Nuclear Fusion with Polarized Fuel

Transcription

1 Mitglied der Helmholtz-Gemeinschaft Nuclear Fusion with Polarized Fuel -Some thoughts on the PREFER collaboration - Workshop on Nuclear Fusion with Polarized Fuel Ferrara 2/3 October 2017 Markus Büscher

2 Polarized Fusion Workshop: Warm-up 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 2

3 CO 2 Emissions and Global Warming *) *) for 4 global warming Source: O.Edenhofer(TU Berlin) Erkenntnisseausdem5. Sachstandsberichtdes IPCC KolloquiumFZJ Jülich, Alternative sources of energy (base load) w/o CO 2 emission? 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 3

4 Fusion Energy: What You Find on Google Binds resources that are needed for the fight against climate change The material and technical challenges are extreme The return on renewables has been very much higher. Because renewable technologies are newer, there might still be stones unturned in terms of research Nuclear fusion is 30 years away, and always will be. That's the refrain we've heard, again and again for decades. 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 4

5 Moore s Law 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 5

6 The Lawson Criterion Condition for a fusion reactor: E(Fusion) > E(Heating, ) n"τ $ > 12k )T E, σ, v n: ion density τ $ : confinement time T: ion temperature E, : Energy per fusion σ, : fusion cross section v: ion velocity Density and confinement time large 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 6

7 Magnetic Confinement Fusion Plasma density n= cm 3 ; confinement time τ E = 100 s ITER (>2025) 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 7

8 Inertial Confinement Fusion Plasma density n= cm 3 ; confinement time τ E = s 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 8

9 National Ignition Facility (NIF) 192 Laser (Nd:Glass) 423 TW peak power 1.8 MJ energy Target chamber = 10 m 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 9

10 Laser-induced Production of Fusion-like Plasmas Target Particle beam µm-sized plasma Multi-TW Laser 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 10

11 Fusion Reactions in Laser-induced Plasmas Here: D + D 3 He + n Max-Planck-InstitutfürQuantenoptik(CD 2 foil target) 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 11

12 The Lawson Criterion Revisited n"τ $ > 12k )T E, σ, v n: ion density τ $ : confinement time T: ion temperature E, : Energy per fusion σ, : fusion cross section v: ion velocity External parameters : pressure, temperature, confinement time Intrinsic parameter : fusion cross sectionσ f can this be changed from outside???? 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 12

13 Fusion Reactions è è è D + D 3 He + n + 3,3 MeV D + D T + p + 4, 0 MeV D + T 4 He + n +17, 6 MeV D + 3 He 4 He + p +18,3 MeV 3 He + 3 He 4 He + 2 p +12, 9 MeV è è most promising candidates for fusion reactors no neutrons from a fusion reactor operated with pure 3 He fuel ( 4 He and protons only) 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 13

14 Polarized Fusion: First Ideas See also: The status of polarized fusion, H. Paetz gen. Schieck, Eur. Phys. J. A 44, (2010) 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 14

15 Polarized Fusion: Increased Total Cross Section Helv. Phys. Acta 44, 141 (1971) E I He+d He+p total cross section enhancedby factor kev 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 15

16 Polarized Fusion: Increased Energy Yield Here: inertial fusion Energy yield Enhancement by factor 4 with polarized fuel Relative fusion cross section From: M. Temporal et al.; Priv. comm. 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 16

17 Polarized Fusion: Angular Distributions 1971: D + 3 He 4 He + p Helv. Phys. Acta 44, 141 (1971) Emitted Protons (Neutrons) can be guided (even if only Deuterons are polarized) 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 17

18 The PolFusionProject (2015 / ERC proposal) Measure the polarization dependence of fusion rates in laser-induced relativistic plasmas 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 18

19 2016: Approval of a DFG-RSF project 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 19

20 2017: The PREFER Collaboration Polarization Research for Fusion Experiments and Reactors 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 20

21 PREFER: Work Packages (1) Measurement of ddcross section / PolFusionexperiment (PNPI, Ferrara) Talk by Peter Kravtsov 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 21

22 PREFER: Work Packages (2) Theory / Scattering of two spin-1 particles (PNPI) Talk by Polina Kravchenko 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 22

23 PREFER: Work Packages (3) Polarized molecular beam source (BINP) Talk by DimitriiToporkov 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 23

24 PREFER: Work Packages (4) Construction & test of a Lamb-shift polarimeter (HHUD, FZJ, Ferrara) Talk by Ralf Engels 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 24

25 PREFER: Work Packages (5) Foils of frozen polarized Hydrogen (HHUD, FZJ, BINP) D 2 ice T= 3-10K Cold Head Production of 1 day (>10 21 molecules) is enough to feed a Tokamak for seconds!! 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 25

26 PREFER: Work Packages (6) Theory / Nuclear spins in Laser-induced plasmas (HHUD) Thomas-BMT equation Sokolov-Ternov effect Stern-Gerlacheffect PIC codes 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 26

27 PREFER: Work Packages (7) Nuclear Spins in Laser-induced Plasmas / Experiments (HHUD, FZJ) Multi-TW laser beam Fusion reactions (pol.) Target Does the fusion rate depend on the target polarization? Accelerated Ions µm-sized relativistic plasma Are the accelerated ions polarized? Angular dependence of fusion products? 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 27

28 Generation of Polarized Particle Beams Possible scenarios: Polarization is generated spin flip Stern-Gerlacheffect Polarization is preserved 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 28

29 Polarized 3 He Gas Glass vessels surrounded by permanent magnets (Univ. Mainz) / max. pressure 3 bar Talk by IlhanEngin 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 29

30 GSI Darmstadt Petawatt High-Energy Laser for Heavy Ion EXperiments Flashlamp-pumped Nd:glasssystem Repetition rate: 1 shot per 1.5 hours Long pulse Short pulse Pulse duration ns ps Pulse energy J 250 J Max. intensity W/cm W/cm 2 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 30

31 Polarized Protons from Unpolarized Gas Targets SIOM/Shanghai: Planned measurements at a 10 PW laser Polarimeter for 3 He ions I.Engin et al., DOI: / _5 Magnetic field distribution during bubble acceleration B.Shenet al., Phys.Rev. ST AB 12, (2009) 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 31

32 Proton Polarimetry MeV) 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 32

33 PREFER: Work Packages Who else?? 2 Oct 2017 Workshop on Nuclear Fusion with Polarized Fuel Markus Büscher 33