ETC Request ID: STIS.sp.1014899

Exposure time (seconds) = 3,093.0000 at wavelength 1215.67 Å

gives: SNR = 0.0012 (per resolution element)

Exposure time calculation HAD WARNINGS.

WARNING MESSAGE: Partial overlap between instrument throughput band and target spectrum. Please doublecheck the wavelength range covered by the selected spectrum, and the instrument documentation for the selected filter.


Table of Source and Noise Counts per Pixel

Plots

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 8.870e-07 5.49e-03 0.07
    Background 0.004 22.55 4.75
        Sky 0.003 16.05 4.01
        Dark Current 0.001 6.50 2.55
Total in selected region 0.004 22.56 4.75
Brightest Pixel (single exposure) (at 1216.66 Å) 0.012 35.69
Count rate entire detector 159.860
Buffer Time (sec) 12,510.95
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.
Global Count Rates
    Source only 1.526 4,721.258
    Background (sky+dark) 157.326 486,609.42
Encircled energy fraction 0.88

Instrument name: STIS
Mode: spectroscopic
Detector: FUVMAMA
Central Wavelength: 1425
Grating: [E140M] R ~ 45800
Aperture: 0.2X0.06
Glow region: low


Target: [point source]
Spectrum: User uploaded spectrum: Kapteyn_LyA.txt
Extinction E(B-V): None
Normalization: None
Redshift: None
Emission Lines: None


Selected background:
  Sky Background:
    Earth Shine: Average
    Zodiacal Light: Average
    Air Glow: Average

Table of Source and Noise Counts per Pixel

Plots

These results were computed using: ETC version 25.2