=======================================================================VIRGIN  
                                                                        VIRGIN  
      PROGRAM VIRGIN                                                    VIRGIN  
      VERSION 76-1 (NOVEMBER 1976)                                      VIRGIN  
      VERSION 84-1 (JUNE 1984)   *DOUBLE PRECISION ENERGY               VIRGIN  
      VERSION 86-1 (JANUARY 1986)*FORTRAN-77/H VERSION                  VIRGIN  
      VERSION 88-1 (JULY 1988)   *OPTION...INTERNALLY DEFINE ALL I/O    VIRGIN  
                                  FILE NAMES (SEE, SUBROUTINE FILEIO    VIRGIN  
                                  FOR DETAILS).                         VIRGIN  
                                 *IMPROVED BASED ON USER COMMENTS.      VIRGIN  
      VERSION 89-1 (JANUARY 1989)*PSYCHOANALYZED BY PROGRAM FREUD TO    VIRGIN  
                                  INSURE PROGRAM WILL NOT DO ANYTHING   VIRGIN  
                                  CRAZY.                                VIRGIN  
                                 *UPDATED TO USE NEW PROGRAM CONVERT    VIRGIN  
                                  KEYWORDS.                             VIRGIN  
                                 *ADDED LIVERMORE CIVIC COMPILER        VIRGIN  
                                  CONVENTIONS.                          VIRGIN  
      VERSION 92-1 (JANUARY 1992)*COMPLETE RE-WRITE                     VIRGIN  
                                 *OUTPUT IN PLOTTAB FORMAT              VIRGIN  
                                 *UP TO 2000 THICKNESSES                VIRGIN  
                                 *INCREASED INCORE PAGE SIZE TO 6000    VIRGIN  
                                  CROSS SECTION POINTS                  VIRGIN  
                                 *ADDED PHOTON CALCULATIONS             VIRGIN  
                                 *ADDED BLACKBODY SPECTRUM              VIRGIN  
                                 *ADDED MULTIPLE LAYERS                 VIRGIN  
                                 *ADDED SPATIALLY DEPENDENT DENSITY     VIRGIN  
                                 *ADDED FORTRAN SAVE OPTION             VIRGIN  
                                 *COMPLETELY CONSISTENT I/O ROUTINES -  VIRGIN  
                                  TO MINIMIZE COMPUTER DEPENDENCE.      VIRGIN  
      VERSION 92-2 (MAY 1992)    *CORRECTED TO HANDLE MULTIGROUP CROSS  VIRGIN  
                                  SECTIONS AS INPUT IN ENDF/B FORMAT.   VIRGIN  
      VERSION 96-1 (JANUARY 1996) *COMPLETE RE-WRITE                    VIRGIN  
                                  *IMPROVED COMPUTER INDEPENDENCE       VIRGIN  
                                  *ALL DOUBLE PRECISION                 VIRGIN  
                                  *ON SCREEN OUTPUT                     VIRGIN  
                                  *UNIFORM TREATMENT OF ENDF/B I/O      VIRGIN  
                                  *IMPROVED OUTPUT PRECISION            VIRGIN  
                                  *DEFINED SCRATCH FILE NAMES           VIRGIN  
      VERSION 99-1 (MARCH 1999)   *CORRECTED CHARACTER TO FLOATING      VIRGIN  
                                   POINT READ FOR MORE DIGITS           VIRGIN  
                                  *UPDATED TEST FOR ENDF/B FORMAT       VIRGIN  
                                   VERSION BASED ON RECENT FORMAT CHANGEVIRGIN  
                                  *GENERAL IMPROVEMENTS BASED ON        VIRGIN  
                                   USER FEEDBACK                        VIRGIN  
      VERS. 2000-1 (FEBRUARY 2000)*GENERAL IMPROVEMENTS BASED ON        VIRGIN  
                                   USER FEEDBACK                        VIRGIN  
      VERS. 2002-1 (MAY 2002)     *OPTIONAL INPUT PARAMETERS            VIRGIN  
      VERS. 2004-1 (MARCH 2004)   *ADDED INCLUDE FOR COMMON             VIRGIN  
                                  *UP TO 2000 THICKNESSES               VIRGIN  
                                  *INCREASED INCORE PAGE SIZE TO 60,000 VIRGIN  
      VERS. 2007-1 (JAN.  2007)   *CHECKED AGAINST ALL ENDF/B-VII.      VIRGIN  
                                  *INCREASED INCORE PAGE SIZE TO        VIRGIN  
                                   240,000 FROM 60,000.                 VIRGIN  
      VERS. 2007-2 (DEC.  2007)   *72 CHARACTER FILE NAME.              VIRGIN  
      VERS. 2010-1 (Apr.  2010)   *General update based on user feedbackVIRGIN  
                                  *INCREASED INCORE PAGE SIZE TO        VIRGIN  
                                   600,000 FROM 240,000.                VIRGIN  
      VERS. 2012-1 (Aug.  2012)   *Added CODENAME                       VIRGIN  
                                  *32 and 64 bit Compatible             VIRGIN  
                                  *Added ERROR stop                     VIRGIN  
      VERS. 2015-1 (Jan.  2015)   *Extended OUT9.                       VIRGIN  
                                  *Replaced ALL 3 way IF Statements.    VIRGIN  
                                  *Generalized TART Group Structures.   VIRGIN  
                                  *Generalized SAND-II Group Structures.VIRGIN  
                                  *Extended SAND-II to 60, 150, 200 MeV.VIRGIN  
      VERS. 2015-2 (Apr.  2015)   *Changed ALL data to "D" instead of   VIRGIN  
                                   "E" to insure it is REAL*8 and avoid VIRGIN  
                                   Truncation ERRORS.                   VIRGIN  
      VERS. 2017-1 (May   2017)   *Added UKAEA 1102 Group Structure.    VIRGIN  
                                  *Increased points to 3,000,000        VIRGIN  
                                  *Increased groupd to 30,000           VIRGIN  
                                  *Updated based on user feedback       VIRGIN  
                                  *Defintion of built-in group structureVIRGIN  
                                   using SUBROUTINE GROPE is identical  VIRGIN  
                                   for GROUPIE and VIRGIN.              VIRGIN  
                                  *All floating point parameters changedVIRGIN  
                                   to character inout + IN9 conversion. VIRGIN  
      VERS. 2018-1 (Jan.  2018)   *Decreased PAGE size from 3,000,000   VIRGIN  
                                   to 1,500,000                         VIRGIN  
                                  *On-line output for ALL ENDERROR      VIRGIN  
      VERS. 2019-1 (June  2019)   *Additional Interpolation Law Tests   VIRGIN  
                                  *Checked Maximum Tabulated Energy to  VIRGIN  
                                   insure it is the same for all MTs -  VIRGIN  
                                   if not, print WARNING messages.      VIRGIN  
      VERS. 2020-1 (Feb.  2020)   *Identical to 2019-1.                 VIRGIN  
                                                                        VIRGIN  
      2015-2 Acknowledgment                                             VIRGIN  
      =====================                                             VIRGIN  
      I thank Andrej Trkov (NDS, IAEA) for finding the problem with     VIRGIN  
      the "E" formatted DATA (this effected both VIRGIN and GROUPIE).   VIRGIN  
      I also thank Andrej for overseeing the entire PREPRO project      VIRGIN  
      at IAEA, Vienna; he is part of a truly International team who     VIRGIN  
      worked together to produce PREPRO-2015-2, and to make it          VIRGIN  
      available Internationally on-line for FREE to ALL users.          VIRGIN  
                                                                        VIRGIN  
      OWNED, MAINTAINED AND DISTRIBUTED BY                              VIRGIN  
      ------------------------------------                              VIRGIN  
      THE NUCLEAR DATA SECTION                                          VIRGIN  
      INTERNATIONAL ATOMIC ENERGY AGENCY                                VIRGIN  
      P.O. BOX 100                                                      VIRGIN  
      A-1400, VIENNA, AUSTRIA                                           VIRGIN  
      EUROPE                                                            VIRGIN  
                                                                        VIRGIN  
      ORIGINALLY WRITTEN BY                                             VIRGIN  
      ------------------------------------                              VIRGIN  
      Dermott E. Cullen                                                 VIRGIN  
                                                                        VIRGIN  
      PRESENT CONTACT INFORMATION                                       VIRGIN  
      ---------------------------                                       VIRGIN  
      Dermott E. Cullen                                                 VIRGIN  
      1466 Hudson Way                                                   VIRGIN  
      Livermore, CA 94550                                               VIRGIN  
      U.S.A.                                                            VIRGIN  
      Telephone  925-443-1911                                           VIRGIN  
      E. Mail    RedCullen1@Comcast.net                                 VIRGIN  
      Website    RedCullen1.net/HOMEPAGE.NEW                            VIRGIN  
                                                                        VIRGIN  
      PURPOSE                                                           VIRGIN  
      -------                                                           VIRGIN  
      THIS PROGRAM IS DESIGNED TO CALCULATE UNCOLLIDED (I.E. VIRGIN)    VIRGIN  
      FLUX AND REACTIONS DUE TO TRANSMISSION OF A MONODIRECTIONAL       VIRGIN  
      BEAM OF NEUTRONS THROUGH ANY THICKNESS OF MATERIAL. IN ORDER      VIRGIN  
      TO SIMULATE AN EXPERIMENTAL MEASUREMENT THE RESULTS ARE GIVEN     VIRGIN  
      AS INTEGRALS OVER ENERGY TALLY GROUPS (AS OPPOSED TO POINTWISE    VIRGIN  
      IN ENERGY). BY TAKING THE RATIO OF REACTIONS TO FLUX IN EACH      VIRGIN  
      GROUP AN EQUIVALENT SPATIALLY DEPENDENT GROUP AVERAGED CROSS      VIRGIN  
      SECTION IS CALCULATED BY THE PROGRAM.                             VIRGIN  
                                                                        VIRGIN  
      EVALUATED DATA                                                    VIRGIN  
      --------------                                                    VIRGIN  
      THE EVALUATED DATA MUST BE IN THE ENDF/B FORMAT. HOWEVER IT       VIRGIN  
      MUST BE LINEAR-LINEAR INTERPOLABLE IN ENERGY-CROSS SECTION        VIRGIN  
      BETWEEN TABULATED POINTS. SINCE ONLY CROSS SECTIONS (FILE 3 OR 23)VIRGIN  
      ARE USED, THIS PROGRAM WILL WORK ON ANY VERSION OF ENDF/B         VIRGIN  
      (I.E. ENDF/B-I, II, III, IV, V OR VI).                            VIRGIN  
                                                                        VIRGIN  
      RELATED COMPUTER CODES                                            VIRGIN  
      ----------------------                                            VIRGIN  
      IN ORDER TO CONVERT ENDF/B DATA TO THE FORM REQUIRED BY THIS CODE VIRGIN  
      THE FOLLOWING COMPUTER CODES MAY BE USED,                         VIRGIN  
                                                                        VIRGIN  
      LINEAR  - CONVERT FROM GENERAL ENDF/B INTERPOLATION TO LINEAR-    VIRGIN  
                LINEAR INTERPOLATION.                                   VIRGIN  
      RECENT  - ADD THE RESONANCE CONTRIBUTION TO TABULATED BACKGROUND  VIRGIN  
                CROSS SECTIONS TO OBTAIN LINEAR-LINEAR INTERPOLABLE     VIRGIN  
                RESULTS.                                                VIRGIN  
      SIGMA1  - DOPPLER BROADEN CROSS SECTION TO OBTAIN LINEAR-LINEAR   VIRGIN  
                INTERPOLABLE RESULTS.                                   VIRGIN  
      MIXER   - MIX INDIVIDUAL MATERIALS TOGETHER TO DEFINE COMPOSITE   VIRGIN  
                MIXTURES, E.G., COMBINE MATERIALS TO DEFINE STAINLESS   VIRGIN  
                STELL.                                                  VIRGIN  
                                                                        VIRGIN  
      IN ORDER TO PLOT THE OUTPUT RESULTS OF THIS CODE USE PROGRAM      VIRGIN  
      PLOTTAB.                                                          VIRGIN  
                                                                        VIRGIN  
      COPIES OF ANY OR ALL OF THESE CODES MAY BE OBTAINED FROM D.E.     VIRGIN  
      CULLEN AT THE ABOVE ADDRESS.                                      VIRGIN  
                                                                        VIRGIN  
      OUTPUT FORMAT                                                     VIRGIN  
      -------------                                                     VIRGIN  
      FOR ALL VERSIONS OF THIS PROGRAM PRIOR TO VERSION 92-1 OUTPUT WAS VIRGIN  
      IN TABULAR FORM.                                                  VIRGIN  
                                                                        VIRGIN  
      FOR VERSION 92-1 AND LATER VERSIONS OF THIS CODE ALL OUTPUT IS IN VIRGIN  
      THE PROGRAM PLOTTAB FORMAT TO ALLOW RESULTS TO BE EASILY PLOTTED. VIRGIN  
      FOR A COPY OF PROGRAM PLOTTAB CONTACT D.E. CULLEN AT THE ABOVE    VIRGIN  
      ADDRESS.                                                          VIRGIN  
                                                                        VIRGIN  
      TALLY GROUPS                                                      VIRGIN  
      ------------                                                      VIRGIN  
      THE TALLY GROUP STRUCTURE MAY BE ANY SET OF MONONTONICALLY        VIRGIN  
      INCREASING ENERGY BOUNDARIES. THERE MAY BE UP TO 2000 TALLY       VIRGIN  
      GROUPS. BY USING THE INPUT PARAMETERS THE USER MAY SPECIFY ANY    VIRGIN  
      ARBITRARY TALLY GROUP STRUCTURE OR SELECT ONE OF THE FOLLOWING    VIRGIN  
      BUILT-IN GROUP STRUCTURES.                                        VIRGIN  
                                                                        VIRGIN  
      (0) TART 175 GROUPS                                               VIRGIN  
      (1) ORNL  50 GROUPS                                               VIRGIN  
      (2) ORNL 126 GROUPS                                               VIRGIN  
      (3) ORNL 171 GROUPS                                               VIRGIN  
      (4) SAND-II 620 GROUPS - 1.0D-4 eV UP TO 18 MEV                   VIRGIN  
      (5) SAND-II 640 GROUPS - 1.0D-4 eV UP TO 20 MEV                   VIRGIN  
      (6) WIMS 69 GROUPS                                                VIRGIN  
      (7) GAM-I 68 GROUPS                                               VIRGIN  
      (8) GAM-II 99 GROUPS                                              VIRGIN  
      (9) MUFT 54 GROUPS                                                VIRGIN  
     (10) ABBN 28 GROUPS                                                VIRGIN  
     (11) TART 616 GROUPS TO  20 MeV                                    VIRGIN  
     (12) TART 700 GROUPS To   1 GeV                                    VIRGIN  
     (13) SAND-II 665 GROUPS - 1.0D-5 eV UP TO 18 MEV                   VIRGIN  
     (14) SAND-II 685 GROUPS - 1.0D-5 eV UP TO 20 MEV                   VIRGIN  
     (15) TART 666 GROUPS TO 200 MeV                                    VIRGIN  
     (16) SAND-II 725 GROUPS - 1.0D-5 eV UP TO  60 MEV                  VIRGIN  
     (17) SAND-II 755 GROUPS - 1.0D-5 eV UP TO 150 MEV                  VIRGIN  
     (18) SAND-II 765 GROUPS - 1.0D-5 eV UP TO 200 MEV                  VIRGIN  
     (19) UKAEA  1102 GROUPS - 1.0D-5 eV UP TO 1 GeV                    VIRGIN  
                                                                        VIRGIN  
      INCIDENT SPECTRUM                                                 VIRGIN  
      -----------------                                                 VIRGIN  
      THE INCIDENT SPECTRUM MAY BE ANY TABULATED FUNCTION THAT IS       VIRGIN  
      GIVEN BY A SET OF POINTS THAT IS MONOTONICALLY INCREASING IN      VIRGIN  
      ENERGY AND LINEAR-LINEAR INTERPOLABLE IN ENERGY-SPECTRUM          VIRGIN  
      BETWEEN TABULATED POINTS. THERE IS NO LIMIT TO THE NUMBER OF      VIRGIN  
      POINTS USED TO DESCRIBE THE SPECTRUM. THERE ARE FIVE BUILT-IN     VIRGIN  
      OPTIONS FOR THE SPECTRUM.                                         VIRGIN  
                                                                        VIRGIN  
      (1) CONSTANT...ENERGY INDEPENDENT (INPUT 0)                       VIRGIN  
      (2) 1/E (INPUT 1)                                                 VIRGIN  
      (3) BLACKBODY - PHOTON SPECTRUM                                   VIRGIN  
      (4) BLACKBODY - ENERGY SPECTRUM (E TIMES THE PHOTON SPECTRUM)     VIRGIN  
      (5) TRANSMITTED SPECTRUM FROM PREVIOUS CASE                       VIRGIN  
                                                                        VIRGIN  
      NORMALIZATION OF SPECTRUM                                         VIRGIN  
      -------------------------                                         VIRGIN  
      ANY INCIDENT SPECTRUM, EITHER READ AS INPUT OR ONE OF THE         VIRGIN  
      BUILT-IN SPECTRA, WILL BE NORMALIZED TO UNITY WHEN INTEGRATED     VIRGIN  
      OVER THEIR ENTIRE ENERGY RANGE.                                   VIRGIN  
                                                                        VIRGIN  
      TRANSMITTED SPECTRA WILL NOT BE RE-NORMALIZED, SINCE IT ALREADY   VIRGIN  
      INCLUDES THE NORMALIZATION OF THE INCIDENT SPECTRUM.              VIRGIN  
                                                                        VIRGIN  
      NOTE, INCIDENT SPECTRA IS NORMALIZED TO UNITY OVER THEIR ENTIRE   VIRGIN  
      ENERGY RANGE - NOT OVER THE ENERGY RANGE OF THE GROUPS. IF THE    VIRGIN  
      ENERGY RANGE OF THE GROUPS IS LESS THAN THAT OF THE SPECTRUM      VIRGIN  
      ONLY THAT PORTION OF THE SPECTRUM WILL BE USED AND THIS WILL      VIRGIN  
      NOT BE RE-NORMALIZED TO UNITY.                                    VIRGIN  
                                                                        VIRGIN  
      COMPOSITION OF A LAYER                                            VIRGIN  
      ----------------------                                            VIRGIN  
      YOU MAY RUN PROBLEMS INVOLVING                                    VIRGIN  
      1) A LAYER OF UNIFORM DENSITY - DENSITY FOR ATTENUATION IS THAT   VIRGIN  
         OF THE TOTAL. DENSITY FOR REACTIONS IS THAT OF THE REACTION.   VIRGIN  
      2) A LAYER OF UNIFORM DENSITY - DENSITY IS THE SUM OF THE TOTAL   VIRGIN  
         AND REACTION DENSITIES - THE SUM OF THE CROSS SECTIONS IS      VIRGIN  
         USED FOR ATTENUATION AND REACTIONS.                            VIRGIN  
      3) A LAYER OF VARYING DENSITY BASED ON A UNIFORM TOTAL DENSITY    VIRGIN  
         PLUS A VARIATION BETWEEN 0 AND A MAXIMUM BASED ON THE          VIRGIN  
         REACTION DENSITY - 0 AT 0 THICKNESS AND MAXIMUM AT MAXIMUM     VIRGIN  
         THICKNESS. IN THIS CASE THE AVERAGE REACTION DENSITY IS EQUAL  VIRGIN  
         TO THE INPUT REACTION DENSITY. THE VARIATION IN REACTION       VIRGIN  
         DENSITY CAN BE LINEAR, SQUARE OR CUBIC.                        VIRGIN  
      4) A LAYER OF VARYING DENSITY BASED ON A TOTAL DENSITY WHICH      VIRGIN  
         VARYING FROM MAXIMUM AT 0 THICKNESS TO 0 AT MAXIMUM THICKNESS  VIRGIN  
         PLUS A REACTION DENSITY WHICH VARIES FROM 0 AT 0 THICKNESS     VIRGIN  
         TO MAXIMUM AT MAXIMUM THICKNESS. IN THIS CASE THE AVERAGE      VIRGIN  
         DENSITY OF THE TOTAL AND REACTION WILL BOTH BE EQUAL TO THE    VIRGIN  
         INPUT TOTAL AND REACTION DENSITIES. THE VARIATION IN TOTAL     VIRGIN  
         AND REACTION DENSITY CAN BE LINEAR, SQUARE OR CUBIC.           VIRGIN  
                                                                        VIRGIN  
      IN THE FIRST CASE THE TWO REQUESTED CROSS SECTIONS ARE CONSIDERED VIRGIN  
      TO BE INDEPENDENT - THE TOTAL CROSS SECTION IS USED TO CALCULATE  VIRGIN  
      ATTENUATION AND THE REACTION CROSS SECTION IS USED TO CALCULATE   VIRGIN  
      REACTIONS, E.G., TRANSMISSION THROUGH NATURAL URANIUM (THE TOTAL  VIRGIN  
      CROSS SECTION SHOULD BE THAT OF NATURAL URANIUM) AND REACTIONS    VIRGIN  
      IN A U-235 DETECTOR (THE REACTION CROSS SECTION SHOULD BE THAT OF VIRGIN  
      U-235).                                                           VIRGIN  
                                                                        VIRGIN  
      IN THE OTHER THREE CASES THE TWO REQUESTED CROSS SECTIONS ARE     VIRGIN  
      TREATED AS TWO CONSTITUENTS OF A MIXTURE OF TWO MATERIALS AND     VIRGIN  
      THE TWO CROSS SECTIONS ARE USED BOTH TO DEFINE A TOTAL CROSS      VIRGIN  
      SECTION FOR ATTENUATION AND A REACTION CROSS SECTION TO DEFINE    VIRGIN  
      REACTIONS. IN THESE CASES THE MIXTURE WILL VARY CONTINUOUSLY,     VIRGIN  
      E.G., IN CASE 4) HALF WAY THROUGH THE LAYER THE COMPOSITION WILL  VIRGIN  
      BE 1/2 THE MATERIAL DEFINED BY THE TOTAL AND 1/2 THE MATERIAL     VIRGIN  
      BASED ON THE REACTION. IN THESE CASES RATHER THAN THINKING OF     VIRGIN  
      THE TWO CROSS SECTIONS AS A TOTAL AND REACTION CROSS SECTION,     VIRGIN  
      IT IS BETTER TO THINK OF THEM AS THE TOTAL CROSS SECTIONS FOR     VIRGIN  
      MATERIALS A AND B AND THE CALCULATED REACTIONS WILL BE BASED      VIRGIN  
      ON THESE TWO TOTAL CROSS SECTIONS.                                VIRGIN  
                                                                        VIRGIN  
      MULTIPLE LAYERS                                                   VIRGIN  
      ---------------                                                   VIRGIN  
      THIS CODE MAY BE USED TO RUN EITHER A NUMBER OF INDEPENDENT       VIRGIN  
      PROBLEMS, EACH INVOLVING TRANSMISSION THROUGH A SINGLE LAYER OF   VIRGIN  
      MATERIAL, OR TRANSMISSION THROUGH A NUMBER OF LAYERS ONE AFTER    VIRGIN  
      THE OTHER.                                                        VIRGIN  
                                                                        VIRGIN  
      IN THE CASE OF MULTIPLE LAYERS, ONE LAYER AFTER ANOTHER, THE      VIRGIN  
      TRANSMITTED ENERGY DEPENDENT SPECTRUM IS USED AS THE INCIDENT     VIRGIN  
      SPECTRUM FOR THE NEXT LAYER. THERE IS NO LIMIT TO THE NUMBER      VIRGIN  
      OF LAYERS WHICH MAY BE USED - EACH LAYER IS TREATED AS A          VIRGIN  
      COMPLETELY INDEPENDENT PROBLEM WITH A DEFINED INCIDENT SOURCE,    VIRGIN  
      AND AS SUCH THE CYCLE OF TRANSMISSION THROUGH EACH LAYER AND      VIRGIN  
      USING THE TRANSMITTED SPECTRUM AS THE INCIDENT SPECTRUM FOR THE   VIRGIN  
      NEXT LAYER MAY BE REPEATED ANY NUMBER OF TIMES.                   VIRGIN  
                                                                        VIRGIN  
      REMEMBER - THE INCIDENT SPECTRUM IS ASSUMED TO BE LINEARLY        VIRGIN  
      INTERPOLABLE IN ENERGY AND SPECTRUM BETWEEN THE ENERGIES AT       VIRGIN  
      WHICH IT IS TABULATED. THE TRANSMITTED SPECTRUM WILL BE TABULATED VIRGIN  
      AT THE UNION OF ALL ENERGIES OF THE INCIDENT SPECTRUM AND CROSS   VIRGIN  
      SECTIONS (TOTAL AND REACTION). IN ORDER TO INSURE THE ACCURACY    VIRGIN  
      OF THE RESULT WHEN PERFORMING MULTIPLE LAYER CALCULATION BE SURE  VIRGIN  
      TO SPECIFY THE INCIDENT SPECTRUM ON THE FIRST LAYER TO SUFFICIENT VIRGIN  
      DETAIL (ENOUGH ENERGY POINTS CLOSELY SPACED TOGETHER) IN ORDER TO VIRGIN  
      ALLOW THE TRANSMITTED SPECTRUM TO BE ACCURATELY REPRESENTED BY    VIRGIN  
      LINEAR INTERPOLATION BETWEEN SUCCESSIVE ENERGY POINTS - THERE IS  VIRGIN  
      NO LIMIT TO THE NUMBER OF POINTS ALLOWED IN THE INCIDENT SPECTRUM,VIRGIN  
      SO IF YOU ARE IN DOUBT, SIMPLY USE MORE ENERGY POINTS TO SPECIFY  VIRGIN  
      THE INCIDENT SPECTRUM.                                            VIRGIN  
                                                                        VIRGIN  
      RESULT OUTPUT UNITS                                               VIRGIN  
      -------------------                                               VIRGIN  
      FLUX      = EXACTLY AS CALCULATED                                 VIRGIN  
      REACTIONS = 1/CM OR 1/GRAM                                        VIRGIN  
      AVERAGE   = 1/CM - MACROSCOPIC UNITS                              VIRGIN  
      CROSS                                                             VIRGIN  
      SECTION                                                           VIRGIN  
                                                                        VIRGIN  
      THICKNESS AND DENSITY                                             VIRGIN  
      ---------------------                                             VIRGIN  
      THE UNCOLLIDED CALCULATION ONLY DEPENDS ON THE PRODUCT OF         VIRGIN  
      THICKNESS AND DENSITY (I.E. GRAMS PER CM SQUARED). THIS FACT      VIRGIN  
      MAY BE USED TO SIMPLIFY INPUT BY ALLOWING THE THICKNESS AND       VIRGIN  
      DENSITY TO BE GIVEN EITHER AS CM AND GRAMS/CC RESPECTIVELY        VIRGIN  
      OR ELSE TO GIVE THICKNESS IN GRAMS/(CM*CM) AND INPUT A            VIRGIN  
      DENSITY OF 1.0 - OR IN ANY OTHER CONVENIENT UNITS AS LONG AS      VIRGIN  
      THE PRODUCT OF THICKNESS AND DENSITY IS IN THE CORRECT GRAMS      VIRGIN  
      PER CENTIMETER SQUARED.                                           VIRGIN  
                                                                        VIRGIN  
      GRAMS/(CM*CM) ARE RELATED TO ATOMS/BARN THROUGH THE RELATIONSHIP  VIRGIN  
                                                                        VIRGIN  
      GRAMS/(CM*CM)=(ATOMS/BARN)*(GRAMS/MOLE)*(MOLE/ATOM)               VIRGIN  
                                                                        VIRGIN  
      OR...                                                             VIRGIN  
                                                                        VIRGIN  
      GRAMS/(CM*CM)=(ATOMS/BARN)*(ATOMIC WEIGHT)/0.602                  VIRGIN  
                                                                        VIRGIN  
      CROSS SECTIONS AT A SPACE POINT AND OPTICAL THICKNESS             VIRGIN  
      -----------------------------------------------------             VIRGIN  
      THIS PROGRAM ALLOWS LAYERS OF EITHER UNIFORM DENSITY OR           VIRGIN  
      CONTINUOUSLY VARYING DENSITY. THE DENSITY CAN BE ONE OF THE       VIRGIN  
      FOLLOWING FORMS,                                                  VIRGIN  
      1) C                   = UNIFORM DENSITY                          VIRGIN  
      2) C*2*(X/T)           = LINEAR VARIATION FROM 0 TO C             VIRGIN  
      3) C*(2-2*(X/T))       = LINEAR VARIATION FROM C TO 0             VIRGIN  
      4) C*3*(X/T)**2        = SQUARE VARIATION FROM 0 TO C             VIRGIN  
      5) C*(3-3*(X/T)**2)/2  = SQUARE VARIATION FROM C TO 0             VIRGIN  
      6) C*4*(X/T)**3        = CUBIC VARIATION FROM 0 TO C              VIRGIN  
      7) C*(4-4*(X/T)**3)/3  = CUBIC VARIATION FROM C TO 0              VIRGIN  
                                                                        VIRGIN  
      IN ORDER TO CALCULATE REACTIONS AT A POINT THE MICROSCOPIC        VIRGIN  
      REACTION CROSS SECTION NEED MERELY BE SCALED BY THESE DENSITIES.  VIRGIN  
                                                                        VIRGIN  
      IN ORDER TO CALCULATE TRANSMISSION WE MUST DEFINE THE OPTICAL     VIRGIN  
      PATH LENGTH WHICH MAY BE DEFINED BY INTEGRATING EACH OF THE       VIRGIN  
      ABOVE DENSITY FORMS TO FIND,                                      VIRGIN  
      1) C*X                                                            VIRGIN  
      2) C*X*(X/T)                                                      VIRGIN  
      3) C*X*(2-(X/T))                                                  VIRGIN  
      4) C*X*(X/T)**2                                                   VIRGIN  
      5) C*X*(3-(X/T)**2)/2                                             VIRGIN  
      6) C*X*(X/T)**3                                                   VIRGIN  
      7) C*X*(4-(X/T)**3))/3                                            VIRGIN  
                                                                        VIRGIN  
      IN ORDER TO CALCULATE TRANSMISSION TO A POINT THE MICROSCOPIC     VIRGIN  
      TOTAL CROSS SECTION NEED MERELY BE SCALED BY THESE DENSITIES      VIRGIN  
      TO DEFINE THE OPTICAL PATH LENGTH.                                VIRGIN  
                                                                        VIRGIN  
      THE VARIATION OF THE DENSITY THROUGH THE LAYER MAY BE DEFINED     VIRGIN  
      BY SETTING X = 0 OR X = T TO FIND,                                VIRGIN  
         X = 0      X = T                                               VIRGIN  
         -----      -----                                               VIRGIN  
      1) C          C                                                   VIRGIN  
      2) 0          2*C                                                 VIRGIN  
      3) 2*C        0                                                   VIRGIN  
      4) 0          3*C                                                 VIRGIN  
      5) 3*C/2      0                                                   VIRGIN  
      6) 0          4*C                                                 VIRGIN  
      7) 4*C/3      0                                                   VIRGIN  
                                                                        VIRGIN  
      THE OPTICAL PATH THROUGH A LAYER OF THICKNESS T MAY BE DEFINED    VIRGIN  
      FROM THE ABOVE EXPRESSIONS BY SETTING X=T TO FIND THAT IN ALL     VIRGIN  
      CASES THE ANSWER WILL BY C*T. THE CONSTANTS IN THE ABOVE          VIRGIN  
      EXPRESSIONS HAVE BEEN INTRODUCED IN ORDER TO FORCE THIS RESULT.   VIRGIN  
      WITH THESE FACTORS THE OPTICAL PATH LENGTH THROUGH THE LAYER      VIRGIN  
      WILL EXACTLY CORRESPOND TO AN AVERAGE DENSITY CORRESPONDING TO    VIRGIN  
      THAT INPUT FOR THE TOTAL AND/OR REACTION, I.E., C CORRESPONDS     VIRGIN  
      TO THE INPUT DENSITY.                                             VIRGIN  
                                                                        VIRGIN  
      NOTE - FOR THE SAME OPTICAL PATH LENGTHS THROUGH THE LAYER THE    VIRGIN  
      TRANSMISSION WILL BE EXACTLY THE SAME. HOWEVER, VARYING THE       VIRGIN  
      DENSITY WILL ALLOW YOU TO MODIFY THE REACTION RATES AT SPECIFIC   VIRGIN  
      DEPTHS INTO THE LAYER.                                            VIRGIN  
                                                                        VIRGIN  
      COMPUTATION OF INTEGRALS                                          VIRGIN  
      ------------------------                                          VIRGIN  
      STARTING FROM TOTAL CROSS SECTIONS, REACTION CROSS SECTIONS AND   VIRGIN  
      A SOURCE SPECTRUM ALL OF WHICH ARE GIVEN IN TABULAR FORM WITH     VIRGIN  
      LINEAR INTERPOLATION BETWEEN TABULATED POINTS ALL REQUIRED        VIRGIN  
      INTEGRALS CAN BE DEFINED BY ANALYTICAL EXPRESSIONS INVOLVING      VIRGIN  
      NOTHING MORE COMPLICATED THAN EXPONENTIALS. THE INTEGRALS THAT    VIRGIN  
      MUST BE EVALUATED ARE OF THE FORM...                              VIRGIN  
                                                                        VIRGIN  
      FLUX                                                              VIRGIN  
      ----                                                              VIRGIN  
      (INTEGRAL EK TO EK+1) (S(E)* EXP(-XCT(E)*Z)*DE)                   VIRGIN  
                                                                        VIRGIN  
      REACTIONS                                                         VIRGIN  
      ---------                                                         VIRGIN  
      (INTEGRAL EK TO EK+1) (S(E)*XCR(E)*EXP(-XCT(E)*Z)*DE)             VIRGIN  
                                                                        VIRGIN  
      WHERE..                                                           VIRGIN  
      EK TO EK+1 = LONGEST ENERGY INTERVAL OVER WHICH S(E), XCT(E) AND  VIRGIN  
                   XCR(E) ARE ALL LINEARLY INTERPOLABLE.                VIRGIN  
      S(E)       = ENERGY DEPENDENT WEIGHTING SPECTRUM                  VIRGIN  
      XCR(E)     = REACTION CROSS SECTION                               VIRGIN  
      XCT(E)     = OPTICAL PATH LENGTH (BASED ON TOTAL CROSS SECTION)   VIRGIN  
      Z          = MATERIAL THICKNESS                                   VIRGIN  
                                                                        VIRGIN  
      S(E), XCR(E) AND XCT(E) ARE ALL ASSUMED TO BE GIVEN IN TABULAR    VIRGIN  
      FORM WITH LINEAR INTERPOLATION USED BETWEEN TABULATED POINTS.     VIRGIN  
      IN OTHER WORDS BETWEEN TABULATED POINTS EACH OF THESE THREE IS    VIRGIN  
      DEFINED BY A FUNCTION OF THE FORM...                              VIRGIN  
                                                                        VIRGIN  
      F(E)=((E - EK)*FK+1 + (EK+1 - E)*FK)/(EK+1 - EK)                  VIRGIN  
                                                                        VIRGIN  
      EACH OF THESE THREE CAN BE CONVERTED TO NORMAL FORM BY THE        VIRGIN  
      CHANGE OF VARIABLES....                                           VIRGIN  
                                                                        VIRGIN  
      X=(E - 0.5*(EK+1 + EK))/(EK+1 - EK)                               VIRGIN  
                                                                        VIRGIN  
      IN WHICH CASE X WILL VARY FROM -1 (AT EK) TO +1 (AT EK+1) AND     VIRGIN  
      EACH FUNCTION REDUCES TO THE NORMAL FORM...                       VIRGIN  
                                                                        VIRGIN  
      F(X)=0.5*(FK*(1 - X) + FK+1*(1 + X))                              VIRGIN  
          =0.5*(FK+1 + FK) + 0.5*(FK+1 - FK)*X                          VIRGIN  
                                                                        VIRGIN  
      BY DEFINING THE AVERAGE VALUE AND 1/2 THE CHANGE ACROSS THE       VIRGIN  
      INTERVAL.                                                         VIRGIN  
                                                                        VIRGIN  
      AVF=0.5*(FK+1 + FK)                                               VIRGIN  
      DF= 0.5*(FK+1 - FK)                                               VIRGIN  
      DE= 0.5*(EK+1 - EK)                                               VIRGIN  
                                                                        VIRGIN  
      EACH OF THE THREE FUNCTIONS REDUCES TO THE SIMPLE FORM...         VIRGIN  
                                                                        VIRGIN  
      F(X)=AVF+DF*X                                                     VIRGIN  
                                                                        VIRGIN  
      AND THE TWO REQUIRED INTEGRALS REDUCE TO...                       VIRGIN  
                                                                        VIRGIN  
      FLUX                                                              VIRGIN  
      ----                                                              VIRGIN  
      DE*EXP(-AVXCT*Z) * (INTEGRAL -1 TO +1)                            VIRGIN  
      ((AVS+DS*X)*EXP(-DXCT*Z*X)*DX)                                    VIRGIN  
                                                                        VIRGIN  
      REACTION                                                          VIRGIN  
      --------                                                          VIRGIN  
      DE*EXP(-AVXCT*Z) * (INTEGRAL -1 TO +1)                            VIRGIN  
      ((AVS*AVXCR+(AVS*DXCR+AVXCR*DS)*X+DS*DXCR*X*X)*EXP(-DXCT*Z*X)*DX) VIRGIN  
                                                                        VIRGIN  
      WHERE                                                             VIRGIN  
                                                                        VIRGIN  
      AVXCT   = AVERAGE VALUE OF THE TOTAL CROSS SECTION                VIRGIN  
      AVXCR   = AVERAGE VALUE OF THE REACTION CROSS SECTION             VIRGIN  
      AVS     = AVERAGE VALUE OF THE SOURCE                             VIRGIN  
      DXCT    = 1/2 THE CHANGE IN THE TOTAL CROSS SECTION               VIRGIN  
      DXCR    = 1/2 THE CHANGE IN THE REACTION CROSS SECTION            VIRGIN  
      DS      = 1/2 THE CHANGE IN THE SOURCE                            VIRGIN  
      DE      = 1/2 THE CHANGE IN THE ENERGY                            VIRGIN  
                                                                        VIRGIN  
      NOTE THAT IN THIS FORM THE ENERGY ONLY APPEARS IN FRONT OF THE    VIRGIN  
      INTEGRALS AND THE INTEGRALS ARE EXPRESSED ONLY IN TERMS OF THE    VIRGIN  
      TABULATED VALUES OF S(E), XCT(E) AND XCR(E). IN PARTICULAR NO     VIRGIN  
      DERIVATIVES ARE USED, SO THAT THERE ARE NO NUMERICAL INSTABILITY  VIRGIN  
      PROBLEMS IN THE VACINITY OF DISCONTINUITIES IN S(E), XCT(E) OR    VIRGIN  
      XCR(E). INDEED, SINCE (EK+1 - EK) APPEARS IN FRONT OF THE INTEGRALVIRGIN  
      POINTS OF DISCONTINUITY AUTOMATICALLY MAKE ZERO CONTRIBUTION TO   VIRGIN  
      THE INTEGRALS.                                                    VIRGIN  
                                                                        VIRGIN  
      THE REQUIRED INTEGRALS CAN BE EXPRESSED IN TERMS OF THE THREE     VIRGIN  
      INTEGRALS IN NORMAL FORM....                                      VIRGIN  
                                                                        VIRGIN  
      F(A,N) = (INTEGRAL -1 TO 1) (X**N*EXP(-A*X)*DX), N=0,1 AND 2.     VIRGIN  
                                                                        VIRGIN  
      THESE THREE INTEGRALS CAN BE EVALUATED TO FIND...                 VIRGIN  
                                                                        VIRGIN  
      N=0                                                               VIRGIN  
      ---                                                               VIRGIN  
      F(A,0) = (EXP(A)-EXP(-A))/A                                       VIRGIN  
                                                                        VIRGIN  
      N=1                                                               VIRGIN  
      ---                                                               VIRGIN  
      F(A,1) = ((1-A)*EXP(A)-(1+A)*EXP(-A))/(A*A)                       VIRGIN  
                                                                        VIRGIN  
      N=2                                                               VIRGIN  
      ---                                                               VIRGIN  
      F(A,2) = ((2-2*A+A*A)*EXP(A)-(2+2*A+A*A)*EXP(-A))/(A*A*A)         VIRGIN  
                                                                        VIRGIN  
      HOWEVER THESE EXPRESSIONS ARE NUMERICALLY UNSTABLE FOR SMALL      VIRGIN  
      VALUES OF A. THEREFORE FOR SMALL A THE EXPONENTIAL IN THE         VIRGIN  
      INTEGRALS ARE EXPANDED IN A POWER SERIES...                       VIRGIN  
                                                                        VIRGIN  
      EXP(-AX)=1.0-(AX)+(AX)**2/2-(AX)**3/6+(AX)**4/24-........         VIRGIN  
              =(SUM K=0 TO INFINITY) (-AX)**K/(K FACTORIAL)             VIRGIN  
                                                                        VIRGIN  
      AND THE INTEGRAL REDUCES TO THE FORM....                          VIRGIN  
                                                                        VIRGIN  
      (SUM K=0 TO INFINITY) ((-A)**K/(K FACTORIAL)) *                   VIRGIN  
      (INTEGRAL -1 TO 1) (X**(N+K))*DX                                  VIRGIN  
                                                                        VIRGIN  
      WHICH CAN BE ANALYTICALLY EVAULATED TO FIND....                   VIRGIN  
      (K(N) = K FACTORIAL)                                              VIRGIN  
                                                                        VIRGIN  
      N=0                                                               VIRGIN  
      ---                                                               VIRGIN  
      F(A,0) = 2*(1+(A**2)/K(3)+(A**4)/K(5)+(A**6)/K(7)+....            VIRGIN  
                                                                        VIRGIN  
      N=1                                                               VIRGIN  
      ---                                                               VIRGIN  
      F(A,1) = -2*A*(2/K(3)+4*(A**2)/K(5)+6*(A**4)/K(7)+8*(A**6)/K(9)+..VIRGIN  
                                                                        VIRGIN  
      N=2                                                               VIRGIN  
      ---                                                               VIRGIN  
      F(A,2) = 2*(2/K(3)+3*4*(A**2)/K(5)+5*6*(A**4)/K(7)+               VIRGIN  
               7*8*(A**6)/K(9)+....                                     VIRGIN  
                                                                        VIRGIN  
      THESE EXPANSIONS ARE USED WHEN THE ABSOLUTE VALUE OF A IS LESS    VIRGIN  
      THAN 0.1. BY TRUNCATING THE ABOVE SERIES BEFORE A**8 THE ERROR    VIRGIN  
      RELATIVE TO THE LEADING TERM OF THE SERIES WILL BE 10**(-10),     VIRGIN  
      YIELDING 10 DIGIT ACCURACY.                                       VIRGIN  
                                                                        VIRGIN  
      AFTER EVALUATING THE ABOVE FUNCTIONS, EITHER DIRECTLY OR BY USING VIRGIN  
      THE EXPANSION THE TWO REQUIRED INTEGRALS CAN BE WRITTEN AS...     VIRGIN  
                                                                        VIRGIN  
      FLUX                                                              VIRGIN  
      ----                                                              VIRGIN  
      DE*EXP(-AVXCT*Z)*(AVS*F(A,0) + DS*F(A,1))                         VIRGIN  
                                                                        VIRGIN  
      REACTIONS                                                         VIRGIN  
      ---------                                                         VIRGIN  
      DE*EXP(-AVXCT*Z)*                                                 VIRGIN  
      (AVS*AVXCR*F(A,0) + (AVS*DXCR+AVXCR*DS)*F(A,1) + DS*DXCR*F(A,2))  VIRGIN  
                                                                        VIRGIN  
      INPUT FILES                                                       VIRGIN  
      -----------                                                       VIRGIN  
      FILENAME  UNIT  DESCRIPTION                                       VIRGIN  
      --------  ----  -----------                                       VIRGIN  
      INPUT       2   INPUT LINES                                       VIRGIN  
      ENDFIN     10   EVALUATED DATA IN ENDF/B FORMAT                   VIRGIN  
                                                                        VIRGIN  
      OUTPUT FILES                                                      VIRGIN  
      ------------                                                      VIRGIN  
      FILENAME  UNIT  DESCRIPTION                                       VIRGIN  
      --------  ----  -----------                                       VIRGIN  
      OUTPUT      3   OUTPUT LISTING                                    VIRGIN  
                                                                        VIRGIN  
      SCRATCH FILES                                                     VIRGIN  
      -------------                                                     VIRGIN  
      FILENAME  UNIT  DESCRIPTION                                       VIRGIN  
      --------  ----  -----------                                       VIRGIN  
      SCR1       12   REACTION, FLUX AND CROSS SECTION RESULTS (BCD)    VIRGIN  
                      (SORTED AT END OF RUN AND OUTPUT SEPARATELY)      VIRGIN  
      SCR2       13   TALLY GROUP ENERGY BOUNDARIES (BINARY)            VIRGIN  
      SCR3       14   SOURCE SPECTRUM (BINARY)                          VIRGIN  
      SCR4       15   TOTAL CROSS SECTION (BINARY)                      VIRGIN  
      SCR5       16   REACTION CROSS SECTION (BINARY)                   VIRGIN  
                                                                        VIRGIN  
      OPTIONAL STANDARD FILE NAMES (SEE SUBROUTINE FILIO1 AND FILEIO2)  VIRGIN  
      ----------------------------------------------------------------  VIRGIN  
      UNIT  FILE NAME   FORMAT                                          VIRGIN  
      ----  ----------  ------                                          VIRGIN  
        2   VIRGIN.INP   BCD                                            VIRGIN  
        3   VIRGIN.LST   BCD                                            VIRGIN  
       10   ENDFB.IN     BCD                                            VIRGIN  
     11-15  (SCRATCH)   BINARY                                          VIRGIN  
       16   PLOTTAB.CUR PLOTTAB OUTPUT FORMAT DATA                      VIRGIN  
                                                                        VIRGIN  
      INPUT LINES                                                       VIRGIN  
      -----------                                                       VIRGIN  
      ANY NUMBER OF CASES MAY BE RUN ONE AFTER THE OTHER. AFTER THE     VIRGIN  
      FIRST CASE HAS BEEN RUN THE FOLLOWING CASES MAY USE THE SAME      VIRGIN  
      THICKNESSES, GROUP STRUCTURE AND SPECTRUM AS THE PRECEDING CASE.  VIRGIN  
      IN ADDITION THE TRANSMITTED SPECTRUM FROM ONE CASE MAY BE USED    VIRGIN  
      AS THE INCIDENT SPECTRUM IN THE NEXT CASE, TO ALLOW MULTIPLE      VIRGIN  
      LAYERS OF DIFFERENT MATERIALS.                                    VIRGIN  
                                                                        VIRGIN  
      LINE  COLS.  FORMAT  DESCRIPTION                                  VIRGIN  
      ----  -----  ------  ----------                                   VIRGIN  
         1   1-60   ENDF/B INPUT DATA FILENAME                          VIRGIN  
                      (STANDARD OPTION = ENDFB.IN)                      VIRGIN  
                                                                        VIRGIN  
      LEAVE THE DEFINITION OF THE FILENAMES BLANK - THE PROGRAM WILL    VIRGIN  
      THEN USE STANDARD FILENAMES.                                      VIRGIN  
                                                                        VIRGIN  
       2-3   1-72   18A4   TWO LINE TITLE DESCRIBING PROBLEM            VIRGIN  
         4   1- 6    I6    ZA (1000*Z+A) OF TARGET FOR TOTAL            VIRGIN  
             7-11    I5    MT OF TOTAL                                  VIRGIN  
            12-22   E11.4  DENSITY FOR TOTAL                            VIRGIN  
            23-28    I6    ZA (1000*Z+A) OF TARGET FOR REACTION         VIRGIN  
            29-33    I5    MT OF REACTION                               VIRGIN  
                           = 0 - NO REACTION CALCULATION (ONLY FLUX).   VIRGIN  
                           = GREATER THAN 0 - CALCULATE REACTIONS.      VIRGIN  
            34-44   E11.4  DENSITY FOR REACTION                         VIRGIN  
            45-50    I6    NUMBER OF TARGET THICKNESSES                 VIRGIN  
                           = GREATER THAN 0 = READ FROM INPUT           VIRGIN  
                             (1 TO 2000 ALLOWED)                        VIRGIN  
                           =  0 = SAME AS LAST CASE                     VIRGIN  
            51-55    I5    NUMBER OF TALLY GROUPS                       VIRGIN  
                           (REMEMBER NUMBER OF GROUP BOUNDARIES         VIRGIN  
                           IS ONE MORE THAN THE NUMBER OF GROUPS)       VIRGIN  
                           UP TO 2000 GROUPS ARE ALLOWED                VIRGIN  
                           BUILT-IN GROUP STRUCTURES.                   VIRGIN  
                           = GREATER THAN 0 = READ FROM INPUT           VIRGIN  
                           =  0 TART 175 GROUPS                         VIRGIN  
                           = -1 ORNL  50 GROUPS                         VIRGIN  
                           = -2 ORNL 126 GROUPS                         VIRGIN  
                           = -3 ORNL 171 GROUPS                         VIRGIN  
                           = -4 SAND-II 620 GROUPS..1.0D-4 eV TO 18 MEV VIRGIN  
                           = -5 SAND-II 640 GROUPS..1.0D-4 eV TO 20 MEV VIRGIN  
                           = -6 WIMS 69 GROUPS                          VIRGIN  
                           = -7 GAM-I 68 GROUPS                         VIRGIN  
                           = -8 GAM-II 99 GROUPS                        VIRGIN  
                           = -9 MUFT 54 GROUPS                          VIRGIN  
                           =-10 ABBN 28 GROUPS                          VIRGIN  
                           =-11 TART 616 GROUPS TO  20 MeV              VIRGIN  
                           =-12 TART 700 GROUPS TO   1 GeV              VIRGIN  
                           =-13 SAND-II 665 GROUPS..1.0D-5 eV TO 18 MEV VIRGIN  
                           =-14 SAND-II 685 GROUPS..1.0D-5 eV TO 20 MEV VIRGIN  
                           =-15 TART 666 GROUPS TO 200 MeV              VIRGIN  
                           =-16 SAND-II 725 GROUPS..1.0D-5 eV TO  60 MEVVIRGIN  
                           =-17 SAND-II 755 GROUPS..1.0D-5 eV TO 150 MEVVIRGIN  
                           =-18 SAND-II 765 GROUPS..1.0D-5 eV TO 200 MEVVIRGIN  
                           =-19 UKAEA  1102 GROUPS..1.0D-5 eV to   1 GeVVIRGIN  
            56-60    I5    NUMBER OF POINTS IN SOURCE SPECTRUM          VIRGIN  
                           (MUST BE AT LEAST TWO POINTS)                VIRGIN  
                           = GREATER THAN 1 = READ FROM INPUT           VIRGIN  
                           =  0 = SAME AS LAST CASE                     VIRGIN  
                           = -1 = CONSTANT (ENERGY INDEPENDENT)         VIRGIN  
                           = -2 = 1/E                                   VIRGIN  
                           = -3 = BLACKBODY - PHOTON SPECTRUM           VIRGIN  
                           = -4 = BLACKBODY - ENERGY SPECTRUM           VIRGIN  
                           = -5 = TRANSMITTED SPECTRUM FROM LAST CASE   VIRGIN  
                           NOTE, ALL SPECTRA, EXCEPT THE TRANSMITTED    VIRGIN  
                           SPECTRUM FROM THE LAST CASE, WILL BE         VIRGIN  
                           NORMALIZED SUCH THAT ITS INTEGRAL OVER       VIRGIN  
                           ENERGY WILL BE UNITY.                        VIRGIN  
            61-64  1X,3I1  SPATIALLY DEPENDENT OUTOUT                   VIRGIN  
                           = 0 = NO                                     VIRGIN  
                           = 1 = YES                                    VIRGIN  
                           FOR THE 3 QUANTITIES                         VIRGIN  
                           COLUMN 67 FLUX                               VIRGIN  
                                  68 REACTIONS                          VIRGIN  
                                  69 AVERAGE CROSS SECTION              VIRGIN  
            65-65    I1    ENERGY DEPENDENT OUTOUT                      VIRGIN  
                           = 0 = NONE                                   VIRGIN  
                           = 1 = INCIDENT SPECTRUM                      VIRGIN  
                           = 2 = TRANSMITTED SPECTRUM                   VIRGIN  
                           = 3 = INCIDENT REACTIONS                     VIRGIN  
                           = 4 = TRANSMIITED REACTIONS                  VIRGIN  
                           = 5 = TOTAL CROSS SECTION                    VIRGIN  
                           = 6 = REACTION CROSS SECTION                 VIRGIN  
         5   1-11   E11.4  BLACKBODY TEMPERATURE IN eV                  VIRGIN  
            12-22   E11.4  FLUX NORMALIZATION                           VIRGIN  
            23-33   E11.4  REACTION NORMALIZATION                       VIRGIN  
                           CALCULATIONS WILL BE BASED ON THE SPECTRUM   VIRGIN  
                           AND CROSS SECTIONS AS READ. AT OUTPUT THE    VIRGIN  
                           RESULTS WILL BE MULTIPLIED BY THESE          VIRGIN  
                           NORMALIZATION FACTORS.                       VIRGIN  
            34-44    I11   DENSITY PROFILE                              VIRGIN  
                           = 0 - UNIFORM - BASED ON TOTAL DENSITY       VIRGIN  
                           = 1 - UNIFORM - TOTAL + REACTION DENSITY     VIRGIN  
                           = 2 - TOTAL + LINEAR REACTION                VIRGIN  
                           = 3 - LINEAR (TOTAL + REACTION)              VIRGIN  
                           = 4 - TOTAL + SQUARE REACTION                VIRGIN  
                           = 5 - SQUARE (TOTAL + REACTION)              VIRGIN  
                           = 6 - TOTAL + CUBIC REACTION                 VIRGIN  
                           = 7 - CUBIC (TOTAL + REACTION)               VIRGIN  
       6-N   1-66  6E11.4  TARGET THICKNESSES IN CM                     VIRGIN  
                           IF SAME AS LAST CASE THIS SECTION IS NOT     VIRGIN  
                           INCLUDED IN THE INPUT.                       VIRGIN  
      VARY   1-66  6E11.4  TALLY GROUP ENERGY BOUNDARIES                VIRGIN  
                           (NUMBER OF BOUNDARIES IS ONE MORE THAN       VIRGIN  
                           THE NUMBER OF TALLY GROUPS)                  VIRGIN  
                           IF THE STANDARD OPTION (-14 TO 0) IS         VIRGIN  
                           SELECTED THIS SECTION IS NOT INCLUDED        VIRGIN  
                           IN THE INPUT                                 VIRGIN  
      VARY   1-66  6E11.4  SOURCE SPECTRUM IN ENERGY (eV)-SOURCE PAIRS  VIRGIN  
                           (MUST BE AT LEAST TWO POINTS)                VIRGIN  
                           IF STANDARD OPTION (-5 TO 0) IS SELECTED THISVIRGIN  
                           SECTION IS NOT INCLUDED IN THE INPUT         VIRGIN  
                                                                        VIRGIN  
      ANY NUMBER OF CASES MAY BE RUN ONE AFTER ANOTHER.                 VIRGIN  
                                                                        VIRGIN  
      EXAMPLE INPUT NO. 1                                               VIRGIN  
      -------------------                                               VIRGIN  
      CALCULATE THE UNCOLLIDED FLUX AND CAPTURE (MT=102) THROUGH        VIRGIN  
      30 CM OF IRON (DENSITY 7.87 G/CC). TALLY THE RESULTS USING        VIRGIN  
      THE TART 175 GROUP STRUCTURE. THE SOURCE WILL BE CONSTANT         VIRGIN  
      FROM 1 KEV TO 20 MEV. USE THE STANDARD ENDF/B INPUT DATA          VIRGIN  
      FILENAME.                                                         VIRGIN  
                                                                        VIRGIN  
      ENDFB.IN                                                          VIRGIN  
      IRON 0 TO 30 CM THICK.                                            VIRGIN  
      CONSTANT SOURCE FROM 1 KEV TO 20 MEV.                             VIRGIN  
       26000    1 7.8700D+ 0 26000  102 7.8700D+ 0     2    0    2 1100 VIRGIN  
       0.0000D+ 0 1.0000D+ 0 1.0000D+ 0          0 0.0000D+00           VIRGIN  
       0.0000D+00 3.0000D+01                                            VIRGIN  
       1.0000D+03 1.0000D+00 2.0000D+07 1.0000D+00                      VIRGIN  
                                                                        VIRGIN  
      EXAMPLE INPUT NO. 2                                               VIRGIN  
      -------------------                                               VIRGIN  
      CALCULATE THE UNCOLLIDED PHOTON FLUX THROUGH A MIXTURE OF SILICON VIRGIN  
      AND IRON FOR 100 MEV PHOTONS INCIDENT. THE TRANSMISSION WILL BE   VIRGIN  
      CALCULATED FOR 21 THICKNESSES VARYING BETWEEN 0 AND 1 CM. THERE   VIRGIN  
      WILL BE ONLY 1 TALLY GROUP SPANNING A VERY NARROW ENERGY RANGE    VIRGIN  
      NEAR 100 MEV, AND THE SOURCE SPECTRUM WILL BE CONSTANT OVER THE   VIRGIN  
      SAME ENERGY RANGE. USE THE STANDARD ENDF/B INPUT DATA FILENAME    VIRGIN  
      BY LEAVING THE FIRST INPUT LINE BLANK.                            VIRGIN  
                                                                        VIRGIN  
      (THIS IS A BLANK LINE TO USE THE STANDARD INPUT FILENAME)         VIRGIN  
      100 MEV PHOTONS                                                   VIRGIN  
      SILICON + 5 % IRON                                                VIRGIN  
       14000  521 2.30000+ 0 26000  521 1.15000- 1    21    1    2 1000 VIRGIN  
       0.00000+ 0 1.00000+ 0 1.00000+ 0          1 0.00000+00           VIRGIN  
       0.00000+00 5.00000-01 1.00000+00 1.50000+00 2.00000+00 2.50000+00VIRGIN  
       3.00000+00 3.50000+00 4.00000+00 4.50000+00 5.00000+00 5.50000+00VIRGIN  
       6.00000+00 6.50000+00 7.00000+00 7.50000+00 8.00000+00 8.50000+00VIRGIN  
       9.00000+00 9.50000+00 1.00000+01                                 VIRGIN  
       9.99000+ 7 1.00100+ 8                                            VIRGIN  
       9.99000+ 7 1.00000+ 4 1.00100+ 8 1.00000+ 4                      VIRGIN  
                                                                        VIRGIN  
 =======================================================================VIRGIN