Surface Photometry of Galaxies (Effect of seeing)

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Surface Photometry of Galaxies(Effect of seeing)

• Jae Gyu, Byeon

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? Surface Photometry of Galaxy

• ? An essential step towards putting the
  morphology of galaxies is the measurement of
  galaxies surface-brightness distributions.
• ? This if a difficult undertaking for two
  reasons.
• ? First, the sky is never completely dark.
• ? Second, the atmosphere is not completely
  transparent.
• ? seeing
• ? The blurring of images by the atmosphere
• ? The seeing is characterized by the
  point-spread functing(PSF)

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? Effect of seeing

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• ? The measured brightness at location R
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• ? The simplest case of a circularly-symmetric
  surface-brightness
• distribution and a Gaussian PSF

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? Effect of seeing

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? Effect of seeing

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? Effect of seeing

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? Effect of seeing

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? Effect of seeing

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