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ETC Request ID: ACS.im.2252187

Requested Signal/Noise Ratio = 10.000

gives: Time = 1,435.6206 seconds

gives: Time to Saturation (for a single exposure) = 527,986.08 seconds

gives: Optimum SNR = 18.0608



Plots


Detailed Information Count rate Total counts Associated noise
(e-/s) (e-) (e-)
Counts (circle with radius 0.25 arcsec)
    Source 0.486 698.29 26.43
    Background 1.793 2,573.81 50.73
        Sky 0.367 527.19 22.96
        Dark Current 1.426 2,046.62 45.24
        Post Flash 0.00 0.00
    Read Out 40.05
Total in selected region 2.279 3,272.10 69.83
Brightest Pixel (single exposure) 0.147 210.45

Global Count Rates
    Source only 0.566 811.918
    Background (sky+dark) 372,006.438 534,060,111.00
    Post Flash 0.00

Background per unit area
    Sky Background (arcsec-2) 1.870 2,684.960
    Dark Current (arcsec-2) 7.197 10,332.841
    Post Flash (arcsec-2) 0.00

Extraction region
circle with radius 0.25 arcsec
    Effective Sky Area (pixels) 80.30
    Fraction of flux 0.86
    Fraction of flux in brightest pixel 0.22
Effective Wavelength 6584.67 Å


Instrument name: ACS
Mode: imaging
Detector: WFC
Coronography: off
Bandpass: [F658N] H alpha (1%)
Gain: 2.0
# Frames: 1
Post Flash: 0 e-


Target: [point source]
Spectrum: Castelli-Kurucz Models B5V 15000 4.0
Extinction E(B-V): None
Normalization: Renormalized to vegamag = 23.0 in filter Johnson/V
Redshift: None
Emission Lines: None


Selected background:
  Sky Background: component
    Earth Shine: Average
    Zodiacal Light: Average
    Air Glow: Average


Plots

These results were computed using: ETC version 34.1