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INPC2007-TokyoLhuillier David - CEA Saclay - France1 Double Chooz Experiment and Applied Neutrino Physics CEA Saclay : M. Cribier, T. Lasserre, A. Letourneau, D. Lhuillier, T. Mueller SUBATECH-NANTES: S. Cormon, M. Fallot, L.Giot, B. Guillon, J. Martino, J.H. Xu http://doublechooz.in2p3.fr/ Search for 13 Simulation of e - and energy spectra Applied physics: power measurement, non-proliferation
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INPC2007-TokyoLhuillier David - CEA Saclay - France2 PHASE 1 (2009-10) - Far detector only - sin 2 (2 13 )<0.06 (1,5 years,90% C.L.) PHASE 2 (2011…) - Far + Near sites - sin 2 (2 13 )<0.025 (3 years,90% C.L.) 2 identical 8.3t targets flux Normalization @280m oscillation @1050m Double Chooz Experiment 2 PWR-N4 2x4.27 GW th
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INPC2007-TokyoLhuillier David - CEA Saclay - France3
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INPC2007-TokyoLhuillier David - CEA Saclay - France4 Accurate Simulation of Reactor Antineutrino Spectra Determine normalization and shape for phase 1 (dominant error) Use near detector to validate studies of applied neutrino physics: - Power measurement - Non-proliferation
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INPC2007-TokyoLhuillier David - CEA Saclay - France5 Principle of our Approach Evolution code: MURE fissile mat. + FY neutron flux Core geometry isotope abundances spectra database for all isotopes branch spectrum: BESTIOLE nuclear database exp. spectrum models Weighted Total and e - energy spectra with complete error treatment
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INPC2007-TokyoLhuillier David - CEA Saclay - France6 Evolution Code MURE MCNP Utility for Reactor Evolution Neutron flux automatically adjusted to total power parameter Evolution equations and time step sizes validated, propagation of fission yield error Account for neutron capture ( V. Kopeikin et al., Phys. Atom. Nucl. 67 (2004) 1963 ) Working on the geometry of a N4 reactor core
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INPC2007-TokyoLhuillier David - CEA Saclay - France7 Simulation of Chooz Reactors 2 PWR - N4 2x4.27 GW th Control rods (Instrumentation, Poisons…) Zircalloy 205 Assemblies 264 rods Fuel Assembly (0.2x0.2x4.8m) Fuel rod (D: 0.8 cm ; h:4.8 m) Fuel UO 2 pellets (2.1, 2.6, 3.1 % enrichment) - Fuel: enriched Uranium - Moderator/Coolant: Light pressurized Water (155 Bar, 600K) CPU limited, working on suitable sym. and approx. Full power and burn up info from electricity company during data taking Core
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INPC2007-TokyoLhuillier David - CEA Saclay - France8 Building Total e - and Spectra Collect all available exp. info on individual branches Remaining short-lived, high Q , nuclei described by nuclear models. Propagate all errors and compute correlations for any combination of fissile materials and any irradiation time. Final cross-check with integral measurements. dN/dE = n Y n (Z,A,t) i BR n,i P(E,E 0 i,Z) Fission yields branching ratios for decay branch i with endpoint E 0 i shape Strategy Strategy: Reactor spectrum: Sum of “n” isotopes of “i” branches
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INPC2007-TokyoLhuillier David - CEA Saclay - France9 P(E,E 0 i,Z) Coulomb corrections Phase space Spectral Shape factor Well controlled for allowed and forbidden unique transitions. S n (E) E 0 =E e +E for each branch info on all branches unambiguous conversion to spectrum spectrum: spectrum: F(Z,E). pE(E 0 i -E) 2 Energy Spectrum
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INPC2007-TokyoLhuillier David - CEA Saclay - France10 Integral Validation electron e 235 U 1.5 days Agreement within 1 up to 6 MeV 950 nuclei, ~10000 branches Validation of spectrum shape No absolute normalization yet
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INPC2007-TokyoLhuillier David - CEA Saclay - France11 Error Bars Expect final error bar comparable to integral data: BR, E 0, Shape included, working on fission yields error Computation of correlations on progress -->Significant gain in sensitivity to shape distortions because most errors induce large correlations ( P th, Y, BR, E 0 ). Good control of low energy part [1.8-6] MeV Relevant for normalization of phase 1
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INPC2007-TokyoLhuillier David - CEA Saclay - France12 Power Measurement Burn up effect: Project of miniature detector based on Double Chooz concept To be installed ~10m from reactor core Unique tool for cross-calibration of reactor cores !
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INPC2007-TokyoLhuillier David - CEA Saclay - France13 Non Proliferation 235 U 239 Pu E/fission201.7 MeV210.0 MeV Mean energy 2.94 MeV2.84 MeV /fission > 1.8 MeV 1.921.45 for interaction 3.2 10 -43 cm 2 2.7 10 -43 cm 2 For a fixed thermal power, the measured e fluxes from pure 235 U or 239 Pu would differ by 55%… but realistic scenario implies tiny effect.
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INPC2007-TokyoLhuillier David - CEA Saclay - France14 Conclusion Promising preliminary results for normalization of Double Chooz phase 1. -Original approach with complete treatment of error bars and their correlations (expected to be large) Same simulation package is a key element of future applied physics: -Project of 2-3%power measurement with miniature detector -non-proliferation. Looks difficult, first goal is to determine detection threshold for removed Pu mass and point out critical unknown nuclei to increase sensitivity
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INPC2007-TokyoLhuillier David - CEA Saclay - France15 Backup Slices
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INPC2007-TokyoLhuillier David - CEA Saclay - France16 Double Chooz Concept P( e e ) = 1-sin 2 (2 13 )sin 2 ( m 2 31 L/4E) Near detector Far detector Disappearance experiment Clean measurement of 13 flux : 10 21 e /s Nuclear power station 2 cores: 4.27 GW th Near detector ~280 mFar detector 1050 m e e, , 2.5 10 -3 eV 3.0 10 -3 eV
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INPC2007-TokyoLhuillier David - CEA Saclay - France17 Expected Oscillation Signal Far Spectrum Near Spectrum Far/Near ratio sin 2 (2 13 )=0.12 m 2 atm = 3.0 10 -3 eV 2 After 3 years Assuming:
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INPC2007-TokyoLhuillier David - CEA Saclay - France18 Previous Studies Theoretical approach : Klapdor & Metzinger microscopic calc. of trans. matrix elements (PLB82 + PRL82), Vogel et al. for 238 U Integral spectra measured by Schreckenbach et al. (at better than 2% until 8 MeV) & Hahn et al. @ILL 235 U, 239,241 Pu targets, (PLB218(1989)365) but conversion : global fit including 30 arbitrary contributions: global shape uncertainty from 1.3%@3MeV to 9%@8MeV FP contributions : measurements of Tengblad et al. (NPA503(1989)136) 111 nuclei @ISOLDE don’t agree with the experimental integral spectra (important errors : 5% at 4MeV, 11% at 5MeV and 20% at 8MeV) Chooz and Bugey : energy spectrum and flux in agreement with Scheckenbach et al. + Vogel et al. for 238 U, 1.9 % error on reactor e flux
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INPC2007-TokyoLhuillier David - CEA Saclay - France19 Exp. Spectra of Fission Products 2211 48 nuclei in perfect agreement with our database Remaining 63 replaced. Correct error estimate requires careful treatment of fit correlations 111 fission products measured by Tengblad’s et al at ISOLDE
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INPC2007-TokyoLhuillier David - CEA Saclay - France20 Bestiole Data Base root and ascii formats 950 nuclei ~10000 branches 500 -n branches Interfaced to various sources of information tag all relevant info (forbiddenness, level of approx., …) BDB
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INPC2007-TokyoLhuillier David - CEA Saclay - France21 Electron spectra Error Bars Requires spin and parity of nuclear levels No predictions for non-unique transitions Use envelop of illustrated shapes to determine error (extra info from exp. shape factors) Spectrum Shape Quote preliminary ±2.5% sys. error
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INPC2007-TokyoLhuillier David - CEA Saclay - France22 Errors on all branches treated as independent…. Converges as Error Bars BR From ENSDF nuclear database:
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INPC2007-TokyoLhuillier David - CEA Saclay - France23 Treatment of Correlations 2 test of two independent data sets: Generalized 2 test with correlated errors:, Adapted to different studies: -Oscillations: data (R) vs simul (S) -Non prolif: simul vs simul Numerically computed Expect large gain in sensitivity to shape distortions because most errors induce large correlations ( P th, Y, BR, E 0 ).
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INPC2007-TokyoLhuillier David - CEA Saclay - France24 Models for Unknown spectra BESTIOLE + Tengblad et al.(JEF2.2) + Qbeta approx BESTIOLE +Tengblad et al. (JEF2.2) + Gross Theory from ENDFBVI, JENDL and JEFF3.1
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INPC2007-TokyoLhuillier David - CEA Saclay - France25 Pandemonium Effect 0 0 Z N A Z-1 N’ A If not included in database: - Underestimation of the low E part of the spectrum w.r.t. high energy part - Tengblad’s measurement, not sensitive to pandemonium, partly correct for this effect det drops fast with E + difficult analysis of continuum
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INPC2007-TokyoLhuillier David - CEA Saclay - France26 Previous Power Measurements
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INPC2007-TokyoLhuillier David - CEA Saclay - France27 SONGS San Onofre Nuclear Generating Station Lawrence Livermore and Sandia National Labs Detector located in tendon gallery: det ~ 10% 469 evts/day Evidence for burn up effect (?)
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