EXCITATION OF ACOUSTIC WAVES BY VORTICES IN THE QUIET SUN

Journal Article · Tue Feb 01 00:00:00 EST 2011 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/727/2/L50· OSTI ID:21560531

Kitiashvili, I N; Kosovichev, A G ^[1]; Mansour, N N

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1. W.W. Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305 (United States)

The five-minute oscillations are one of the basic properties of solar convection. Observations show a mixture of a large number of acoustic wave fronts propagating from their sources. We investigate the process of acoustic waves excitation from the point of view of individual events, by using a realistic three-dimensional radiative hydrodynamic simulation of the quiet Sun. The results show that the excitation events are related to the dynamics of vortex tubes (or swirls) in intergranular lanes of solar convection. These whirlpool-like flows are characterized by very strong horizontal velocities (7-11 km s{sup -1}) and downflows ({approx}7 km s{sup -1}), and are accompanied by strong decreases of temperature, density, and pressure at the surface and 0.5-1 Mm below the surface. High-speed whirlpool flows can attract and capture other vortices. According to our simulation results the processes of vortex interaction, such as vortex annihilation, can cause excitation of acoustic waves on the Sun.

• OSTI ID: 21560531
• Journal Information: Astrophysical Journal Letters, Vol. 727, Issue 2; Other Information: DOI: 10.1088/2041-8205/727/2/L50; ISSN 2041-8205
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
CONVECTION
EXCITATION
OSCILLATIONS
SIMULATION
SOUND WAVES
SUN
THREE-DIMENSIONAL CALCULATIONS
VORTICES
ENERGY TRANSFER
ENERGY-LEVEL TRANSITIONS
HEAT TRANSFER
MAIN SEQUENCE STARS
MASS TRANSFER
STARS