p hi t s

PHITSBasic Lecture I:

Geometry and Source Definition

Multi-Purpose Particle and Heavy Ion Transport code System

title 1

Oct. 2015 revised

Purpose of This Lecture

Purpose 2

Learn input format of PHITS, and how to define simple geometry and source term

You can obtain this kind of results at the end of this lecture(Particle fluence around cylindrical water irradiated by 290 MeV proton beam)

• General Description • Geometry

• Source• Summary and Homework

Contents 3

Table of Contents

• General definition• How to define cell• Definitions of boxes and cylinders• SimpleGEO• How to add material

Format of PHITS input

General description 4

Calculation condition can be specified by text file

Basic formatkeyword （ parameter ） = value or character

[ Section Name ] ←start of this section

Input file consists of several sections

(“space” means nothing)

parameter1 parameter2 parameter3 …• Parameters are separated by “space”• You can write 200 characters in one line• Insert more than 6 spaces in successive line

or

Parameters can be given in mathematic equations: e.g. 1.0+exp(-2.0)

Input support command

5

*You can write sections in arbitrary order[ ]off　　　 skip this sectionqp:　　　 skip from this line to the next sectionq:　　　 equivalent to [end] sectionComment marks C in the first 5 column of the line $ and # in the middle of the line (but # cannot be used in the [cell] and [surface] sections)

General description

Main components of input


Three fundamental components

See sample input “lec01.inp”

• In the PHITS simulation, you have to specify the geometry of 3-dimensional virtual space and information of source particles, and then you can tally various quantities by simulating particle motions in the virtual space

　⇒ ①　 Geometry

　　　 ②　 Source

　　　 ③　 Tally

Result of the sample input


track_xz.eps phits.out

Display of the result

Summary of the calculation

Version Number


phits.out

PHITS Logo + Version information Input Echo

• Echo of the parameters specified in the input file• Description of the parameter and its default value is also written

Memory status• You can check how many memories are used in the calculation

Batch information (You will learn about “Batch” in Lecture 3) Summary of PHITS simulation

• Numbers of events such as source generation and nuclear reaction occurred

• Information on transported particles• Numbers of secondary particles generated• CPU time• Numbers of library data and reaction models used

Output File

Error information is usually given in the console Window,but occasionally in the output file!

[Title]title comments

[Parameters]define parameters

[Source]define source

[Material]define materials

[Surface]define surfaces

[Cell]define cells

[T-Track]track length tally

[T-3dshow]3d show tally

[End]

Sample input

9

This consists of 9 sections.

② SourceProduction of particles

① GeometryDefinition of 3D virtual space

③ Tally Observation of quantities

General description

lec01.inp

List of “section”

10General description

セクション名

[title]

[parameters]

[source]

[material]

[surface]

[cell]

[transform]

[temperature]

[mat time change]

[magnetic field]

[electro magnetic field]

[delta ray]

[super mirror]

[elastic option]

セクション名

[frag data]

[importance]

[weight window]

[forced collisions]

[brems bias]

[photon weight]

[volume]

[multiplier]

[mat name color]

[reg name]

[counter]

[timer]

[end]

※See PHITS manual sec. 4

List of tally

11

You can set several tallies at once to obtain various information on the particle transport.*See manual sec. 6 for each tally section.

General description

セクション名

[t-track]

[t-cross]

[t-heat]

[t-deposit]

[t-deposit2]

[t-yield]

[t-product]

[t-dpa]

[t-let]

セクション名

[t-sed]

[t-time]

[t-star]

[t-dchain]

[t-userdefined]

[t-gshow]

[t-rshow]

[t-3dshow]



Contents 12

Table of Contents


General definition

Geometry (General definition)

13

To make a 3-dimensional geometry, take the following three steps.1) Define materials in [Material] 2) Define surfaces of cells in [Surface]

3) Define cells with materials in [Cell]

Water(H2O) Aluminum (Al) sphere

surfacecuboid surface

water sphere

aluminum cuboid

water cylinder

Combine

cylinder surface

3D virtual space


14

You can use an infinite space. But, you have to define void or air regions explicitly. Furthermore, you also have to define a outer region of the virtual space.

3D virtual space in PHITS consists of cells defined in XYZ coordinate system.

X

Y

Z

[ M a t e r i a l ]mat[1] 1H 2 16O 1

[ S u r f a c e ] 10 so 10.

[ C e l l ] 100 1 -1.0 -10 101 -1 10

15

lec01.inp 1H : 16O = 2 : 1　　　⇒ H2O （ water ）

Define material

•1H 2.0 16O 1.0 (Positive density: Atomic ratio)

•1H -2.0/18.0 16O -16.0/18.0 (Negative density: mass ratio)

•1001 2.0 8016 1.0 (Atom can be expressed by Z*1000 + A)

Several ways to express material

Material number, (Atom & density)…


[ M a t e r i a l ]mat[1] 1H 2 16O 1

[ S u r f a c e ] 10 so 10.

[ C e l l ] 100 1 -1. -10 101 -1 10

Define surface

16

lec01.inp surface of sphere (so) having its center at the origin of the XYZ coordinate system with radius of 10 cm

• Surface number, Shape, Parameters • Parameters are expressed in the unit of “cm”

Various types of surfaces can be used in PHITS•so, sx, sy, sz, s

(sphere)•px, py, pz (plane)•cx, cy, cz (cylinder)•rpp (rectangular) etc. (see Manual 4.5)


[ M a t e r i a l ]mat[1] 1H 2 16O 1

[ S u r f a c e ] 10 so 10.

[ C e l l ] 100 1 -1.0 -10 101 -1 10

Define cell

17

lec01.inp 100: Cell number1 : Material number-1. : Material density = 1.0 g/cm3

(If positive, =1024 atoms/cm3)

-10 : Inside surface 10

101: Cell number-1 : Outer region (density is not necessary)10 : Outside surface 10

Cell number, material number, density, surface numbers


Confirmation of your geometry

18

lec01.inp [ P a r a m e t e r s ] icntl = 8file(6) = phits.out

track_xz.eps

Set 8when you confirmthe geometry

Procedure for confirming your geometry


1. Change “icntl” parameter in the [Parameters] section.

2. Execute PHITS3. See an eps file“track_xz.eps”

[ M a t e r i a l ]mat[1] 1H 2 16O 1

[ S u r f a c e ] 10 so 10.

[ C e l l ] 100 1 -1.0 -10 101 -1 10

Change the radius of the sphere to 20 cm.

Exercise 1

19

lec01.inp


Change the radius of the sphere to 20 cm.

Answers 1

20

lec01.inp


[ M a t e r i a l ]mat[1] 1H 2 16O 1

[ S u r f a c e ] 10 so 20.

[ C e l l ] 100 1 -1.0 -10 101 -1 10

track_xz.eps

Is the radius of the sphere 20 cm?

21

　　 In each course of PHITS tutorial, there are many exercises, but only one (or a few) input files are included in each folder.

　　 If you would like to skip some exercises, you can use the input files contained in “input/” folder, such as lec01-2.inp. For example, if you would like to do the exercise 3, please use “lec01-3.inp” in “input/” folder. “lec01-3.inp” includes all revisions that should have been done in exercises 1 and 2.


About Input File

• Define a surface of a sphere with 5 cm radius and its center in the origin of the XYZ coordinate system.

• “10” in the 1st line of [Surface] section is “surface number”. Let’s use “11” for new surface number.

Definition of a new surface

22

lec01.inp


[ M a t e r i a l ]mat[1] 1H 2 16O 1

[ S u r f a c e ] 10 so 20. 11 so 5.

[ C e l l ] 100 1 -1.0 -10 101 -1 10

• “100” in the 1st line of [Cell] section is “cell number”. Let’s use “102” for new cell number.

Exercise 2

23

lec01.inp


Add spherical water cell with 5 cm radius to the system.

[ M a t e r i a l ]mat[1] 1H 2 16O 1

[ S u r f a c e ] 10 so 20. 11 so 5.

[ C e l l ] 100 1 -1.0 -10 101 -1 10 102 *** *** ***

Answer 2

24Geometry (General definition)

Add spherical water cell with 5 cm radius to the system.

lec01.inp[ M a t e r i a l ]mat[1] 1H 2 16O 1

[ S u r f a c e ] 10 so 20. 11 so 5.

[ C e l l ] 100 1 -1.0 -10 101 -1 10 102 1 -1.0 -11

Some part of cell 100 overlaps cell 102. 　⇒ Overlapped region!!

PHITS always identifies the region where the tracing particle in, so PHITS confuses when one location is defined by more than 2 regions. (geometry error file: track_xz.err)

track_xz.eps

Overlapped region is painted in black.

Geometry error(undefined region)

25

You can use infinite space. But, you have to fill them with certain material (or define them as void).


Undefined region is painted in purple.(There may be cases where the other defined region disappeared.)

Geometry error file


26

When a geometry error occurs, PHITS outputs a error file (.err) where information on the error is outputted.

track_xz.err

Errors of cell definition in EPS Page No. = 1Overlapped Cell IDs x, y, z coodinates(Cells 0 0 indicate undefined region) 100 102 -4.847761E+00 1.234568E-11 -1.211940E+00 100 102 -4.847761E+00 1.234568E-11 -1.009950E+00 100 102 -4.847761E+00 1.234568E-11 -8.079602E-01・・・・・・・・・・・・

Cell numbers causing the error.

x, y, z coordinates where the geometry error occurs.

Even if only one error occurs, many lines are written.



Contents 27

Table of Contents


Cell can be defined by surfaces and cells using Boolean operators

How to define cell

Geometry 28

　　　　　　 example

-11(inside of the surface 11)

+11(outside of the surface 11) the surface number 11

[ M a t e r i a l ]mat[1] 1H 2 16O 1

[ S u r f a c e ] 10 so 20. 11 so 5.

[ C e l l ] 100 1 -1.0 -10 11 101 -1 10 102 1 -1.0 -11

Boolean operator （ AND ）

29

lec01.inp

Cells are defined by surface numbers with “blank” (AND).

Geometry

track_xz.epsTrue answer of the

2nd exercise.Inside of “10”and outside of “11”

Add ‘+11’ to the definition of the cell 100.(+ can be omissible.)

[ C e l l ] 100 1 -1.0 -10 #102 101 -1 10 102 1 -1.0 -11

Geometry 30

lec01.inp [ C e l l ] 100 1 -1.0 -10 11 101 -1 10 102 1 -1.0 -11

Exclude the region of the cell number 102 from the inside of the surface 10.

＊ Cells are usually defined by using surface numbers, but are also defined by cell numbers with #.

Rewrite another representation using #.

Boolean operator （ NOT ）You can use NOT (“#”) to exclude a region.

equivalent

**You have to use surface numbers inside “()”, will be mentioned later.

Extension of virtual space

Geometry 31

lec01.inp

3D virtual space should be wide enough to describe particle transport.

[ M a t e r i a l ]mat[1] 1H 2 16O 1

[ S u r f a c e ] 10 so 500. 11 so 5.

[ C e l l ] 100 1 -1.0 -10 #102 101 -1 10 102 1 -1.0 -11

track_xz.eps

Change 20cm to 500cm.

track_xz.eps

Exercise 3

32

lec01-3.inp （ use this file ）[ M a t e r i a l ]mat[1] 1H 2 16O 1

[ S u r f a c e ] 10 so 500. 11 so 5. 12 sz 11. 5.

[ C e l l ] 100 1 -1.0 -10 #102 #103 101 -1 10 102 1 -1.0 -11 103 1 -1.0 -12

sphere having its center in the XYZ coordinate (0, 0, 11) with radius of 5 cm

Geometry

Where is cell “103” in the right panel?

track_xz.eps

lec01.inp

[ M a t e r i a l ]mat[1] 1H 2 16O 1

[ S u r f a c e ] 10 so 500. 11 so 5. 12 sz 11. 5.

[ C e l l ] 100 1 -1.0 -10 #102 #103 101 -1 10 102 1 -1.0 -11 103 1 -1.0 -12

Answer 3

33Geometry

Where is cell “103” in the right panel?

sx, sy, sz can be used.Universal expression s is used with the XYZ coordinate of its center and its radius.

[ S u r f a c e ] 10 so 500. 11 so 5. 12 sz 8. 5.

[ C e l l ] 100 1 -1.0 -10 #102 #103 101 -1 10 102 1 -1.0 -11 103 1 -1.0 -12

Exercise 4

34

lec01.inp

Expected resulttrack_xz.eps

An overlap of the two spheres causes the geometry error (overlapped region).← Let’s exclude this overlap region from cells 102&103 and create a new cell 104

Change the center of this sphere

Geometry

Correct a geometry error.

[ S u r f a c e ] 10 so 500. 11 so 5. 12 sz 8. 5.

[ C e l l ] 100 1 -1.0 -10 #102 #103 #104 101 -1 10 102 1 -1.0 -11 12 103 1 -1.0 -12 11 104 1 -1.0 -11 -12

Answer 4

35

lec01.inp

track_xz.eps

Geometry

Correct a geometry error.

An example of answers

[ C e l l ] 100 1 -1.0 -10 #102 #103 #104 101 -1 10 102 1 -1.0 -11 12 103 1 -1.0 -12 11 104 1 -1.0 -11 -12

Boolean operator （ OR ）

36

lec01.inp

[ C e l l ] 100 1 -1.0 -10 #(-11 : -12) 101 -1 10 102 1 -1.0 -11 12 103 1 -1.0 -12 11 104 1 -1.0 -11 -12

Boolean operator “OR” is expressed by “:”.

equivalent

NOT(#) is easier to use, but it costs more memories in PCIt is better to express cells using “AND” and “OR” operators

Geometry (Boolean Operator)

*You have to use surface numbers inside “#()”.

Onion geometry

37

input/onion.inp[ M a t e r i a l ]mat[1] 1H 2 16O 1

[ S u r f a c e ] 11 so 5. 12 so 10. 13 so 15. 14 so 20. 15 so 25.

[ C e l l ] 101 1 -1. -11 102 1 -1. -12 #101 103 1 -1. -13 #101 #102 104 1 -1. -14 #101 #102 #103 105 1 -1. -15 #101 #102 #103 #104 106 1 -1. 15

A bad example of PHITS input file using unnecessary “#”s → Become time consuming!

[ M a t e r i a l ]mat[1] 1H 2 16O 1

[ S u r f a c e ] 11 so 5. 12 so 10. 13 so 15. 14 so 20. 15 so 25.

[ C e l l ] 101 1 -1. -11 102 1 -1. 11 -12 103 1 -1. 12 -13 104 1 -1. 13 -14 105 1 -1. 14 -15 106 1 -1. 15

Geometry (Boolean Operator)



Contents 38

Table of Contents


How to make a box

Geometry 39

A box can be defined using rpp

X

Y

Z

[ S u r f a c e ]　　　　・　　　　・　　　　・ 13 rpp xmin xmax ymin ymax zmin zmax

　xmin

xmax

ymaxymin

zmin

zmax

set minimum and maximum of x, y, z coordinates to define a box.*rpp is set in the [surface] section, because rpp corresponds to 6 faces of the box.

[ S u r f a c e ] 10 so 500. 11 so 5. 12 sz 8. 5. 13 rpp *** *** *** *** *** ***

[ C e l l ] 100 1 -1.0 -10 #102 #103 #104 *** 101 -1 10 102 1 -1.0 -11 12 103 1 -1.0 -12 11 104 1 -1.0 -11 -12 105 1 -1.0 ***

Geometry 40

lec01.inp

Let’s define a 10cm cube centered at (0,0,-11) using rpp.

• Set min. and max. to be -5.0cm and 5.0cm, respectively, for x and y, and min. and max. to be -16cm and -6.0cm, respectively, for z.

• Define the inside of the surface specified by rpp as a cell using a symbol -(minus).

Exercise 5

Let’s execute PHITS and see the result to confirm whether a cube is correctly defined or not.

Geometry 41

Answer 5

track_xz.eps

[ S u r f a c e ] 10 so 500. 11 so 5. 12 sz 8. 5. 13 rpp -5. 5. -5. 5. -16. -6.

[ C e l l ] 100 1 -1.0 -10 #102 #103 #104 #105 101 -1 10 102 1 -1.0 -11 12 103 1 -1.0 -12 11 104 1 -1.0 -11 -12 105 1 -1.0 -13

lec01.inp

Let’s define a 10cm cube centered at (0,0,-11) using rpp.

[ C e l l ] 100 1 -1.0 -10 #102 #103 #104 #105 101 -1 10 102 1 -1.0 -11 12 103 1 -1.0 -12 11 104 1 -1.0 -11 -12 105 1 -1.0 -13 -14

[ S u r f a c e ] 10 so 500. 11 so 5. 12 sz 8. 5. 13 rpp -5. 5. -5. 5. -16. -6. 14 px 3.0

ｐｘ： Perpendicular plane to X-axis

Geometry 42

lec01.inp

x

y

z

3

ｐｘ 3.0

Let’s add red texts and then execute PHITS.

Cells divided by a plane

X axisX=x0

＋ side－ side

To distinguish between two regions divided by a plane, symbols “+” or “-” are used.

Geometry 43

lec01.inp

track_xz.eps

Cell 105: inside of the surface 13 “AND” negative region of the surface 14.(A positive region of the surface 14 in the 10cm cube is cut.)

py and pz can be used.*Distinguish divided two regions by positive and negative senses.

Cells divided by a plane

[ C e l l ] 100 1 -1.0 -10 #102 #103 #104 #105 101 -1 10 102 1 -1.0 -11 12 103 1 -1.0 -12 11 104 1 -1.0 -11 -12 105 1 -1.0 -13 -14

[ S u r f a c e ] 10 so 500. 11 so 5. 12 sz 8. 5. 13 rpp -5. 5. -5. 5. -16. -6. 14 px 3.0

ｐｘ： Perpendicular plane to X-axis

How to make a cylinder

44

A cylinder can be defined using an infinite cylindrical tube and two planes

Geometry

[ C e l l ] 100 1 -1.0 -10 #102 #103 #104 #105 #106 101 -1 10 102 1 -1.0 -11 12 #106 103 1 -1.0 -12 11 #106 104 1 -1.0 -11 -12 #106 105 1 -1.0 -13 -14 #106 106 1 -1.0 -15 16 -17

Geometry 45

lec01.inp

• Add red texts in the [surface] and [cell] sections.• The cell 106 overlaps the cells 100, 102, 103, 104 and 105.

[ S u r f a c e ] 10 so 500. 11 so 5. 12 sz 8. 5. 13 rpp -7. 7. -7. 7. -19. -5 14 px 3.0 15 cz 1. 16 pz -19. 17 pz 19.

Exercise 6Let’s define a cylinder.

The inside and outside correspond to “-” and “+” symbols, respectively.

Let’s execute PHITS and see the result to confirm whether a cylinder is correctly defined or not.

Geometry 46

track_xz.eps

lec01.inp[ S u r f a c e ] 10 so 500. 11 so 5. 12 sz 8. 5. 13 rpp -7. 7. -7. 7. -19. -5 14 px 3.0 15 cz 1. 16 pz -19. 17 pz 19.

cell 107: a cylinder with a radius of 1.0cm and a height of 38cm.

Answer 6Let’s define a cylinder.

[ C e l l ] 100 1 -1.0 -10 #102 #103 #104 #105 #106 101 -1 10 102 1 -1.0 -11 12 #106 103 1 -1.0 -12 11 #106 104 1 -1.0 -11 -12 #106 105 1 -1.0 -13 -14 #106 106 1 -1.0 -15 16 -17

[ S u r f a c e ] 999 so 500. 11 so 5. 12 sz 8. 5. 101 px -3. 111 pz -19. 112 pz 19. 201 cz 1. 301 rpp -5. 5. -5. 5. -16. -6.

Rearrangement of Cell & Surface numbers

Geometry 47

lec01.inp

After making a part of geometries, you should rearrange the cell and surface numbers according to your rules.

For example,rearrange the numbers in ascending order in each px, py, pz.

[ C e l l ] 100 1 -1.0 -999 #102 #103 #104 #105 #106 101 -1 999 102 1 -1.0 -11 12 #106 103 1 -1.0 -12 11 #106 104 1 -1.0 -11 -12 #106 105 1 -1.0 -101 -301 #106 106 1 -1.0 111 -112 -201



Contents 48

Table of Contents


SimpleGEO

49SimpleGEO

• GUI interface to make geometry of many Monte Carlo codes• A free software developed in CERN (registration required*)

http://theis.web.cern.ch/theis/simplegeo/

Simple GEO + PHITS sample (utility\simplegeo)

How to use SimpleGEO

50SimpleGEO

1. Setup your geometry by placing spheres, rectangles, cylinders etc.2. Convert the geometry into PHITS input format (only [cell] and [surface]

sections), using macro bodies3. Copy the output geometry and paste into PHITS input file4. Execute PHITS5. Import the tally output file into SimpleGEO, and draw the results

combined with 3D geometry

Examples of SimpleGEO + PHITS results



Contents 51

Table of Contents


How to add materials

Geometry (How to add material)

52

• gold （ density: 19.32 g/cm3 ） 197Au 100

• copper （ density: 8.93 g/cm3 ）　　　 63Cu 0.6915 65Cu 0.3085

• air （ density: 1.20x10-3 g/cm3 ）　　　 14N 8 16O 2

• polyethylene （ density: 0.9 g/cm3 ）　　　 12C 2 1H 4

Add a new material number and define a composition ratio or isotopic ratio of the material in [material] section.(Density should be given in [cell] section.)

[ M a t e r i a l ]mat[1] 1H 2 16O 1mat[2] ******

・・・・・・・・・・・・[ C e l l ] 100 1 -1.0 -10 #102 #103 #104 #105 #106 101 -1 10 102 1 -1.0 -11 12 #106 103 1 -1.0 -12 11 #106 104 1 -1.0 -11 -12 #106 105 1 -1.0 -13 -14 #106 106 1 -1.0 -15 16 -17

Exercise 7


53

lec01.inp

*Each material (number) has own color.

Let’s execute PHITS and see the result.

Change the material in the cell “106”.• Set copper with an isotopic ratio of 63Cu:65Cu =

0.6915 : 0.3085 and its density to be 8.93 g/cm3

• Define the material number 2 in [material] section and the material is used in [cell] section.

[ M a t e r i a l ]mat[1] 1H 2 16O 1mat[2] 63Cu 0.6915 65Cu 0.3085

・・・・・・・・・・・・[ C e l l ] 100 1 -1.0 -10 #102 #103 #104 #105 #106 101 -1 10 102 1 -1.0 -11 12 #106 103 1 -1.0 -12 11 #106 104 1 -1.0 -11 -12 #106 105 1 -1.0 -13 -14 #106 106 2 -8.93 -15 16 -17

Answer 7


54

lec01.inp

track_xz.eps

For metal, its isotopic ratio should be given explicitly.

Change the material in the cell “106”.

How to make a void cell

55

lec01.inp

Material number for void = 0(Material number for outer region = -1)Density should not be inputted for those cells


track_xz.eps

[ C e l l ] 100 0 -10 #102 #103 #104 #105 #106 101 -1 10 102 1 -1.0 -11 12 #106 103 1 -1.0 -12 11 #106 104 1 -1.0 -11 -12 #106 105 1 -1.0 -13 -14 #106 106 2 -8.93 -15 16 -17

Confirmation of geometry（ 3D view ）

Geometry (3D plot) 56

lec01.inp

Let’s see the geometry in 3D view by using [t-3dshow] tally.

3dshow.eps

[ P a r a m e t e r s ] icntl = 11file(6) = phits.out

・・・・・・・・・・・・[ T - 3Dshow ] output = 3・・・・・・・・・・・・

Set 11when you use[t-3dshow] tally

You will learn how to use [t-3dshow] in Basic Lecture II.

Change the colors

57

You can specify the name and color of each material (number).

lec01.inp

[ M a t N a m e C o l o r ] mat name color 1 Water pastelblue 2 Copper darkred

3dshow.eps

Geometry (Change material colors)

Color definition

58

Definition in Angel

Geometry (Change material colors)



Contents 59

Table of Contents


Main components of input

Source 60

[Source]define source

• In the PHITS simulation, you have to specify the geometry of 3-dimensional virtual space and information of source particles, and then you can tally various quantities by simulating particle motions in the virtual space

　⇒ ①　 Geometry

　　　 ②　 Source

　　　 ③　 Tally

Types of sources

61

• Radio-Isotope (RI) facilities

　　　→ Point isotropic source

• Accelerator facilities

　　　→ Pencil or broad beam for certain direction

→ Cone beam source

• Radioactive waste and internal exposure

→ Volume isotropic source

• Cosmic-ray and external exposure

→ Isotropic irradiation within certain area

Source

Definition of sources

62

• Shape of source distribution　　　← select from source volume type

(point, cylindrical, spherical etc.)

• Energy of source particle　　　← mono-energy or having spectrum

• Kind of source particle　　　← neutron, photon, proton, heavy-ion

etc.

• Direction of source particle　　　← isotropic, directional, cone shape etc.

Source

Shape and energy of source

63

lec01.inp [ S o u r c e ]s-type = 1proj = protondir = 1.0r0 = 0.0z0 = 0. z1 = 0.e0 = 150

[ S o u r c e ] section : definition of sources

s-type: Define source type = 1 mono-energy, cylindrical shape

What information is required in definition of a cylinder?

Source

Definition of cylinder source

64

X,Y coordinate of center position: （ x0, y0 ）

The main direction of PHITS is z-axis.

r0: radius of cylinder

（ r1: inner radius ）

Z0: minimum Z

Z1: maximum Z

Z-axis

Source

Extension of cylinder source

65


cylinder

Z-axis

Circle

z0 = z1Example: z0 = 5.0 z1 = 5.0

Z-axis

point

z0 = z1,r0 = 0.0

Z-axis

Source

Exercise 8

Source 66

lec01-8.inp （ use this file ）


Check geometry


transportcalculation

[ S o u r c e ]s-type = 1proj = protondir = 1.0r0 = 0.z0 = 0. z1 = 0.e0 = 150

Point source at the origin (0,0,0)

Execute the transport calculation.

track_xz.eps

Answer 8

Source 67


transportcalculation


Point source at the origin (0,0,0)

Execute the transport calculation.

lec01-8.inp （ use this file ）

Exercise 9

Source 68

lec01.inp


Let’s make a circle source with a radius of 1cm.

Answer 9

Source 69

lec01.inp


track_xz.eps

The radius of the beam is 1cm.

Let’s make a circle source with a radius of 1cm.

Energy of source

70

lec01.inp [ S o u r c e ]s-type = 1proj = protondir = 1r0 = 1.0z0 = 0. z1 = 0.e0 = 150

s-type = 1　　 mono-energy, cylindrical shape

e0: energy （ MeV/u ）

s-type = 4 　 having energy spectrum, cylindrical shape

Unit in “MeV/u”

You can set any spectrum(see lecture\advanced\sourceA or Manual 4.3.15)

Source

Kind of source particle

71

lec01.inp [ S o u r c e ]s-type = 1proj = protondir = 1r0 = 1.0z0 = 0. z1 = 0.e0 = 150

proj: kind of sourcesYou can specify kind of source by ‘symbol’ or ‘kf-code’.

Source

When you use radionuclides as sources, you have to set the kind of their emitted particles, such as ‘photon’.

Exercise 10

Source 72

lec01.inp


Let’s set a neutron source of 100 MeV.

Answer 10

Source 73

lec01.inp

[ S o u r c e ]s-type = 1proj = neutrondir = 1.0r0 = 1.z0 = 0. z1 = 0.e0 = 100

Neutron can penetrate materials easily. track_xz.eps

Let’s set a neutron source of 100 MeV.

Direction of source particle(polar angle)

74


dir: direction cosine along the z-axis ※ special

dir = all isotropic source dir = -all isotropic irradiation

dir = 1

dir = cos

Z-axis

*Polar coordinate system

Source

degrees

Direction of source particle(azimuthal angle)

75


phi: angle from x-axis （ degree! ）

degrees

Z-axis

X-axis

degrees

dir = cos , phi =

*Polar coordinate system

Source

Y-axis

Spread of source beam

76

dom: solid angle （ degree! ）

dom =

degrees

Source

Source direction and parameters

77Source

Exercise 11

Source 78

lec01.inp

[ S o u r c e ]s-type = 1proj = neutrondir = 1.0r0 = 1.z0 = 0. z1 = 0.e0 = 100

Let’s set a point isotropic source at the XYZ coordinate （ 0, 0, 10 ） .

Answer 11

Source 79

lec01.inp

[ S o u r c e ]s-type = 1proj = neutrondir = allr0 = 0.z0 = 10. z1 = 10.e0 = 100

track_xz.eps

When s-type=1, you can set a isotropic source by dir=all.

Let’s set a point isotropic source at the XYZ coordinate （ 0, 0, 10 ） .



Contents 80

Table of Contents


Summary

Summary 81

• The main components of PHITS input file are “Geometry”, “Source” and “Tally”

• “Geometry” is defined by [material], [surface] and [cell] sections, and you can define various 3D shapes based on the GG concept

• “Source” is defined by shape, kind, energy and direction of source particles

• “Tally” is used for specifying what kind of quantities you have to deduced from the PHITS simulation

You will learn more about “Tally” in phits-lec02-en.ppt

Home work (Geometry)

Homework 82

• Make a cylinder with a 20 cm diameter and a 50 cm height filled with water. The outside of the cylinder is void

• Confirm the geometry

X-axis

Y-axis

Z-axis

R-axis

3D space

Start with “Phits\lecture\basic\homework\homework1.inp”

Homework (source)

83

• Set proton beam of 290 MeV/u with a 2.5 cm radius, and incident the beam to the bottom of the cylinder

• Execute the transport calculation

X-axis

Y-axis

Z-axis

R-axis

source

Homework

p hi t s

Documents

input format of phits

various information

source generation

source termyou

calculationbatch information

tallyendsample input

tally section

input filedescription