Download FLUKA: what`s new

FLUKA: what’s new
F.Cerutti, A.Empl, A.Fedynitch, Alfredo Ferrari,
P.R.Sala, G.Smirnov, V.Vlachoudis
for the FLUKA Collaboration
CERN Geneva, INFN Milan, DESY Zeuthen, UH Houston
Fluka hA/AA models: improvements shown today
ElectroMagneticDissociation
Reworking vs LHC data
PEANUT
2104 > E > ~0.01 GeV
DPMJET-3
108 > E > 2104 GeV
108 > E/n > 5-10 GeV
Extended rQMD
5-10 > E/n > 0.1-0.15 GeV
BME
100-150 > E/n > ~5 MeV
Revision and preeq. for complex mech.
October 11th, 2016
Alfredo Ferrari, SATIF13
Preequilibrium step
2
Outline:
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Improvements/new features related to
LHC and future high energy projects
 Phojet/Dpmjet: physics enhancements
ElectroMagneticDissociation:
 E2… in ElectroMagnetic Dissociation
 Muon and Electronuclear interactions
Fermi break-up and evaporation
 MLO model for gamma competition
Improvements related to Neutrino beams
and interactions
 (anti)neutrino cross sections
 Some final state comparisons
Fully correlated pointwise n xsec for a few
selected isotopes
 Carbon/scintillator response
September, 15th
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Gamma de-excitation
 Physics
 Applications to hadrontherapy
Medical applications
 Improved ion-ion nuclear models
 Application to TPS
 Hadrontherapy monitoring
Radiation to electronics
 Radiation monitoring for electronics
 SEE cross sections
Isotope production by light ions on heavy
elements  sea D.Kiselev talk tomorrow
Releases, if/when/maybe...
Alfredo Ferrari, ND2016
3
LHC and future projects (LHC, FCChh, FCCee)
Many data of relevance for machine/protection, shielding etc, collected in the 1st
LHC run by the experiments (ATLAS, CMS, LHCb, Alice, Totem) at 7, 8 TeV cms
 … comparison with p-p (and Pb-Pb) event generators (not surprisingly) showed
areas where improvements were required …
 … with the exception of EMD for Pb-Pb where predictions were remarkably
accurate (but the impact on the machine losses still to be fully worked out)

Improvements were critical for the new LHC runs @ 6.5+6.5 TeV where
quenching margins are much lower… LHC is successfully running at 13 TeV cms
with record luminosities
 … for HL-LHC (High Luminosity LHC upgrade) …
 … and for the (highly hypothetical!) Future Circular Collider , a 100 km ring for a
pp (50+50 TeV) and an ee (up to 175+175 GeV) colliders

October 11th, 2016
Alfredo Ferrari, SATIF13
4
Improvements to Phojet/Dpmjet*
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*PhD work of A.Fedynitch
Proc. of Varenna 2015
http://cds.cern.ch/record/2115393
For heavy ion interactions above 5 GeV/A, pp and hA above 20
TeV Fluka interfaces to DPMJET-3 (alias PHOJET)
Comparisons with s=7 TeV LHC data showed some discrepancies
Improved minijet treatment
New PHYTIA version for hadronization
Improved: parton densities
First round of improvements
(SATIF12) 
Data: The ALICE
Collaboration, Eur. Phys.
J. C 68, 345 (2010).
Then the LHC experiments published new, significantly
different at low X’s structure functions, and the work had to
start again....
October 11th, 2016
Alfredo Ferrari, SATIF13
5
… final “new” Phojet/Dpmjet vs LHC results
CMS: PLB43,751
Average
charged
particle
multiplicity
as a function
Charged
particle
multiplicity
distribution
for of
pseudo
rapidityranges
in the in
central
region as
measured
different
the forward
region
CMS @ by
s=13
TeV
(2<<4.5) asby
measured
LHCb
@ s=7 TeV
October 11th, 2016
Charged particle multiplicity distribution for
different pT ranges in the forward region
(2<<4.5) as measured by LHCb @ s=7 TeV
Alfredo Ferrari, SATIF13
6
New features in ElectroMagneticDissociation
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Already tested/applied at LHC energies
with sound results (PRSTAB17,021006)
New: general improvement of
ElectroMagnetic Dissociation (EMD), now
including the E2 multipolarity and nuclear
finite size and HO effects  important
at low energies and for  and e
EMD extended to  below the -N
threshold
EMD extended to e  electronuclear
interactions
(Deuteron Coulomb dissociation)
October 11th, 2016
Alfredo Ferrari, SATIF13
Alice data @ LHC
Curves: Fluka EMD predictions
Symbols: exp. data
7
EMD cross section: Fluka implementation

The EMD cross section can be expressed as (ni being the equivalent photon number for the ith
multipolarity already integrated over all impact parameters):
Emax
 EMD     i A E ni E 
E
i
It can be shown that the dominant components are E1 and E2, with E2 being (for ions) important
mostly at low energies, while M1 is always negligible:
Emax
dE
 EMD    E1 A E nE1 E    E2 A E nE2 E 
E
This
is the part which has been modified
(mostly for E2)
E
min
to ~match
2nd Born
and nuclear
finite size
…the equivalent (virtual) photon
number
is customarily
expressed
asnumerical
a function of the adiabacity
(next slide)
parameter , defined as (=E, b=impactcalculations
parameter):
i

 A E     i A E 
dE
Emin



2Z 2 
1 2 2 2

2








nE1 E  

K

K




K


K

0
1
1
0

 2 
2



October 11th, 2016
b


 max

max 

b min
nE 2 E  
2Z 2

4
21   K     2    K  K    12   K    K  
2
b ion
min  R AB   Ruth
Alfredo Ferrari, SATIF13
2
1
2 2
2
0
b lepton
 c 
min
1
4
2
1
2
0

 m lepton
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... new developments: e () higher order Born approx.
Many papers discuss the E1, M1 and E2 virtual photon spectra by e+/e- beyond the
1st Born approximation which is (partially) at the basis of the previous formulae
 In particular, we investigated three (old) papers/codes including both higher Born
approximations and the effect of nuclear/charge finite size. The only one which
with some mods was able to work up to the energies of interest for us, was
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Sovps (PRC27 (1983), CPC32 (1985))
which was used extensively to derive the corrections now implemented in FLUKA
 Accounting for 2nd Born and nuclear finite size results in a reduction of the E2
component larger for larger Z
 At  energies close to the electron energy, and for high energies, the uncorrected
approach is supposed to be correct (and in agreement with alternative derivations,
like EPA, see next slide)

...and all machinery has been extended to 
October 11th, 2016
Alfredo Ferrari, SATIF13
9
Comparison with Sovps (and EPA): 1 GeV e- on Au
Fluka E1
Fluka E2
EPA
Sovps E1
Sovps E2
EPA: Equivalent Photon Approximation (PhysRep15,181)
Often used to describe *
spectra by high energy
electrons
E1 = 11.3 mb
E2 = 0.8 mb
EPA= 10.3 mb
October 11th, 2016
Alfredo Ferrari, SATIF13
10
Low energy heavy ions:
In order to reproduce “low” (below few hundreds MeV/n) energy EMD data for ions the E2
contribution is important
 An example of (theoretical) calculations (Bertulani, PhysRep163) is plotted below for 40Ca
on 238U
 Some numerical examples are given below:
208Pb208Pb* @ 50 MeV/n
EMD=190 mb (E2=120 mb)
56Fe208Pb* @ 100 MeV/n
EMD=260 mb (E2=90 mb)
208Pb208Pb* @ 500 MeV/n
EMD=4100 mb (E2=750 mb)
Results are in reasonable agreement with
expectations and available exp. data (eg
E2~0.25 EMD for 238U238U @ 120 MeV/n,
LBL31704)

October 11th, 2016
Alfredo Ferrari, SATIF13
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181Ta(e-,n)180Ta:
E1+E2 (FLUKA)/EPA vs exp.
Examples of electronuclear
reaction:
181Ta(e-,n)180Ta:
 Blue symbols: data from JPG13,515
 Blue line: FLUKA E1+E2+HO
 Red symbols: FLUKA with EPA
(Equivalent Photon Approximation)
C(e-,n)11C:
 Green symbols: data from
ZPA281,35
 Green curve: FLUKA E1+E2+HO
October 11th, 2016
Alfredo Ferrari, SATIF13
12
Photofission is ~back!
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Some, otherwise important,
improvements in the FLUKA
evaporation, somewhat screwed
up photofission on actinides a
few years ago
Recent work on actinides pairing
and the impact of angular
momentum on fission barriers
fixed the issue
Example on the right for
238U(,f), symbols exp. data,
histogram FLUKA
October 11th, 2016
Alfredo Ferrari, SATIF13
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238U(e-/+,f):
E1+E2 FLUKA vs exp.
Further test of LeptoNuclear interactions:
Electro(Positro)Fission on 238U
 Blue symbols exp. data for 238U(e-,f) from
various sources (ZPA292,285; PRC14,1499;
NPA378,237), blue line FLUKA
 Red symbols exp. data (NPA378,237) for
238U(e+,f) from, red line FLUKA
October 11th, 2016
Alfredo Ferrari, SATIF13
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Cosmic muons at Gran Sasso:
Cosmic rays in the atmosphere:
cosmic rays induced showers
in the earth atmosphere can
produce  through the decay
of mesons
Experiment underground:
the most energetic muons can
reach the underground lab at
the depth of underground GS
lab corresponding to ~3800
mwe
The geometry of the mountain (as taken from
the map used in MACRO experiment) has been
described using the “voxel” system of FLUKA.
Our choice: 1 voxel = 100x100x50 m3
October 11th, 2016
Alfredo Ferrari, SATIF13
The layered geological structure
has been reproduced (5 different
materials)
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Cosmogenic backgrounds at Gran Sasso
Borexino detector:
 ~300 tons of liquid scintillator
surrounded by 1000 + 2400
tons of Sci/H2O shielding
 Primary physics goal: solar ’s
 Possibility of measuring
neutrons and radioactive
decays related to passing
cosmic muons (average energy
of ’s at Gran Sasso depth
~283 GeV)
 induced photonuclear reactions expected to
benefit from the introduction of spin/parity
considerations in Fermi break-up (see ND2013)
and from the new EMD (E1+E2) extended
below the pion threshold
Critical test of ( and ) photonuclear
interactions, as well as of  atomic
physics (dE/dx, e pair prod., bremss.)
October 11th, 2016
Alfredo Ferrari, SATIF13
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 Induced neutron multiplicity events @ Borexino*
*A.Empl et al, APCPC,1672,090001
Neutron producing  event rate
(evt/day @ inner detector)
Borexino: 671
Fluka:
621
Fluka2011: 421
October 11th, 2016
Alfredo Ferrari, SATIF13
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11C
prod yield:
(10-7/( g/cm2))
Borexino: 866115
Fluka:
767 19
Fluka2011: 467 23
October 11th, 2016
Alfredo Ferrari, SATIF13
*A.Empl private comm. & APCPC,1672,090001
 Produced radioisotopes @ Borexino*
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AA improvements at energies relevant for therapy
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As explained before an extensively improved and modified version of rQMD-2.4
(ASR34,1302, AnnPhys192,266) is used for AA interactions above 150 MeV/n
Below 100 MeV/n the BME (Boltzman Master Equation, Proc.Varenna2006,S126) model is
used, a model particularly suited for ion-ion at low energies
Between 100 and 150 MeV/n BME is progressively phased out and rQMD phased in,
both models being somewhat at the limit (upper and lower respectively) of their ranges
This energy range is of great importance for hadrontherapy applications where
FLUKA has a leading role in Europe  an effort has been made in order to
improve both models and their transition by:
 Implementing a preequilibrium stage in rQMD (using the Fluka standard
preeq. model)…
 … making rQMD aware of exact isotope-specific binding energies instead of
average ones as well as other refinements…
 … supplementing the precomputed (complete fusion) preeq. configurations
database of BME with an interface to the Fluka preeq. able to treat whichever
isotope/production mechanism combinations, + general improvements
October 11th, 2016
Alfredo Ferrari, SATIF13
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N on C @ 400 MeV/n: rQMD before and after
Neutron double
differential
spectra at various
angles
Histos: rQMD
Symbols: exp.
Data
(NSE157,142)
New
Old
October 11th, 2016
Alfredo Ferrari, SATIF13
20
C on C @ 135 MeV/n: rQMD before and after
Neutron double
differential
spectra at various
angles
Histos: rQMD
Symbols: exp.
Data
(PRC64,034607)
New
Old
October 11th, 2016
Alfredo Ferrari, SATIF13
21
C on Al @ 135 MeV/n: BME before and after
Neutron double
differential
spectra at various
angles
Histos: BME
Symbols: exp.
data
New
Old
October 11th, 2016
Alfredo Ferrari, SATIF13
22
C on C @ 135 MeV/n: rQMD/BME transition
Neutron double
differential
spectra at various
angles
Histos:
BME/rQMD
Symbols: exp. data
rQMD
BME
October 11th, 2016
Alfredo Ferrari, SATIF13
23
Ar on C @ 95 MeV/n: (mod) rQMD still ~working!
Neutron double
differential
spectra at various
angles
Histos:
BME/rQMD
Symbols: exp.
Data (PRC64,
034607)
rQMD
BME
October 11th, 2016
Alfredo Ferrari, SATIF13
24
Fully correlated (pointwise) n  and inter. En < 20 MeV
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Using pointwise cross sections and fully correlated final state products for neutrons
below 20 MeV is a long term goal of Fluka (and not only… see Phits, NIMA763, 575). The
main issue is that evaluated data files are hopelessly inclusive…
As a step along this direction, fully correlated pointwise /interactions have been
implemented for: 1H, 2H, 3He, 4He, 6Li, 10B (partially), 12/natC, 40Ar (partially)
… the goal being to start from isotopes of relevance for n detector simulations
12/natC pointwise/correlated interactions have been generated starting from ENDFB-VII.1,
adding model/exp. extra information where required for correlations, and slightly changing
some of the cross sections ((n,p), (n,)) where exp. data so suggested
Examples of computed scintillator and diamond detector pulseheight distributions are shown on the next slides
October 11th, 2016
Alfredo Ferrari, SATIF13
25
TRIUMF BC505 array expt.:
Resolution:
1
 E    0 
E MeV 
1
2
 0  0.005 MeV,  1  0.077 MeV
Subset used for the
neutron calibration
dEee

dx
(Further) reduced subset
for the MC simulation
dE
3
2
dx
dE  dE 
1  kB
 c

dx
dx


2
8.9 MeV
neutrons
from
- p   n
Signal cell
Front view
October 11th, 2016
Alfredo Ferrari, SATIF13
Bottom view
BC505 cells
7.6x7.6x6.4 cm3
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BC505 pulse height response to 8.9 MeV neutrons:
Importance of
understanding all details
of the actual setup!!
Color coding:
All particles
Protons from elastic recoils
All protons
Deuterons
Alphas
Other heavies
e+e- and photons
Exp. Data (NIMA431,446,1999)
If only the signal cell is
included in the geometry the
low energy part looks very
different!!
October 11th, 2016
Alfredo Ferrari, SATIF13
27
... and now with a diamond detector


Example below on a 500 m thick
diamond detector, for 18.91 MeV
neutrons
This is a simplified version of a
real detector. Its experimental
results for C(n,x) (including
12C(n,p )12B!) have been recently
i
presented at ND2016 by M.Pillon
12C(n,d
0)
11B
12C(n,p )11B
2
12C(n,p
1)
11B
12C(n,p )11B
0
October 11th, 2016
Alfredo Ferrari, SATIF13
12C(n,)9Be
28
...intercomparisons/benchmarking vs users
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Users feedback is important, very valuable and a critical tool in finding problems..
...too often incorrectly calculated results have been presented/published with many codes...
...examples of common mistakes/omissions when using FLUKA below:
Forgetting to switch on heavy
evap/fragm. when residuals matter
1 GeV p on 208Pb: residual mass spectrum
Forgetting to
Red: exp data
switch on
Blue: FLUKA with heavy evap/fragm.
coalescence,
Green:
FLUKA (left
w/0 heavy evap/fragm.
For “serious”
on, right off) or
intercomparisons
particularly please
at
benchmarking,
medium
low- or
involve
the authors
energies,
let them light
do!
targets
(113 MeV p,xn on
thick C)
October 11th, 2016
Alfredo Ferrari, SATIF13
29
... next release(s), some considerations



The last public release was Fluka2011.2(b,c) in March 2011
... as a consequence no new development has been publicly released since almost 6 years...
... despite a huge amount of improvements/new features have been added to the code, and
are extensively in use at CERN and within the Fluka Collaboration, particularly for

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Ion-ion interactions, photonuclear interactions, and nuclear interactions in general
11C, 13N, 15O, production by photons (and nucleons)
Gamma de-excitation (mostly for medical applications)
Electron/muon nuclear interactions
Isomer production by neutrons
Technical tools (medical etc)
...
This is a shame, and as a partial excuse I can only stress that to convince the management
(and colleagues) that model development is as (maybe more) important as applications is a
tough (impossible?) task and I getting tired to fight ...
... I eventually managed to get a new staff person, hopefully, crossing fingers, a public
release will occur sometimes in 2017
October 11th, 2016
Alfredo Ferrari, SATIF13
30
*In collaboration with CEA-Saclay
The neutron albedo from GCR’s at 400 km altitude*
October 11th, 2016
Thanks for your
attention!
Alfredo Ferrari, SATIF13
31