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ETC Request ID: ACS.im.2252291

Requested Signal/Noise Ratio = 10.000

gives: Time = 2,758.8400 seconds

gives: Time to Saturation (for a single exposure) = 699,417.37 seconds

gives: Optimum SNR = 18.8396



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Detailed Information Count rate Total counts Associated noise
(e-/s) (e-) (e-)
Counts (circle with radius 0.25 arcsec)
    Source 0.346 954.38 30.89
    Background 1.793 4,946.11 70.33
        Sky 0.367 1,013.11 31.83
        Dark Current 1.426 3,933.00 62.71
        Post Flash 0.00 0.00
    Read Out 56.64
Total in selected region 2.139 5,900.49 95.44
Brightest Pixel (single exposure) 0.111 152.65

Global Count Rates
    Source only 0.402 1,109.684
    Background (sky+dark) 372,006.438 1,026,306,254.31
    Post Flash 0.00

Background per unit area
    Sky Background (arcsec-2) 1.870 5,159.703
    Dark Current (arcsec-2) 7.197 19,856.678
    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: 2
Post Flash: 0 e-


Target: [point source]
Spectrum: Castelli-Kurucz Models B5V 15000 4.0
Extinction E(B-V): None
Normalization: Renormalized to vegamag = 23.37 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