Nuclear reactions studies at NFS for improved nuclear data for science and technology

Transcription

1 Nuclear reactions studies at NFS for improved nuclear data for science and technology Stephan Pomp Department of physics and astronomy Uppsala University Spiral2 week, November 2016

2 What I ll talk about: What do you mean with Nuclear data? And what are the applications? An example: the complete nuclear physics lab (aka fission) So where do you go? NFS And what will be done there? Spiral2 week, November 2016 Slide 2 of 21

3 Nuclear data: what s it about? Nuclear physics identify needs provide data Applications (demands and needs from users) Theoretical: Nuclear reaction modelling Experimental: Nuclear physics measurements Detection and measurement techniques Computational: Simulation codes Analysis methods Nuclear data evaluation methodology Medical: Nuclear medicine, Dosimetry, Drug development, Regenerative medicine, Materials: Semiconductors, Radiation damage, Energy: Fission (GenIV, fuel cycle, ), Fusion, Safety and Security: Safeguards, Environment: Radioecology, Science: Archaeology, Astrophysics, Geology, Spiral2 week, November 2016 Slide 3 of 21

4 ND are connected to many SDGs! Aldo Malavasi, IAEA at ND2016 Spiral2 week, November 2016 Slide 4 of 21

5 NuPECC Spiral2 week, November 2016 Slide 5 of 21

6 Nuclear data: how is it done? Nuclear physics experiments Requirements (sensitivity analysis) Nuclear data evaluation End-user applications Nuclear physics model codes Covariances! QA: Reproducibility, etc. (see, e.g., the TENDL project) Koning and Rochman, Nucl. Data Sheets 113 (2012) 2841 Spiral2 week, November 2016 Slide 7 of 21

7 The complete nuclear physics lab (aka fission) Fission is a slow, dynamic process which can be viewed as nuclear shape evolution... Fission comprises many aspects of nuclear physics. E.g. structure of very deformed nuclei far from stability A.V. Karpov et al., J. Phys. G: Nucl. Part. Phys. 35 (2008) Nuclear shape evolution with Langevin equations; courtesy S. Chiba Spiral2 week, November 2016 Slide 8 of 21

8 Some fission challenges Questions: Where does the excitation energy go? When does the freeze-out of fragment properties occur? Do scission neutrons exist? Linked to that: Prompt neutrons? Isomeric yields? A. Göök et al., PRC 90 (2014) Cf(SF) New theoretical ideas: Energy sorting mechanism based on the constant temperature model: Schmidt and Jurado, PRC 83 (2011) (R) 237 Np(n,f) GEF code K.-H. Schmidt et al., Nucl. Data Sheets 131 (2016) Excitation energy Spiral2 week, November 2016 Slide 9 of 21

9 n (A) Yield ratio Specific need: fission yields There are specific needs from application (e.g., knowledge of fission yields for various fuel cycle or nucleosynthesis scenarios). Such needs can be fulfilled by direct measurements combined with theoretical developments that need guidance from other experimental input (e.g. n(a)). Impact on n(a) on fission yields in the 234 U case: Average (AV) E n =5 MeV Heavy (HE) E n =5 MeV Yield ratio AV/HE 5 MeV E n =0 MeV Mass (u) Post neutron emission Mass (amu) A. Al-Adili, et al, Phys. Rev. C86 (2012) Spiral2 week, November 2016 Slide 10 of 21

10 So where do we go? Spiral2 week, November 2016 Slide 11 of 21

11 Slide courtesy Xavier Ledoux Neutron spectra provided at NFS Continuous spectrum 40 MeV d+ Be (6 mm) Quasi-mono-energetic spectrum p+ 7 Li -> n + 7 Be Q= MeV 30 MeV p + Li Rotating thick converter Convertissueur rotatif Thin converter ND2016, Bruges September 2016

12 NFS is one of a few QMN facilities Rad. Prot. Dosim. 161 (2014) Spiral2 week, November 2016 Slide 13 of 21

13 and a competitive/complementary white neutron source Plus p, d and a beams! More on NFS: Talk by Xavier Ledoux on Wednesday NFS : 40 MeV d + Be WNR : Los Alamos n-tof 2 : CERN n-tof 1 : CERN GELINA : Geel E n : from 0,1 MeV to 40 MeV Good energy resolution Reduced g flash Low instantaneous flux Slide courtesy Xavier Ledoux Spiral2 week, November 2016 Slide 14 of 21

14 Intended activities at NFS A first call for experiments at NFS was issued this spring. Constraints in the delivered first beams (parallel with commissioning): - only p and a beams at 88 MHz - hence ToF very difficult and preference of QMN See talk by Xavier Ledoux Therefore only a limited number of LoI have been presented as proposals. At the PAC in June 2016, seven proposals for experiments have been granted beam time. Spiral2 week, November 2016 Slide 15 of 21

15 Letters of Intent not yet submitted to PAC Neutron induced reactions studies : Study of pre-equilibrium process in (n,xn) reaction, X. Ledoux Comparison between activation and prompt spectroscopy as means of (n,xn) cross section measurements, M. Kerveno Scintillating ionization Chamber for ALpha particle Production in neutron induced reaction, G. Lehaut Fission : Fission fragment distributions and neutron multiplicities, D. Doré Study of the fission process and fission cross-section measurements, G. Bélier Measurement of prompt fission gamma-ray spectra in fast neutron induced-fission of actinides, J.M. Laborie Gamma-rays spectroscopy and lifetime measurements at NFS, A. Dijon Cross-section reaction measurements by activation technique : Measurement of cross-sections of deuteron-induced reactions on Ni and Zn, J. Grinyer Biology : Response of Mammalian cells to neutron exposure, C. Hellweg Investigation of 211 At and 64 Cu medical radioisotope production at NFS, J. Grinyer Detector development : Neutron spectrometer characterization for LMJ project, B. Rossé Spiral2 week, November 2016 Slide 16 of 21

16 10 submitted proposal: 7 accepted in this first round NUM Title Spokesperson Reaction model E712 Measurement of (n,xn) reaction cross sections on U238 G. Bélier, CEA-DAM Fission Fusion Radionuclei for medical applications E721 E713 E718 LIONS - Light-Ion Production Studies with Medley at the NFS facility Prompt fission neutron spectra measurement in neutron induced fission reactions Fission fragment angular distribution and fission cross section measurements relative to elastic NP scattering at 30 MeV A.V. Prokofiev, Uppsala University B. Laurent, CEA-DAM D. Tarrio, Uppsala University Excitation functions of short-lived isotopes in proton induced E. Simeckova, NPI, Rez reactions on nat Fe E715 Neutron-induced activation reactions A. Klix, KIT E717 Alpha-induced reaction cross-section measurements on natural and enriched Zn Measurements of the excitation function for the production of possible candidates for targeted alpha therapy at SPIRAL2 Astrophysic E719 Precise direct measurements of the 28 Si(p,γ) 29 P and 29 Si(p,γ) 30 P reaction rates to understand the origin of presolar nova grains J. Grinyer, GANIL G. de France, GANIL B. Bastin, GANIL Instrumentation E720 Measurement of the absolute neutron detection efficiency of FAZIA telescopes E. Bonnet, GANIL Spiral2 week, November 2016 Slide 17 of 21

17 Medley Light-ion production Cancer therapy and dosimetry (H, C, O, Ca,...) E721 Radiation effects in microelectronics (SEU; single event upsets) Si, O,... Silicon and oxygen data is needed for: Energy applications (GenIV, fusion) Construction material: Fe, Cr, Fuel: U, Th, Coolant: Pb, Bi, Na, 16 O(n,α) affects reactor reactivity, 25% of the helium production Medley Evacuated chamber DE-DE-E technique + angles double differential xs Tippawan et al., Phys. Rev. C 79, (2009). Spiral2 week, November 2016 Slide 18 of 21

18 Rel. spec. fluence neutron spectra and standards Add PPACs, and a target arrangement of 235 U CH U for simultaneous measurement of neutron standards vs primary H(n,n) standard with minimal syst. uncert. Jansson et al., NIM A 794 (2015) 141, and Tarrío et al., submitted to ND2016. Neutron energy (MeV) 7 Li(p,nx) with E p = 49.5 MeV and 4 mm Li target as measured at TSL Spiral2 week, November 2016 Slide 19 of 21

19 FALSTAFF Four arm clover for the Study of Actinide Fission Fragments Spectrometer for fission fragment detection in coincidence o Kinetic energy o Masses BEFORE and AFTER evaporation (-> n(a)) o Charge Slide courtesy Diane Doré Mass before evaporation 2V method TOF : Good time resolution (s) <150 ps o Large solid angle (~1% of 4p) o Good position resolution (1.2 mm) Mass after evaporation EV method Energy & TOF o Good energy resolution (~1%) o Charge identification (de profile) at NFS in 2018 Spiral2 week, November 2016 Slide 20 of 21

20 50 physicists from 15 labs are eagerly waiting for first beam and running experiments at NFS! CEA/DAM/DIF, F-91297, Arpajon, France CEA/DSM/IRFU/SPhN, Saclay, France CENBG, Gradignan, France LPC, Caen, France IPHC, Strasbourg, France NPI, Řež, Czech Republic Uppsala University, Uppsala, Sweden KIT, Karlsruhe, Germany GANIL, Caen, France NIPNE, Bucharest, Romania JRC/IRMM, Geel, Belgium CEA/DEN, Cadarache, France IPNO, Orsay, France CIMAP, Caen, France Culham Centre for Fusion Energy, United Kingdom Spiral2 week, November 2016 Slide 21 of 21

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