ETC Request ID: STIS.sp.1012240

Requested Signal/Noise Ratio = 40.000 at wavelength 2026.00 Å (per resolution element)

gives: Time = 6.2079 seconds

gives: Time to Saturation (for a single exposure) = 151.64 seconds

Exposure time calculation HAD WARNINGS.

WARNING MESSAGE: "Electrons per pixel due to background (0.11) 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 182.495 2,265.84 47.60
    Background 0.126 1.56 1.25
        Sky 4.624e-10 5.74e-09 7.58e-05
        Dark Current 0.126 1.56 1.25
    Read Out 30.68
Total in selected region 182.621 2,267.40 56.65
Brightest Pixel (single exposure) (at 3065.10 Å) 791.350 4,912.66
Global Count Rates
    Source only 939,477.890 5,832,228.305
    Background (sky+dark) 18,874.394 117,171.23
Encircled energy fraction 0.93

Instrument name: STIS
Mode: spectroscopic
Detector: CCD
Central Wavelength:
Grating: [G230LB] R ~ 700
Aperture: 31X0.05NDC
Gain: 4.0
# Frames: 1
Binning: dispersion: 1, spatial: 1
Dark: medium


Target: [point source]
Spectrum: Castelli-Kurucz Models B0III 29000 3.5
Extinction E(B-V): Milky Way Diffuse (Rv=3.1) = 0.26 applied before normalization
Normalization: Renormalized to vegamag = 4.96 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 25.2