera for pointing out the problem). These bugs should have
affected only problems with magnetic field, however users who were
making use of this novel feature of Fluka2006.3 should better check
if their results are still the same. All users whose runs will stop
with the message
"FKBIRK, NONSENSE xxxxx CALL"
are warmly invited to contact us through fluka-discuss since the
messages could imply that problems are still around in the
Mgdraw-driven quenching implementation
* The prompt vs delayed radiation biasing selection through WHAT(4) of
the RADDECAY card was badly broken (thanks to Stefan Roesler for pointing
out this problem): now it is fixed and should behave as advertised
in the manual (feedback welcome)
Many other minor bug fixes have been implemented, but they should be
completely transparent to end users
A few further news of relevance for Fluka users are reported below:
* From this release on the support_at_fluka.org and physics_at_fluka.org mailing
addresses no longer exist. The messages sent to those addresses were
almost all about topics better discussed on fluka-discuss_at_fluka.org.
Whichever problem with the web site and/or the registration and download
procedures should be reported to the same list as well with possibly
[SUPPORT] at the beginning of the subject line
* A new list, fluka-users_at_fluka.org, has been created. All registered
Fluka users have been automatically subscribed to this list and new users
will be as well. This is a low traffic, one way only list, dedicated
to announcements (like a new release, a bug fixing respin, etc etc)
which are deemed to be relevant for all users. We strongly invite all
active Fluka users to not quit this list. Those no longer active, or
anyway whoever so wishes, can unsubscribe sending a message to
Majordomo_at_fluka.org "unsubscribe fluka-users" in the main body.
As usual, all active users are strongly encouraged to subscribe to
fluka-discuss_at_fluka.org
* A new very powerful tool for interacting with Fluka both at input
and output stages is now available, thanks to Vasilis Vlachoudis (CERN)
This tool, called Flair (FLuka Advanced Interface), can be downloaded
at
http://www.fluka.org/flair/index.html
This tool should run on whichever modern Linux distribution: users are
strongly encouraged to test it and provide their feedback through the
fluka-discuss list. All other tools, like FlukaGUI and TVF NMCRC, are
obviously still available via
http://www.fluka.org/Tools.html
The FLUKA development team
===== Fluka2006 ====
- NEW PHYSICS AND TECHNICAL FEATURES -
Among the new features of this release (with respect to Fluka2005.6):
- New "Input by name"(fully backcompatible with the past): particle,
materials, regions, generalized particles, binnings, and estimators can
now be indicated in the input file through their names rather than their
numbers. This new feature is compatible with the old input way: a mix of
name based and numeric values can be used in the input files. The
included example input file (example.inp) is now written "by name": the
traditional version (exfixed.inp) and a mixed one (exmixed.inp) are also
provided. See the manual for further details.
- New fission model/improvements to evaporation/fragmentation
* Actinide fission now done on first principles and no longer on
parametrized G_fiss/G_neu
* New fission barrier calculations following the most recent suggestions
by Myers & Swiatecki
* Fission level density enhancement at saddle point no longer
excitation energy independent but now washing out with excitation
energy coherently with the most recent studies and the recommendations
of a IAEA working group
* Fission product widths and asymmetric vs symmetric probabilities
better parametrized according to the most recent data/approaches
* New, energy dependent self-consistent, evaporation level densities
according to the IAEA working group recommendations
* New pairing energies consistent with the above point
* New mass tables including calculated masses besides exp. ones till
A=330. The use of masses calculated offline (available electronically)
with high reliability complex models allows, a) to extend to A larger
than those experimentally accessible, b) to minimize resorting to
empirical mass formulae online which often generate artefacts
* New shell corrections coherent with the new masses
The overall result in the residual predictions in the spallation zone
is a striking improvement for actinides (which was poor before), a nice
improvement for non-actinides (Pb, Au etc, it was already not bad),
and a global improvement in the mass distribution of fission fragments
for all of them. For non fissionable light-medium mass nuclei differences
are minor, nevertheless the new level densities appear to smooth out
some features and in particular some excessive odd-even effect
- An initial implementation of the BME model, available on request,
has been performed. It covers light ion interactions up to 100 MeV/n.
First results, when applied to positron emitter production with therapy
beams are encouraging
- Speed up of radioactive nuclei evolution
- Lattices: the required transformations can now be specified associating
each lattice with a specific roto-translation defined through
ROT-DEFI. This is a viable alternative to a user written lattic.f when
a limited number of transformations has to be defined. Both methods are
and will be fully supported, in principle the user can mix and use
predefined transformations for some lattices, and lattic.f for others.
See the manual (LATTICE card) for details
- An algorithm for parentheses optimization is now implemented in the
geometry package (contributed by V.Vlachoudis, see GEOBEGIN)
- Activity concentration 2D/3D binnings are now implemented through the
new generalized particle types ACTIVITY (234, activity per unit volume)
and ACTOMASS (235, activity per unit mass)
- Residual nuclei scoring and gas production: protons are now included
in the RESNUCLEi scoring, in order to prevent lazy users from
obtaining nonsense results on gas production (see below)
- Beta+/- spectra now include Coulomb and screening corrections
- Photomuon production is now implemented limited to coherent
(Bethe-Heitler) production for the time being (contributed by
S.Roesler/A.Fasso`). It can be activated by the PHOTONUC card
- Explicit primary ionization events can be requested on a material
basis. The user must provide the number of primary ionizations
per cm (and for some variants of the model a guess for the 1st ionization
potential) and choose one of the four available variants. Primary
ionization electron energies will then be stored inside common
ALLDLT at each step in the selected materials. It can be activated
by the IONFLUCT card. Use with care and possibly for gases only.
The number of primary ionizations can quickly escalate, particularly
when multiply charged ions are involved. No common saturation should
occur since the code is piling up all the remaining primary electrons
into the last common location if required, however CPU penalties can
be severe if used without wisdom
- Extension of PEANUT: last but not least, a new high energy event
generator has been developed, based on the sophisticated nuclear
physics of PEANUT coupled with the proved FLUKA Dual Parton Model
description for hadron-hadron collisions and a brand new Glauber
cascade treatment. This model will eventually substitute as default
the old one (PEANUT is already the default below 5 GeV). It is not
yet the default, mostly because it requires a bit more testing
and cleaning up some FLUKA inconsistencies related to quasi-elastic
treatment. All thin target benchmarks of the code by the development
team are now run with the new model, the development of the old one
being frozen. The PHYSICS cards allows to switch on the new model
(with some caveats about the quasielastic issue) ie with:
PHYSICS 1000. 1000. 1000. 1000. 1000. 1000. PEATHRES
-- OBSOLETE FEATURES --
- the COMMENT card is deprecated (ordinary comments starting with "*" are
of course supported): it is still accepted but there is no guarantee
it works properly
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Received on Mon Feb 12 2018 - 11:23:05 CET