Space Telescope Imaging Spectrograph Instrument Handbook for Cycle 17

Echelle Line Spread Functions

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Table 13.42: Spectral Resolution for Echelle Medium-Resolution Modes (E230M, E140M)

Slit	Spectral Resolution (FWHM in pixels)
	Point Source				Extended Source
	1200 Å	1500 Å	1700 Å	2400 Å
0.1X0.03	0.9	0.9	1.01,1.62	1.6	~1
0.2X0.2	1.4	1.3	1.11, 2.02	1.9	~6
0.2X0.06	1.3	1.2	1.11, 1.82	1.7	~2
6X0.2	1.6	1.4	1.21, 22	1.9	~6

1FWHM with FUV-MAMA (E140M). 2FWHM with NUV-MAMA (E230M).

Figure 13.91: Echelle Line Spread Functions, E140M (top) and E230M (bottom)


 

Table 13.43: Spectral Resolution for Echelle High Resolution Modes (E140H, E230H)

Slit	Spectral Resolution (FWHM in pixels)
	Point Source				Extended Source
	1200 Å	1500 Å	1700 Å	2400 Å
0.1X0.03	0.8	0.8	11, 1.52	1.5	~1
0.2X0.2	1.3	1.1	11, 1.82	1.7	~6
0.2X0.09	1.2	1.1	11, 1.72	1.7	~2
6X0.2	1.4	1.2	1.21, 22	1.8	~5

1FWHM with FUV-MAMA (E140H). 2FWHM with NUV-MAMA (E230H).

Figure 13.92: Echelle Line Spread Functions, E140H (top) and E230H (bottom). LSFs for E230H were derived using the 0.1X0.2 and 0.1X0.09 apertures, but results for 0.2X0.2 and 0.2X0.09 should be similar.