Features of PHITS2.88
PHITS development team, Sep. 2016

1Map of Models used in PHITS2.82
NeutronProton, Pion(other hadrons)

NucleusLow ← Energy → High

1 TeVMuone- / e+Photon

1 TeV/n

1 TeV

EGS5 EGS5
VirtualQuantum
PhotoNuclear
Molecular Photoor
orJAM/
Dynamics Nuclear
QMD
JAM/
Intra-nuclear cascade (INCL4.6) d (JQMD)
AtomicAtomic+
JQMD
++
Data
GEM
Data+t+Evaporation (GEM)
Evaporation GEM Library Library
3He(EEDL / JENDL-4.0 JENDL(GEM)
20 MeV
200 MeV
Intra-nuclear cascade (JAM)+ Evaporation
3.0 GeV (GEM)

NuclearData Library(JENDL-4.0)
10-5 eV

α

1 MeV
1 keV

10 MeV/nIonization
SPAR or ATIMA+ITS3.0 / / EPDL97
EPDL97) (~100GeV) NRF(~10GeV)
2 MeV

1 keV

1 keV

Event generator mode: all secondary particles are specified

Maximum energy is extended up to 1 TeV/n by fixing
bugs in high-energy nuclear reaction models*Switching energies can be changed in input file of PHITS

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Major Upgraded Features in v2.82
Upgrade Points from v2.88
 Implementation of function to read tetrahedral geometry
 Improvement of muon transport algorithm Implementation of nuclear resonance florescence model Extension of “sum tally”
 Implementation of function to read user defined cross section
 Revision of energy straggling calculation procedure Revision of statistical uncertainty calculation procedure using
dump source Revision of bugs in EGS5 mode
 Implementation of point estimator tally [t-point] Implementation of R-θ-Z mesh in [t-track] Implementation of function to generate triangle prism source3

Tetrahedral Geometry What’s tetrahedral geometry?
A kind of 3D polygon geometrycomposed only by tetrahedrons
 What’s the purpose of implementation?
Read complicated geometry such as
human body
Read CAD geometry via tetrahedralgeometry
 How to use? (see utility/TetraGeom)
Similar to voxel geometry
You have to prepare tetrahedral geometry
using other software such as TetGen** http://wias-berlin.de/software/tetgen/

Voxel phantom Polygon phantom(ICRP [1])(Hanyang Univ. [2])[1] ICRP Publication 110, [2] Y.S. Yeom et al. Phys. Med. Biol. 59, 3173-3185 (2014)
This implementation was performed under support of Prof. C.H. Kim’s group of Hanyang Univ4

Improvement of Muon Interaction Models
 Muon-induced nuclear reaction (ver.2.70)
 Negative muon capture reaction (ver.2.76)

Bremsstrahlung
Characteristic
Muon
P.P. X-ray

 Bremsstrahlung, pair production (ver.2.80) Virtual photon

X(µ,x)Y@190GeV

110target:OAl

Exp.

PHITS

SiCa Fe

010-110-21010

Be 14C22

Na 24Na 26Al 26Al 36Cl 53Mn

Produced radionuclide

Muon-induced nuclear reaction

2210

Vertical intensity [/cm /sr/s]

Cross section [mb]All interaction can be considered!!

NuclearReaction

Capture-3

10-4
M.F.Crouch,1987
10-5
M.Aglietta,1998
10-6
10-7
PHITS (w/o models)PHITS2.52
10-8
10-9
10-10
10PHITS(with models)PHITS2.88-11
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0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5
Depth of underground [km]Underground muon penetration

S. Abe and T. Sato J Nucl Sci Technol. (2016) doi: 10.1080/00223131.2016.1210043

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Nuclear Resonance Florescence (NRF)
What’s NRF?
Photo-nuclear X.sec

Nucleus can absorb photon with energy equivalent to its excite level, andemit gamma-ray with certain energies (a kind of photo-nuclear reaction)
・Giant Resonance・QDD etc

NRFNewOld~8Application
 Estimation of radioactivity after
food irradiation
 Detection of nuclear material

Energy (MeV)

How to use

1. Set ipnint = 2 in [parameters] section
2. Set polarization direction in [source] section (for polarized photon)
3. Set igamma = 3 if you would like to calculate isomer production
Absorption levels are mostly taken from ENSDF (http://www.nndc.bnl.gov/nudat2/)
T. Ogawa et al. J. Nucl. Sci. Technol. 53, 1766-1773 (2016)

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Point Tally [t-point]
What’s point tally?
Estimate particle fluence at a certain point (or line)
Effective when tally region is very small in comparison to whole geometry
Simulation Condition
 Simulation using only nuclear and atomic data libraries
 Only fluence of neutron and photon can be estimated Neither event-generator and EGS5 mode cannot be used
[t-point][t-track]

Neutron and photon fluence calculated by [t-point] and [t-track] for similar conditions
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Major Upgraded Features in v2.88
Upgrade Points from v2.82
 Implement Weight Window Generator function
 Develop output option for a 3D-viewer ParaView Set ATIMA for default stopping power calculation model Improve “sum tally” function
 Improve muon and pion nuclear interaction models
 Implement radioisotope source function
 Develop JAMQMD
 Implement neutron decay process
 Revise some bugs in the EGS5 algorithm

8Weight Window Generator
What can do with Weight Window Generator [t-wwg]?
 Automatically determine the effective settings of [weight window] Help users to easily perform deep penetration calculation
1st trial
No [Weight Window]

2nd trial
Using [Weight Window]

3rd trial
Revised [Weight Window][t-track]
Relative Error
Deep penetration calculation using [t-wwg] & [Weight Window](history numbers are the same for all trial)
9Output Function for ParaView
What’s ParaView (http://www.paraview.org)?
 Open-source, multiplatform data analysis and visualization application
 Capable of drawing tally outputs in 3D picture & animation
How to activate the function?
Simply add “vtkout = 1” in a tally with “mesh = xyz”

ICRP voxel phantom
visualized by ParaView

Sample picture of ParaView

See lecture¥advance¥paraview in more detail10

RI Source Function
What can do with RI source function?
 generate photon sources with energy spectra of radioisotope (RI)
decay by simply specifying the activity and name of the RIs
 consider activities from daughter nuclides by setting a decay time use nuclear decay database DECDC*
RI source Mono-energetic source (e-type = 8)(e-type = 28)[ Source ][ Source ]factor = 1.0…
e-type = 28
ni = 1152Eu 100.
norm = 0dtime = -10.0

dtime:
decay time

factor = 100.*1.6051…
e-type = 8
ne = 32
1.21782E-01 100.*2.86678E-01
1.25690E-01 100.*1.61100E-04
1.48010E-01 100.*3.73216E-04
1.73170E-01 100.*7.96740E-05…(repeated）
1.69810E+00 100.*5.90701E-05
1.76909E+00 100.*9.58546E-05

Input formats for representing 152Eu
with activity of 100 Bq

Photon flux from 152Eu*A. Endo et al., JAERI 1347 (2005); equivalent to ICRP Publication 107

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