line profile variability (LPV)
vartandegi-ye farâpâl-e xatt
Fr.: variabilité du profil de raie
The change in the shape of a → spectral line over time. For instance, in → Wolf-Rayet stars the line profile varying on time-scales of minutes to hours is attributed to → microturbulence.
→ line; → profile; → variability.
Fr.: variabilité spectrale
The state of a spectrum from an astronomical object in which the lines change with time as far as their intensity, profile, and wavelength are concerned.
→ spectral; → variability.
The quality, state, or degree of being variable or changeable.
Quality noun from → variable.
Fr.: indice de variabilité
A measure of variability of a star (such as Welch-Stetson variability index) which combines the information from two passbands assuming that changes in the star's luminosity occur nearly simultaneously at all optical wavelengths.
→ variability; → index.