Applications and Interdisciplinary Research at TUNL

1. Applications and Interdisciplinary Research at TUNL • Homeland Security • Faculty: M.W. Ahmed, H.R. Weller and Y. Wu; C.R. Howell and W. Tornow • Facility: HIGS • Funding: DHS/DNDO-ARI [2 grants: (1) polarized fission and (2) NRF] 2. National Nuclear Security Faculty: G. Mitchell; C.R. Howell and W. Tornow Facility: DANCE at LANSCE, TUNL tandem lab and HIGS Funding: DOE/NNSA [3 grants: (1) neutron-induced reactions and (2) NRF] 3. Energy Faculty: M.W. Ahmed and H.R. Weller Facility: TUNL tandem lab Funding: Tri Alpha Energies, Inc. 4. Interdisciplinary Faculty: C.R. Howell; T.B. Clegg and H.J. Karwowski Facility: TUNL tandem lab Funding: DOE/BER

2. Photonuclear Reaction Measurements at HIGS • Photonuclear Measurements on Actinides • To measure data for photon-induced nuclear reactions that are important for development of technologies for remote remote analysis of materials and interrogation of cargo using g-ray beams and for advancing understanding of the structure of heavy nuclei. • To educate the next generation of nuclear physicists in research areas and techniques relevant to national nuclear and homeland security. Nuclear Resonance Fluorescence (NRF) Measurements Faculty: C.R. Howell and W. Tornow Funding: DHS/DNDO-ARI and DOE/NNSA Photofission Induced with Polarized g-ray Beams Faculty: M.W. Ahmed and H.R. Weller Funding: DHS/DNDO-ARI

3. Non-Intrusive Active Interrogation Systemss(g,g’) data using Nuclear Resonance Fluorescence (NRF) Need to characterize states in actinides that can be excited by dipole EM transitions with g-ray energies 2 < Eg < 4 MeV Tunable g-ray source Courtesy LLNL

4. Objectives of NRF Measurements • Search for states that can be excited by dipole EM transitions (2 < Eg < 4 MeV) • Determine: • Integrated cross section • Branching ratios • Spin and parity of the excited states (for nuclei with J=0+ ground state) • Isotopes:240Pu, 237Np, 233U

5. The Challenge of finding low-spin states at Ex > 2 MeV

6. Challenge of finding low-spin states at Ex > 2 MeV(non band states) 240Pu

7. NRF Measurement Strategy • Use Bremsstrahlung beam to conduct a search for dipole transitions over a broad g-ray energy range, e.g. (2 < Eg < 4 MeV) • Next use monoenergetic g-ray beam to make high sensitivity measurements at selected energies based on results obtained with bremsstrahlung beams. Use linear polarization to provide information about the multipolarity of the observed g-ray transitions.

8. Search for low-spin states in 240Pu with bremsstrahlung beam • Discovered 9 g-ray transitions to the ground state • Measured branching ratio between transition to the ground state and the 1st excited states B.J. Quiter et al., Phys. Rev. C 86, 034307 (2012) Measurements made at the High Voltage Research Lab. at MIT bremsstrahlung beam produced by 3-MeV electron beam

9. Experiment Setup for NRF Measurements at HIGS PIs: C.R. Howell and W. Tornow

10. 240Pu: Example TOF and g-ray Energy Spectra Eg = 2.55 MeV, horizontal HPGe detector (5 hrs 21 min)

11. Energy (keV) Jπ 1+/- Ex 240Pu: Determination of Spin and Parity Eg = 2.55 MeV(5 hrs 21 min) 2+ 42.8 0+ 0.0 240Pu

12. Concept for material analysis – Polarized Photofission Faculty: M.W. Ahmed and H.R. Weller φ = 90° φ = 0° • Polarized g-ray induces fission of target nuclei • Prompt neutrons are detected both parallel and perpendicular to the plane of polarization of the incident g-ray g-ray beam

13. Setup for photofission measurements

14. Implementation of concept Fission Neutrons No Neutrons Fission + (g,n) Neutrons Clean Signal 238U Neutrons Eg(MeV) 5.7 6.2 Fission Threshold (g,n) Threshold • Typical energy range Eg = 5.8 - 7.0 MeV • Only other stable isotopes which can produce neutrons at theseenergies are 2H and 9Be • The neutron energy detection threshold is 1.5 MeV • All neutrons are fissionneutrons

15. Example of neutron assembly of fissile vs nonfissile nucleus in Polarized Photofission

16. Measurements of neutron assembly in polarized photofission nonfissile fissile

17. Applied and Interdisciplinary Research in the tandem lab at TUNL • (n,2nx) and (n, f) cross section measurements on actinides • Faculty: W. Tornow and C.R. Howell • 2. Plant research with short-live radioisotopes • Faculty: C.R. Howell • 3. Water purification by filtration • Faculty: C.R. Howell

18. Plant Physiology Studies Using Radioisotope Tracing Duke Physics: Calvin Howell,Alexander Crowell, Laurie Cumberbatch, Brent Fallin Duke Biology: Chantal Reid Jefferson Lab: Brian Kross, SeungJoon Lee, Jack McKisson, John McKisson, Andrew Weisenberger, Wenze Xi, Carl Zorn University of MD: Mark Smith West Virginia University: Alexander Stolin Federal Sponsors: DOE: Office of Nuclear Physics DOE Biological and Environmental Research NSF: Biological Infrastructure

19. “Industrial Revolution” Evidence for Influence of Human Activities on Atmospheric CO2 Levels

20. Long-time scale Picture of Atmospheric CO2 Levels from Antarctic ice core samples Current atm. CO2 concentration Milanković cycles: Earth’s orbital eccentricity: 100 kyrs Earth’s axis tilt (22.1 ↔ 24.5): 42 kyrs Earth’s axis wobble: 23 kyrs

21. Research Objectives 1. Primary food source on Earth 2. Helps regulate atmospheric CO2 levels • to identify and measure the effects of changes in environmental conditions on the allocation of carbon (sugars) and nitrogen; • to measure the physical parameters in plant physiology models of substance translocation and allocation, e.g., phloem loading and root exudation; • to measure plant responses to herbivores; and • to measure dynamic change in photorespiration rate in response to changes in environmental conditions.

22. Isotope production and use p + 14N 11C + α ≈100 m

23. Plant Physiology Research using Radioisotope tracing Goal:Explore dynamical response of plants to changes in its local environment and external resource availability • Radioisotopes produced in tandem lab • Measurements made at the Phytotron (in environment controlled growth chamber) Larry Cumberbatch, Duke Medical Physics, PhD thesis project Collaboration with JLab detector group Local Participants: Faculty:Howell, Reid (Biology) Research Scientist: Crowell PhD Student: Cumberbatch Published in Physics in Medicine and Biology (2012)

24. PhytoPETSystem • Developed at JLAB • Based on H8500 PSPMT and pixelated LYSO crystals • Flash ADC readout over Gb ethernet • Multiple configurations possible Weisenbergeret al., NIM A, 718 (2013) 157.

25. Corn Growth Conditions • Young corn plants (~ 1-2 weeks old) labeled with 11CO2 • B73 variety – has a sequenced genome • Transplant into clear media (Gelzan) to facilitate registration of root images

26. Translocation of Sugars

27. Quantitative Analysis 2 1 3 4 v (1 → 2) ≈ 6.0 mm/min v (2 → 3) ≈ 0.1 mm/min v (3 → 4) ≈ 0.3 mm/min

28. Characterization of membranes for water purification by Rutherford Backscattering Spectrometry (RBS) and Elastic Recoil Detection (ERD) analyses Students: Peter Attayek (UG), Eliot Meyer, Lin Lin, Grayson Rich, Joshua Powell Faculty: Orlando Coronell, Thomas Clegg Collaborators: Hugon Karwowski, Nalin Parikh (Left) A new target system was developed to enable analysis of organic samples by Rutherford backscattering spectrometry (RBS) and elastic recoil detection analyses (Below) The target system is used to study the active layer of membranes for water desalination and reuse, including their elemental composition and charge density Attayek et al., Submitted for publication