ETC Request ID: STIS.sp.995641

Exposure time (seconds) = 50.0000 at wavelength 4451.00 Å

gives: SNR = 178.4049 (per resolution element)

gives: Time to Saturation (for a single exposure) = 223.60 seconds

Exposure time calculation HAD WARNINGS.

WARNING MESSAGE: "Electrons per pixel due to background (0.47) 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 pix) (2.0 pix resel x pix)
    Source 328.831 32,883.06 181.34
    Background 0.134 13.39 3.66
        Sky 0.008 0.79 0.89
        Dark Current 0.126 12.60 3.55
    Read Out 32.81
Total in selected region 328.964 32,896.44 184.32
Brightest Pixel (single exposure) (at 4025.90 Å) 147.584 3,689.61

Global Count Rates
    Source only 284,717.577 14,235,878.840
    Background (sky+dark) 19,681.341 984,067.04

Encircled energy fraction 0.93


Instrument name: STIS
Mode: spectroscopic
Detector: CCD
Central Wavelength:
Grating: [G430L] R ~ 500
Aperture: 52X2
Gain: 1.0
# Frames: 2
Binning: dispersion: 1, spatial: 1
Dark: medium


Target: [point source]
Spectrum: Standard HST Star Spectra AGK+81°266 (sdO, 11.94) [1148.6, 24955.1 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


Plots

These results were computed using: ETC version 25.1.1