ETC Request ID: STIS.sp.827625

Exposure time (seconds) = 1.0000 at wavelength 2400.00 Å

gives: SNR = 34.7015 (per resolution element)

gives: Time to Saturation (for a single exposure) = 58.96 seconds

Exposure time calculation HAD WARNINGS.

WARNING MESSAGE: "Electrons per pixel due to background (0.0095) 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 945.046 1,890.09 43.48
    Background 0.133 0.27 0.52
        Sky 3.205e-08 6.41e-08 2.53e-04
        Dark Current 0.133 0.27 0.52
    Read Out 32.81
Total in selected region 945.179 1,890.36 54.47
Brightest Pixel (single exposure) (at 2420.30 Å) 559.709 279.85

Global Count Rates
    Source only 1,041,083.450 1,041,083.450
    Background (sky+dark) 19,922.945 19,922.95

Encircled energy fraction 0.95


Instrument name: STIS
Mode: spectroscopic
Detector: CCD
Central Wavelength:
Grating: [G230LB] R ~ 700
Aperture: 0.1X0.03
Gain: 1.0
# Frames: 2
Binning: dispersion: 1, spatial: 1
Dark:


Target: [point source]
Spectrum: Bruzual Synthetic Stellar Spectra O8 V
Extinction E(B-V): None
Normalization: Flux 3.8e-11 flam at 2025.0 Å
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