STScI Logo

Hubble Space Telescope
COS Spectral Resolution

The tables below provide an optical model of the line spread functions (LSF) and cross-dispersion spread function (CDSF) for COS at various wavelengths, cenwaves, and for different Lifetime Positions. LSFs give the detailed distribution of light along the primary dispersion axis, while CDSFs describe the distribution of light in the cross-dispersion axis.

For more information on COS spectral resolution see section 5.1.4 of the COS IHB, COS ISR 2009-01 and COS ISR 2011-01.

Lifetime Position = 1

Tabulated Theoretical Line Spread Functions
FUV NUV
G130MAll Gratings
G140L 
G160M 

 

Tabulated Theoretical Line Spread Functions With Scattering
FUV NUV
G130M 
G160M 

 

Lifetime Position = 2

Tabulated Theoretical Line Spread Functions
FUV
G130M/1055
G130M/1096
G130M/1222
G130M/1291
G130M/1300
G130M/1309
G130M/1318
G130M/1327
G140L/1105
G140L/1230
G140L/1280
G160M/1577
G160M/1589
G160M/1600
G160M/1611
G160M/1623

 

Tabulated Theoretical Cross-Dispersion Spread Functions
FUV
G130M/1055
G130M/1096
G130M/1222
G130M/1291
G130M/1300
G130M/1309
G130M/1318
G130M/1327
G140L/1105
G140L/1230
G140L/1280
G160M/1577
G160M/1589
G160M/1600
G160M/1611
G160M/1623