Multidimensional radiative transfer in stratified atmospheres. VI - Radiative instabilities

Bibcode
1990A&A...232..135T
Trujillo Bueno, J.; Kneer, F.
Bibliographical reference

Astronomy and Astrophysics (ISSN 0004-6361), vol. 232, no. 1, June 1990, p. 135-150. Research supported by DGICYT and CICYT.

Advertised on:
6
1990
Number of authors
2
IAC number of authors
1
Citations
13
Refereed citations
10
Description
The possibility that radiative instabilities in stellar atmospheres are driven by transfer of energy processes between stellar gas and the radiation field is considered. Harmonic temperature fluctuations in gray radiative equilibrium atmospheres are introduced, and the linear response of the radiation field to the ensuing Planck-function and opacity fluctuations is investigated. Analytical and numerical calculations are performed, emphasizing the influence of the multidimensional radiative transfer (MRT) effects of opacity fluctuations on the radiative relaxation time as a function of the wavenumber of the perturbations. Quantitative examples are given for stellar atmospheres with solarlike T(eff) and gravitational stratification. It is concluded that, while the MRT effects of B fluctuations generally tend to be stabilizing, the MRT effects of chi fluctuations are optically important for driving radiative instabilities.
Type
Refereed
Radiative transfer
Stellar atmospheres
Stellar oscillations

It may interest you

  • Refereed
    An ultra-short-period super-Earth with an extremely high density and an outer companion
    We present the discovery and characterization of a new multi-planetary system around the Sun-like star K2-360 (EPIC 201595106). K2-360 was first identified in K2 photometry as the host of an ultra-short-period (USP) planet candidate with a period of 0.88 d. We obtained follow-up transit photometry, confirming the star as the host of the signal
    Livingston, John H. et al.

    Advertised on:

    11
    2024
    Bibcode
    2024NatSR..1427219L
    Citations
    0
  • Refereed
    Neural calibration of imaging Stokes polarimeters
    Current polarimetric calibration techniques derive the instrument modulation matrix by numerically fitting an instrumental model to measurements of a set of calibration Stokes vectors. These techniques are typically limited to an error on the retrieved normalized Stokes Q, U and V parameters, in the $1\times10^{-2}$ to $1\times10^{-3}$ range. This
    Iglesias, F. A. et al.

    Advertised on:

    8
    2024
    Bibcode
    2024BAAA...65..281I
    Citations
    0
  • Refereed
    Model-based identification of solar coronal mass ejections using deep neural networks
    Coronal mass ejections (CMEs) are a major driver of space weather and thus can have important negative technological and social impacts. To assess their geoeffectiveness once they are ejected, it is crucial their prompt identification in coronagraph images. In the last decade, deep neural networks (DNN) have experienced enormous improvements in
    Iglesias, F. A. et al.

    Advertised on:

    8
    2024
    Bibcode
    2024BAAA...65...17I
    Citations
    0