======================================================================= 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 CHANGE Virgin  
                                  *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 feedback Virgin  
                                  *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 structure Virgin  
                                   using SUBROUTINE GROPE is identical   Virgin  
                                   for GROUPIE and VIRGIN.               Virgin  
                                  *All floating point parameters changed Virgin  
                                   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  
                                                                         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 INTEGRAL Virgin  
      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 MEV Virgin  
                           =-17 SAND-II 755 GROUPS..1.0D-5 eV TO 150 MEV Virgin  
                           =-18 SAND-II 765 GROUPS..1.0D-5 eV TO 200 MEV Virgin  
                           =-19 UKAEA  1102 GROUPS..1.0D-5 eV to   1 GeV Virgin  
            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 THIS Virgin  
                           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+00 Virgin  
       3.00000+00 3.50000+00 4.00000+00 4.50000+00 5.00000+00 5.50000+00 Virgin  
       6.00000+00 6.50000+00 7.00000+00 7.50000+00 8.00000+00 8.50000+00 Virgin  
       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