ETC Request ID: STIS.sp.1010633

Exposure time (seconds) = 100.0000 at wavelength 3500.00 Å

gives: SNR = 24.1519 (per resolution element)

gives: Time to Saturation (for a single exposure) = 272.78 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: "Electrons per pixel due to background (0.9) is less than the recommended threshold of 20 electrons to avoid poor charge transfer efficiency (CTE). We suggest you consider CTE mitigation strategies described in the STIS Instrument Handbook."


Table of Source and Noise Counts per Pixel


Plots


Detailed Information Count rate Total counts Associated noise
(e-/s) (e-) (e-)
Counts (box 7 pixels high) (1 pix x 7 pix) (2 pix resel x 7 pix)
    Source 5.723 1,144.66 33.83
    Background 0.126 25.23 5.02
        Sky 1.309e-04 0.03 0.16
        Dark Current 0.126 25.20 5.02
    Read Out 32.81
Total in selected region 5.849 1,169.88 47.39
Brightest Pixel (single exposure) (at 4860.20 Å) 120.977 6,048.84

Global Count Rates
    Source only 47,372.301 4,737,230.075
    Background (sky+dark) 18,955.825 1,895,582.48

Encircled energy fraction 0.94


Instrument name: STIS
Mode: spectroscopic
Detector: CCD
Central Wavelength:
Grating: [G430L] R ~ 500
Aperture: 52X0.2
Gain: 1.0
# Frames: 2
Binning: dispersion: 1, spatial: 1
Dark: medium


Target: [point source]
Spectrum: User uploaded spectrum: tcha_13_cos.dat
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 25.2