Download The MARS Code System User`s Guide Version 15(2014)

IND(11)=T adds the φ− dimension to the Standard (r-z) Geometry zones, giving an azimuthal
structure to the accumulation of the results. The user must specify the number and
size of the azimuthal zones via the NAZM and AZIM data cards.
IND(11)=F no azimuthal divisions in the Standard Geometry zones.
IND(12)
reserved for the point-kernel option to calculate residual radioactivity with routine
MARACT; not implemented in this version.
IND(13)=T switch on the use of the M AD -M ARS beam line builder MMBLB interfaced with the
MAD lattice description, and define histograms, using user subroutines MARS2BML
and BML2MARS.
IND(13)=F MMBLB is not activated.
IND(14)=T User subroutines ALIGN, SAGIT and RFCAVT are called by the M ARS geometry
description software modules.
IND(14)=F The above subroutines are not called.
IND(15)=T Enables a “global parameter set for thick shielding”. The set consists of various
physics options, energy thresholds, and tabulation options which are collectively appropriate when modeling thick shielding. Setting this flag can provide a substantial
CPU-time saving for models of thick extended shielding. The particular parameters
and their settings are given in Table 6. As with all similar global settings, any of the
individual parameters in this set can be re-set, globally or for specific materials, using
the appropriate input deck parameter. This mode is especially powerful if used in conjunction with IND(6)=T with the neutron threshold energy EMNEU ≥ 10−4 GeV. Be
careful with using IND(6)=T in this mode if the neutron threshold energy EMNEU
is below 10−4 GeV, because of a possible substantial increase of the CPU-time per
history. As always, do a short timing test first.
IND(15)=F The above items in the ”global parameter set for thick shielding” are set to standard
MARS defaults.
IND(16)=T MCNP style geometry description is used, via entries in the MCNP section of the
MARS.INP file, and with IND(5)=T.
IND(16)=F MCNP geometry description is not used.
IND(17)=T Enables algorithms for accurate modeling of Displacement-per-Atom (DPA) distributions and histograms. These algorithms are valid only if the threshold energies of charged particles in matter, EMCHR and EMIEL and corresponding materialdependent values of the MTCH and MTEL cards, are below EDP Ath = 0.005 GeV.
That is why the threshold energies for charged particles are converted to EDP Ath if
they exceed EDP Ath and IND(17)=T.
IND(17)=F The DPA algorithms are not activated, and DPA distributions and histograms are not
calculated.
IND(18)=T Not used currently.
IND(18)=F Not used currently.
IND(19)=T Enables the ROOT system geometry and visualization mode.
IND(19)=F The ROOT system geometry and visualization mode is not activated.
4.2.2
Run Control – CTRL, RZVL, NEVT, SEED, SMIN, VARS, UCTR
CTRL IVIS IEVT IVOL IHIS IDTR
Integer variables which control running modes: the normal Monte Carlo session, GUI visualization mode, “stand-alone” event generator mode, and volume calculation mode. Each of these is
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