ETC Request ID: STIS.sp.827930
Exposure time (seconds) = 250.0000 at wavelength 1854.00 Å
gives: SNR = 21.6913 (per resolution element)
Exposure time calculation HAD WARNINGS.
WARNING MESSAGE: Buffer time 37.4121 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 pix) | (2.0 pix resel x pix) | |
| Source | 1.050 | 525.15 | 22.92 |
| Background | 0.011 | 5.25 | 2.29 |
| Sky | 1.634e-12 | 8.17e-10 | 2.86e-05 |
| Dark Current | 0.011 | 5.25 | 2.29 |
| Total in selected region | 1.061 | 530.40 | 24.21 |
| Brightest Pixel (single exposure) (at 1929.40 Å) | 0.477 | 119.32 | |
| Count rate entire detector | 53,458.667 | ||
| Buffer Time (sec) | 37.41 | ||
| 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 | 33,539.414 | 8,384,853.594 | |
| Background (sky+dark) | 1,572.864 | 393,216.00 | |
| Encircled energy fraction | 0.92 | ||
| Instrument name: | STIS |
| Mode: | spectroscopic |
| Detector: | NUVMAMA |
| Central Wavelength: | 1813 |
| Grating: | [E230H] R ~ 114000 |
| Aperture: | 0.1X0.03 |
| Target: [point source] | |
| Spectrum: | Bruzual Synthetic Stellar Spectra O8 V |
| Extinction E(B-V): | None |
| Normalization: | Flux 3.8e-11 flam at 2026.0 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 24.2
