From 7dfcc480ba1e19bd3232349fc733caef94034292 Mon Sep 17 00:00:00 2001
From: stainer_t <thomas.stainer@oecd-nea.org>
Date: Mon, 8 Sep 2025 13:48:49 +0200
Subject: Initial commit from Polytechnique Montreal

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+\subsection{The {\tt LIB:} module}\label{sect:LIBData}
+
+The general format of the input data for the \moc{LIB:} module is the following:
+
+\vspace{-0.2cm}
+
+\begin{DataStructure}{Structure \dstr{LIB:}}
+\dusa{MICLIB} \moc{:=} \moc{LIB:} $[$ \dusa{MICLIB} $]~[~\{$ \dusa{MICRHS} $|$ \dusa{MACRHS} $|$ \dusa{EVORHS} $\}~]$ 
+\moc{::} \dstr{desclib}
+\end{DataStructure}
+
+\vspace{-0.6cm}
+
+\noindent
+where
+
+\begin{ListeDeDescription}{mmmmmmmm}
+
+\item[\dusa{MICLIB}] {\tt character*12} name of the \dds{microlib} that will contain the internal
+library. If \dusa{MICLIB} appears on both LHS and RHS, it is updated; otherwise, it is created. 
+
+\item[\dusa{MICRHS}] {\tt character*12} name of a read-only \dds{microlib} data structure used by the
+\moc{CATL} or \moc{MAXS} option of \Sect{desclib}.
+
+\item[\dusa{MACRHS}] {\tt character*12} name of a read-only \dds{macrolib} data structure to be included
+directly in \dusa{MICLIB} before updating it.
+
+\item[\dusa{EVORHS}] {\tt character*12} name of a read-only \dds{burnup} data structure used by the
+\moc{BURN} option of \Sect{desclib}. The number densities for the isotopes in file \dusa{MICLIB}
+will be replaced selectively by those found in \dusa{EVORHS}.
+
+\item[\dstr{desclib}] input structure for this module (see \Sect{desclib}).
+
+\end{ListeDeDescription}
+
+\subsubsection{Data input for module {\tt LIB:}}\label{sect:desclib}
+
+In the case where \dusa{MICRHS} is absent or represents a \dds{macrolib}, \dstr{desclib} takes the form:
+
+\begin{DataStructure}{Structure \dstr{desclib}}
+$[$ \moc{EDIT} \dusa{iprint} $]$ \\
+$[$ \moc{NGRO} \dusa{ngroup} $]$ \\
+$[$ \moc{MXIS} \dusa{nmisot} $]$ \\
+$[$ \moc{NMIX} \dusa{nmixt} $]$ \\
+$[$ \moc{CALENDF} \dusa{ipreci} $]$ \\
+$[$ \moc{CTRA} $\{$ \moc{NONE} $|$ \moc{APOL} $|$ \moc{WIMS} $|$ \moc{OLDW} $|$ \moc{LEAK} $\}$ $]$
+$[$ \moc{ANIS}  \dusa{naniso} $]$ \\
+$[$ \moc{STERN} \dusa{nstern} $]$ \\
+$[$ \moc{ADJ} $]~[$ \moc{PROM} $]$ \\ 
+$[~\{$ \moc{CDEPCHN} $|$ \moc{RDEPCHN} $\}~]$ \\
+$[~\{$ \moc{SKIP} $|$ \moc{INTR} $|$ \moc{SUBG} $|$ \moc{PT} $|$ \moc{PTMC} $|$ \moc{PTSL} $|$ \moc{RSE} $[$ \dusa{svdeps} $]~|$ \moc{NEWL} $\}~]$ $[$
+\moc{MACR} $]$\\ 
+$[$ \moc{ADED} \dusa{nedit}  ( \dusa{HEDIT}(i), i=1,\dusa{nedit} ) $]$  \\
+$[$ \moc{DEPL} $\{$ \moc{LIB:} $\{$ \moc{DRAGON} $|$ \moc{WIMSD4} $|$ \moc{WIMSE} $|$ \moc{WIMSAECL} $|$ \moc{NDAS} $|$ \moc{APLIB3} $\}$ \moc{FIL:} \dusa{NAMEFIL} \\
+\hskip 0.6cm $|$ \moc{LIB:} $\{$ \moc{APLIB2} $|$ \moc{APXSM} $\}$ \moc{FIL:} \dusa{NAMEFIL} \dstr{descdeplA2} \\
+\hskip 0.6cm $|$ \dusa{ndepl} \dstr{descdepl} $\}$ $]$ \\
+$[[$ \moc{MIXS} \moc{LIB:} \\
+\hskip 0.6cm  $\{$ \moc{DRAGON} $|$ \moc{MATXS} $|$ \moc{MATXS2} $|$
+                  \moc{WIMSD4} $|$ \moc{WIMSE} $|$ \moc{WIMSAECL} $|$ \moc{NDAS} $|$    
+                  \moc{APLIB1} $|$ \moc{APLIB2} \\
+\hskip 0.85cm  $|$ \moc{APXSM} $|$ \moc{APLIB3} $|$ \moc{MICROLIB} $\}$ \\
+\hskip 0.6cm  \moc{FIL:} \dusa{NAMEFIL} $[[$ \dstr{descmix1} $]]$ $]]$ \\
+{\tt ;}
+\end{DataStructure}
+
+\noindent It is possible to reset an existing  \dds{microlib} (i.e., \dusa{MICLIB} is present
+in both the LHS and RHS) and to reprocess all the isotopes from the cross section libraries.
+In this case, \dstr{desclib} takes the simplified form:
+
+\begin{DataStructure}{Structure \dstr{desclib}}
+$[$ \moc{EDIT} \dusa{iprint} $]$ \\
+$\{$ \moc{INTR} $|$ \moc{SUBG} $|$ \moc{PT} $|$ \moc{PTMC} $|$ \moc{PTSL} $|$ \moc{RSE} $[$ \dusa{svdeps} $]~|$ \moc{NEWL} $\}~[$ \moc{MACR} $]$ \\ 
+\moc{MIXS} \\
+{\tt ;}
+\end{DataStructure}
+
+\noindent
+If keyword \moc{CATL} is given, \dusa{MICLIB} is catenated with the RHS \dusa{LIBRHS} \dds{microlib} .
+
+\begin{DataStructure}{Structure \dstr{desclib}}
+$[$ \moc{EDIT} \dusa{iprint} $]$ \\
+$[$ \moc{MXIS} \dusa{nmisot} $]$ \\
+$[$ \moc{NMIX} \dusa{nmixt} $]$ \\
+$[~\{$ \moc{SKIP} $|$ \moc{MACR} $\}~]$
+$[~\{$ \moc{CDEPCHN} $|$ \moc{RDEPCHN} $\}~]$ \\
+$[$ \moc{DEPL} $\{$ \moc{LIB:} $\{$ \moc{DRAGON} $|$ \moc{WIMSD4} $|$ \moc{WIMSE} $|$ \moc{WIMSAECL} $|$ \moc{NDAS} $|$ \moc{APLIB3} $\}$ \moc{FIL:} \dusa{NAMEFIL} \\
+\hskip 0.6cm $|$ \moc{LIB:} $\{$ \moc{APLIB2} $|$ \moc{APXSM} $\}$ \moc{FIL:} \dusa{NAMEFIL} \dstr{descdeplA2} \\
+\hskip 0.6cm $|$ \dusa{ndepl} \dstr{descdepl} $\}$ $]$ \\
+\moc{CATL} $[[$ \dstr{descmix2} $]]$ \\
+{\tt ;}
+\end{DataStructure}
+
+\noindent
+Alternatively if keyword \moc{BURN} or \moc{MAXS} is given, \dstr{desclib} takes the form:
+
+\begin{DataStructure}{Structure \dstr{desclib}}
+$[$ \moc{EDIT} \dusa{iprint} $]$ \\
+$\{$ \moc{BURN} $\{$ \dusa{iburn} $|$ \dusa{tburn} $\}~|$ \moc{MAXS} $\}$
+$[[$ \dstr{descmix2} $]]$ \\
+{\tt ;}
+\end{DataStructure}
+\noindent where the RHS data structure is a \dds{burnup} (\dusa{EVORHS}) or a \dds{microlib} (\dusa{LIBRHS}) data structure. \dstr{desclib} options are:
+
+\begin{ListeDeDescription}{mmmmmm}
+
+\item[\moc{EDIT}] keyword used to modify the print level \dusa{iprint}.
+
+\item[\dusa{iprint}] index used to control the printing in this operator. It
+must be set to 0 if no printing on the output file is required while values
+$>$0 will increase in steps the amount of information transferred to the output
+file. If \dusa{iprint}$\ge$10, the depletion chain is printed in the format of
+structure \dstr{descdepl}. If \dusa{iprint}$\ge$20, the depletion chain is also
+printed in the format of structure \dstr{descdeplA2}.
+
+\item[\moc{MXIS}] keyword used to redefine the maximum number of isotopes per
+mixture.  
+
+\item[\dusa{nmisot}] the maximum number of isotopes per
+mixture. By default up to 300 different isotopes per mixture are permitted.
+
+\item[\moc{NMIX}] keyword used to define the number of material mixtures. This
+data is required if \dusa{MICLIB} is created.
+
+\item[\dusa{nmixt}] the maximum number of mixtures (a mixture
+is characterized by a distinct set of macroscopic cross sections). 
+
+\item[\moc{CALENDF}] keyword to set the accuracy of the CALENDF probability
+tables.
+
+\item[\dusa{ipreci}] integer set to 1, 2, 3 or 4. The highest the value, the
+more accurate are the probability tables. The default value is \dusa{ipreci}=4.
+
+\item[\moc{CTRA}] keyword to specify the type of transport correction that
+should be generated and stored on the \dds{microlib}. The transport correction is to be
+substracted from the total and isotropic ($P_0$) within-group scattering cross sections. A leakage correction, equal 
+to the difference between current-- and flux--weighted total cross sections ($\sigma_{1}-\sigma_{0}$)
+is also applied in the \moc{APOL}, \moc{OLDW} and \moc{LEAK} cases. All the operators that
+will read this \dds{microlib} will then have access to transport corrected
+cross sections. The default is no transport correction.
+
+\item[\moc{NONE}] keyword to specify that no transport correction should be
+used in this calculation.
+
+\item[\moc{APOL}] keyword to specify that an APOLLO type transport correction
+based on the linearly anisotropic ($P_1$) within-group scattering cross sections is to be set. This correction assumes that
+the micro-reversibility principle is valid for all energy groups. This type of
+correction uses $P_1$ scattering information present on the library.
+
+\item[\moc{WIMS}] This type of correction uses directly a transport-correction
+provided on the library.
+Such information is available in WIMSD4, WIMSE and WIMS--AECL libraries. This is
+the new recommended option with WIMS-type libraries. {\sl This option has no effect on
+libraries that does not contain transport correction information.}
+
+\item[\moc{OLDW}] keyword to specify that a WIMS type transport
+correction based on the $P_1$ scattering cross sections is to be
+set. This correction
+assumes that the micro-reversibility principle is valid only for groups energies
+less than 4.0 eV. For the remaining groups a $1/E$ current spectrum is considered
+in the evaluation of the transport correction. This type of correction uses
+$P_1$ scattering information present on the library.
+
+\item[\moc{LEAK}] A leakage correction is applied to the total and
+$P_0$ within-group scattering cross sections. No transport correction is 
+applied in this case.
+
+\item[\moc{ANIS}] keyword to specify the maximum level of anisotropy for the
+scattering cross sections.
+
+\item[\dusa{naniso}] number of Legendre orders for the representation of the
+scattering cross sections. Isotropic scattering is represented by
+\dusa{naniso}=1 while  \dusa{naniso}=2 represents linearly anisotropic
+scattering. Generally the linearly anisotropic ($P_1$) scattering contributions are
+taken into account via the transport correction (see \moc{CTRA} keyword) in the
+transport calculation. For $B_{1}$ or $P_{1}$ leakage calculations, the linearly
+anisotropic scattering cross sections are taken into account explicitly.  The
+default value is \dusa{naniso}=2.
+
+\item[\moc{STERN}] keyword to specify the application of the Sternheimer density correction for charged particles.
+
+\item[\dusa{nstern}] index used to control the Sternheimer correction application. Sternheimer correction applied for both restricted total stopping power
+and heat deposition cross section ({\tt H-FACTOR}) is represented by \dusa{nstern} $=1$. A complete desactivation of the Sternheimer correction is obtained
+by setting \dusa{nstern} $=0$. By default, the Sternheimer density correction is applied for both quantities. Notes: 1) The Sternheimer density correction should be
+applied for both quantities except for specific charged particles cross sections perturbations analysis; 2) The Sternheimer density correction should be
+applied on macroscopic cross sections. However, the heat deposition cross section contains a microscopic collisional stopping power which has not been
+corrected in ELECTR module of NJOY. This is why the charged particle {\tt H-FACTOR} data $-$ recovered from microscopic libraries produced by ELECTR, but not
+those produced by CEPXS-BFP $-$ should be corrected in DRAGON5.
+
+\item[\moc{ADJ}] keyword to specify the production of adjoint macroscopic
+cross sections. By default, direct cross sections are produced.
+
+\item[\moc{PROM}] keyword to specify that prompt neutrons are to be considered
+for the calculation of the fission spectrum. By default, the contribution due to
+delayed neutrons is considered. This option is only compatible with a
+\moc{MATXS} or \moc{MATXS2} format library.
+
+\item[\moc{CDEPCHN}] keyword to enable the automatic completion of burnup chains.
+
+\item[\moc{DDEPCHN}] keyword to avoid the automatic completion of burnup chains.
+
+\item[\moc{SKIP}] keyword to recover the user--defined microlib data without processing
+any library (i.e., without temperature and/or dilution interpolation).
+
+\item[\moc{INTR}] keyword to perform a temperature and dilution interpolation
+of the microscopic cross sections present in the libraries. The bin-type
+cross-section data is not processed. This is the default option.
+
+\item[\moc{SUBG}] keyword to activate the calculation of the physical probability
+tables using the tempera\-tu\-re-interpolated cross-section data as
+input.\cite{subg,nse2004} The bin-type cross-section data is not processed.
+
+\item[\moc{PT}] keyword to activate the calculation of the CALENDF-type
+mathematical probability tables ({\sl without} slowing-down correlated weight matrices)
+using the bin-type cross-section data as input.\cite{pt} This option is
+compatible with the Sanchez-Coste self-shielding method and with the subgroup projection method (SPM).\cite{SPM09}
+
+\item[\moc{PTMC}] this option is similar to the \moc{PT} procedure. Here, the base points of the probability tables corresponding
+to fission and scattering cross sections and to components of the transfer scattering matrix are also obtained using the CALENDF approach.
+
+\item[\moc{PTSL}] keyword to activate the calculation of the CALENDF-type
+mathematical probability tables and slowing-down correlated weight matrices
+using the bin-type cross-section data as input.\cite{nse2004}
+
+\item[\moc{RSE}] keyword to activate the generation of information for the resonance spectrum expansion (RSE) method.\cite{rse2021}
+
+\item[\dusa{svdeps}] rank accuracy $\epsilon_{\rm svd}$ of the singular value decomposition. Singular values $w_i \le \epsilon_{\rm svd}\Delta u_{\rm elem}$ are set to zero.
+$\Delta u_{\rm elem}$ is the elementary lethargy width of the Autolib. The default value is \dusa{svdeps}=1.0 $\times 10^{-3}$.
+
+\item[\moc{NEWL}] keyword to activate the calculation of a microlib
+containing temperature-interpo\-la\-ted cross-section data. The bin-type
+cross-section data is also interpolated. Probability tables are not computed.
+
+\item[\moc{MACR}] keyword to force the calculation of the embedded
+macrolib. By default, the embedded macrolib is computed, {\sl except if} one of the
+key words \moc{SKIP}, \moc{INTR}, \moc{SUBG}, \moc{PT} or \moc{NEWL} is used.
+
+\item[\moc{ADED}] keyword to specify the input of additional cross sections to
+be treated by DRAGON. These cross sections are not needed to solve the transport
+equation but are recognized by the \moc{EDI:} and utility operators.
+
+\item[\dusa{nedit}] number of types of additional cross sections.
+
+\item[\dusa{HEDIT}] {\tt character*6} name of an additional
+cross-section type. This name also corresponds to vectorial reactions in a
+\moc{MATXS} and
+\moc{MATXS2} format library. For example:
+
+\moc{NWT0}/\moc{NWT1}=$P_0/P_1$ library weight functions.\\
+\moc{NTOT0}/\moc{NTOT1}=$P_0/P_1$ neutron total cross sections.\\
+\moc{NELAS}=Neutron elastic scattering cross sections (MT=2).\\
+\moc{NINEL}=Neutron inelastic scattering cross sections (MT=4).\\
+\moc{NG}=Neutron radiative capture cross sections (MT=102).\\
+\moc{NFTOT}=Total fission cross sections (MT=18).\\
+\moc{NUDEL}=Number of delayed secondary neutrons (Nu-D / MT=455).\\
+\moc{NFSLO}=$\nu*$slow fission cross section.\\
+\moc{NHEAT}=Heat production cross section.\\
+\moc{CHIS}/\moc{CHID}=Slow/delayed fission spectrum.\\
+\moc{NF}/\moc{NNF}/\moc{N2NF}/\moc{N3NF}=$\nu*$partial fission cross sections (MT=19, 20, 21 and 38).\\ 
+\moc{N2N}/\moc{N3N}/\moc{N4N}=(n,2n), (n,3n), (n,4n) cross sections (MT=16, 17 and 37).\\
+\moc{NP}/\moc{NA}=(n,p) and (n,$\alpha$) transmutation cross sections (MT=103 and 107).
+
+By default, DRAGON will always attempt to recover the additional cross sections
+\moc{NG}, \moc{NFTOT}, \moc{NHEAT} and \moc{N2N} which are required for the depletion
+calculations. 
+
+\item[\moc{DEPL}] keyword to specify that the isotopic depletion (burnup)
+chain is to be read. For a given \moc{LIB:} execution only one isotopic
+depletion chain can be read. 
+
+\item[\moc{MIXS}] keyword to specify that the mixture description is to be
+read. For a given \moc{LIB:} execution more than one cross-section library can
+be read. 
+
+\item[\moc{LIB:}] keyword to specify the type of library from which the
+isotopic depletion chain or microscopic cross section is to be read. It is
+optional when preceded by the keyword \moc{DEPL} in which case the isotopic
+depletion chain is read from the standard input file. 
+
+\item[\moc{DRAGON}] keyword to specify that the isotopic depletion chain or
+the microscopic cross sections are in the {\sc draglib} format.
+
+\item[\moc{MATXS}] keyword to specify that the microscopic cross sections are
+in the MATXS format of NJOY-II and NJOY-89 (no depletion data available for
+libraries using this format).
+
+\item[\moc{MATXS2}] keyword to specify that the microscopic cross sections are
+in the MATXS format of NJOY-91 (no depletion data available for libraries using
+this format). The MATXS file is a binary sequential file by default. If the name
+\dusa{NAMEFIL} has a leading ``{\tt \_}'' character, the MATXS file is expected to be
+BCD-formatted, as produced by NJOY.
+
+\item[\moc{WIMSD4}] keyword to specify that the isotopic depletion chain and the
+microscopic cross sections are in the WIMSD4 format, as produced by module {\tt wimsr} of NJOY with flag
+{\tt iverw} $=4$. This format is supported by the WLUP project.\cite{wlup}
+
+\item[\moc{WIMSE}] keyword to specify that the isotopic depletion chain and the
+microscopic cross sections are in the WIMSE format, as produced by module {\tt wimsr} of NJOY with flag
+{\tt iverw} $=5$.
+
+\item[\moc{WIMSAECL}] keyword to specify that the isotopic depletion chain and the
+microscopic cross sections are in the WIMS-AECL format.
+
+\item[\moc{NDAS}] keyword to specify that the isotopic depletion chain and the
+microscopic cross sections are in the NDAS format, as used in recent versions of WIMS-AECL.
+
+\item[\moc{APLIB1}] keyword to specify that the microscopic cross sections are
+in the APOLLO-1 format. There are no depletion chains available for libraries using this
+format.
+
+\item[\moc{APLIB2}] keyword to specify that the microscopic cross sections are
+in the APOLLO-2 direct access format. There are no depletion chains available for libraries
+using this format. However, fission yields, radioactive decay constants and
+energy released per fission or radiative capture are recovered from the file.
+Only versions of the APOLIB-2 libraries subsequent or equal to CEA93-V4 can be
+processed. The list of isotopes (standard and self-shielded) available in an APOLIB-2
+is printed by setting the print flag to a value \dusa{iprint}$\ge$10.
+
+\item[\moc{APXSM}] keyword to specify that the microscopic cross sections are
+in the APOLIB-XSM format, the output format of N2A2 utility. There are no depletion chains available for libraries
+using this format. However, fission yields, radioactive decay constants and
+energy released per fission or radiative capture are recovered from the file.
+The list of isotopes (standard and self-shielded) available in an APOLIB-XSM
+is printed by setting the print flag to a value \dusa{iprint}$\ge$10.
+
+\item[\moc{APLIB3}] keyword to specify that the microscopic cross sections are
+in the APOLIB-3 format, the output format of the Galilee system. An ENDF/B evaluation is
+represented by three HDF5 files:
+\begin{description}
+\item[\dusa{NAME1}:] HDF5 file containing infinite dilution information
+\item[\dusa{NAME2}:] HDF5 file containing resonance self-shielding information
+\item[\dusa{NAME3}:] HDF5 file containing depletion chains, branching ratio, fission yields and energy deposition information.
+\end{description}
+After \moc{DEPL}, the \moc{FIL:} keyword is followed by the concatenation of \dusa{NAME1} and \dusa{NAME3} with a colon character ({\tt :}) between
+the two names. After \moc{MIXS}, the \moc{FIL:} keyword is followed by the concatenation of \dusa{NAME1} and \dusa{NAME2} with a colon character ({\tt :}) between
+the two names. The list of isotopes (standard and self-shielded) available in an APOLIB-3
+is printed by setting the print flag to a value \dusa{iprint}$\ge$10.
+
+\item[\moc{MICROLIB}] keyword to specify that the microscopic cross sections are
+in a {\sc microlib}-formatted object, as produced by DRAGON. This format is similar to the {\sc draglib}
+format where the isotopes are stored in elements of list {\tt ISOTOPESLIST} instead of been stored
+as independent sub-directories.
+
+\item[\moc{FIL:}] keyword to specify the name of the file where is stored the
+isotopic depletion data. 
+
+\item[\dusa{NAMEFIL}] {\tt character*64} name of the library
+where the isotopic depletion chain or the microscopic cross sections are stored.
+
+Library names in {\sc draglib} format are limited to 12 characters.
+
+An \moc{APLIB3} library name is the concatenation of two names with a colon character ({\tt :}) between them:
+\begin{verbatim}
+  DEPL LIB: APLIB3 FIL: CLA99CEA93:CLA99CEA93_EVO
+  MIXS LIB: APLIB3 FIL: CLA99CEA93:CLA99CEA93_SS
+\end{verbatim}
+
+A \moc{NDAS} library is made of two or more files. These file names must be concatenated in a single
+\dusa{NAMEFIL} name, using colons as separators. The {\sc ascii} index file is always the first,
+followed by optional patch files, and terminated by the main direct-access binary file. The
+following sample data line corresponds to a {\sc ndas} library without patch:
+\begin{verbatim}
+  MIXS LIB: NDAS FIL: E65LIB6.idx:E65LIB6.sdb
+\end{verbatim}
+
+\item[\dusa{ndepl}] number of isotopes in the depleting chain.
+
+\item[\dstr{descdepl}] input structure describing the
+depletion chain (see \Sect{descdepl}).
+
+\item[\dstr{descdeplA2}] simplified input structure describing the
+depletion chain in cases where an APOLIB-2 or APOLIB-XSM file is used (see \Sect{descdepl}).
+
+\item[\moc{CATL}] keyword to perform the following operations:
+\vspace{-0.15cm}
+\begin{itemize}
+\item create a new microlib or recover an existing \dds{microlib} in modification mode,
+\item catenate with a RHS \dds{microlib} in read-only mode,
+\item create the embedded  \dds{macrolib}.
+\end{itemize}
+
+\item[\moc{MAXS}] keyword to specify that the mixture density on \dusa{MICLIB}
+are to be modified. If \dusa{MICRHS} is present and \dstr{descmix2} is absent, a
+direct one to one correspondence between the isotope on both libraries is
+assumed. If \dusa{MICRHS} and \dstr{descmix2} are present, only the
+mixture on the library file specified by \dstr{descmix2} are updated using
+information from the \dusa{MICRHS}. If \dusa{MICRHS} is absent and
+\dstr{descmix2} is present, only the mixture on  \dusa{MICLIB} specified by
+\dstr{descmix2} are updated. This option is useful for implementing two-level
+computational schemes similar to REL-2005.
+
+\item[\moc{BURN}] keyword to specify that the mixture density on \dusa{MICLIB}
+are to be updated using information taken from \dusa{EVORHS}. If \dstr{descmix2}
+is absent, a direct one to one correspondence between the isotope on
+\dusa{EVORHS} and \dusa{MICLIB}  is assumed. If  \dstr{descmix2} is present, only
+the mixture specified by \dstr{descmix2} are updated using information from
+\dusa{EVORHS}. This option is useful for performing branching calculations.
+
+\item[\dusa{iburn}] burnup step from the burnup file to use. This step must be
+already present on the burnup file.
+
+\item[\dusa{tburn}] burnup time in days from the burnup file to use. This time
+step must be already present on the burnup file.
+
+\item[\dstr{descmix1}] input structure describing the
+isotopic and physical properties of a given mixture (see \Sect{descmix1}).
+
+\item[\dstr{descmix2}] input structure describing perturbations to the
+isotopic and physical properties of a given mixture (see \Sect{descmix2}).
+
+
+\end{ListeDeDescription}
+
+Note that it is possible to recompute the embedded macrolib in an existing microlib
+named {\tt MICRO} by writing
+\begin{verbatim}
+MICRO := LIB: MICRO :: MACR MIXS ;
+\end{verbatim}
+
+\subsubsection{Depletion data structure}\label{sect:descdepl}
+
+The structure \dstr{descdepl} describes the heredity of the radioactive decay
+and the neutron activation chain to be used in the isotopic depletion
+calculation.
+\begin{DataStructure}{Structure \dstr{descdepl}}
+\moc{CHAIN} \\
+$[[$ \dusa{NAMDPL} $[$ \dusa{izae} $]$ \\
+\hskip 1.0cm $[[~\{$ \moc{DECAY} \dusa{dcr} $|$ \\
+\hskip 2.0cm \dusa{reaction} $[$ \dusa{energy} $]~\}~]]$ \\
+\hskip 1.0cm $[~\{$ \moc{STABLE} $|$ \\
+\hskip 2.0cm \moc{FROM} $[[~\{$ \moc{DECAY} $|$ \dusa{reaction} $\}$
+$[[$ \dusa{yield} \dusa{NAMPAR} $]]~]]~\}~]~]]$\\
+\moc{ENDCHAIN}
+\end{DataStructure}
+
+\vspace{-0.15cm}
+
+\noindent
+with:
+
+\begin{ListeDeDescription}{mmmmmm}
+
+\item[\moc{CHAIN}] keyword to specify the beginning of the depletion chain.
+
+\item[\dusa{NAMDPL}] {\tt character*12} name of an isotope (or isomer) of the
+depletion chain that appears in the cross-section library.
+
+\item[\dusa{izae}] optional six digit integer representing the isotope. The first two
+digits represent the atomic number of the isotope; the next three indicate its
+mass number and the last digit indicates the  excitation level of the nucleus (0
+for a nucleus in its ground state, 1 for an isomer in its first exited state,
+etc.). For example, $^{238}$U in its ground state will be represented by
+\dusa{izae}=922380.
+
+\item[\moc{DECAY}] indicates that a decay reaction takes place either for
+production of this isotope or its depletion.
+
+\item[\dusa{dcr}] radioactive decay constant (in $10^{-8}$ s$^{-1}$) of the
+isotope. By default, \dusa{dcr}=0.0.
+
+\item[\dusa{reaction}] {\tt character*6} identification of a neutron-induced
+reaction that takes place either for production of this isotope, its depletion,
+or for producing energy. Example of reactions are following:
+
+\begin{ListeDeDescription}{mmmmmmmm}
+\item[\moc{NG}] indicates that a radiative capture reaction takes place either
+for production of this isotope, its depletion or for producing energy.
+
+\item[\moc{N2N}] indicates that the following reaction is taking place:
+$$ n +^{A}X_Z \to 2 n + ^{A-1}X_Z$$
+
+\item[\moc{N3N}] indicates that the following reaction is taking place:
+$$ n +^{A}X_Z \to 3 n + ^{A-2}X_Z$$
+
+\item[\moc{N4N}] indicates that the following reaction is taking place:
+$$ n +^{A}X_Z \to 4 n + ^{A-3}X_Z$$
+
+\item[\moc{NP}] indicates that the following reaction is taking place:
+$$ n +^{A}X_Z \to p + ^AY_{Z-1}$$
+
+\item[\moc{NA}] indicates that the following reaction is taking place:
+$$ n +^{A}X_Z \to ^4{\rm He}_2 + ^{A-3}X_{Z-2}$$
+
+\item[\moc{NFTOT}] indicates that a fission is taking place.
+\end{ListeDeDescription}
+
+\item[\dusa{energy}] energy (in MeV) recoverable per neutron-induced
+reaction of type \dusa{reaction}. If the energy associated to radiative capture
+is not explicitely given, it should be added to the energy released per fission.
+If {\tt H-FACTOR} information is available for isotope \dusa{NAMDPL}, \dusa{energy}
+contains only decay energy of lumped isotopes produced by \dusa{reaction} of \dusa{NAMDPL}.
+By default, \dusa{energy}=0.0 MeV.
+
+\item[\moc{STABLE}] non depleting isotope. Such an isotope may produces
+energy by neutron-induced reactions (such as radiative capture).
+
+\item[\moc{FROM}] indicates that this isotope is produced from decay or
+neutron-induced reactions.
+
+\item[\dusa{yield}] branching ratio or production yield expressed in fraction.
+
+\item[\dusa{NAMPAR}] {\tt character*12} name of the a parent isotope
+(or isomer) that appears in the cross-section library.
+
+\item[\moc{ENDCHAIN}] keyword to specify the end of the depletion chain.
+
+\end{ListeDeDescription}
+
+\vskip 0.15cm
+
+If the keyword \moc{APLIB2} or \moc{APXSM} was used in structure \dstr{desclib}, part of the
+depletion data is recovered from the APOLIB file: the fission yields, the
+radioactive decay constants and the energy released per fission or radiative
+capture. Moreover, the following simplified structure is used to provide the
+remaining depletion data:
+
+\begin{DataStructure}{Structure \dstr{descdeplA2}}
+\moc{CHAIN} \\
+$[[$ \dusa{NAMDPL} $[$ \moc{FROM} $[[$ $\{$ \moc{DECAY} $|$ \dusa{reaction} $\}$
+\dusa{yield} \dusa{NAMPAR} $]]$ $]$ $]]$\\
+\moc{ENDCHAIN}
+\end{DataStructure}
+
+\vskip 0.15cm
+
+In this case, the following rules apply:
+\begin{itemize}
+\item We should provide the names \dusa{NAMDPL} of {\sl all} the depleting
+isotopes (i.e. isotopes with a time-dependent number density), including the
+pseudo fission products (PFP).
+\item The fission father reactions (\moc{NFTOT}) are not given.
+\item The stable isotopes are automatically recovered from the
+APOLIB file. They are not given in structure \dstr{descdeplA2}.
+\item An isotope is considered to be stable if it is not present in
+structure \dstr{descdeplA2}, has no father and no daughter,
+but can release energy by fission or radiative capture.
+\item It is possible to truncate the isotope name \dusa{NAMDPL} at the
+underscore. For example, {\tt D2O\_3\_P5} can be simply written {\tt D2O}.
+\item Only the radioactive decay constants of the isotopes present in
+structure \dstr{descdeplA2} are recovered from the APOLIB file. The
+radioactive decay constants of the other isotopes are set to zero.
+\end{itemize}
+
+\subsubsection{Mixture description structure}\label{sect:descmix1}
+
+The structure \dstr{descmix1} is used to describe the isotopic composition and
+the physical properties, such as the temperature and density, of a mixture.
+
+\begin{DataStructure}{Structure \dstr{descmix1}}
+\moc{MIX} $[$ \dusa{matnum} $]$ $\{$ \\
+\hskip 1.0cm $[$\dusa{temp} $[$ \dusa{denmix} $]~]~~[~\{$ \moc{NOEV} $|$ \moc{EVOL} $\}~]~~[~\{$ \moc{NOGAS}
+    $|$ \moc{GAS}$\}~]$\\
+\hskip 2.0cm $[[~[$ \dusa{NAMALI} \moc{=} $]$ \dusa{NAMISO} \dusa{dens} $[~\{$ \dusa{dil} 
+    $|$ \moc{INF} $\}~]$\\
+\hskip 2.0cm $[~[$ \moc{CORR} $]$ \dusa{inrs} $]~[$ \moc{DBYE} \dusa{tempd} $]~[$ \moc{SHIB} \dusa{NAMS} $]$ \\
+\hskip 2.0cm $[$ \moc{THER} \dusa{ntfg} \dusa{HINC} $[$ \moc{TCOH} \dusa{HCOH} $]~[$ \moc{RESK} $]~]$ \\
+\hskip 2.0cm $[$ \moc{IRSET} $\{$ \dusa{gir} $|~\{$ \moc{PT} $|$ \moc{PTMC} $|$ \moc{PTSL} $|$ \moc{RSE} $\}~\}~\{$
+\dusa{nir} $|$ \moc{NONE} $\}~]~~[~\{$ \moc{NOEV} $|$ \moc{EVOL} $|$ \moc{SAT} $\}~]~]]$ \\
+\hskip 1.0cm $|$ \\
+\hskip 1.0cm \moc{COMB} $[[$ \dusa{mati} \dusa{relvol} $]]~\}$
+\end{DataStructure}
+
+\vspace{-0.15cm}
+
+\noindent
+where:
+
+\begin{ListeDeDescription}{mmmmmm}
+
+\item[\moc{MIX}] keyword to specify the number identifying the next mixture to
+be read.
+
+\item[\dusa{matnum}] mixture identifier. The maximum value that \dusa{matnum}
+may have is \dusa{nmixt}. When \dusa{matnum} is absent, the mixtures are
+numbered successively starting from 1 if no mixture has yet been specified or
+from the last mixture number specified + 1.
+
+\item[\dusa{temp}] absolute temperature (in Kelvin) of the isotopic mixture.
+It is optional only when this mixture is to be updated, in which case the old
+temperature associated with the mixture is used.
+
+\item[\dusa{denmix}] mixture density in $g \ cm^{-3}$. 
+
+\item[\dusa{NAMALI}] {\tt character*8} alias name for an isotope to be used
+locally. When the alias name is absent, the isotope name used locally is
+identical to the first 8-character isotope name on the library.
+
+\item[\moc{=}] keyword to specify to which isotope in a library is associated
+the previous alias name.
+
+\item[\dusa{NAMISO}] {\tt character*12} name of an isotope present in the
+library which is included in this mixture.
+
+\item[\dusa{dens}]  isotopic concentration of the isotope \dusa{NAMISO} in the
+current mixture in $10^{24}cm^{-3}$.  When the mixture density  \dusa{denmix}
+is specified, the relative weight percentage of each of the isotopes in this
+mixture is to be provided.
+
+\item[\dusa{dil}] group independent microscopic dilution cross section (in
+barns) of the isotope \dusa{NAMISO} in this mixture. It is possible to
+recalculate a group dependent dilution for an isotope by the use of the
+\moc{SHI:} or \moc{TONE:} operator (see \Sect{SHIData} and \Sect{TONEData}). In this case, the dilution is only used
+as a starting point for the self-shielding iterations and has no effect on the
+final result. If the dilution is not given or is larger than $10^{10}$ barns,
+an infinite dilution is assumed.
+
+\item[\moc{INF}] keyword to specify that a dilution of $10^{10}$ barns is to
+be associated with this isotope. This value represents an infinite dilution (the
+isotope is present in trace amounts only). It is possible to
+recalculate a group dependent dilution for an isotope by the use of the
+\moc{SHI:} operator (see \Sect{SHIData}) or \moc{TONE:} operator (see \Sect{TONEData}). In this case, the dilution is only used
+as a starting point for the self-shielding iterations and has no effect on the
+final result. If the dilution is not given an infinite dilution is assumed.
+
+\item[\moc{CORR}] keyword to specify that the resonances of an isotope are correlated
+with those of other isotopes with the same \dusa{inrs} index. This option is only
+available with the {\sl Ribon extended} model\cite{nse2004} or wth the {\sl subgroup
+projection method} (SPM)\cite{SPM09}  in energy groups where
+this model is set. If this option is selected for
+an isotope, it must be set for all isotopes with the same \dusa{inrs} index. By default,
+the resonances of distinct isotopes are assumed to be uncorrelated.
+
+\item[\dusa{inrs}] index of the resonant region associated with this isotope.
+By default \dusa{inrs}=0 and the isotope is not a candidate for self-shielding.
+When \dusa{inrs}$\ne$0, the isotope can be self-shielded where it is assumed that a given
+isotope distributed with different concentrations in a number of mixtures and
+having the same value of \dusa{inrs} will share the same fine flux. 
+Should we wish to self-shield both the clad and the fuel it is important
+to assign a different \dusa{inrs} number
+to each. If a single type of fuel is located in different mixture in
+{\sl onion-peel fashion}, it is necessary to attribute a single \dusa{inrs} value
+to this fuel.
+
+\item[\moc{DBYE}] keyword to specify that the absolute temperature of the
+isotope is different from that of the isotopic mixture. This option is useful to
+define Debye-corrected temperature.
+
+\item[\dusa{tempd}] absolute temperature (in Kelvin) of the isotope. By
+default \dusa{tempd}=\dusa{temp}.
+
+\item[\moc{SHIB}] keyword to specify that the name of the isotope containing
+the information related to the self-shielding is different from the initial name
+of the isotope. This option is not required if a MATXS or a {\sc draglib} file is used.
+
+\item[\dusa{NAMS}] {\tt character*12} name of a record in the library
+containing the self-shielding data. This name is required if the dilution is
+not infinite or a non zero resonant region is associated with this isotope and \dusa{NAMS}
+is different from \dusa{NAMISO}. This record must be contained in the same
+library file as record \dusa{NAMISO}.
+
+\item[\moc{THER}] keyword to specify that the thermalization and resonant elastic
+scattering kernel effects are to be included with the cross sections when using a
+\moc{MATXS} or \moc{MATXS2} format library.
+
+\item[\dusa{HINC}] {\tt character*6} name  of the incoherent thermalization
+effects which will be taken into account. The incoherent effects are those that
+may be described by the $S(\alpha,\beta)$ scattering law. The value \moc{FREE}
+is used to simulate the effects of a gas.
+
+\item[\moc{TCOH}]  keyword to specify that coherent thermalization effects
+will be taken into account.
+
+\item[\dusa{HCOH}] {\tt character*6} name of the coherent thermalization
+effects which will be taken into account. The coherent effects are the
+{\sl vectorial reactions} in the \moc{MATXS} or \moc{MATXS2} format library where
+the name is terminated by the `\$' suffix. They are generally available for
+graphite, beryllium, beryllium oxide, polyethylene and zirconium hydroxide.
+
+\item[\moc{RESK}]  keyword to specify that resonant elastic scattering kernel effects
+will be taken into account.
+
+\item[\dusa{ntfg}]  number of energy groups that will be affected by the
+thermalization and resonant elastic scattering kernel effects.
+
+\item[\moc{IRSET}] keyword to specify an intermediate resonance (IR)
+approximation or the {\sl Ribon extended} model for some energy groups. By default, an
+IR approximation with the value of the Goldstein-Cohen parameter found on the library
+is used. If no value is found on the library, a statistical (ST) model\cite{st} is set in
+all groups by default. The ``{\tt IRSET PT 1}'' option is set by default if keyword \moc{PT}
+is selected in structure \dstr{desclib}. The same rule applies for \moc{PTMC}, \moc{PTSL} or
+\moc{RSE}.
+
+\item[\dusa{gir}]  imposed Goldstein-Cohen IR parameter. A Goldstein-Cohen IR parameter
+$0 \le \lambda_g\le 1$ is set in energy group $g$. A value of 1.0 stands for
+a statistical (ST) approximation. A value of 0.0 stands for an infinite mass
+(IM or WR) approximation.
+
+\item[\moc{PT}] keyword to enable the calculation of CALENDF--type probability tables in some energy groups. The
+slowing-down correlated weight matrices are {\sl not} computed. This type of probability tables is consistent
+with the Sanchez-Coste self-shielding method and with the subgroup projection method (SPM).\cite{SPM09}
+
+\item[\moc{PTMC}] keyword to enable the calculation of CALENDF--type probability tables, similar to the \moc{PT}
+procedure. Here, the base points of the probability tables corresponding
+to fission and scattering cross sections and to components of the transfer scattering matrix are also obtained using the CALENDF approach.
+
+\item[\moc{PTSL}] keyword to enable the calculation of CALENDF--type probability tables, consistent
+with the Ribon extended model, in some energy groups.
+
+\item[\moc{RSE}] keyword to enable the calculation of RSE--type probability tables in some energy groups.
+
+\item[\dusa{nir}]  the intermediate resonance (IR) approximation or the Ribon extended
+model is imposed for energy groups with an index equal or greater than \dusa{nir}.
+A statistical (ST) model is set in other groups.
+
+\item[\moc{NONE}] keyword to specify that a statistical (ST) model is set in
+all groups.
+
+\item[\moc{NOEV}] keyword to force a mixture or a nuclide to be non-depleting (even in
+cases where it is potentially depleting). Note that the mixture or nuclide keeps its
+capability to produce energy. By default, the depleting isotopes are
+automatically regognized as depleting.
+
+\item[\moc{EVOL}] keyword to force a mixture or a nuclide to be depleting. By default, only fission products and
+fissile isotopes are depleting.
+
+\item[\moc{NOGAS}] keyword to specify that a mixture has a solid or liquid state (used for stopping power correction).
+This is the default option.
+
+\item[\moc{GAS}] keyword to specify that a mixture has a gaseous state (used for stopping power correction).
+
+\item[\moc{SAT}] keyword to force a nuclide to be at saturation. By default, the saturation approximation is
+automatically set as a function of the half life and capture cross sections of the isotope.
+
+\item[\moc{COMB}]  keyword to specify that this mixture is reset with a
+combination of previously defined mixtures.
+
+\item[\dusa{mati}]  number associated with a previously defined mixture. In
+order to insert some void in a mixture use \dusa{mati}=0. If the mixture is not
+already defined one assumes that it represents a voided mixture.
+
+\item[\dusa{relvol}] relative volume $V_{i}$ occupied by mixture
+\dusa{mati}=$i$ in \dusa{matnum}.  Two cases can be considered, namely that
+where the density $\rho_{i}$ of each mixture \dusa{mati} is provided along with
+the weight percent for each isotope $J$ ($W_{i}^{j}$) and the case where the
+explicit concentration $N_{i}^{j}$ of each isotope in a \dusa{mati} was provided
+(it is forbidden to combined two mixtures with different isotopic content
+description). In the case where the initial mixtures are defined using densities
+$\rho_{i}$, the density ($\rho_k$) and volume ($V_{k}$) of the final mixture
+will become:
+  $$V_{k}=\sum_{i} V_{i} $$
+  $$\rho_{k}=\frac{1}{V_{k}} \sum_{i}\rho_{i}V_{i}$$
+and the weight percent will be changed in a consistent way, namely
+  $$W_{k,J}=\frac{\rho_{i}V_{i}W_{i,J}}{\rho_{k} V_{k} } $$
+When the explicit concentration are given we will use:
+  $$N_{k,J}=\frac{V_{i}N_{i,J}}{V_{k} } $$
+
+\vskip 0.08cm
+
+There is a very common usage of keyword \moc{COMB}. In the following example, a new mixture with index 42
+is defined in such a way to be identical to an existing mixture with index 25. 
+\begin{verbatim}
+    MIX 42 COMB 25 1.0
+\end{verbatim}
+
+\end{ListeDeDescription}
+
+Note that in the structure \dstr{descmix1} one only needs to describe the
+isotopes initially present in each mixture. DRAGON will then automatically
+associate with each depleting mixture the additional isotopes required by the
+available burnup chain. Moreover, the microscopic cross-section library
+associated with these new isotopes will be the same as that of their parent
+isotope. For example, suppose that mixture 1 contains isotope {\tt U235} which
+is to be read on the DRAGON-formatted library associated with file {\tt
+DRAGLIB}. Assume also that the depletion chain, which is written on the 
+WIMS--AECL format library associated with file {\tt WIMSLIB}, states that isotope
+{\tt U236} (initially absent in the mixture) can be generated form {\tt U235} by
+neutron capture. Then, one can either specify explicitly from which library file
+the microscopic cross sections associated with isotope {\tt U236} (zero
+concentration) are to be read, or omit {\tt U236} from the mixture description
+in which case DRAGON will assume that the microscopic cross sections associated
+with isotope {\tt U236} are to be read from the same library as the cross
+section for isotope {\tt U235}. Note that the isotopes added automatically will
+remain at infinite dilution.
+
+\vskip 0.15cm
+
+If the \moc{SHI:} or \moc{TONE:} module is used for performing self-shielding calculation,
+the self-shielding data for an isotope takes the form
+\begin{verbatim}
+    U235     = U235  5.105E-5 1
+\end{verbatim}
+\noindent where the last index indicates the self-shielding region (1 in this case). 
+
+\vskip 0.15cm
+
+If the {\tt USS:} module implementing the subgroup method is used,
+additional self-shielding data is required:
+\begin{itemize}
+\item Physical probability tables are used (keyword {\tt SUBG}). Consider the following data:
+\begin{verbatim}
+    U235     = U235  5.105E-5 1 IRSET 0.0 81
+\end{verbatim}
+The data ``{\tt IRSET 0.0 81}'' indicates that a Goldstein-Cohen parameter
+$\lambda_g$ equal
+to 0.0 is used for all energy groups with an index equal or greater than 81. A value
+of $\lambda_g=1.0$ corresponding to a statistical model is used by default.
+
+\item Mathematical probability tables (with slowing-down correlated weight matrices) are used (keyword {\tt PTSL})
+{\sl or} mathematical probability tables with the subgroup projection method (SPM)\cite{SPM09} are used (keyword {\tt PT}
+or {\tt PTMC}). Consider the following data:
+\begin{verbatim}
+    U235     = U235  5.105E-5 1 IRSET PT 5
+\end{verbatim}
+The Goldstein-Cohen approximation is not used with mathematical (CALENDF) probability tables. The data ``{\tt IRSET PT 5}''
+indicates that the CALENDF probability tables are used for energy groups with an index equal
+or greater than 5, {\sl with the exception of the energy groups where no Autolib data
+is available} and a statistical model (with physical probability tables) is used for energy groups with an index smaller
+than 5. A statistical model is also imposed in groups where no Autolib data is available.
+
+\vskip 0.15cm
+
+The following data:
+\begin{verbatim}
+    U235     = U235  5.105E-5 1 IRSET PT NONE
+\end{verbatim}
+\noindent is useful to impose the statistical model (with physical probability tables) in all energy groups. This is equivalent of selecting
+the {\tt SUBG} keyword in structure \dstr{desclib}.
+
+\vskip 0.15cm
+
+Mathematical (CALENDF) probability tables are used in each energy group where Autolib data is available if the following data is set:
+\begin{verbatim}
+    U235     = U235  5.105E-5 1 IRSET PT 1
+\end{verbatim}
+\noindent {\sl This latter definition is equivalent to the default behavior obtained using}
+\begin{verbatim}
+    U235     = U235  5.105E-5 1
+\end{verbatim}
+\end{itemize}
+
+\vskip 0.25cm
+\goodbreak
+
+\subsubsection{Mixture modification description structure}\label{sect:descmix2}
+
+The structure \dstr{descmix2} is used to describe the modifications in the isotopic composition of a mixture.
+
+\begin{DataStructure}{Structure \dstr{descmix2}}
+$\{$ \moc{MIX}  \dusa{matnum} $[$ \dusa{matold} $]$ $[$ \dusa{relden} $]$
+$[$ \dusa{NAMALI} \dusa{dens} $]~[~\{$ \moc{NOEV} $|$ \moc{EVOL} $\}~]~|$ \moc{ALL} $\}$
+\end{DataStructure}
+
+\vspace{-0.15cm}
+
+\noindent
+where:
+
+\begin{ListeDeDescription}{mmmmmm}
+
+\item[\moc{MIX}] keyword to specify the number identifying the next mixture to
+be updated.
+
+\item[\dusa{matnum}] mixture identifier on \dusa{MICLIB}. 
+
+\item[\dusa{matold}] mixture identifier on \dusa{MICRHS}. By default, \dusa{matold}$=$\dusa{matnum}.
+
+\item[\dusa{relden}] relative density of updated mixture. The  concentration
+of each isotope in the mixture is to be multiplied by this factor whether it 
+comes from \dusa{MICLIB}, from \dusa{MICRHS} or is
+specified explicitly using \dusa{dens}. 
+
+\item[\dusa{NAMALI}] {\tt character*8} alias name for an isotope on
+\dusa{MICLIB} to be modified. 
+
+\item[\dusa{dens}] isotopic concentration of the isotope \dusa{NAMISO} in the
+current mixture in $10^{24}cm^{-3}$.  When \dusa{relden} is specified, the
+isotopic concentration becomes \dusa{dens}$\times$\dusa{relden}.
+
+\item[\moc{NOEV}] keyword to force a mixture to be non-depleting (even in
+cases where it is potentially depleting). Note that the mixture keeps its
+capability to produce energy.
+
+\item[\moc{EVOL}] keyword to force a mixture to be depleting. By default, only
+mixtures containing fission products and/or fissile isotopes are depleting.
+
+\item[\moc{ALL}] keyword to copy all isotopes from \dusa{MICRHS} into \dusa{MICLIB}. Isotopes in \dusa{MICRHS}
+must be assigned to mixture indices not existing in \dusa{MICLIB}.
+
+\end{ListeDeDescription}
+
+\vskip 0.2cm
+
+\subsubsection{Cross sections in Dragon}\label{sect:xs}
+Multigroup cross sections in Draglibs files are of two types:
+\begin{itemize}
+\item Vectorial cross sections $\sigma_{x,g}$
+\item Matrix cross sections $\sigma_{x,g\leftarrow h}.$
+\end{itemize}
+\begin{enumerate}
+\item Total cross sections $\sigma_g$ are provided in ENDF evaluations as {\tt MT} $=1$. They are redundent with other information in the same evaluation. The vectorial total cross section is defined as
+\begin{eqnarray}
+\nonumber \sigma_g\negthinspace &=&\negthinspace \sigma_{{\rm e},g}+\sigma_{{\rm in},g}+\sigma_{{\rm (n,2n)},g}+\sigma_{{\rm (n,3n)},g}+\sigma_{{\rm (n,4n)},g}+\sigma_{{\rm f},g}+\sigma_{{\rm p},g}+\sigma_{\gamma,g}
++\sigma_{{\rm d},g}+\sigma_{{\rm t},g}+\sigma_{\alpha,g}\\
+&+&\negthinspace \sigma_{2\alpha,g}+\sigma_{{\rm (n,np)},g}+\sigma_{{\rm any},g}
+\end{eqnarray}
+\noindent where $\sigma_{{\rm e},g}$ and $\sigma_{{\rm in},g}$ are the elastic and inelastic scattering cross sections and where the matrix cross sections are transformed into vectorial cross sections using
+\begin{equation}
+\sigma_{x,g}=\sum_h \sigma_{x,h\leftarrow g} \ , \ \ {\rm except \ for \ (n,}x{\rm n) \ reactions.}
+\end{equation}
+\item Inelastic scattering cross sections are sum over {\tt MT} 51 to 91 in the ENDF evaluation:
+\begin{equation}
+\sigma_{{\rm in},g}=\sum_{{\sl mt}=51}^{91} \sigma_{{\sl mt},g}=\sum_{{\sl mt}=51}^{91} \sum_h \sigma_{{\sl mt},h\leftarrow g} .
+\end{equation}
+\item (n,$x$n) vectorial cross sections are divided by the secondary neutron multiplicity:
+\begin{equation}
+\sigma_{{\rm (n,2n)},g}={1\over 2}\sum_h \sigma_{{\rm (n,2n)},h\leftarrow g} \ , \ \ \sigma_{{\rm (n,3n)},g}={1\over 3}\sum_h \sigma_{{\rm (n,3n)},h\leftarrow g} \ , \ \ \sigma_{{\rm (n,4n)},g}={1\over 4}\sum_h \sigma_{{\rm (n,4n)},h\leftarrow g} .
+\end{equation}
+\item {\tt SCAT} matrix reactions in Dragon are defined as
+\begin{eqnarray}
+\nonumber \sigma_{{\tt scat},h\leftarrow g} \negthinspace\negthinspace &=& \negthinspace\negthinspace \sigma_{{\rm e},h\leftarrow g}+\sigma_{{\rm (n,2n)},h\leftarrow g}+\sigma_{{\rm (n,3n)},h\leftarrow g}+\sigma_{{\rm (n,4n)},h\leftarrow g}
++\sum_{{\sl mt}=51}^{91} \sigma_{{\sl mt},h\leftarrow g} \\
+&+& \negthinspace\negthinspace \sigma_{{\rm any},h\leftarrow g} \, .
+\end{eqnarray}
+\item Vectorial {\sl neutronic scattering} ({\tt SIGS}) in Dragon is defined as
+\begin{equation}
+\sigma_{{\tt sigs},g}=\sum_h \sigma_{{\tt scat},h\leftarrow g}
+\end{equation}
+\noindent so that the {\sl neutronic absorption}, used to compute the $K_\infty$ is
+\begin{eqnarray}
+\nonumber \sigma_g-\sigma_{{\tt sigs},g}\negthinspace &=&\negthinspace \sigma_{{\rm f},g}+\sigma_{{\rm p},g}+\sigma_{\gamma,g}
++\sigma_{{\rm d},g}+\sigma_{{\rm t},g}+\sigma_{\alpha,g}+\sigma_{2\alpha,g}+\sigma_{{\rm (n,np)},g}\\
+&-&\negthinspace \sigma_{{\rm (n,2n)},g}-2\sigma_{{\rm (n,3n)},g}-3\sigma_{{\rm (n,4n)},g}
+\label{eq:eq1}
+\end{eqnarray}
+\noindent where all these terms are available in the Dragon microlib under the following names:\\
+\vskip 0.1cm
+\begin{tabular}{| l | l | l |}
+\hline
+Dragon name & $\sigma_x$ & type \\
+\hline
+{\tt NTOT0} & $\sigma_g$ & total \\
+{\tt SIGS00} & $\sigma_{{\tt sigs},g}$ & neutronic scattering \\
+{\tt NFTOT} &$\sigma_{{\rm f},g}$ & fission \\
+{\tt NP} & $\sigma_{{\rm p},g}$ & (n,p) \\
+{\tt NG} & $\sigma_{\gamma,g}$ & (n,$\gamma$) \\
+{\tt ND} &$\sigma_{{\rm d},g}$ & (n,d) \\
+{\tt NT} &$\sigma_{{\rm t},g}$ & (n,t) \\
+{\tt NA} &$\sigma_{\alpha,g}$ & (n,$\alpha$) \\
+{\tt N2A} &$\sigma_{2\alpha,g}$ & (n,2$\alpha$) \\
+{\tt NNP} &$\sigma_{{\rm (n,np)},g}$ & (n,np) \\
+{\tt NX} &$\sigma_{{\rm any},g}$ & (n,anything) \\
+{\tt N2N} &$\sigma_{{\rm (n,2n)},g}$ & (n,2n) \\
+{\tt N3N} &$\sigma_{{\rm (n,3n)},g}$ & (n,3n) \\
+{\tt N4N} &$\sigma_{{\rm (n,4n)},g}$ & (n,4n) \\
+\hline
+\end{tabular}
+\item The {\sl infinite multiplication factor} $K_\infty$ in a Dragon mixture is defined as
+\begin{equation}
+K_\infty={\sum\limits_g \nu\Sigma_{{\rm f},g}\bar\phi_g \over \sum\limits_g \left(\Sigma_g-\Sigma_{{\tt sigs},g}\right)\bar\phi_g}
+\end{equation}
+\noindent where $\nu\Sigma_{{\rm f},g} $, $\Sigma_g$ and $\Sigma_{{\tt sigs},g}$ are the macroscopic $\nu$-fission, total and
+neutronic scattering cross sections, and $\bar\phi_g$ is the neutron flux.
+
+\end{enumerate}
+
+\eject
-- 
cgit v1.2.3

