ETC Request ID: STIS.sp.825893

Requested Signal/Noise Ratio = 20.000 at wavelength 1500.00 Å (per resolution element)

gives: Time = 309.2218 seconds

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.

WARNING MESSAGE: Buffer time 36.5591 is less than minimum 99 seconds.


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 pix) (2.0 pix resel x pix)
    Source 0.729 451.10 21.24
    Background 0.001 0.65 0.81
        Sky 3.485e-14 2.15e-11 4.64e-06
        Dark Current 0.001 0.65 0.81
Total in selected region 0.730 451.75 22.56
Brightest Pixel (single exposure) (at 1274.92 Å) 0.600 185.67
Count rate entire detector 54,705.927
Buffer Time (sec) 36.56
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 32,860.485 10,161,177.521
    Background (sky+dark) 157.420 48,677.78
Encircled energy fraction 0.95

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: User uploaded spectrum: combined.txt
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

Plots

These results were computed using: ETC version 24.2