F25ND5-FUV-MAMA

Description

The F25ND5 mode with the FUV-MAMA detector provides broad band imaging with an attenuation of 7 x 10-7. The field of view is 25 x 25 arcsec. The R80 and central pixel flux are unmeasured but assumed to be approximately the same as produced by the F25QTZ filter.

Recommended Uses

Recommended for broad-band imaging of objects too bright by about a factor of 10⁶ to meet FUV-MAMA BOP limits.

Special Considerations

At FUV wavelengths the attenuation is closer to a factor of 10⁶ rather than the nominal 10⁵, but the attenuation factor decreases at longer wavelengths, so special care should be taken for red sources. To make an accurate prediction of the expected count rate, observers should use a good approximation of the source spectrum as input for the STIS ETC.

Pivot (Å)	FWHM (Å)	AB mag zeropoint	Speak	B	R80 (arcsec)	Flux in central pixel
1385.1	333.6	8.188	8.81e7	377.2	0.28	10%

Figure 14.74: F25ND5 FUV-MAMA Integrated System Throughput and Redleak

Figure 14.75: Point Source S/N vs. V+AB for the F25ND5 FUV-MAMA mode. Curves are labeled by required exposure time (sec).

Figure 14.76: Extended Source S/N vs. V+AB for the F25ND5 FUV-MAMA mode. Top curves are for an area of 0.2 arcsec2; bottom curves are for 1 arcsec2. Average sky assumed. Curves are labeled by required exposure time (sec).