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ETC Request ID: ACS.im.2252295

Exposure time (seconds) = 3,040.0000

gives: SNR = 5.1587

gives: Time to Saturation (for a single exposure) = 1,529,463.64 seconds


Plots

Detailed Information Count rate Total counts Associated noise
(e-/s) (e-) (e-)
Counts (circle with radius 0.25 arcsec)
    Source 0.233 707.45 26.60
    Background 3.843 11,683.19 108.09
        Sky 2.418 7,349.36 85.73
        Dark Current 1.426 4,333.82 65.83
        Post Flash 0.00 0.00
    Read Out 80.10
Total in selected region 4.076 12,390.64 137.14
Brightest Pixel (single exposure) 0.051 38.46
Global Count Rates
    Source only 59.575 181,107.808
    Background (sky+dark) 800,403.887 2,433,227,815.95
    Post Flash 0.00
Background per unit area
    Sky Background (arcsec-2) 12.313 37,430.003
    Dark Current (arcsec-2) 7.197 21,880.320
    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 = 3.8e-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