Laser-Driven Fusion-Triggered Liquid Transmutator

Transcription

1 Laser-Driven Fusion-Triggered Liquid Transmutator T. Tajima, A. Necas, G. Mourou, S. Gales, and M. Leroy TAE, Ecole Polytechnique, IPN Orsay, and U. Strasbourg T. Massard, Y. Brechet, M. Binderbauer, J. Tanner, K. Hattfield, S. David, F. Carre, J. Tommasi, P. Martin, B. Boullis, M. Mizumoto, Y. Fujiie 8 th ICUIL Conference Lindau, Germany Sept. 12, 2018

2 New Philosophy and Science to Fulfill Self-responsibility 20 th Century: Science of Discovery à Tajima (Jan. 18,2005) 21 st Century: Toilet Science: Responsive to societal issues self-inflicted

3 From Kitchen Science to Toilet Science Human are superior in working together via communication, which won out over Neanderthals. They have been extremely good in kitchen science to get to food. However, they have been negligent or weak in thinking toilet science to treat waste. Examples: 1. Petroleum civilization: Convenient modern life ----à Homo Sapiens-triggered climate change 2. Space: Sputnik in à Millions of space debris endanger astronauts and satellites 3. Particle physics: appetite for higher energy acceleration -----à need to compactify and radio-nontoxic, including high energy beam dump 4. Nukes: Only 4 years to get Fermi s Chicago pile (1940) ----à Nowhere to flush radioactive waste

4 Our Toilet for Nukes: Go from Solid to Liquid Safety - Intrinsic safety ---no Fukushima;Chernobyl Thermal expansion and neutron-capture up (as T ) Opera>on at 1 atm - Passive safety: liquid tank=frozen plug ---no Fukushima;Chernobyl - External control knobs increased delayed n (s.a. Hf), control rods, control of n-source - Real-time monitor and AI: liquid transparency - No fuel processing: solid fuel fabrica>on not needed Idaho

5 Idaho National Lab Integral Fast Reactor (1986) back in 1986, we actually gave a small [20 MWe] prototype advanced fast reactor a couple of chances to melt down. It politely refused both times.

6 Motivation for transmutation of MA transmutation of spent fuel MA à Dura0on Reduc0on 1000x Volume Reduc0on 100x F. Carre (2007)

7 Reduction of radiotoxicity (Japanese strategy) s 9 F mf C r MS N L (. ( No Transmutation p 12 A 9 p % transmutation for MA & LLFP F A F % MA & LLFP 10 ( A % F r 7 F T c IP A nat. U (1 ton) 10 5 ALI Ingestion Hazard Index of HLW per One Metric Ton of Fresh Fuel % MA & LLFP 0.2% U ore (1 ton) 100% MA 99.9% MA 99.9% MA & LLFP Time after Reprocessing (year) LLFP : FPs with T 1/2 30 years Mizumoto(JAEA) M. Mizumoto(2006)

8 Neutron Energy Window: MA Fission Triggered (1-15MeV) 14.1 MeV Fusion Neutrons Am 241 Cm 243 Neutron Absorption (Red) vs Fission (Green) Cross Sections 241 Am + n à 242 Am 241 Am + n à FP a + FP b + + (3-7) n s + energy Neutron cross-sections in > 1MeV: Fission > Neutron Absorption 8

9 Our Liquid Transmutator (our toilet ) : Design Safe by Liquid solution-flibe (molten salt with very high boiling pt; passive safety valve; thermal expansion; ) Safe by realtime monitor and control (by passive observation of gamma emission, by laser and laser Compton gamma) Safe operation, including delayed neutron treatments tec. (O(100MW)) Light burden on accelerator-driven Fusion Trigger (flexibility, safety, compact, mobile, inexpensive) O(100kW) Small and low energy Fusion trigger (compact and cheap) O(MW) Possible mixing of Pu into MA: hard for weaponization à Confluence of many technologies : catapult from low-energy laser-driven accelerator-driven fusion, to fusion-triggered fission; safe liquid-phased MSR ; liquid MA monitored / controlled realtime by laser; chemical separation in liquid

10 Energy Catapulting Neutron Multiplying! " #$% &'' ~)* +, Neutrons mul?ply 200 MeV Fission-Q 14 MeV neutrons 140 kev deuteron beam ~10 % deuterons achieve fusion

11 ES accelerator 150 kev deuteron 14 MeV neutron Transmute Pu+MA by fission Electrostatic accelerator neutron source OR Control rods Active laser monitoring Dissolved solution of LiF-BeF 2 (FLiBe) molten salt + Transuranics (Pu, Am, Cm, Np) + Fission products (Sr, Zr, Tc, Te, Cs ) Passive gamma NRF Laser neutron source

12 Laser driven neutron sources a neutron source tank b Transmutation tank c Laser pulse d1 DT or DD fusion neutrons d2 deuteron beam e keyhole f mirror g entrance window h nanometric foil [1-10 nm] i solid titanium-tritium target at the back end of keyhole Single keyhole zoom A B Single keyhole zoom

13 Mourou et al.: Nature Photon. (2013)

14 CAIL (Coherent Acceleration of Ions by Laser) vs TNSA # : the regime our transmutator operates à# from (Tajima et al. 2017)

15 <latexit sha1_base64="6g5nbwpnukw8umaaie8cetahbyq=">aaab+3icbvbns8naen3ur1q/yj16wsyc <latexit sha1_base64="mgz30un7sbg6ylkk7legtjaos90=">aaab8xi Our simulations: Optimal Thickness of Target Coherent Acceleration of Ions by Laser (CAIL) Deuteron energy vs. thickness of foil Energy Emax[MeV] a 0 /a 0 target thickness [normalized to laser intensity] Our simulation Experiment: Steinke et al (2010) Optimum parameters (sweet-spot) for ion acceleration at a 0

16 Highly-energetic Deuterons accelerated by laser in CAIL (Coherent Acceleration of Ions by Laser) Fusion cross section Parameter Value Intensity*, W/cm 2 5x10 17 deuterons Pulse length, fs 45 Beam width, µm 3.6 Laser energy, mj 6 Foil thickness, nm 10 Skin depth, nm 25.3 Electron density 1/cc 4.4x10 22 Critical density 1/cc 1x10 21 Deuteron Energy [MeV] Rep rate, khz 10 Theoretical max ion energy (Tajima et al, 2009; Steinke et al, 2010)

17 <latexit sha1_base64="b6a1fmwwm6hazktpkk0fhw2dcts=">aaab83icbvbns8naej3ur1q/qh69lbbb <latexit sha1_base64="b6a1fmwwm6hazktpkk0fhw2dcts=">aaab83icbvbns8naej3ur1q/qh69lbbbu0le1itq8okxgv2ajptjdtmu3wzc7kyoox/diwdfvppnvplv3ly5aoudgcd7m8zmc Laser accelerator : Efficient coupling ( ~50%) to ions in CAIL The shorter the laser pulse, the higher deuteron acceleration (totally different from TNSA) Very little energy needed per pulse (mj). Scan Laser Pulse Length at = a 0 Efficiency [%] = a 0! L = 2 c Shorter pulse Pulse length [fs] higher efficiency coupling

18 Danke Schoen! 70th Birthday