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Title: Forward modeling of gyrosynchrotron intensity perturbations by sausage modes

Abstract

To determine the observable radio signatures of the fast sausage standing wave, we examine gyrosynchrotron (GS) emission modulation using a linear three-dimensional magnetohydrodynamic model of a plasma cylinder. Effects of the line-of-sight angle and instrumental resolution on perturbations of the GS intensity are analyzed for two models: a base model with strong Razin suppression and a low-density model in which the Razin effect was unimportant. Our finding contradicts previous predictions made with simpler models: an in-phase variation of intensity between low (f < f {sub peak}) and high (f > f {sub peak}) frequencies is found for the low-density model and an anti-phase variation for the base model in the case of a viewing angle of 45°. The spatially inhomogeneous character of the oscillating emission source and the spatial resolution of the model are found to have a significant effect on the resulting intensity.

Authors:
;  [1];  [2]
  1. Centre for Mathematical Plasma Astrophysics, Department of Mathematics, KU Leuven, Celestijnenlaan 200B box 2400, B-3001 Leuven (Belgium)
  2. National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan)
Publication Date:
OSTI Identifier:
22357132
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 785; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; DENSITY; DISTURBANCES; EMISSION; FORECASTING; MAGNETOHYDRODYNAMICS; MODULATION; OSCILLATIONS; PERTURBATION THEORY; PLASMA; SIMULATION; SPATIAL RESOLUTION; STANDING WAVES; SUN; THREE-DIMENSIONAL CALCULATIONS

Citation Formats

Reznikova, V. E., Van Doorsselaere, T., and Antolin, P., E-mail: Veronika.Reznikova@wis.kuleuven.be. Forward modeling of gyrosynchrotron intensity perturbations by sausage modes. United States: N. p., 2014. Web. doi:10.1088/0004-637X/785/2/86.
Reznikova, V. E., Van Doorsselaere, T., & Antolin, P., E-mail: Veronika.Reznikova@wis.kuleuven.be. Forward modeling of gyrosynchrotron intensity perturbations by sausage modes. United States. doi:10.1088/0004-637X/785/2/86.
Reznikova, V. E., Van Doorsselaere, T., and Antolin, P., E-mail: Veronika.Reznikova@wis.kuleuven.be. Sun . "Forward modeling of gyrosynchrotron intensity perturbations by sausage modes". United States. doi:10.1088/0004-637X/785/2/86.
@article{osti_22357132,
title = {Forward modeling of gyrosynchrotron intensity perturbations by sausage modes},
author = {Reznikova, V. E. and Van Doorsselaere, T. and Antolin, P., E-mail: Veronika.Reznikova@wis.kuleuven.be},
abstractNote = {To determine the observable radio signatures of the fast sausage standing wave, we examine gyrosynchrotron (GS) emission modulation using a linear three-dimensional magnetohydrodynamic model of a plasma cylinder. Effects of the line-of-sight angle and instrumental resolution on perturbations of the GS intensity are analyzed for two models: a base model with strong Razin suppression and a low-density model in which the Razin effect was unimportant. Our finding contradicts previous predictions made with simpler models: an in-phase variation of intensity between low (f < f {sub peak}) and high (f > f {sub peak}) frequencies is found for the low-density model and an anti-phase variation for the base model in the case of a viewing angle of 45°. The spatially inhomogeneous character of the oscillating emission source and the spatial resolution of the model are found to have a significant effect on the resulting intensity.},
doi = {10.1088/0004-637X/785/2/86},
journal = {Astrophysical Journal},
number = 2,
volume = 785,
place = {United States},
year = {Sun Apr 20 00:00:00 EDT 2014},
month = {Sun Apr 20 00:00:00 EDT 2014}
}
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