BETHE-BLOCH V1.2
                       RANGE & ENERGY LOSS LIBRARY
		        (Particle/Nuclear Physics)
                             by Tony Ambardar
                                 (c) 1995
                               ===========

DESCRIPTION:      The ionization energy loss of particles -- aside from 
                  electrons -- passing through matter can be described
		  using the Bethe-Bloch equation. BETHE-BLOCH V1.2 allows
		  the user to easily define various particles and media,
		  and then quickly calculate a range and energy loss.
		  It is written in ~50/50 SYSRPL/ASSEMBLY for speed.

LIBRARY #:        1600
SIZE:             5214 bytes
CHECKSUM:         # 9409 d

COMPATIBILITY:    S(X) and G(X). Note: BETHE-BLOCH makes use of two
                  unsupported entry points, which are not version dependent
		  according to documentation I have. It definitely works on
		  a GX Rev-P. But be safe: backup your HP48 before testing
		  this software.

DISCLAIMER:       This software is provided AS IS; the author assumes
                  NO responibility for the results of its use. Sale,
		  commercial distribution, or modification of this
		  software is NOT allowed without prior written 
		  permission of the author.

INSTALLATION:     Transfer file BETHE.SGX to HP48. Recall library to stack.
                  Store in favourite port. Turn calc off, then on. 
		  Also transfer data files BBMED and BBPAR to HP48, and
		  store where accessible by the library. Once installation
		  is complete, file BETHE.SGX may be deleted.
		  
If you use this software and have comments, questions, or suggestions
for improvement, please drop me a line: 

Tony Ambardar 
E-Mail: bird@triumf.ca

                             Display Layout
			     ==============
			     
                  Medium:  (current medium)
                Particle:  (current particle)
                Energy:    (current particle energy)
	        -dE/dx:    (energy loss per unit distance)
		    dX:    (medium thickness)
		    dE:    (total energy loss through distance dX)
	         Range:    (particle range in medium)
                _=_____=________________________		 
		|MEDIA|PRTCL|ENRG|dX|INFO?|QUIT|
		--------------------------------

         NOTE: some field are only active after pressing 'INFO?'
	 
	 
                             Key Definitions
			     ===============
			     
MEDIA:            Select current media using a sub-menu created from the
                  file BBMED (see description with BBPAR).
		  
PRTCL:            Select current particle from a sub-menu created from
                  file BBPAR ( see description of BBPAR later). Exit the
		  sub-menu by re-selecting the active key or pressing
		  'BETHE'.
		  
ENRG/MOM:         Input particle energy or momentum depending on the
                  current key label.
		  
(DELTA)X:         Input thickness of medium.

INFO?:            Calculate range of particle in medium, energy loss
                  traveling a distance (DELTA)X, and dE/dx at the initial
		  energy.
		  
QUIT:             Exit the program, saving current input parameters.

+/-:              Toggle between momentum- and energy-mode for display and
                  input.
		  
STO:              Update the current energy/momentum by adding the last
                  calculated energy loss. One can use this feature to step
		  a particle through several layers of material, for
		  example.
		  
ON/ATTN:          Exit the program, removing all saved input parameters
                  and files from the hidden directory.
		  

                               DATA FILES
			       ==========

         The particles and media available to the user are defined by
	 the files BBPART and BBMED. These can be easily edited to add
	 new media and particles. I've added a lot of error checking,
	 so don't worry too much about crashing your calculator through
	 incorrect input, or invalid particle or media data.
	 
	 
	 The data files are organized as follows:
	 
         ( NOTE: units are   MeV  -  grams  -  cm )
	 
	 BBPART  =  {  PART1  PART2  ...  }
	 
	 PARTn   =  {  Name(STRING)  Charge(FLOAT)  Mass(FLOAT)  }
	 
	 e.g.  BBPART  =  {  ...  {  "Pion"  1  139.6  }  ...  }
	 
	 
	 and
	 
	 
	 BBMED   =  {  MED1  MED2  ...  }
	 
	 MEDn    =  {  Name(STRING)  Density(FLOAT)  FORMULAn  }
	 
	 FORMULAn can be expressed in one of two ways:
	 
	         =  MolecularFormula(STRING) IONCONST
		 
		 IONCONST = { Element1(STRING) IonizationConstant1(FLOAT)
		              Element2(STRING) IonizationConstant2(FLOAT)
			      ...
		            }
		 
		 e.g. "C5H8O2" { "H" 0.000015 }
		 
		 or as a sequence of elements in the molecular unit:

		 =  ELEM1 ELEM2 ...
		 
		 ELEMn = {  AtomicNumber(FLOAT)  AtomMass(FLOAT)
		            NumberInMolecule(FLOAT) 
			    IonizationConstant(FLOAT)
			 }
		    
		 e.g. { 82 207 1 0.000823 }  ( this is lead i.e. "Pb1" )
		 
		 This second form is useful for isotopes e.g. deuterium
		 in deuterated polyethylene (CD2).
		 
		 Also, in both cases inclusion of ionization constants
		 is optional. Defaults are calculated if omitted.
	 
	 e.g. BBMED  =  {  ...
	                   {  "Quartz"  2.64  "SiO2"  }
			   ...
			   {  "CD2"  0.95  { 6 12 1} { 1 2 2 0.000015 }  }
			   ...
			}