ETC Request ID: STIS.sp.1184897
Exposure time (seconds) = 422.0000 at wavelength 2320.00 Å
gives: SNR = 66.8113 (per resolution element)
Exposure time calculation HAD WARNINGS.
WARNING MESSAGE: MAMA Bright limits: total count rate per image 94862.1 exceeds limit for irregularly-variable sources 40 percent of the bright limit 200000 counts per second
WARNING MESSAGE: Buffer time 21.0832 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 | 5.479 | 4,623.88 | 68.00 |
| Background | 0.011 | 8.86 | 2.98 |
| Sky | 7.101e-09 | 5.99e-06 | 2.45e-03 |
| Dark Current | 0.011 | 8.86 | 2.98 |
| Total in selected region | 5.489 | 4,632.74 | 69.21 |
| Brightest Pixel (single exposure) (at 2426.41 Å) | 2.282 | 962.96 | |
| Count rate entire detector | 94,862.119 | ||
| Buffer Time (sec) | 21.08 | ||
| 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 | 75,844.957 | 32,006,571.906 | |
| Background (sky+dark) | 1,572.868 | 663,750.11 | |
| Encircled energy fraction | 0.93 | ||
| Instrument name: | STIS |
| Mode: | spectroscopic |
| Detector: | NUVMAMA |
| Central Wavelength: | 2707 |
| Grating: | [E230M] R ~ 30000 |
| Aperture: | 0.2X0.2 |
| Target: [point source] | |
| Spectrum: | Standard HST Star Spectra BD+28°4211 (Op, 10.51) [1140.6, 10242.7 Å] |
| Extinction E(B-V): | None |
| Normalization: | None |
| 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 26.1
