Search Results - "Vorontsov, S. V."

Effects of differential rotation and meridional circulation in solar oscillations of high degree l by Vorontsov, S. V.

“…Helioseismic measurements at high degree l are sensitive to mode couplings induced by large-scale flows, with the largest contribution coming from the solar…”
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Helioseismic Measurement of Solar Torsional Oscillations by Vorontsov, S V, Christensen-Dalsgaard, J, Schou, J, Strakhov, V N, Thompson, MJ

“…Bands of slower and faster rotation, the so-called torsional oscillations, are observed at the Sun's surface to migrate in latitude over the 11-year solar…”
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Acoustic wave reflection by stellar cores: can it be seen in the autocorrelation function of p-mode measurements? by Roxburgh, I. W., Vorontsov, S. V.

“…The rapid variation of density with depth in a stellar core can distort acoustic wave propagation in stellar interiors, producing a reflected wave. The…”
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Helioseismic calibration of the equation of state and chemical composition in the solar convective envelope by Vorontsov, S. V., Baturin, V. A., Ayukov, S. V., Gryaznov, V. K.

“…Accurate and precise measurements of solar p-mode frequencies allow sensitive diagnostics of the adiabatic exponent Γ1 = (∂ln p/∂ln ρ) S as a function of depth…”
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Helioseismic measurements in the solar envelope using group velocities of surface waves by Vorontsov, S. V., Baturin, V. A., Ayukov, S. V., Gryaznov, V. K.

“…At intermediate- and high-degree l, solar p and f modes can be considered as surface waves. Using variational principle, we derive an integral expression for…”
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Semiclassical approximation for low-degree stellar p modes — III. Acoustic resonances and diagnostic properties of the oscillation frequencies by Roxburgh, I. W., Vorontsov, S. V.

“…We extend the classical approximation for low-degree acoustic oscillations to take account of the effects of wave resonances associated with the partial…”
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Semiclassical approximation for low-degree stellar p modes - I. The classical eigenfrequency equation by Roxburgh, I. W., Vorontsov, S. V.

“…A new eigenfrequency equation for low-degree solar-like oscillations in stars is developed, based on the assumption of purely classical propagation in the…”
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Solar p modes of high degree l: coupling by differential rotation by Vorontsov, S. V.

“…Accurate measurements of solar p-mode frequencies and frequency splittings at high degree l require an adequate theoretical knowledge of the effects of mode…”
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Neutron Physics Experiments at the BIGR and BIR-2M Pulsed Reactors by Vorontsov, S. V., Kuvshinov, M. I., Sibgatullin, I. Z.

“…While the primary purpose of the BIR and BIGR reactors is to generate neutron and gamma irradiation pulses, they were also used regularly to conduct…”
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The Seismic Structure of the Sun by Gough, D. O., Kosovichev, A. G., Toomre, J., Anderson, E., Antia, H. M., Basu, S., Chaboyer, B., Chitre, S. M., Christensen-Dalsgaard, J., Dziembowski, W. A., Eff-Darwich, A., Elliott, J. R., Giles, P. M., Goode, P. R., Guzik, J. A., Harvey, J. W., Hill, F., Leibacher, J. W., M. J. P. F. G. Monteiro, Richard, O., Sekii, T., Shibahashi, H., Takata, M., Thompson, M. J., Vauclair, S., Vorontsov, S. V.

“…Global Oscillation Network Group data reveal that the internal structure of the sun can be well represented by a calibrated standard model. However,…”
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Deconvolution of astronomical images using SOR with adaptive relaxation by Vorontsov, S V, Strakhov, V N, Jefferies, S M, Borelli, K J

“…We address the potential performance of the successive overrelaxation technique (SOR) in image deconvolution, focusing our attention on the restoration of…”
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The autocorrelation function of stellar p-mode measurements and its diagnostic properties by Roxburgh, I. W., Vorontsov, S. V.

“…The basic properties of acoustic wave propagation in stellar interiors can be analysed from the autocorrelation function (ACF) of intensity (or velocity)…”
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Seismology of the solar envelope: sound-speed gradient in the convection zone and its diagnosis of the equation of state by Baturin, V. A., Däppen, W., Gough, D. O., Vorontsov, S. V.

“…We report the results of an asymptotic inversion of solar oscillation data for the gradient of the sound speed in the convection zone. This gradient reveals…”
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Semiclassical approximation for low-degree stellar p modes - II. Classical ray tracing by Roxburgh, I. W., Vorontsov, S. V.

“…Using ray-tracing techniques, we consider nearly forward refraction in the stellar interior of acoustic waves modified by buoyancy and gravity. Our analysis is…”
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Seismology of the solar envelope: measuring the acoustic phase shift generated in the outer layers by Gough, D. O., Vorontsov, S. V.

“…Partial reflection of acoustic waves by regions of rapid spatial variation modulates the solar p-mode frequencies, in a manner that is often described in terms…”
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Planned Destruction of Metal-Core Reactor: Simulation of Catastrophic Accidents and New Experimental Possibilities by Vorontsov, S. V., Kuvshinov, M. I., Narozhnyi, A. T., Popov, V. A., Solov’ev, V. P., Yuferev, V. I.

“…A reactor with a destructible core (RIR reactor) generating a pulse with an output of ~1.5 × 10 19 fissions and a full width at half maximum of ~2.5 μs was…”
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Seismology of the solar envelope: the base of the convective zone as seen in the phase shift of acoustic waves by Roxburgh, Ian W., Vorontsov, Sergei V.

“…At the base of the convective zone, discontinuities in the derivatives of the sound speed produce a phase shift in acoustic waves. This phase shift, α0(ν), is…”
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Studies of the High-Intensity Field of Intermediate Neutrons of a BR-K1 Reactor by Sevast’yanov, V. D., Kovalenko, O. I., Shibaev, R. M., Koshelev, A. S., Vorontsov, S. V., Drozdov, I. Yu

“…A new high-intensity source of intermediate neutrons in the center of the active zone of a powerful pulsed BRK1 reactor has been created. Measurement of the…”
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The seismology of stellar cores: a simple theoretical description of the ‘small frequency separations’ by Roxburgh, I. W., Vorontsov, S. V.

“…We present a new theoretical description of the ‘small frequency separations’ $\delta\omega_{l,n} = \omega_{l,n} - \omega_{l+2,n-1}$ for high-frequency stellar…”
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An asymptotic description of solar acoustic oscillations with an elementary excitation source by Roxburgh, I. W., Vorontsov, S. V.

“…We extend the asymptotic description of solar p-modes to include an excitation source. The linear dynamic response of a star is considered within the general…”
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