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ETC Request ID: ACS.im.2252228

Requested Signal/Noise Ratio = 10.000

gives: Time = 3,039.9173 seconds

gives: Time to Saturation (for a single exposure) = 1,448,681.46 seconds



Plots


Detailed Information Count rate Total counts Associated noise
(e-/s) (e-) (e-)
Counts (circle with radius 0.25 arcsec)
    Source 0.459 1,396.25 37.37
    Background 3.843 11,682.87 108.09
        Sky 2.418 7,349.16 85.73
        Dark Current 1.426 4,333.71 65.83
        Post Flash 0.00 0.00
    Read Out 80.10
Total in selected region 4.302 13,079.12 139.62
Brightest Pixel (single exposure) 0.053 40.60

Global Count Rates
    Source only 117.582 357,439.901
    Background (sky+dark) 800,403.887 2,433,161,647.71
    Post Flash 0.00

Background per unit area
    Sky Background (arcsec-2) 12.313 37,428.985
    Dark Current (arcsec-2) 7.197 21,879.725
    Post Flash (arcsec-2) 0.00

Extraction region
circle with radius 0.25 arcsec
    Effective Sky Area (pixels) 80.30
Effective Wavelength 4468.34 Å


Instrument name: ACS
Mode: imaging
Detector: WFC
Coronography: off
Bandpass: [F435W] Johnson B
Gain: 2.0
# Frames: 4
Post Flash: 0 e-


Target: [extended source]
Source diameter (arcsec): 8.0
Spectrum: Non-stellar Objects Spiral Galaxy
Extinction E(B-V): None
Normalization: Renormalized to flam = 7.5e-19 in filter ACS/WFC1/F435W
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