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PHITS Multi-Purpose Particle and Heavy Ion Transport code System Basic Lecture I: Geometry and Source Definition Oct. 2014 revised title 1 Purpose of This Lecture 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) Purpose 2 Table of Contents • General Description • Geometry • • • • • General definition Boolean operator How to define cell with many surfaces Macrobody and SimpleGEO How to add material • Source • Summary • Homework Contents 3 Format of PHITS input Calculation condition can be specified by text file Input file consists of several sections [ Section Name ] ←start of this section Basic format keyword（parameter） = value or character (“space” means nothing) parameter1 or parameter2 parameter3 … • Parameters are separated by “space” • You can write 200 characters in one line • Insert more than 6 spaces in successive line Parameters can be given in mathematic equations: e.g. 1.0+exp(-2.0) General description 4 Input support command *You can write sections in arbitrary order [ ]off skip this section qp: skip from this line to the next section q: equivalent to [end] section Comment 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 5 Main components of input • 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 Three fundamental ② Source components ③ Tally See sample input “lec01.inp” General description 6 Result of the sample input track_xz.eps phits.out Version Number Display of the result Summary of the calculation General description 7 phits.out Output File 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 Error information is usually given in the console Window, but occasionally in the output file! General description 8 Sample input [Title] lec01.inp title comments [Parameters] define parameters [Source] define source [Material] define materials [Surface] define surfaces [Cell] define cells [T-Track] track length tally [End] This consists of 8 sections. ② Source Production of particles ① Geometry Definition of 3D virtual space ③ Tally Observation of quantities General description 9 List of “section” General description 10 List of tally ※ You can set several tallies at once to obtain various information on the particle transport. General description 11 Table of Contents • General Description • Geometry • • • • • General definition Boolean operator How to define cell with many surfaces Macrobody and SimpleGEO How to add material • Source • Summary • Homework Contents 12 3D virtual space in PHITS lec01.inp [Material] mat[1] 1H 2 16O 1 [Surface] 10 so 10. [Cell] 100 1 -1.0 101 -1 This part usually takes the longest time to make an input file -10 10 • 3D virtual space consists of a number of cells defined in the XYZ coordinate space • You can use infinite space. But, you have to fill them with certain material (, or define them as void). Geometry (General definition) 13 How to setup geometry You can setup 3D virtual space using GG (General Geometry) or CG(Combinational Geometry) concepts, but only GG concept will be described in this tutorial ! lec01.inp [Material] mat[1] 1H 2 16O 1 [Surface] 10 so 10. [Cell] 100 1 -1.0 101 -1 -10 10 Three steps to make geometry 1） define material [Material] section 2） define surface [Surface] section 3） define cell [Cell] section Geometry (General definition) 14 Define material Material number, (Atom & density)… lec01.inp [Material] mat[1] 1H 2 16O 1 [Surface] 10 so 10. [Cell] 100 1 -1.0 101 -1 1H : 16O = 2 : 1 ⇒ H2O（water） -10 10 Several ways to express 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) Geometry (General definition) 15 Define surface •Surface number, Shape, Parameters •Parameters are expressed in the unit of “cm” lec01.inp [Material] mat[1] 1H 2 16O 1 [Surface] 10 so 10. [Cell] 100 1 -1. 101 -1 10 -10 surface of sphere (so) having its center at the origin of the XYZ coordinate system with radius of 10 cm Various types of surfaces can be used in PHITS • s, so (Sphere) • px, py, pz (plane) • cx, cy, cz (cylinder) •rpp (rectangular) etc. (see Manual 4.8) Geometry (General definition) 16 Define cell Cell number, material number, density, surface numbers lec01.inp [Material] mat[1] 1H 2 16O 1 [Surface] 10 so 10. [Cell] 100 1 -1.0 101 -1 -10 10 100: Cell number 1 : 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 Geometry (General definition) 17 Confirmation of your geometry lec01.inp [Parameters] icntl = 8 file(6) = phits.out Set 8 when you confirm the geometry Procedure for confirming your geometry 1. Change “icntl” parameter in the [Parameters] section. 2. Execute PHITS 3. See an eps file“track_xz.eps” track_xz.eps Geometry (General definition) 18 Exercise 1 Change the radius of the surface to 20 cm. lec01.inp [Material] mat[1] 1H 2 16O 1 [Surface] 10 so 10. [Cell] 100 1 -1.0 101 -1 -10 10 Geometry (General definition) 19 Answers 1 Change the radius of the surface to 20 cm. lec01.inp [Material] mat[1] 1H 2 16O 1 [Surface] 10 so 20. [Cell] 100 1 -1.0 101 -1 -10 10 track_xz.eps Is the radius of the sphere 20 cm? Geometry (General definition) 20 Definition of a new surface • 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. lec01.inp [Material] mat[1] 1H 2 16O 1 [Surface] 10 so 20. 11 so 5. [Cell] 100 1 -1.0 101 -1 -10 10 Geometry (General definition) 21 Exercise 2 Add spherical water cell with 5 cm radius to the system. • “100” in the 1st line of [Cell] section is “cell number”. Let’s use “102” for new cell number. lec01.inp [Material] mat[1] 1H 2 16O 1 [Surface] 10 so 20. 11 so 5. [Cell] 100 1 -1.0 -10 101 -1 10 102 *** *** *** Geometry (General definition) 22 Answer 2 Add spherical water cell with 5 cm radius to the system. lec01.inp [Material] mat[1] 1H 2 16O 1 [Surface] 10 so 20. 11 so 5. [Cell] 100 1 -1.0 101 -1 102 1 -1.0 -10 10 -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: xz_track_all.err) track_xz.eps Overlapped region is painted in black. Geometry (General definition) 23 Geometry error (undefined region) 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 (General definition) 24 Table of Contents • General Description • Geometry • • • • • General definition Boolean operator How to define cell with many surfaces Macrobody and SimpleGEO How to add material • Source • Summary • Homework Contents 25 Cell definition using Boolean operators Cell can be defined by surfaces and cells using Boolean operators example A（+11） A(-11) Geometry (Boolean Operator) 26 Boolean operator （AND） Cells are basically defined using AND (“blank”). lec01.inp Add ‘+11’ to the definition of the cell 100. (+ can be omissible.) [Material] mat[1] 1H 2 16O 1 [Surface] 10 so 20. 11 so 5. [Cell] 100 1 -1.0 101 -1 102 1 -1.0 -10 11 10 -11 Inside of “10”and outside of “11” track_xz.eps True answer of the 2nd exercise. Geometry (Boolean Operator) 27 Boolean operator （NOT） You can use NOT (“#”) to exclude a region. lec01.inp equivalent [Cell] 100 1 -1.0 101 -1 102 1 -1.0 -10 11 10 -11 Rewrite another representation using #. [Cell] 100 1 -1.0 101 -1 102 1 -1.0 -10 #102 10 -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 #. Geometry (Boolean Operator) 28 Extension of virtual space 3D virtual space should be wide enough to describe particle transport. Change 20cm to 500cm. lec01.inp [Material] mat[1] 1H 2 16O 1 [Surface] 10 so 500. 11 so 5. [Cell] 100 1 -1.0 101 -1 102 1 -1.0 -10 #102 10 -11 track_xz.eps Geometry (Boolean Operator) 29 Exercise 3 Where is cell “103” in the right panel? lec01-3.inp（use this file） [Material] mat[1] 1H 2 16O 1 [Surface] 10 so 500. 11 so 5. 12 sz 11. 5. [Cell] 100 1 -1.0 101 -1 102 1 -1.0 103 1 -1.0 -10 #102 #103 10 -11 -12 sphere having its center in the XYZ coordinate (0, 0, 11) with radius of 5 cm track_xz.eps Geometry (Boolean Operator) 30 Answer 3 Where is cell “103” in the right panel? lec01.inp [Material] mat[1] 1H 2 16O 1 [Surface] 10 so 500. 11 so 5. 12 sz 11. 5. [Cell] 100 1 -1.0 101 -1 102 1 -1.0 103 1 -1.0 -10 #102 #103 10 -11 -12 sx, sy, sz can be used. Universal expression s is used with the XYZ coordinate of its center and its radius. track_xz.eps Geometry (Boolean Operator) 31 Exercise 4 Correct a geometry error. lec01.inp [Surface] 10 so 500. 11 so 5. 12 sz 8. 5. [Cell] 100 1 -1.0 101 -1 102 1 -1.0 103 1 -1.0 Change the center of this sphere -10 #102 #103 10 -11 -12 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 Expected result track_xz.eps Geometry (Boolean Operator) 32 Answer 4 Correct a geometry error. lec01.inp [Surface] 10 so 500. 11 so 5. 12 sz 8. 5. [Cell] 100 1 -1.0 101 -1 102 1 -1.0 103 1 -1.0 104 1 -1.0 -10 10 -11 -12 -11 #102 #103 #104 12 11 -12 An example of answers track_xz.eps Geometry (Boolean Operator) 33 Boolean operator （OR） lec01.inp [Cell] 100 1 -1.0 101 -1 102 1 -1.0 103 1 -1.0 104 1 -1.0 [Cell] 100 1 -1.0 101 -1 102 1 -1.0 103 1 -1.0 104 1 -1.0 -10 10 -11 -12 -11 #102 #103 #104 12 11 -12 equivalent -10 10 -11 -12 -11 #(-11 : -12) 12 11 -12 Boolean operator “OR” is expressed by “:”. NOT(#) is easier to use, but it costs more memories in PC It is better to express cells using “AND” and “OR” operators Geometry (Boolean Operator) 34 Onion geometry onion.inp [Material] mat[1] 1H 2 16O 1 [Material] mat[1] 1H 2 16O 1 [Surface] 11 so 5. 12 so 10. 13 so 15. 14 so 20. 15 so 25. [Surface] 11 so 5. 12 so 10. 13 so 15. 14 so 20. 15 so 25. [Cell] 101 1 -1. 102 1 -1. 103 1 -1. 104 1 -1. 105 1 -1. 106 1 -1. [Cell] 101 1 -1. 102 1 -1. 103 1 -1. 104 1 -1. 105 1 -1. 106 1 -1. -11 -12 #101 -13 #101 #102 -14 #101 #102 #103 -15 #101 #102 #103 #104 15 11 12 13 14 15 -11 -12 -13 -14 -15 A bad example of PHITS input file using unnecessary “#”s → Become time consuming! Geometry (Boolean Operator) 35 Table of Contents • General Description • Geometry • • • • • General definition Boolean operator How to define cell with many surfaces Macrobody and SimpleGEO How to add material • Source • Summary • Homework Contents 36 How to make a box A box can be defined using 6 planes Geometry (cell with many surfaces) 37 Definition of 6 surfaces of cube lec01.inp [Surface] 10 so 500. 11 so 5. 12 sz 8. 5. 13 px -5. 14 px 5. 15 py -5. 16 py 5. 17 pz -16. 18 pz -6. ｐｘ：Perpendicular plane to X-axis y 5 x z ｐｘ 5.0 Geometry (cell with many surfaces) 38 Exercise 5 Let’s define a rectangular. lec01.inp [Surface] 10 so 500. 11 so 5. 12 sz 8. 5. 13 px -5. 14 px 5. 15 py -5. 16 py 5. 17 pz -16. 18 pz -6. [Cell] 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 15 -16 17 -18 ＋side －side To distinguish between two regions divided by a plane, symbols “+” or “-” are used. X=x0 X axis Let’s execute PHITS and see the result to confirm whether a cube is correctly defined or not. Geometry (cell with many surfaces) 39 Answer 5 Let’s define a rectangular. lec01.inp [Surface] 10 so 500. 11 so 5. 12 sz 8. 5. 13 px -5. 14 px 5. 15 py -5. 16 py 5. 17 pz -16. 18 pz -6. [Cell] 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 15 -16 17 -18 track_xz.eps Geometry (cell with many surfaces) 40 How to make a cylinder A cylinder can be defined using an infinite cylindrical tube and two planes Geometry (cell with many surfaces) 41 Exercise 6 Let’s define a cylinder. lec01.inp [Surface] 10 so 500. 11 so 5. 12 sz 8. 5. 13 px -5. 14 px 5. 15 py -5. 16 py 5. 17 pz -16. 18 pz -6. 19 cz 1. 20 pz -19. 21 pz 19. [Cell] 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 15 -16 17 -18 #106 106 1 -1.0 -19 20 -21 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 (cell with many surfaces) 42 Answer 6 Let’s define a cylinder. lec01.inp [Surface] 10 so 500. 11 so 5. 12 sz 8. 5. 13 px -5. 14 px 5. 15 py -5. 16 py 5. 17 pz -16. 18 pz -6. 19 cz 1. 20 pz -19. 21 pz 19. [Cell] 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 15 -16 17 -18 #106 106 1 -1.0 -19 20 -21 track_xz.eps Geometry (cell with many surfaces) 43 Table of Contents • General Description • Geometry • • • • • General definition Boolean operator How to define cell with many surfaces Macrobody and SimpleGEO How to add material • Source • Homework • Summary Contents 44 Macro body How to make boxes zmax Z Y X xmin zmin xmax ymin ymax How to make cylinders Radius: r Vector from (vx vy vz) to center coordinate of top face: (hx hy hz) [Surface] ・ ・ ・ 22 rpp xmin xmax ymin ymax zmin zmax [Surface] ・ ・ ・ 23 rcc vx vy vz hx hy hz r Center coordinate of bottom face: (vx vy vz) Macrobody and SimpleGEO 45 Exercise 7 Let’s define the rectangular by using macro-body. lec01.inp [Surface] 10 so 500. 11 so 5. 12 sz 8. 5. $ 13 px -5. $ 14 px 5. $ 15 py -5. $ 16 py 5. $ 17 pz -16. $ 18 pz -6. 19 cz 1. 20 pz -19. 21 pz 19. 22 rpp -5. 5. -5. 5. -16. -6. [Cell] 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 -22 #106 106 1 -1.0 -19 20 -21 The inside and outside correspond to “-” and “+” symbols, respectively. Let’s confirm the same result as the previous one. Geometry (cell with many surfaces) 46 Answer 7 Let’s define the rectangular by using macro-body. lec01.inp [Surface] 10 so 500. 11 so 5. 12 sz 8. 5. $ 13 px -5. $ 14 px 5. $ 15 py -5. $ 16 py 5. $ 17 pz -16. $ 18 pz -6. 19 cz 1. 20 pz -19. 21 pz 19. 22 rpp -5. 5. -5. 5. -16. -6. [Cell] 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 -22 #106 106 1 -1.0 -19 20 -21 track_xz.eps Geometry (cell with many surfaces) 47 SimpleGEO • GUI interface to make geometry of many Monte Carlo codes • A free software developed in CERN (registration required*) Simple GEO + Recommendation setting of PHITS (\simplegeo) http://theis.web.cern.ch/theis/simplegeo/ Macrobody and SimpleGEO 48 How to use SimpleGEO 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 bodies 3. Copy the output geometry and paste into PHITS input file 4. Execute PHITS 5. Import the tally output file into SimpleGEO, and draw the results combined with 3D geometry Examples of SimpleGEO + PHITS results Macrobody and SimpleGEO 49 Table of Contents • General Description • Geometry • • • • • General definition Boolean operator How to define cell with many surfaces Macrobody and SimpleGEO How to add material • Source • Summary • Homework Contents 50 How to add materials 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.) • 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 Geometry (How to add material) 51 Exercise 8 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. lec01.inp [Material] mat[1] 1H 2 16O 1 mat[2] ****** ・・・ ・・・ ・・・ ・・・ [Cell] 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 -22 #106 106 1 -1.0 -19 20 -21 *Each material (number) has own color. Let’s execute PHITS and see the result. Geometry (How to add material) 52 Answer 8 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. lec01.inp [Material] mat[1] 1H 2 16O 1 mat[2] 63Cu 0.6915 65Cu 0.3085 ・・・ ・・・ ・・・ ・・・ For metal, its isotopic ratio [Cell] should be given explicitly. 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 -22 #106 106 2 -8.93 -19 20 -21 track_xz.eps Geometry (How to add material) 53 Change the colors lec01.inp [Mat mat 1 2 Name Color] name color Water pastelblue Copper darkred You can specify the name and color of each material (number). track_xz.eps Geometry (How to add material) 54 Color definition by Angel Geometry (How to add material) 55 How to make a void cell lec01.inp [Cell] 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 -22 #106 106 2 -8.93 -19 20 -21 Material number for void = 0 track_xz.eps (Material number for outer region = -1) Density should not be inputted for those cells Geometry (How to add material) 56 Table of Contents • General Description • Geometry • • • • • General definition Boolean operator How to define cell with many surfaces Macrobody and SimpleGEO How to add material • Source • Summary • Homework Contents 57 Main components of input • 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 [Source] ② Source define source ③ Tally Source 58 Types of sources • 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 59 Definition of sources • 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 60 Shape and energy of source lec01.inp [Sou s-type proj dir r0 z0 z1 e0 rce] =1 = proton = 1.0 = 0.0 = 0. = 0. = 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 61 Definition of cylinder source The main direction of PHITS is z-axis. Z-axis r0: radius of cylinder Z1: maximum Z （r1: inner radius） X,Y coordinate of center position: （x0, y0） Z0: minimum Z Source 62 Extension of cylinder source Z-axis The main direction of PHITS is z-axis. Z-axis Z-axis z0 = z1 Example: z0 = 5.0 z1 = 5.0 cylinder Circle Source z0 = z1, r0 = 0.0 point 63 Exercise 9 Execute the transport calculation. lec01-9.inp（use this file） [Parameters] icntl = 8 0 file(6) = phits.out [Sou s-type proj dir r0 z0 z1 e0 rce] =1 = proton = 1.0 = 0. = 0. = 0. = 150 Check transport geometry calculation Point source at the origin (0,0,0) Source 64 Answer 9 Execute the transport calculation. lec01-9.inp（use this file） [Parameters] icntl = 0 file(6) = phits.out [Sou s-type proj dir r0 z0 z1 e0 rce] =1 = proton = 1.0 = 0. = 0. = 0. = 150 transport calculation Point source at the origin (0,0,0) track_xz.eps Source 65 Exercise 10 Let’s make a circle source with a radius of 1cm. lec01.inp [Sou s-type proj dir r0 z0 z1 e0 rce] =1 = proton = 1.0 = 0. = 0. = 0. = 150 Source 66 Answer 10 Let’s make a circle source with a radius of 1cm. lec01.inp [Sou s-type proj dir r0 z0 z1 e0 rce] =1 = proton = 1.0 = 1. = 0. = 0. = 150 The radius of the beam is 1cm. track_xz.eps Source 67 Energy of source lec01.inp [Sou s-type proj dir r0 z0 z1 e0 rce] =1 = proton =1 = 1.0 = 0. = 0. = 150 s-type = 1 mono-energy, cylindrical shape Unit in “MeV/u” e0: energy （MeV/u） s-type = 4 having energy spectrum, cylindrical shape You can set any spectrum (see Manual 4.3.15) Source 68 Kind of source particle lec01.inp [Sou s-type proj dir r0 z0 z1 e0 rce] =1 = proton =1 = 1.0 = 0. = 0. = 150 proj: kind of sources You can specify kind of source by ‘symbol’ or ‘kf-code’. When you use radionuclides as sources, you have to set the kind of their emitted particles, such as ‘photon’. Source 69 Exercise 11 Let’s set a neutron source of 100 MeV. lec01.inp [Sou s-type proj dir r0 z0 z1 e0 rce] =1 = proton = 1.0 = 1. = 0. = 0. = 150 Source 70 Answer 11 Let’s set a neutron source of 100 MeV. lec01.inp [Sou s-type proj dir r0 z0 z1 e0 rce] =1 = neutron = 1.0 = 1. = 0. = 0. = 100 Neutron can penetrate materials easily. track_xz.eps Source 71 Direction of source particle (polar angle) The main direction of PHITS is z-axis. Z-axis dir = 1 q degrees dir: direction cosine along the z-axis ※ special dir = all isotropic source dir = -all isotropic irradiation dir = cos q *Polar coordinate system Source 72 Direction of source particle (azimuthal angle) The main direction of PHITS is z-axis. Z-axis phi: angle from x-axis（degree!） q degrees dir = cos q, phi = f f degrees X-axis *Polar coordinate system Source 73 Spread of source beam dom: solid angle（degree!） dom = d d degrees Source 74 Source direction and parameters Source 75 Exercise 12 Let’s set a point isotropic source at the XYZ coordinate （0, 0, 10）. lec01.inp [Sou s-type proj dir r0 z0 z1 e0 rce] =1 = neutron = 1.0 = 1. = 0. = 0. = 100 Source 76 Answer 12 Let’s set a point isotropic source at the XYZ coordinate （0, 0, 10）. lec01.inp [Sou s-type proj dir r0 z0 z1 e0 rce] =1 = neutron = all = 0. = 10. = 10. = 100 When s-type=1, you can set a isotropic source by dir=all. track_xz.eps Source 77 Table of Contents • General Description • Geometry • • • • • General definition Boolean operator How to define cell with many surfaces Macrobody and SimpleGEO How to add material • Source • Summary • Homework Contents 78 Summary • 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 Summary 79 Table of Contents • General Description • Geometry • • • • • General definition Boolean operator How to define cell with many surfaces Macrobody and SimpleGEO How to add material • Source • Summary • Homework Contents 80 Home work (Geometry) • 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 3D space Y-axis R-axis X-axis Z-axis Start with “Phits\lecture\homework\homework.inp” Homework 81 Homework (source) • 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 Y-axis R-axis source X-axis Homework Z-axis 82