ETC Request ID: STIS.sp.1038637

Exposure time (seconds) = 2.0000 at wavelength 3000.00 Å

gives: SNR = 95.3995 (per resolution element)

gives: Time to Saturation (for a single exposure) = 9.47 seconds

Exposure time calculation HAD WARNINGS.

WARNING MESSAGE: "Electrons per pixel due to background (0.018) 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 2,518.473 10,073.89 100.37
    Background 0.126 0.50 0.71
        Sky 6.932e-07 2.77e-06 1.67e-03
        Dark Current 0.126 0.50 0.71
    Read Out 32.81
Total in selected region 2,518.599 10,074.40 105.60
Brightest Pixel (single exposure) (at 4050.20 Å) 3,486.221 3,486.22
Global Count Rates
    Source only 7,144,211.549 14,288,423.098
    Background (sky+dark) 18,876.106 37,752.21
Encircled energy fraction 0.94

Instrument name: STIS
Mode: spectroscopic
Detector: CCD
Central Wavelength:
Grating: [G430L] R ~ 500
Aperture: 31X0.05NDA
Gain: 1.0
# Frames: 2
Binning: dispersion: 1, spatial: 1
Dark: medium


Target: [point source]
Spectrum: Kurucz Models O5V 44500 5.0
Extinction E(B-V): Milky Way Diffuse (Rv=3.1) = 0.37 applied before normalization
Normalization: Renormalized to vegamag = 5.96 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