Results 11 to 20 of about 39,482 (251)
Turbulent Diffusion in the Photosphere as Derived from Photospheric Bright Point Motion
The Astrophysical Journal, 2011 On the basis of observations of solar granulation obtained with the New Solar Telescope (NST) of Big Bear Solar Observatory, we explored proper motion of bright points (BPs) in a quiet sun area, a coronal hole, and an active region plage. We automatically detected and traced bright points (BPs) and derived their mean-squared displacements as a function
V. I. Abramenko +7 more
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Photospheric magnetoconvection [PDF]
Proceedings of the International Astronomical Union, 2006 AbstractMagnetic fields, convective motions and radiative energy transport all strongly influence each other in the solar photosphere. Attempts to understand, at a quantitative level, the diverse phenomona seen in the photosphere have relied on increasingly powerful computers since the 1980's.
Cameron, R., Schüssler, M., Vögler, A.
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Flare-induced Photospheric Velocity Diagnostics [PDF]
The Astrophysical Journal, 2021 Abstract We present radiative-hydrodynamic simulations of solar flares generated by the RADYN and RH codes to study the perturbations induced in photospheric Fe i lines by electron beam heating. We investigate how variations in the beam parameters result in discernible differences in the induced photospheric velocities.
Aaron J. Monson +4 more
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Symposium - International Astronomical Union, 1987 The temperature stratifications and the emitted fluxes of Mira model photospheres based upon the extended density distribution of a pulsation model differ substantially from those of conventional model photospheres based upon a hydrostatic density distribution.
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Photospheres of Mira variables [PDF]
International Astronomical Union Colloquium, 1988 Mira variables form an important subgroup of the red giant stars which are typical representatives of stars showing burnt material at their surfaces. Since the photospheres of Miras are not in hydrostatic equilibrium but are characterized by spherically very extended density stratifications, their properties and emitted spectra differ substantially ...
M.S. Bessell +5 more
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Solar Physics From Unconventional Viewpoints
Frontiers in Astronomy and Space Sciences, 2018 We explore new opportunities for solar physics that could be realized by future missions providing sustained observations from vantage points away from the Sun-Earth line.
Sarah E. Gibson +8 more
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Recent Results for Widths of Lines Important in the Spectra of Cool Stars
Open Astronomy, 2011 The broadening of spectral lines by neutral perturbers is an important factor in the interpretation of the observed spectra of cool stars and is often included in the analysis by using a simple van der Waals formula. Detailed calculations are carried out
Peach G.
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HXR photospheric footprints [PDF]
Proceedings of the International Astronomical Union, 2007 AbstractWe have analysed the 6 mHz egression power signatures of some accoustically active X-class solar flares. During the impulsive phase these flares produced conspicuous seismic signatures which have kernel-like structures, mostly aligned with the neutral line of the host active region.
J. C. Martínez-Oliveros +2 more
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The close circumstellar environment of Betelgeuse - Adaptive optics spectro-imaging in the near-IR with VLT/NACO [PDF]
, 2009 Context: Betelgeuse is one the largest stars in the sky in terms of angular diameter. Structures on the stellar photosphere have been detected in the visible and near-infrared as well as a compact molecular environment called the MOLsphere.
Baldwin +43 more
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Equation of state for solar near-surface convection [PDF]
Annales Geophysicae, 2015 Numerical 3-D radiative hydrodynamical simulations are the main tool for the analysis of the interface between the solar convection zone and the photosphere. The equation of state is one of the necessary ingredients of these simulations.
N. Vitas +4 more
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