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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.

NUV

Tabulated Theoretical Line Spread Functions
NUV
All Gratings

 

FUV Lifetime Position = 1

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

 

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

 

FUV Lifetime Position = 2

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

 

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

 

FUV Lifetime Position = 3

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

 

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

 

FUV Lifetime Position = 4

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

 

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