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P HI T S Basic Lecture II: Definition of Tally Multi-Purpose Particle and Heavy Ion Transport code System title1 Oct. 2014 revised
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Purpose2 Learn how to deduce various physics quantities from the PHITS simulation Purpose of This Lecture You can obtain this kind of results at the end of this lecture Particle fluence (left) and depth-dose distribution (right) for the simulation condition for homework
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Contents of Lecture II Contents3 What is Tally? Introduction and usage of “Tally” How to use Tally for checking geometry How to use Tally for calculating physical quantities Kinds of Tally Summary
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What is Tally? What is tally?4 Tally: a record of the number or amount of something, especially one that you can keep adding to; [Oxford Advanced Learner’s Dictionary (7th edition), OXFORD.] In PHITS, the word of “Tally” used for functions to Deduce physical quantities such as flux and heat, or Depict the 2D or 3D geometry in certain area
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What is tally?5 PHITS simulates the motion of each particle using the Monte Carlo method. You can estimate their average behavior by calculating various physical quantities as flux and deposition energy in a certain region, using “Tally” Result of [t-track] (Track-length tally) How many particles were passed through this region? → Use “track-length” tally Concept of Tally
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Kinds of Tally in PHITS6 Calculating physical quantity –Particle flux → [t-track], [t-cross] –Heat and deposition energy → [t-heat], [t-deposit] –Secondary particles → [t-yield], [t-product] –LET or microdosimetric distribution → [t-let], [t-sed] Checking geometry –2-dimensional visualization → [t-gshow], [t-rshow] –3-dimensional visualization → [t-3dshow] Tally Types Various tally functions are implemented in PHITS Many physical quantities can be deduced from the PHITS simulation by selecting appropriate tally For example…
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Visualize Particle Trajectory method of track detection7 x-axis z-axis
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method of track detection8 x-axis z-axis Visualize Particle Trajectory
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method of track detection9 x-axis z-axis Visualize Particle Trajectory
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method of track detection10 x-axis z-axis Visualize Particle Trajectory
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method of track detection11 x-axis z-axis Visualize Particle Trajectory
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Contents of Lecture II Contents12 What is Tally? Introduction and usage of “Tally” How to use Tally for checking geometry How to use Tally for calculating physical quantities Kinds of Tally Summary
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Geometry Check Tally for checking geometry13 Every time you construct new geometry, it is better to check the geometry using [t-3dshow] or [t-gshow] Otherwise you would obtain wrong results without noticing miss-definition of the geometry, especially when you make an overlapping region!
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Exercise 1 14 Confirm the geometry of lec02.inp in 2 dimensions using [t-gshow] tally. Tally for checking geometry [ 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 cz 10. 12 pz 0. 13 pz 50. [ C e l l ] 100 -1 10 101 1 -1. -11 12 -13 110 0 -10 #101 A water cylinder with a radius of 10 cm and a height of 50 cm. lec02.inp 50 cm 10 cm Copy & paste 2 [t-gshow] sections from t-gshow.inp. Set icntl=7 in [parameters] section and execute PHITS.
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Answer 1 15Tally for checking geometry lec02.inp gshow_xz.eps gshow_xy.eps The height is 50cm. The radius is 10cm. [ P a r a m e t e r s ] icntl = 7 ・ ・ ・ [ T - G s h o w ] ・ ・ ・ axis = xy file = gshow_xy.out output = 6 epsout = 1 [ T - G s h o w ] ・ ・ ・ axis = xz output = 6 file = gshow_xz.out epsout = 1 Confirm the geometry of lec02.inp in 2 dimensions using [t-gshow] tally. xy-plane xz-plane
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How is this geometry shown in 3 dimensions? Exercise 2 16Tally for checking geometry gshow_xy.epsgshow_xz.eps Confirm the geometry of lec02.inp in 3 dimensions using [t-3dshow] tally. Copy & paste [t-3dshow] section from t-3dshow.inp. Set “ icntl=11” in [parameters] section and execute PHITS.
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17Tally for checking geometry lec02.inp [ P a r a m e t e r s ] icntl = 11 ・ ・ ・ [ T - 3 D s h o w ] output = 3 x0 = 0 y0 = 0 z0 = 20 e-the = 90 $ eye e-phi = 0 e-dst = 120 l-the = 90 $ light l-phi = 0 l-dst = 100 w-wdt = 50 $ window w-hgt = 50 w-dst = 30 ・ ・ ・ 3dshow.eps X Y Z ・ Answer 2 Confirm the geometry of lec02.inp in 3 dimensions using [t-3dshow] tally.
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Parameters used in [t-3dshow] 18 Origin (x0,y0,z0) (e-the,e-phi,e-dst) w-hgt (w-mnh) w-dst w-wdt (w-mnw) e-dst Picture Flame Eye Point Light source (l-the,l-phi,l-dst) w-mnw × w-mnh = #Pixel 100 × 100 (default) Polar Coordinates Polar coordinates XYZ-coordinates Tally for checking geometry
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19 lec02.inp Exercise 3 Tally for checking geometry 3dshow.eps [ T - 3 D s h o w ] output = 3 x0 = 0 y0 = 0 z0 = 20 e-the = 90 $ eye e-phi = 0 e-dst = 120 l-the = 90 $ light l-phi = 0 l-dst = 100 w-wdt = 50 $ window w-hgt = 50 w-dst = 30 heaven = y mirror = 0 line = 1 shadow = 2 resol = 1 file = 3dshow.out title = Check geometry using [T-3dshow] tally epsout = 1 [ T - 3 D s h o w ] output = 3 x0 = 0 y0 = 0 z0 = 20 e-the = 135 $ eye e-phi = 0 e-dst = 120 l-the = 90 $ light l-phi = 0 l-dst = 100 w-wdt = 50 $ window w-hgt = 50 w-dst = 30 heaven = y mirror = 0 line = 1 shadow = 2 resol = 1 file = 3dshow.out title = Check geometry using [T-3dshow] tally epsout = 1 X Y Z ・ X Y Z [ T - 3 D s h o w ] output = 3 x0 = 0 y0 = 0 z0 = 20 e-the = 135 $ eye e-phi = 45 e-dst = 120 l-the = 90 $ light l-phi = 0 l-dst = 100 w-wdt = 50 $ window w-hgt = 50 w-dst = 30 heaven = y mirror = 0 line = 1 shadow = 2 resol = 1 file = 3dshow.out title = Check geometry using [T-3dshow] tally epsout = 1 Rotate azimuthal angle of eye-point by 45 deg X Y Z “Heaven” is Y direction Rotate zenith angle of eye-point by 45 deg Let’s rotate the picture.
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Contents of Lecture II Contents20 What is Tally? Introduction and usage of “Tally” How to use Tally for checking geometry How to use Tally for calculating physical quantities Kinds of Tally Summary
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How to define Tally Tally for calculating physical quantities21 What kind of physical quantity Select type of tally: [t-track], [t-deposit] etc. in where Select geometrical mesh: mesh= reg, xyz, r-z of what particle Select particle type: part = neutron, proton etc. in which unit e.g. (cm/source), (1/cm 2 /source) etc. Select unit: unit = 1, 2, 3 … in what output form Select output axis: axis = eng, reg, xy, etc. You have to determine …
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22 [ T - T R A C K ] title = Track Detection in xyz mesh mesh = xyz x-type = 2 nx = 25 xmin = -25. xmax = 25. y-type = 2 ny = 25 ymin = -25. ymax = 25. z-type = 1 nz = 1 -5.0 5.0 e-type = 1 ne = 1 0.0 5000.0 unit = 1 axis = xy file = track_xy.out part = all gshow = 1 epsout = 1 Tally for calculating physical quantities Example of [t-track] tally (in t-track.inp). Geometrica l mesh Particle type Unit of output Output form [T-track]: Tally for calculating track-length or flux of particles in certain regions [T-track] can be used for visualizing particle trajectories by setting small mesh for tallying region
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Exercise 4 23 Confirm particle fluence using [t-track] tally. How is the behavior of the particles? [ S o u r c e ] s-type = 1 proj = 12C dir = 1.0 r0 = 2.5 z0 = -10. z1 = -10. e0 = 250. lec02.inp A carbon beam of 250MeV/u Tally for calculating physical quantities Copy & paste 2 [t-track] sections from t-track.inp. Set “ icntl=0” in [parameters] section and execute PHITS.
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24 lec02.inp Tally for calculating physical quantities Answer 4 [ P a r a m e t e r s ] icntl = 0 ・ ・ ・ [ T - T r a c k ] ・ ・ ・ axis = xy file = track_xy.out part = all gshow = 1 epsout = 1 [ T - T r a c k ] ・ ・ ・ axis = xz file = track_xz.out part = all gshow = 1 epsout = 1 Output file Making an eps file using name specified by “file=”. (***.out → ***.eps) In the case of 2D-plot, error files (_err.eps) are made. Confirm particle fluence using [t-track] tally.
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25 lec02.inp Tally for calculating physical quantities [ P a r a m e t e r s ] icntl = 0 ・ ・ ・ [ T - T r a c k ] ・ ・ ・ axis = xy file = track_xy.out part = all gshow = 1 epsout = 1 [ T - T r a c k ] ・ ・ ・ axis = xz file = track_xz.out part = all gshow = 1 epsout = 1 track_xz.eps track_xy.eps A carbon beam of 250MeV/u with a radius of 2.5cm Answer 4 Confirm particle fluence using [t-track] tally.
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26 track_xy_err.eps track_xz_err.eps Tally for calculating physical quantities Error file (*_err.eps) In the case of 2D-plot such as tallies with “ axis=xy, rz”, errors are output in another file named *_err.eps. Warm colors indicate that relative standard errors are large (close to 1), while cold colors mean small erros.
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How to define Tally 27 What kind of physical quantity Select type of tally: [t-track], [t-deposit] etc. in where Select geometrical mesh: mesh= reg, xyz, r-z of what particle Select particle type: part = neutron, proton etc. in which unit e.g. (cm/source), (1/cm 2 /source) etc. Select unit: unit = 1, 2, 3 … in what output form Select output axis: axis = eng, reg, xy, etc. You have to determine … Tally for calculating physical quantities
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[ T - T R A C K ] ・ ・ ・ mesh = xyz x-type = 2 nx = 25 xmin = -25. xmax = 25. y-type = 2 ny = 25 ymin = -25. ymax = 25. z-type = 1 nz = 1 -5.0 5.0 e-type = 1 ne = 1 0.0 5000.0 unit = 1 axis = xy file = track_xy.out part = all gshow = 1 epsout = 1 28 lec02.inp Tally for calculating physical quantities Geometrical Mesh mesh = xyz :Define tally region according to xyz coordinates ⇒ You need to specify x-type, y-type, z-type X-axis (x-type = 2) : xmin (minimum value) : xmax (maximum value) : nx (number of mesh) Z-axis (z-type = 1) : nz (number of mesh) : -5.0 5.0 (Boundaries, nz+1 )
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29 e-type = 1 ne = 10 0 1 2 3 5 10 15 20 30 50 100 Replace “e” to “x” if you want to define x-mesh e-type = 2 ne = 100 emin = 0 emax = 1000 1: Define #mesh and their boundaries 2,3: Define #mesh and their minimum & maximum values (2: linear, 3: logarithmic interval) e-type = 3 ne = 100 emin = 0.1 emax = 5000 e-type = 4 edel = 100 emin = 0 emax = 5000 e-type = 5 edel = 1.301 emin = 0.1 emax = 5000 =log 10 (20) How to Define Mesh Mesh is a common concept used in many tallies x-type, y-type, z-type, r-type, e-type, t-type, a-type etc. x-axis y-axis z-axis radius energy time angle You can define each mesh using the following 5 types 4,5: Define interval of mesh and their minimum & maximum values (4: linear, 5: logarithmic interval) Tally for calculating physical quantities
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30 xyz mesh: Divide the regions in XYZ coordinates X Y Z Z R Geometrical Mesh Types There are 3 types of geometrical mesh in PHITS r-z mesh: Divide the regions in Cylindrical coordinates reg mesh: Divide the regions in cells defined in PHITS virtual space Tally for calculating physical quantities
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Exercise 5 31 In order to look the figures more clearly, increase the number of mesh in the [t-track] tally. Multiply nx and ny in the [t-track] section with “axis=xy” by four. Multiply nx and nz in the [t-track] section with “axis=xz” by four. Tally for calculating physical quantities track_xz.eps track_xy.eps A higher resolution is needed.
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32Tally for calculating physical quantities [ T - T R A C K ] ・ ・ ・ mesh = xyz x-type = 2 nx = 100 xmin = -25. xmax = 25. y-type = 2 ny = 100 ymin = -25. ymax = 25. z-type = 1 nz = 1 -5.0 5.0 ・ ・ ・ axis = xy file = track_xy.out part = all gshow = 1 epsout = 1 lec02.inp track_xy.eps We can look the figure with good resolution by increase nx and ny. Answer 5 In order to look the figures more clearly, increase the number of mesh in the [t-track] tally.
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33Tally for calculating physical quantities [ T - T R A C K ] ・ ・ ・ mesh = xyz x-type = 2 nx = 100 xmin = -25. xmax = 25. y-type = 1 ny = 1 -5.0 5.0 z-type = 2 nz = 200 zmin = -20. zmax = 80. ・ ・ ・ axis = xz file = track_xz.out part = all gshow = 1 epsout = 1 lec02.inp track_xz.eps Answer 5 In order to look the figures more clearly, increase the number of mesh in the [t-track] tally.
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How to define Tally 34 What kind of physical quantity Select type of tally: [t-track], [t-deposit] etc. in where Select geometrical mesh: mesh= reg, xyz, r-z of what particle Select particle type: part = neutron, proton etc. in which unit e.g. (cm/source), (1/cm 2 /source) etc. Select unit: unit = 1, 2, 3 … in what output form Select output axis: axis = eng, reg, xy, etc. You have to determine … Tally for calculating physical quantities
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Exercise 6 35 Show the fluence of each particle separately. Replace “part=all” in the [t-track] tally with “axis=xz” by “part=12C proton neutron”. Tally for calculating physical quantities [ T - T R A C K ] ・ ・ ・ axis = xz file = track_xz.out part = all gshow = 1 epsout = 1 lec02.inp track_xz.eps How are the behaviors of 12 C, proton, and neutron?
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36Tally for calculating physical quantities [ T - T R A C K ] ・ ・ ・ axis = xz file = track_xz.out part = 12C proton neutron gshow = 1 epsout = 1 lec02.inp 12C proton neutron track_xz.eps Answer 6 Show the fluence of each particle separately.
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How to define Tally 37 What kind of physical quantity Select type of tally: [t-track], [t-deposit] etc. in where Select geometrical mesh: mesh= reg, xyz, r-z of what particle Select particle type: part = neutron, proton etc. in which unit e.g. (cm/source), (1/cm 2 /source) etc. Select unit: unit = 1, 2, 3 … in what output form Select output axis: axis = eng, reg, xy, etc. You have to determine … Tally for calculating physical quantities
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[ T - T R A C K ] ・ ・ ・ x-type = 2 nx = 100 xmin = -25. xmax = 25. y-type = 1 ny = 1 -5.0 5.0 z-type = 2 nz = 200 zmin = -20. zmax = 80. e-type = 1 ne = 1 0.0 5000.0 unit = 1 axis = xz file = track_xz.out ・ ・ ・ lec02.inp Exercise 7 38 Show the particle fluence as a function of its energy. Replace “axis=xz” by “axis=eng”. Set “e-type=2” and set ne, emin, and emax to be 100, 0, and 5000, respectively. (See “ How to Define Mesh” in 29 page.) Set “nx=1” and “nz=1” to reduce the number of pages of output. Change the output file name to “track_eng.out”. Tally for calculating physical quantities
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[ T - T R A C K ] ・ ・ ・ x-type = 2 nx = 1 xmin = -25. xmax = 25. y-type = 1 ny = 1 -5.0 5.0 z-type = 2 nz = 1 zmin = -20. zmax = 80. e-type = 2 ne = 100 $ 0.0 5000.0 emin = 0.0 emax = 5000.0 unit = 1 axis = eng file = track_eng.out ・ ・ ・ ・ ・ 39Tally for calculating physical quantities lec02.inp track_eng.eps Energy distribution of each particle The beam energy is 250×12=3000Me V Answer 7 Show the particle fluence as a function of its energy. in “MeV” (not MeV/n)
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lec02.inp Exercise 8 40 Change the horizontal axis to Logarithmic scale. Set “e-type=3” and “emin=1.0”. Tally for calculating physical quantities [ T - T R A C K ] ・ ・ ・ e-type = 2 ne = 100 $ 0.0 5000.0 emin = 0.0 emax = 5000.0 unit = 1 axis = eng file = track_eng.out ・ ・ ・ ・ ・ track_eng.eps This figure is shown in linear scale.
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lec02.inp 41Tally for calculating physical quantities [ T - T R A C K ] ・ ・ ・ e-type = 3 ne = 100 $ 0.0 5000.0 emin = 1.0 emax = 5000.0 unit = 1 axis = eng file = track_eng.out ・ ・ ・ ・ ・ track_eng.eps We can confirm the low energy region in detail. Answer 8 Change the horizontal axis to Logarithmic scale.
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[ T - T R A C K ] mesh = xyz Add “reg parameter” x-type = 2 nx = 1 xmin = -25. xmax = 25. y-type = 1 ny = 1 -5.0 5.0 z-type = 2 nz = 1 zmin = -20. zmax = 80. delete ・ ・ ・ lec02.inp Exercise 9 42 Show the energy distributions on the inside and outside of the cylinder. Change to region mesh ( mesh = reg ) Specify the two regions to tally; 101(inside) and 110(outside) Delete or comment out parameters for mesh = xyz Tally for calculating physical quantities
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[ T - T R A C K ] mesh = reg reg = 101 110 $ x-type = 2 $ nx = 1 $ xmin = -25. $ xmax = 25. $ y-type = 1 $ ny = 1 $ -5.0 5.0 $ z-type = 2 $ nz = 1 $ zmin = -20. $ zmax = 80. ・ ・ ・ lec02.inp Answer 9 43Tally for calculating physical quantities In water outside Show the energy distributions on the inside and outside of the cylinder.
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Exercise 10 44 [ T - Deposit ] title = Energy deposition in xyz mesh mesh = xyz ・ ・ ・ unit = 1 material = all output = dose axis = xz file = deposit.out part = all gshow = 1 epsout = 1 t-deposit.inp Tally for calculating physical quantities Confirm energy deposition using [t-deposit] tally. Copy & paste [t-deposit] section from t-deposit.inp. [T-deposit]: Tally for calculating deposit energy in materials
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45Tally for calculating physical quantities deposit.eps Energy deposition by the carbon beam. Energy deposition by the secondary particles. Answer 10 Confirm energy deposition using [t-deposit] tally.
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How to define Tally 46 What kind of physical quantity Select type of tally: [t-track], [t-deposit] etc. in where Select geometrical mesh: mesh= reg, xyz, r-z of what particle Select particle type: part = neutron, proton etc. in which unit e.g. (cm/source), (1/cm 2 /source) etc. Select unit: unit = 1, 2, 3 … in what output form Select output axis: axis = eng, reg, xy, etc. You have to determine … Tally for calculating physical quantities
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[ T - Deposit ] title = Energy deposition in xyz mesh mesh = xyz ・ ・ ・ unit = 1 material = all output = dose axis = xz file = deposit.out part = all gshow = 1 epsout = 1 Exercise 11 47 Change the unit of the output of the [t-deposit] tally, [MeV/cm 3 /source], to [Gy/source]. Replace “unit=1” by “unit=0”. Tally for calculating physical quantities lec02.inp It should be noted that when a region includes more than two materials, dose in the region does not equal to average value of the region. Example; E 1 /M 1 +E 2 /M 2 [PHITS] ≠ (E 1 + E 2 )/(M 1 + M 2 ) [average dose] Calculating deposit energy in the unit of Gy=J/kg.
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48Tally for calculating physical quantities deposit.eps The unit and its scale have changed. [ T - Deposit ] title = Energy deposition in xyz mesh mesh = xyz ・ ・ ・ unit = 0 material = all output = dose axis = xz file = deposit.out part = all gshow = 1 epsout = 1 lec02.inp Answer 11 Change the unit of the output of the [t-deposit] tally, [MeV/cm 3 /source], to [Gy/source].
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[ T - Deposit ] title = Energy deposition in xyz mesh mesh = xyz x-type = 2 xmin = -25.00000 xmax = 25.00000 nx = 100 y-type = 1 ny = 1 -5.0 5.0 z-type = 2 zmin = -20.00000 zmax = 80.00000 nz = 200 ・ ・ ・ axis = xz file = deposit.out ・ ・ ・ Exercise 12 49 Show z-distribution of the energy deposition in the water cylinder using r-z mesh. Replace “mesh=xyz” by “mesh=r-z” and set r-type and z-type sub-sections. Set radial range from 0 to 10 cm Replace “axis=xz” by “axis=z”. Tally for calculating physical quantities lec02.inp
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Answer 12 50Tally for calculating physical quantities lec02.inp deposit.eps A Bragg peak of the carbon beam is shown at z=12cm. Show z-distribution of the energy deposition in the water cylinder using r-z mesh. [ T - Deposit ] title = Energy deposition in xyz mesh mesh = r-z $ x-type = 2 $ xmin = -25.00000 $ xmax = 25.00000 $ nx = 100 r-type = 1 nr = 1 0.0 10.0 z-type = 2 zmin = -20.00000 zmax = 80.00000 nz = 200 ・ ・ ・ axis = z file = deposit.out ・ ・ ・
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Exercise 13 51 Using ANGEL, change the region of y-axis in deposit.eps. Add “p: ymin(1e-11) ymax(1e-9)” to the 77th line of deposit.out. Execute ANGEL. Tally for calculating physical quantities
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Answer 13 52Tally for calculating physical quantities The region between 10 -11 and 10 -9 for the vertical axis is shown. Using ANGEL, change the region of y-axis in deposit.eps. ・・・・・・ #newpage: # no. = 1 ir = 1 # r = ( 0.0000E+00 - 1.0000E+01 ) p: ymin(1e-11) ymax(1e-9) x: z [cm] y: Dose [Gy/source] p: xlin ylog afac(0.8) form(0.9) h: n x y(all ),hh0l n # z-lower z-upper dose r.err -2.0000E+01 -1.9500E+01 0.0000E+00 0.0000 ・・・・・・ deposit.out deposit.eps Setting Angel parameters, you can adjust some conditions of graphs.
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Contents of Lecture II Contents53 What is Tally? Introduction and usage of “Tally” How to use Tally for checking geometry How to use Tally for calculating physical quantities Kinds of Tally Summary
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Kinds of tally in PHITS54 Deduce physical quantity List of All Tallies in PHITS [t-track]Track length tally definition [t-cross]Surface crossing tally definition [t-heat]Heat developing tally definition [t-deposit]Deposit tally definition [t-deposit2]Deposit2 tally definition [t-yield]Residual nuclei yield tally definition [t-product]Produced particle tally definition [t-dpa]DPA tally definition [t-let]LET tally definition [t-sed]SED tally definition [t-time]Time tally definition [t-star]Star density tally definition [t-dchain]Dchain tally definition [t-userdefined]User defined tally definition [t-gshow]Region surface display definition for graphical plot [t-rshow]Physical quantity region display definition for graphical plot [t-3dshow]3D graphical geometry plot definition Visualize geometry
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[t-3dshow] Kinds of tally in PHITS55 Tally for visualizing the geometry in 3-dimension from a viewpoint of a certain location in PHITS virtual space Activated only when icntl=11 in the [parameters] section
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56 [t-3dshow](for your FUN!) Tally for checking geometry You can rotate [t-3dshow] picture using Python software See “/phits/utility/rotate3dshow” in more detail
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[t-gshow] Kinds of tally in PHITS57 Tally for visualizing the geometry in 2-dimension cut by certain slices Show region boundary, cell number, material ID etc. Other tallies can be used for this purpose by setting icntl=8 in the [parameters] section (see Lecture I)
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[t-track] Kinds of tally in PHITS58 You can visualize the trajectory of particle using [t-track] by setting small mesh for tallying regions Tally for calculating track-length (cm) of particles in certain regions Average flux (/cm 2 ) in the region can be also deduced from this tally, dividing the track length (cm) by the volume of the region (cm 3 )
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[t-cross] Kinds of tally in PHITS59 Tally for calculating flux or current (/cm 2 ) of particles crossing certain surfaces Current is simply added by 1 when a particle cross the surface, while flux is added by 1/cos( )
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[t-heat], [t-deposit] Kinds of tally in PHITS60 Tally for calculating deposition energy (MeV) in certain regions Only ionization energy losses by charged particles are scored by [t-deposit] tally → Event-by-event data can be also deduced! Neutron and photon doses are calculated by the Kerma approximation in [t-heat] tally Bragg peak calculated by [t-heat] tally
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[t-yield], [t-product] Kinds of tally in PHITS61 Tally for calculating the number of secondary particles generated by nuclear reactions in certain regions Energy or time distribution of secondary particles can be obtained from [t-product] tally Yield of each nuclide can be depicted on nuclear chart using [t-yield] tally Example of [t-yield] tally
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[t-dpa] Kinds of tally in PHITS62 Tally for calculating the radiation damage index DPA in certain regions DPA is the average number of displaced atoms per atom of a material, and is calculated from the flux multiplied with the damage cross section Depth-DPA distribution calculated using [t-dpa]
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[t-let], [t-sed] Kinds of tally in PHITS63 Tally for calculating the probability densities of deposition energy or flux in terms of LET, lineal energy (y), or specific energy (z) in microscopic sites distributed in certain regions Useful for radiobiological calculations Example of [t-let] tally *SED represents Specific Energy Distribution
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[t-deposit2] Kinds of tally in PHITS64 Tally for calculating event-by-event deposition energies in two regions Output the contour map of their correlation Useful for simulating experimental data obtained by using two detectors Example of [t-deposit2] tally
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[t-dchain] Kinds of tallies in PHITS65 Time dependence of radioactivities inside water phantom irradiated by 150 MeV proton for 6 min Tally for generating the input files for DCHAIN-SP, which can calculate the time evolution of the radioactive nuclides during and after irradiation DCHAIN-SP is also included in the PHITS package
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Contents of Lecture II Contents66 What is Tally? Introduction and usage of “Tally” How to use Tally for checking geometry How to use Tally for calculating physical quantities Kinds of Tally Summary
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67 A variety of information can be deduced from the PHITS simulation using functions called “Tally” 2 types of tallies are implemented in PHITS, one is for visualizing PHITS geometry, and the other is for calculating physical quantities Properness of the geometry can be checked by the tallies for its visualization: [t-3dshow] and [t-gshow] For defining tally, you have to determine … Summary what kind of physical quantity in where of what particle in which unit in what output form
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Homework68 Depict the neutron and proton fluences, respectively, in your homework study Adjust [t-deposit] to see the Bragg peak of proton Change the minimum & maximum values of y axis in the graph for the depth-dose distribution (use “angel” parameters) Investigate the difference of the depth-dose distributions between the inside and outside of beam center (within the radius of 2.5cm or not) by set r-z mesh Homework
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Example Answer Homework69 Proton (up) and neutron (down) fluences Depth-dose distribution inside (up) and outside (down) beam radius
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