=== Fluka-4.1.1 === BUG FIXES: - Fixed the issues reported in https://fluka-forum.web.cern.ch/t/run-aborts-with-stop-3500/1144 including two further single-precision-induced crashes in rQMD which led respectively to a non-positive center-of-mass momentum and an array index out of bounds. Additionally fixed a few rare crashes due to uninitialized nuclear spin and parity in the course of nucleus-nucleus collisions and electromagnetic dissociation involving exotic isotopes. - Fixed rare crashes in the aftermath of sub-150-MeV/n nucleus-nucleus interactions going through complete fusion for heavy isotopes: instead of failing to deal with these systems in FLUKA's pre-equilibrium module, the code now treats them directly through its evaporation module. - Fixed bookkeeping error in the propagation of spin and parity in inverse kinematics for nucleus-nucleus interactions such that the projectile nucleus is heavier than the target. - Handling of possible pathological light fragments returned by BME. - Fixed a rare crash due to a muon pair production event by a photon which led to a slightly negative target recoil energy. - If NOMORE is set different from zero in the source.f user routine, the total kinetic energy and the total primary weight are now correctly printed in the output file (they were off by the contribution of the discarded event before). - Fixed the DETECT card scoring crash reported in https://fluka-forum.web.cern.ch/t/detect-histogram-overflow-and-error-code-rc-144/1357 removing at the same time the "Detect: Histogram overflow" warnings formerly appearing when the deposited energy exceeded the upper limit of the DETECT-card histogram. === Fluka-4.1.0 === PHYSICS IMPROVEMENTS: - Spin and parity of the compound nucleus are now accounted for during the evaporation and Fermi break-up stages. - Photonuclear cross sections on 46Ti, 48Ti, 181Ta, and 208Pb have been slightly adjusted in the Giant-Dipole-Resonance region to remove spurious features. TECHNICAL IMPROVEMENTS: - An additional version of the source routine, source_newgen.f, with a cleaner structure that facilitates access to newcomers and several built-in options, has been made available as beta release in the src/user/ directory. (The traditional source.f is still fully operational and preexisting user-customized source routines remain totally compatible). - The usrmed.f user routine has now three additional arguments (TXXPOL, TYYPOL, and TZZPOL) carrying the particle polarization direction. - The sixth parameter (WHAT(6)) of the GLOBAL card, interpreted as REAL*8 units, now allows the user to customize the size of the blank common. - Prompt and decay electromagnetic transport thresholds, as possibly altered by the RADDECAY card, are now explicitly written in the output file. BUG FIXES: - As an unintentional side effect of the photofission restoring in 4.0, an excessive fission yield was reported for some material (e.g. Ta). This has now been cured. - The two crashes reported in https://fluka-forum.web.cern.ch/t/crash-with-index-error-and-floating-point-exception/879 have been solved. - In the SPOTBEAM card, flat angular divergences along X and Y directions appeared swapped and angles were misinterpreted as half-angles (instead of full angles). The respective corrections have been implemented. - The crash reported in https://fluka-forum.web.cern.ch/t/some-runs-are-failing-kaskad-reason-engw-0-ekres-0/1011 (due to an uninitialized variable in a low-energy proton reaction) has been solved. - Ions channelled in a bent-crystal now experience the suppression of large-angle single scattering, previously not active. - The angular distribution of photoelectrons generated by polarized photons has been restored. - Two rare PEANUT crashes, leading respectively to an index out of bounds and to an undefined particle mass, have been solved. - XSIZERO and AXSIZERO are no longer included in the HAD-CHAR generalized particle. - The rare crash reported in https://fluka-forum.web.cern.ch/t/ubchck-error-regarding/1098 (due to a misinitialized tolerance in USRBIN scoring) has been fixed. ========================================================================== === Fluka-4.0.1 === BUG FIXES: - Prevented USRBIN apportioned scoring of NET-CHRG, RES-NUCL, and annihilation at rest of positrons (all are point-like quantities). - Now stopping (instead of looping forever) for empty input file. - Fixed optical photon crash. - Fixed rare crash in rQMD leading to an index out of bounds error. - Fixed rare crash in rQMD leading to zero center-of-mass momentum. - Fixed index-out-of-bounds in usysuw.f and raised the maximum number of first-quantity bins to 5000. - Fixed bug in USRBIN scoring which resulted in zero by-region scoring. - Fixed bug in SPOTTRAN: handling of transformation #2. - In the crystal tracking module, corrected a missing factor Z (projectile charge) when the electrostatic potential is calculated in the volume zone for ions. - When computing the electrostatic potential for a charged particle in a crystal volume zone, the contributions from the charge distribution of the four nearest crystal planes are now considered (instead of just the two nearest planes). - Lifted an excessively cautious abort in case of nuclear cross-section was not initialized for new particle species resulting from ion fragmentation in the crystal channeling module. - Lifted condition which inhibited the dechanneling in case of volume captured particles in the crystal channeling module. === Fluka-4.0.0 === PHYSICS IMPROVEMENTS: - Charged particle transport in electric fields has been implemented, as far as vacuum regions are concerned. See the ELCFIELD card and the src/user/elefld.f user routine. - Anisotropic effects in crystals have been modeled for positively charged particles, including channeling, dechanneling, volume reflection and volume capture. See the CRYSTAL card. - Electronuclear reactions have been enabled. See the PHOTONUC card with SDUM = ELECTNUC. The Electric Quadrupole (E2) contribution to the virtual photon spectrum, applying also to muon photonuclear reactions and ion electromagnetic dissociation, has been added. - Direct (p,n) reactions to the Isobaric Analogue State of several target isotopes (27Al, 40Ar, 42,44,48Ca, 51V, 90Zr, 120Sn, 208Pb, 209Bi) have been implemented and substantially improved (7Li and 9Be) from threshold up to a few hundred MeV, accounting for monoenergetic peaks in the emitted neutron spectrum and yielding a particular improvement for 7Li and 9Be at forward angles. - The near to threshold treatment of alpha reaction cross sections has been refined. Moreover, reaction cross sections of alpha particles on light nuclei (12C and 16O) have been corrected around the 1-GeV minimum so as to improve the agreement with experimental data in F. Horst et al., PhysRevC 96 024624 (2017) and F. Horst et al., PhysRevC 99 014603 (2019). - The BME event generator, describing ion-ion interactions below 150 MeV/n, has been interfaced to the PEANUT pre-equilibrium for cases outside the domain of the pre- computed BME database, yielding a particular improvement for the excitation functions of heavy residues produced by low energy alphas. Moreover, it has been extended to 3He and 3H induced reactions (on A>5 nuclei). - The RQMD event generator, describing ion-ion interaction between 0.1 and 5.5 GeV/n (partially overlapping the BME and DPMJET energy ranges), has been interfaced to the PEANUT pre-equilibrium, prior to the final de-excitation stage of hot fragments, improving its accuracy. - Photofission has been eventually restored, including electron and positron photonuclear reactions. - (Anti)Neutrino cross sections have been revised. TECHNICAL IMPROVEMENTS: - Parenthesis expansion in region definitions is evaluated runtime, if it results in too many terms at initialization. - A spatially distributed source can be defined from a USRBIN output file by means of the new SDUM = BIN-SOUR of the SPECSOUR card. - Multiple beam spots can be defined by means of the SPOTBEAM, SPOTDIR, SPOTPOS and SPOTTRAN cards, allowing treatment planning system simulations. - Dynamic memory allocation has been implemented. E.g. scoring grids requiring more memory than the default memory block reserved by FLUKA, which led to a program halt in earlier versions, are now automatically accommodated for (as long as sufficient RAM is available). BUG FIXES: - Typo correction in the neutrino interaction package. - Corrected check of perpendicularity of REC axes. - Corrected missing substitution of user defined variables in body continuation lines. - Corrected rare crash in invariant mass check in the DPM interface. - Corrected scoring of the generalized particles ALPHA-D and SQBETA-D. ========================================================================== === Fluka2011.3 === All FLUKA versions older than Fluka2011.2x.8 (included) are not compatible with the present release distributed by CERN and will no longer be supported. No debugging/maintenance/assistance will be provided for older versions. The download and use of the FLUKA package distributed by CERN are governed by a new license, which is available in the package. Support for the present release is available from http://fluka.cern and/or http://cern.ch/fluka-forum To propose modifications to the FLUKA source files, you can send a request fluka.team@cern.ch BUG FIXES AND TECHNICAL UPDATES: - The package structure has been completely changed (see the INSTALL for a description of the FLUKA structure) - The name of the include files has changed (by removing the parentheses and adding the extension .inc). A python script fluka_src_converter.py, located in the bin directory, can be used to convert source files with the old convention of the include file name, - No environment variables are needed to compile, link and run FLUKA executable - A PEANUT bug, resulting in the error message NO CHANNEL SELECTED, has been fixed - A bug in electromagnetic dissociation, resulting in an abort at ion-ion collision energies above the LHC ones, has been fixed ========================================================================== Extracts from the release notes of Fluka2011.2x and other previous versions are reported below. === 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 plethora 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. 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. 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 Ph.D. work of Anatoli Fedynitch, and it has been benchmarked against LHC data, showing significantly better reproduction of experimental data at center-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 From Fluka2011.2x.8 on: - A new DAMAGE default for damage (DPA) calculations is now available - The TPSSCORE and RAD-BIOL cards for radiobiological linear-quadratic alpha/beta scoring are available (see the ASCII manual for further details) - The generalized particles 'RES-NUCL', 'DOSE-H2O', 'ALPHA-D ', 'SQBETA-D', 'LGH-IONS', 'HVY-IONS', 'E+E-GAMM', 'ANNIHRST' have been added - The IAZTRK flag in TRACKR allows for tagging products of a given radioisotope - AUXSCORE filtering is now available for resnuclei USRBIN's - The ability to change into whichever material for decay product transport (limited before to vacuum or blackhole) is now implemented - A protection against "impossible" isotopes requested with the MATERIAL card has been implemented From Fluka2011.2x.6 on: - A special source for synchrotron radiation is now available. It can be activated with the SPECSOUR card, SDUM=SYNC-RAD or SYNC-RDN or SYNC-RAS, or SYNC-RDS. Detailed instructions are available in the manual. - Optical photons can now be input in a user written source routine. They can be used in source as any other particle, using the particle id -1 (ILOFLK (NPFLKA)=-1). Fluka then takes care of moving them to the optical photon stack and to track them. Of course, as usual, the optical properties of the various media must be provided by the user with the relevant OPT-PROP option 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 - The SDUM=IONSPLIT workaround in the PHYSICS card has been modified in fluka2011.2x, in order to prevent unphysical features in proton/neutron spectra when run with WHAT(6)=0/1. WHAT(6)=0 is now deprecated and must be avoided if rQMD/DPMJET-3 are not linked. Indeed a protection has been implemented starting from Fluka2011.2x.4. A new, more physically sound, option, WHAT(6)=3, is available in Fluka2011.2x. The best choice, and the recommended setup, is to link rQMD and Dpmjet-3, and set: PHYSICS 1.0 0.005 0.15 2.0 3.0 3.0IONSPLIT Still, keep in mind that this is only a rough workaround waiting for a native model for deuteron interactions below 150 MeV/n - Separators in FREE format: the "/" separator in free format input has been removed and substituted by the "%" one in order to avoid confusion with the mathematical operator. The other separators, ";", ",", "\", ":" are unchanged - Execution script rfluka: the rfluka script used to launch Fluka has been slightly modified since now the code opens the input file through a name exported by the script rather than through a pipe. Old rfluka scripts will no longer work with Fluka2011.2x.4 -- 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 an 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. - The ARB, BOX, WED body types, which are deprecated since many years due to their precision problem-prone coding, are now accepted only if the user explicitly sets SDUM=DEPRBODY in the GLOBAL card. They will disappear entirely with the next full release. The same geometrical shapes can be obtained in a safer way using a combination of the other body types and of transformations. === 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 input 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 were 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 === Fluka2011.2b === This release contains a few small fixes, one of critical importance for DPA calculations, and a significant functional 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 information 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 information according to a Hounsfield number to material/density translation algorithm which can be tuned by the user. === 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. New features: - 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 contribution 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 materials 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 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. === 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 === Fluka2008.3b === New functionality: - Compton scattering with full account 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 @LASTREG Please note that the impact on CPU of the new feature is minimal in almost all situations, therefore when in doubt activate it. === Fluka2008.3 === - 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 fill a contact form at https://fluka.cern/contact - 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 conversion 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 dependence 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 here. === 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 * 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 vice-versa. 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 === 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