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A Tale of the Three Cities

A Tale of the Three Cities. Prelude to the Long Range Plan

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A Tale of the Three Cities

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  1. 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

  2. A Simple view of Nuclear Data? Discovery Validation Utilities, Applications, Annals of Knowledge Data & Science Refinement

  3. Nuclear Data Motivates curiosity of the unknown Helps us understand the world around us Extends our ability to accomplish new feats Provides the bridge between Basic Science and Applied Science

  4. Nuclear Datamerges what we can measure with what we can understand. Helps us understand the world around us Motivates curiosity of the unknown Extends our ability to accomplish new feats Provides the bridge between Basic Science and Applied Science

  5. 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 databaseswith sufficient breadth and quality to meet the requirements of advanced computational applications.”

  6. 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.

  7. Overview Of Structure Database ENSDF ENSDF Basic NP Research Applications ENDF, JEFF, JENDL … ORTEC & CANBERRA Simulations MIRD RIPL Monte-Carlo Codes MCNP, GEANT, EGS4 ORIGEN, CINDER90 IE RNAL PGAA astrophysics NuDat NUBASE RADWARE ENSDFisthe 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 isindispensible! 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!

  8. 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

  9. Facilities atTriangle Universities Nuclear Laboratory are optimal to contribute in these areas Monoenergetic Neutron Sources at TUNLDD, DT, PT, and PLi HIGS FacilityCompton Backscattered Photons

  10. Basic Science • We are always increasing our capacity to solve difficult fundamental problems • New data improves our scientific understanding • NRF to measure the separation of the 20Ne 1+/1- parity doublet • NRF to characterize astrophysically important 22Ne+a resonances • Unambiguous identification of 12C 2+2

  11. NRF to Characterize AstrophysicallyImportant 22Ne+ a Resonances. Data collected using 22Ne(6Li,d) was insufficient to characterize the competition between (a,n) and (a,g) reactions in the region of interest. Resonance energies and Spin parity values needed improvement. U. Giesen et al., NPA561 (1993) 95 C. Ugalde et al., PRC 76 (2007) 25802

  12. UCONN/Weizmann Institute of Science/ TUNL Optical TPC - CO2 80% + N2 20% Ex=10.03 (11) MeV G=800 (130) keV Gg0=60 (10) meV

  13. Homeland Security • Interrogation in search of SNM • Stockpile Stewardship • NRF to discover new dipole excitations in SNM actinides • Neutron fission product yield studies

  14. New Levels in Actinides Identified using Nuclear Resonance Fluorescence at HIGS 235U 238U Samantha Hammond et al., Phys. Rev. C 85, 044302 (2012) E. Kwan et al., Phys. Rev. C 83, 041601(R) (2011) • 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 235U. • Over 105 new excited low-spin states in 238U were observed at γ-ray beam energies from 2.0 to 5.5 MeV. • 80 E1 and 25 M1 states were identified

  15. Fission Products Yield Study Long-standing difference between LLNL and LANL with respect to selected fission product data 239Pu(n,f)147Nd There were no 147Nd data between 1.9 and 14 MeV

  16. 2Hgas Monoenergetic Neutron Sources at TUNL: dd, dt, pt & pLi n-detector Dual fission chamber n p or d From VdGaccelerator One thick target ~0.2 g/cm2 Two thin targets ~10 μg/cm2

  17. Dual Fission Chamber: The Renaissance of the NIST idea • Design and fabricate three fission chambers: one for 239Pu, one for 235U, and one for 238U • Dedicated thin (~10 μg/cm2) 235,238U and 239Pu foils electroplated on 0.5” titanium backing★ • Dedicated thick (200 - 400 mg/cm2) 235U (93.27%) 238U (99.97%) and 239Pu (98.4%) targets • Fission chamber efficiency 100%, confirmed with activation measurements • ★Made by LANL Summary of identified fragments for 235U, 238U and 239Pu fission alpha 147Nd(239Pu) Absolute Fission Product Yield-Prelim. Excellent a / fission separation

  18. Interdisciplinary science contributions • Nuclear physics inputs play a greater role for interpreting observational results • Identify M1 states in nuclei important for neutrino observations • Measure neutron induced cross sections on materials prevalent in low-rate underground experiments

  19. Identify M1 state in nuclei important for neutrino observations

  20. New Proposed experiments at HIGS

  21. Measure neutron induced cross sections on materials prevalent in low-rate underground experiments XENON100 Collaboration Phys.Rev. D83 (2011) 082001 http://collargroup.uchicago.edu/laboratory.html

  22. Tornow’s group has leveraged significant NNSA support to create an infrastructure for (n,xn) studies

  23. Tornow’s (n,xn) studies

  24. US Nuclear Data Program Key is to meet the users needs Discovery Validation Data & Science Refinement

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