17,885 research outputs found

    On the Laser Stimulation of Low-Energy Nuclear Reactions in Deuterated Palladium

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    Models to account for the observed experimental results for low-energy nuclear reactions in palladium-deuteride systems are presented along with calculated results. The crucial idea is a mechanism of improved probability for the needed penetration of the Coulomb barrier for a D-D reaction. This facilitation occurs, in general, with the formation of D^- ions at special frequency modes (e.g. via phonons) and, specifically for the laser-stimulated case, with utilization of enhanced optical potential at a selected interface. Both mechanisms may work individually, or together, to increase the probability of barrier penetration.Comment: 9 pages, 3 figures, Rev. 1, Significantly enhanced version (resulting from reviewer's comments), Rev. 2, embedded font and smaller file size. Keywords: CMNS, D--D+, LENR, optical-potential, resonance-enhancemen

    The diurnal heat budget of the thermosphere

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    Detailed numerical calculations of thermospheric heat sources and sinks are presented and their relative importance is discussed in reference to the energy balance phenomena of the neutral atmosphere. It is shown that the thermal energy available from the absorption in the Schumann-Runge continuum leading to photodissociation of O2 is by far the largest energy source in the lower thermosphere. Other sources of varying importance in different altitude ranges are: (1) energy from photoelectrons, (2) energy exchange from thermal plasma, (3) chemical reactions (ion-electron dissociative recombination) energy gain, and (4) kinetic and dissipative energy associated with the neutral wind. The energy sinks of importance are thermal conduction at the lower boundary (120 km) and radiative cooling of atomic oxygen. It is shown that the combined energy from processes 2 to 4 constitute only a small fraction of the total energy available from photoelectrons and are in phase with the latter. It is suggested that a choice of a lower boundary much below 120 km, e.g. near the mesopause level (90 km), should be more appropriate for general thermospheric studies

    Direct photon production from viscous QGP

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    We simulate direct photon production in evolution of viscous QGP medium. Photons from Compton and annihilation processes are considered. Viscous effect on photon production is very strong and reliable simulation is possible only in a limited pTp_T range. For minimally viscous fluid η/s\eta/s=0.08), direct photons can be reliably computed only up to pTp_T \leq 1.3 GeV. With reduced viscosity (η/s\eta/s=0.04), the limit increases to pTp_T \leq 2GeV.Comment: 6 pages, 5 figure
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