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Showing 1 to 19 of 19 for “"He3"”.
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Diffusion of He3 in superfluid background.
Massachusetts Institute of Technology. Dept. of Physics. Thesis. 1971. Ph.D.
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He3-induced reactions in Li6 and Li7
Li6 and Li7 targets were bombarded by He3 particles at 21.2, 24.5, and 26.8 MeV. A solid-state-detector telescope detected He3 and et particles, plus some tritons, coming from the target. The forms of the angular distributions were characteristie of direct interaction processes. ... Each reaction …
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Propagation of zero sound in liquid He3
The propagation of sound in liquid He3 was observed at a pressure of 0.32 atm and at fre~quencies of 15.4 and 45.5 MHz down to a temperao 0 -3 0 . ture T* of 2m K (1m K = 10 K) on the temperature scale va11d for the Curie-law magnetic susceptibility of powdered cerium magnesium nitrate in the form …
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Photoproduction of pi�� mesons from He3 with 340 MeV bremsstrahlung
… coherent photoproduction of 71""0 mesons from He3(gammaHe3 -> pi°He 3) were measured for recoil angles of 200, 300, 400, and 500 from the direction of the incident photon. A gaseous He3 target was irradiated by 340 MeV bremsstrahlung; provided by the 'University of Illinois betatron. The He3 …
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Phonon-quasiparticle interactions in dilute solutions of He3 in superfluid He4
… interactions in dilute solutions of He3 in superfluid He4 and the role they play in determining the linear response prQperties of such solutions are examined. The vertices for phonon scattering and absorption by He3 quasiparticles as well as the effective interaction between …
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Experimental study of the reaction He3 ([v], [pi+])H3 up to 260 MeV
"The differential cross section for the, reaction He3(y,n+)H3 was measured for photon energies of 180 to/260 MeV (momentum transfer 1.2 F-1 to 1.9 F-1). A target of gaseous He at 20.4 K and approximately one atmosphere preesure was irradiated by a 270 MeV bremsstrahlung x-ray beam. The reaction was …
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Magnetic properties of dilute solutions of liquid He³ in He⁴ at low temperatures
… magnetic susceptibility of dilute solutions of He3 in He4 has been measured down to about 3moK. These measurements were made on two solutions of nominal concentrations of 1.3 and 5.0% He3 in He4 under their own vapor pressures. The values of the diffusion coefficient fit T*-2 laws below about …
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Design of Resistivity Instrumentation for a He3 Cryostat and its Application to the Charge Density Wave Superconductor CuxTiSe2
… implemented utilizing an Infrared Labs HDL-10 He3 cryostat. By comparing with data from the literature, doping of two samples was investigated using the new measurement system and a Quantum Design Magnetic Property Measurement System (MPMS). Methods for determining the doping revealed that the …
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Study of the Bi209 (gamma,pi-xn) Po209-x and Pb206 (He3,xn) Po209-x reactions by detection of polonium alpha activities
The cross sections for Bi 209{gamma, pi-xn ) Po209-x were measured for x = 0-3, 5, and 7 and used to estimate the total (gamma, pi-) cross section. Total (gamma, pi-) cross sections have not previously been measured for a complex nucleus. At bremsstrahlung energies of 200,220, and 250 MeV, the …
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Heat capacity of dilute solutions of liquid He[superscript 3] in He[superscript 4] at low temperatures
… were made on two dilute solutions of 1iquid He3 in He4. These data, taken under saturated vapor o 0 pressure at temperatures between .005 K and .20 K, are characteristic of an ideal Fermi gas with m'l'< dependent only slightly on concentration. The solution with a molar concentration of Re3 …
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Application of compressional cooling to the study of nuclear ordering in solid helium three
"A powerful cooling technique for He3 has been used to observe ordering of the nuclear spins in solid He3 He3 atoms in the solid are localized at lattice sites. Interactions between neighboring atoms, due to zero point motion, are relatively small until temperatures in the low I millidegree Kelvin …
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Modeling the Non-equilibrium Phenomenon of Diffusion in Closed and Open Systems at an Atomistic Level Using Steepest-Entropy-Ascent Quantum Thermodynamics
… model for an isolated system in which He3 diffuses in He4. The model developed is able to predict the non-equilibrium and equilibrium characteristics of diffusion as well as capture the differences in behavior of fermions (He3) and bosons (He4). The SEAQT framework is also used to …
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Interstellar Mission Design of a Fusion-Powered Spacecraft to Proxima b
… and analyzes its performance for 4 fuels: D-D, D-He3, D-T, and p-B11. Additionally, the system performance was examined for a fast and slow flyby of Proxima b, and bounded orbit. The analysis indicated a slow flyby and bounded orbit are most ideal for data collection, and can only be supported by …
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Differential cross sections for the reaction He[superscript 3] ([gamma],[rho]) H[superscript 2] from 45 to 150 MeV
… for photon energies down to 40 MeV. A gaseous He3 target at about 4°K and slightly less than one atmosphere pressure was bombarded with 250 MeV bremsstrahlung. The deuteron detection system, which was a telescope of three semiconductor detectors followed by a plastic scintillator, actually …
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A Bf3 Fast Neutron Dosimeter (Long Counter)
… and the induced reactions H2(d,n)He3 and H3(d,n)He4. Long counter efficiencies for both a 1 inch and 1/2 inch BF) tube yield a flat response over the energy range, 2.5 to 4 Mev whereas an approximately 60% decrease in efficiency is observed for a 14.1 Mev neutron. Count rate of …
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Thermal conductivity of liquid helium three
… have measured the thermal conductivity of liquid He3 at low pressure from O. 055 0 K to O. 47 o K, at 99.8 psi from O. 0550 K to O. 750 K and at 396.8 psi from O. 0550 K to O. 87 o K. At all pressures and at sufficiently low temperatures the thermal conductivity increases with decreasing …
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Supercurrents in Restricted Geometries and Driven by Time-Dependent Electric Fields
… to be consistent in leading order. Weak links in He3 We investigated several methods of calculating the current-phase relation of weak links in He3. In the limit of small holes the hole itself and the current through it does not affect the order parameter in the superfluid and the current can …
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Photoproduction of neutral pions in helium by 335 MEV Bremsstrahlung
… of the He recoils from the background of He3 recoilS and a11owed'a better identification of the coherent He4 events that had been achieved in earlier experiments. The laboratory cross sections were found to vary from 40 ub/sr at 200 and 230 MeV photon energy decreasing with energy to 55 …
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Collimation of deuterium / 3-helium fusion products for advanced spacecraft propulsion and power
… In this class it is well accepted that d-He3 fusion is the most promising of the fuel candidates for spacecraft applications as the 14.7 MeV protons carry up to 80% of the total fusion power while ‘s have energies less than 4 MeV. The other minor fusion products from secondary d-d …