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ETC Request ID: ACS.im.2252290

Exposure time (seconds) = 1,742.0000

gives: SNR = 6.7482

gives: Time to Saturation (for a single exposure) = 674,016.68 seconds

gives: Optimum SNR = 13.2171


Plots

Detailed Information Count rate Total counts Associated noise
(e-/s) (e-) (e-)
Counts (circle with radius 0.25 arcsec)
    Source 0.362 631.02 25.12
    Background 1.793 4,905.10 70.04
        Sky 0.367 639.70 25.29
        Dark Current 1.426 2,483.40 49.83
        Post Flash 1,782.00 42.21
    Read Out 56.64
Total in selected region 2.155 5,536.12 93.51
Brightest Pixel (single exposure) 0.115 111.02
Global Count Rates
    Source only 0.421 733.704
    Background (sky+dark) 372,006.438 648,035,214.87
    Post Flash 369,098,752.00
Background per unit area
    Sky Background (arcsec-2) 1.870 3,257.965
    Dark Current (arcsec-2) 7.197 12,537.999
    Post Flash (arcsec-2) 9,075.65
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: 11 e-


Target: [point source]
Spectrum: Castelli-Kurucz Models B5V 15000 4.0
Extinction E(B-V): None
Normalization: Renormalized to vegamag = 23.32 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