ETC Request ID: STIS.sp.1369096
Exposure time (seconds) = 600.0000 at wavelength 1700.00 Å
gives: SNR = 26.9091 (per resolution element)
Exposure time calculation HAD WARNINGS.
WARNING MESSAGE: MAMA Bright limits: total count rate per image 88530.3 exceeds limit for irregularly-variable sources 40 percent of the bright limit 200000 counts per second
WARNING MESSAGE: Buffer time 22.5911 is less than minimum 99 seconds.
Table of Source and Noise Counts per Pixel
| Detailed Information | Count rate | Total counts | Associated noise |
| (counts/s) | (counts) | (counts) | |
| Counts (box 7 pixels high) | (1 pix x 7 pix) | (2 pix resel x 7 pix) | |
| Source | 0.663 | 795.12 | 28.20 |
| Background | 0.001 | 1.26 | 1.12 |
| Sky | 1.166e-11 | 1.40e-08 | 1.18e-04 |
| Dark Current | 0.001 | 1.26 | 1.12 |
| Total in selected region | 0.664 | 796.38 | 29.55 |
| Brightest Pixel (single exposure) (at 1332.91 Å) | 0.803 | 481.77 | |
| Count rate entire detector | 88,530.251 | ||
| Buffer Time (sec) | 22.59 | ||
| For APT purposes, the recommended buffer time should be 4/5 of the buffer time calculated above. Please refer to the STIS Instrument Handbook for more details. | |||
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| Global Count Rates | |||
| Source only | 53,236.624 | 31,941,974.667 | |
| Background (sky+dark) | 157.418 | 94,450.90 | |
| Encircled energy fraction | 0.94 | ||
| Instrument name: | STIS |
| Mode: | spectroscopic |
| Detector: | FUVMAMA |
| Central Wavelength: | 1425 |
| Grating: | [E140M] R ~ 45800 |
| Aperture: | 0.2X0.2 |
| Glow region: | low |
| Target: [point source] | |
| Spectrum: | Flat in units of Fλ |
| Extinction E(B-V): | None |
| Normalization: | Flux 1.5e-11 flam at 1700.0 Å |
| Redshift: | None |
| Emission Lines: | None |
| Selected background: | |
| Sky Background: | |
| Level: |
Table of Source and Noise Counts per Pixel
These results were computed using: ETC version 27.2
