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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 2104 > E > ~0.01 GeV DPMJET-3 108 > E > 2104 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: 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 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* *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 rapidityranges 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 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 2Z 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 2Z 2 4 21 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 8 ... 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 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: 208Pb208Pb* @ 50 MeV/n EMD=190 mb (E2=120 mb) 56Fe208Pb* @ 100 MeV/n EMD=260 mb (E2=90 mb) 208Pb208Pb* @ 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 238U238U @ 120 MeV/n, LBL31704) October 11th, 2016 Alfredo Ferrari, SATIF13 11 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! 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 13 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 14 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) 15 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 16 Induced neutron multiplicity events @ Borexino* *A.Empl et al, APCPC,1672,090001 Neutron producing event rate (evt/day @ inner detector) Borexino: 671 Fluka: 621 Fluka2011: 421 October 11th, 2016 Alfredo Ferrari, SATIF13 17 11C prod yield: (10-7/( g/cm2)) Borexino: 866115 Fluka: 767 19 Fluka2011: 467 23 October 11th, 2016 Alfredo Ferrari, SATIF13 *A.Empl private comm. & APCPC,1672,090001 Produced radioisotopes @ Borexino* 18 AA improvements at energies relevant for therapy 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 19 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 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 26 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 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 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