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A Tale of the Three Cities Prelude to the Long Range Plan It was the best of times, it was the worst of times, it was the age of wisdom, it was the age of foolishness, it was the epoch of belief, it was the epoch of incredulity, it was the season of Light, it was the season of Darkness, it was the spring of hope, it was the winter of despair... – in short, the period was so far like the present period, that some of its noisiest authorities insisted on its being received, for good or for evil, in the superlative degree of comparison only. -A Tale of Two Cities (1859) by Charles Dickens. John Kelley NCSU, TUNL & US Nuclear Data Program
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A Simple view of Nuclear Data? Utilities, Applications, Annals of Knowledge Validation Refinement Discovery Data & Science
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Provides the bridge between Basic Science and Applied Science Motivates curiosity of the unknown Nuclear Data Extends our ability to accomplish new feats Helps us understand the world around us
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Provides the bridge between Basic Science and Applied Science Motivates curiosity of the unknown Nuclear Data merges what we can measure with what we can understand. Extends our ability to accomplish new feats Helps us understand the world around us
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USNDP and the Long Range Plan USNDP is managed by the DoE Office of Science Long range plan provides offices with community input to establish priorities. 2007 LRP “The mission of the USNDP is to collect, evaluate, and disseminate nuclear physics data for basic nuclear physics and applied nuclear technology research” “The nuclear data infrastructure provided by the USNDP impacts governmental, educational, commercial, and medical organizations in United States, and is part of the U.S. commitment to the international nuclear data networks.” “It is evident that the need for convenient access to nuclear data is rapidly increasing… The U.S. users are almost equally divided among government, education, and all other types of organizations… maintain a high level of expertise in the area of nuclear data evaluation to assure the continuation of the nuclear databases with sufficient breadth and quality to meet the requirements of advanced computational applications.”
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Primary Activities of USNDP Evaluation: Evaluated Nuclear Structure Data File (ENSDF/IAEA) Evaluated Nuclear Data File (ENDF) Compilation: Nuclear Science Reference database (NSR) eXperimental Unevaluated Nuclear Data Library (XUNDL) EXperimental nuclear reaction data (EXFOR/IAEA) Dissemination: NNDC Website Repackaging/ taylored user interfaces: NuDat, Nuclear Data Sheets, Table of Isotopes RIPL, Medical Internal Radiation Dose Program, MCNP, GEANT4, CINDER90, etc… Measurement: Growing effort to include an experimental component. Basic Science, Horizontal studies, Data for validation studies.
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Overview Of Structure Database ENSDF ENSDF is the only Nuclear Structure database that is updated continuously – contains information for ALL nuclei and ALL nuclear level properties & radiations – currently contributed by members of the Nuclear Structure and Decay Data Network, under auspices of IAEA. It is maintained by NNDC and the NSDD role is indispensible! XUNDL compiled recent Nuclear Structure data base aims to fill the gap between ENSDF evaluations. Detailed up-to-date (1-2 months) compilation that can include interaction with authors near date of publication. No viable alternative exists in the world! MIRD RADWARE Monte-Carlo Codes MCNP, GEANT, EGS4 ORIGEN, CINDER90 NUBASE RIPL ORTEC & CANBERRA ENSDF Applications ENDF, JEFF, JENDL … Simulations Basic NP Research RNAL PGAA NuDat astrophysics IE
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The Critical Issue we face is, What is Nuclear Data’s role in solving problems? Basic Science – We are always increasing our capacity to solve difficult fundamental problems – New data improves our scientific understanding Homeland Security – Interrogation in search of SNM – Stockpile Stewardship Interdisciplinary science contributions – – Nuclear physics inputs play a greater role for interpreting observational results Refinement of prior data has an impact
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HIGS Facility Compton Backscattered Photons Monoenergetic Neutron Sources at TUNL DD, DT, PT, and PLi Facilities at Triangle Universities Nuclear Laboratory are optimal to contribute in these areas
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Basic Science We are always increasing our capacity to solve difficult fundamental problems New data improves our scientific understanding 1.NRF to measure the separation of the 20 Ne 1 + /1 - parity doublet 2.NRF to characterize astrophysically important 22 Ne+ resonances 3.Unambiguous identification of 12 C 2 + 2
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NRF to Characterize Astrophysically Important 22 Ne+ Resonances. U. Giesen et al., NPA561 (1993) 95 C. Ugalde et al., PRC 76 (2007) 25802 Data collected using 22 Ne( 6 Li,d) was insufficient to characterize the competition between ( ,n) and ( ) reactions in the region of interest. Resonance energies and Spin parity values needed improvement.
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Ex=10.03 (11) MeV =800 (130) keV 0 =60 (10) meV UCONN/Weizmann Institute of Science/ TUNL Optical TPC - CO 2 80% + N 2 20%
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Homeland Security Interrogation in search of SNM Stockpile Stewardship 1.NRF to discover new dipole excitations in SNM actinides 2.Neutron fission product yield studies
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13 discrete de-excitations were identified for the first time in the from 1.6 to 3.0 MeV. This includes 10 to the ground state, two branching transitions to the third excited state at 46.2 keV and one unresolved transition in 235 U. E. Kwan et al., Phys. Rev. C 83, 041601(R) (2011) 238 U Over 105 new excited low-spin states in 238 U were observed at γ-ray beam energies from 2.0 to 5.5 MeV. 80 E1 and 25 M1 states were identified Samantha Hammond et al., Phys. Rev. C 85, 044302 (2012 ) 235 U New Levels in Actinides Identified using Nuclear Resonance Fluorescence at HIGS
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Fission Products Yield Study Long-standing difference between LLNL and LANL with respect to selected fission product data 239 Pu(n,f) 147 Nd There were no 147 Nd data between 1.9 and 14 MeV
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Monoenergetic Neutron Sources at TUNL: dd, dt, pt & pLi 2 H gas From VdG accelerator p or d n One thick target ~0.2 g/cm 2 Two thin targets ~10 μg/cm 2 Dual fission chamber n-detector
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Design and fabricate three fission chambers: one for 239 Pu, one for 235 U, and one for 238 U Dedicated thin (~10 μg/cm 2 ) 235,238 U and 239 Pu foils electroplated on 0.5” titanium backing ★ Dedicated thick (200 - 400 mg/cm 2 ) 235 U (93.27%) 238 U (99.97%) and 239 Pu (98.4%) targets Fission chamber efficiency 100%, confirmed with activation measurements ★ Made by LANL Excellent / fission separation alpha fission FragmentE (keV)'T 1/2 I % 95 Zr756.725 1264.032 d 654.38 % 22 97 Zr743.36 316.749 h 893.09 % 16 105 Rh318.9 135.36 h 619.1 % 6 127 Sb685.7 53.85 d 536.8 % 2 131 I364.489 58.0252 d 681.5 % 5 132 I954.55 91.387 h 1517.6 % 5 132 Te228.16 63.204 d 1388 % 3 133 I529.872 320.83 h 887.0 % 23 135 Xe249.794 159.14 h 290 % 3 140 Ba537.261 912.7527 d 2324.39 % 22 141 Ce145.443 3432.508 d 148.29 % 20 143 Ce293.266 233.039 h 642.8 % 4 147 Nd531.016 2210.98 d 113.37 % 11
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Interdisciplinary science contributions Nuclear physics inputs play a greater role for interpreting observational results 1.Identify M1 states in nuclei important for neutrino observations 2.Measure neutron induced cross sections on materials prevalent in low-rate underground experiments
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Identify M1 state in nuclei important for neutrino observations
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New Proposed experiments at HIGS
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Measure neutron induced cross sections on materials prevalent in low- rate underground experiments http://collargroup.uchicago.edu/laboratory.html XENON100XENON100 Collaboration Phys.Rev. D83 (2011) 082001
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Tornow’s group has leveraged significant NNSA support to create an infrastructure for (n,xn) studies
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Tornow’s (n,xn) studies
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Validation Refinement Discovery Data & Science US Nuclear Data Program Key is to meet the users needs
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