ETC Request ID: STIS.sp.1464626

Requested Signal/Noise Ratio = 10.000 at wavelength 4900.00 Å (per resolution element)

gives: Time = 85.5077 seconds

gives: Time to Saturation (for a single exposure) = 14,639.43 seconds

Exposure time calculation HAD WARNINGS.

WARNING MESSAGE: "Electrons per pixel due to background (1.2) 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 2.261 386.72 19.67
    Background 0.190 32.47 5.70
        Sky 8.621e-04 0.15 0.38
        Dark Current 0.189 32.32 5.69
    Read Out 32.81
Total in selected region 2.451 419.19 38.67
Brightest Pixel (single exposure) (at 5159.90 Å) 2.254 96.38
Global Count Rates
    Source only 2,137.934 182,809.805
    Background (sky+dark) 28,392.651 2,427,790.03
Encircled energy fraction 0.93

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: Non-stellar Objects QSO (SDSS based) [800, 8554.5 Å z=0]
Extinction E(B-V): Milky Way Diffuse (Rv=3.1) = 0.014 applied before normalization
Normalization: Flux 1e-15 flam at 4900.0 Å
Redshift: z=0.03045
Emission Lines: None


Selected background:
  Sky Background:
    Level:

Table of Source and Noise Counts per Pixel

Plots

These results were computed using: ETC version 28.2