Astrophysics (Index)About

spectral feature

(recognizable feature of a spectrum)

The term spectral feature is a catch-all for any recognizable feature of a spectrum, ideally providing evidence regarding the characteristics of the source. It might refer to an emission line or absorption line, or the line shape, or a spectral band, or a Balmer jump, or a vegetation red edge. Some lines are common in galaxies and recognizable even when redshifted, offering a means to estimate distance using the Hubble constant.

The term spectral feature extraction is used in discussions of computer techniques aimed at analyzing spectra, allowing and population groupings and examples of specific phenomena to be selected from extensive survey data. Machine learning methods are of interest.

Further reading:

Referenced by pages:
Balmer jump (BJ)
Balmer-break galaxy (BBG)
brightness temperature (TB)
Compton reflection
chemically peculiar star (CP star)
emission line galaxy (ELG)
galaxy age determination
Gunn-Peterson trough
H-alpha (Ha)
Lick indices
non-thermal emission
P Cygni profile
radio galaxy (RG)
spectral class
spectral type
starburst galaxy
stellar atmosphere
stellar temperature determination
telluric star
Thomson optical depth (τT)
vegetation red edge (VRE)
Wien's displacement law
Wolf-Rayet star
Y-type star (Y)