The spectral resolution of a spectrograph, or, more generally, of a frequency spectrum, is a measure of its ability to resolve features in the electromagnetic spectrum. It is usually denoted by, and is closely related to the resolving power of the spectrograph, defined as
,
where is the smallest difference in wavelengths that can be distinguished at a wavelength of . For example, the Space Telescope Imaging Spectrograph (STIS) can distinguish features 0.17 nm apart at a wavelength of 1000 nm, giving it a resolution of 0.17 nm and a resolving power of about 5,900. An example of a high resolution spectrograph is the Cryogenic High-Resolution IR Echelle Spectrograph (CRIRES) installed at ESO's Very Large Telescope, which has a spectral resolving power of up to 100,000.
Read more about Spectral Resolution: Doppler Effect, IUPAC Definition, See Also
Famous quotes containing the words spectral and/or resolution:
“How does one kill fear, I wonder? How do you shoot a spectre through the heart, slash off its spectral head, take it by its spectral throat?”
—Joseph Conrad (1857–1924)
“We often see malefactors, when they are led to execution, put on resolution and a contempt of death which, in truth, is nothing else but fearing to look it in the face—so that this pretended bravery may very truly be said to do the same good office to their mind that the blindfold does to their eyes.”
—François, Duc De La Rochefoucauld (1613–1680)