ETC Request ID: STIS.sp.824396

Requested Signal/Noise Ratio = 100.000 at wavelength 5500.00 Å (per resolution element)

gives: Time = 1.5529 seconds

gives: Time to Saturation (for a single exposure) = 14.80 seconds

Exposure time calculation HAD WARNINGS.

WARNING MESSAGE: "Electrons per pixel due to background (0.015) 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 3,535.611 10,980.58 104.79
    Background 0.134 0.41 0.64
        Sky 5.526e-04 1.72e-03 0.04
        Dark Current 0.133 0.41 0.64
    Read Out 32.81
Total in selected region 3,535.744 10,981.00 109.81
Brightest Pixel (single exposure) (at 6456.10 Å) 2,229.798 1,731.28

Global Count Rates
    Source only 3,676,443.133 5,708,982.435
    Background (sky+dark) 19,994.409 31,048.41

Encircled energy fraction 0.93


Instrument name: STIS
Mode: spectroscopic
Detector: CCD
Central Wavelength:
Grating: [G750L] R ~ 500
Aperture: 52X0.1
Gain: 1.0
# Frames: 2
Binning: dispersion: 1, spatial: 1
Dark:


Target: [point source]
Spectrum: Bruzual Synthetic Stellar Spectra B0 I
Extinction E(B-V): Milky Way Diffuse (Rv=3.1) = 1.01 applied before normalization
Normalization: Renormalized to vegamag = 8.5 in filter Johnson/V
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