ETC Request ID: STIS.sp.824557
Exposure time (seconds) = 100.0000 at wavelength 2175.00 Å
gives: SNR = 57.2690 (per resolution element)
Exposure time calculation HAD WARNINGS.
WARNING MESSAGE: MAMA Bright limits: total count rate per image 21059 exceeds limit for irregularly-variable sources 40 percent of the bright limit 30000 counts per second
WARNING MESSAGE: Buffer time 94.9711 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 | 16.409 | 3,281.84 | 57.29 |
| Background | 0.011 | 2.10 | 1.45 |
| Sky | 4.467e-06 | 8.93e-04 | 0.03 |
| Dark Current | 0.011 | 2.10 | 1.45 |
| Total in selected region | 16.420 | 3,283.94 | 57.31 |
| Brightest Pixel (single exposure) (at 2569.60 Å) | 10.326 | 1,032.56 | |
| Count rate entire detector | 21,059.038 | ||
| Buffer Time (sec) | 94.97 | ||
| 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 | 19,468.902 | 1,946,890.205 | |
| Background (sky+dark) | 1,590.136 | 159,013.63 | |
| Encircled energy fraction | 0.85 | ||
| Instrument name: | STIS |
| Mode: | spectroscopic |
| Detector: | NUVMAMA |
| Central Wavelength: | |
| Grating: | [G230L] R ~ 500 |
| Aperture: | 52X2 |
| Target: [point source] | |
| Spectrum: | Kurucz Models O5V 44500 5.0 |
| Extinction E(B-V): | Milky Way Diffuse (Rv=3.1) = 0.25 applied before normalization |
| Normalization: | Renormalized to vegamag = 12.8 in filter Johnson/V |
| 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
