Presentation on theme: "Fusion Power on Earth Using 3 2 He from somewhere in the Solar System: if NASA and DOE ever cooperate! Dr. Harold Williams Google “Montgomery College Planetarium”"— Presentation transcript:
Fusion Power on Earth Using 3 2 He from somewhere in the Solar System: if NASA and DOE ever cooperate! Dr. Harold Williams Google “Montgomery College Planetarium” http://montgomerycollege.edu/Departments/planet
Abundance of 3 2 He Earth 0.000137% (% He on Earth) Moon embedded in the upper layer of regolith by the solar wind over billions of years) and the solar system's gas giants (left over from the original solar nebula), though still low in quantity (28 ppm of lunar regolith is helium-4 and from 0.01 ppm to 0.05 ppm is helium-3regolithsolar windsolar systemgas giants solar nebulappmhelium-4 Mars in the cold trap on poles? Jupiter, Saturn, and other gas giants Solar Nebulae
Some Earthly Uses of 3 2 He Giorgio Frossati, president of the Dutch dilution refrigerator manufacturer Leiden Cryogenics, says he recently paid $2150 per liter for 50 liters=6.7grams. dilution refrigerator Leiden Cryogenics n 0 + 3 2 He → 3 1 H+ 1 1 H + 0.764 MeV Neutron Detectors; Homeland Security UseNeutron Detectors Useful nuclei for neutron detection 3 He, 6 Li, 10 B, 233 U, 235 U, 237 Np and 239 Pu.
Some Current Problems DOE begins rationing helium-3, Physics Today on June 2010 page 22 DOE begins rationing helium-3
Fusion on Earth with some Neutrons Seems to have been 5 decades away since 1958. Neutrons are the problem unless you want to blow things up! Except in fission reactors neutrons can be thermalized in water and then there is no problem. Fusion occurs in a hot plasma many millions of degrees (so you can overcome the electrical repulsion of the positive charged nuclei) and there is no water in such environments to thermalize.
Some Future Uses of 3 2 He 3 2 He + 3 2 He → 4 2 He+ 2 1 1 p + +12.86 MeV most promising aneutronic fusion process if we had any appreciable 3 2 He fuel. Mining the Moon in Technology Review published by MIT on August 23, 2007 Mining the Moon At the 21st century's start, few would have predicted that by 2007, a second race for the moon would be under way. Yet the signs are that this is now the case. Furthermore, in today's moon race, unlike the one that took place between the United States and the U.S.S.R. in the 1960s, a full roster of 21st-century global powers, including China and India, are competing.
Making 3 2 He Primary way to make Tritium, hydrogen-3, heavy heavy hydrogen on earth; 6 3 Li+n→ 4 2 He(2.05 MeV)+ 3 1 T(2.75 MeV)Tritium Let Tritium decay: 3 1 T = 3 1 H → 3 2 He + +e − +ν e + 18.6 keV; 4,500±8 days (approximately 12.32 years) Beta particles from tritium can penetrate only about 6.0 mm of air, and they are incapable of passing through the dead outermost layer of human skin. Tritium is not good for you if you inhale or eat it.
Some Internet Resources Helium, second most common element in the universe Helium Helium-3, subject of this presentation Helium-3 Helium-4, nucleus is an alpha particle Helium-4 Aneutronic fusion, possibilities Aneutronic fusion Periodic Table of the Elements from Radiochemistry Society Periodic Table of the Elements The Berkeley Laboratory Isotopes Project’s Contemporary Physics Education Projects
Feynman Diagram of the decay of the Neutron, Weak Nuclear Force
NeutronNeutron, n 0 : u +⅔ d -⅓ d -⅓, a baryonbaryon
Free Neutron Decay n 0 → p + + e − + ν e 1.67492729(28)×10 −27 kg 939.565560(81) MeV/c 2 1.0086649156(6) ukgMeV/c 2u mean lifetime of 885.7±0.8 s (about 14 minutes, 46 seconds) mean lifetime Neutrons are often stable in the nucleus.
ProtonProton, p + : u +⅔ u +⅔ d -⅓, a baryonbaryon
Free Pion Decay Lifetime of 2.6×10 −8 s. π + → μ + + ν μ ; π − → μ − + ν μ with probability 0.999877, is a purely leptonic decay into a muon and a muon neutrino. π + → e + + ν e ; π − → e − + ν e second most common decay mode of a pion, with probability 0.000123.sμ +μ −leptonicmuonmuon neutrinoe +e − Lifetime of 8.4×10 −17 s. π 0 → 2 γ with probability 0.98798 and π 0 → γ + e − + e + with probability 0.01198.γe −e + Virtual Pions are what holds the protons and neutrons together in the nucleus.
Standard Model Standard Model of Particles SU(3)xSU(2)xU(1): Strong, Weak, ElectroMagnetism SU U(1)StrongWeakElectroMagnetism
QuarkQuarks NameSymbolMass Mev/c 2 Q (charge) Upu1.7 to 3.3+2⁄3+2⁄3 Downd4.1 to 5.8−1⁄3−1⁄3 Charmc1,270+70−90+2⁄3+2⁄3 Stranges101+29−21−1⁄3−1⁄3 Topt172,000±900 ±1,300+2⁄3+2⁄3 Bottomb4,190+180−60−1⁄3−1⁄3
Quarks combining colorlessly to form Mesons and Baryons
BaryonBaryons List of Baryons: some baryons N (p · n) · Δ · Λ · Σ · Ξ · Ω List of BaryonsNpnΔΛ ΣΞΩ
MesonMesons List of Mesons: some mesons π · ρ · η · η′ · φ · ω · J/ψ · ϒ · θ · K · B · D · T List of Mesonsπρηη′φ ωJ/ψϒθKBDT