train:lectures:telescopeoptics

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train:lectures:telescopeoptics [2024/03/24 12:48] – Roy Proutytrain:lectures:telescopeoptics [2024/03/24 12:54] (current) – Roy Prouty
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 [{{:train:lectures:20240321_airyseeing.png?800|Single Airy Profile with fit. Sum of many Airy Profiles with fit.}}] [{{:train:lectures:20240321_airyseeing.png?800|Single Airy Profile with fit. Sum of many Airy Profiles with fit.}}]
 +Consider a telescope unencumbered by pesky atmosphere and is therefore observing an Airy Disk when observing a point source. Take the $x$ axis to be the number of pixels relative to the center of the profile and estimate the Angular Resolution.
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 +====Seeing Limited====
  
  
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 [{{https://www.astronomynotes.com/telescop/twinkle.gif|Poor Seeing Geometry}}]\\ [{{https://www.astronomynotes.com/telescop/twinkle.gif|Poor Seeing Geometry}}]\\
-Consider a telescope unencumbered by pesky atmosphere and is therefore observing an Airy Disk when observing a point source. Take the $x$ axis to be the number of pixels relative to the center of the profile and estimate the Angular Resolution. 
  
-====Seeing Limited==== 
 Due to the turbulent and inhomogeneous atmosphere, rays of light have many opportunities to refract upon impinging a volume of atmosphere with differing optical properties (think: index of refraction from Snell's Law). These refraction events have the effect of displacing the center of the Airy Profile. By the Central Limit Theorem, the sum$^1$ of many displaced Airy Profiles approaches a Gaussian Profile. This gives us confidence in our choice of a Gaussian PSF (though there are better-matching PSF models; e.g., Moffat Profile). Due to the turbulent and inhomogeneous atmosphere, rays of light have many opportunities to refract upon impinging a volume of atmosphere with differing optical properties (think: index of refraction from Snell's Law). These refraction events have the effect of displacing the center of the Airy Profile. By the Central Limit Theorem, the sum$^1$ of many displaced Airy Profiles approaches a Gaussian Profile. This gives us confidence in our choice of a Gaussian PSF (though there are better-matching PSF models; e.g., Moffat Profile).
  
-Determine the effective angular resolution of the "Sum of 3000 Disp. Airys" profile shown below. Assume the ASI 432 is placed on the main scope.+Determine the effective angular resolution of the "Sum of 3000 Disp. Airys" profile shown above. Assume the ASI 432 is placed on the main scope.
  
 An optical system whose angular resolution is limited by these repeated refraction events is said to be **Seeing Limited**. An optical system whose angular resolution is limited by these repeated refraction events is said to be **Seeing Limited**.
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 ====CODE==== ====CODE====
-[[https://colab.research.google.com/drive/1SocmlQtnegS2GoyTZN7gaM840_eHzxcI?usp=sharing|Google Colab for Detector Basics I]]+[[https://colab.research.google.com/drive/1SocmlQtnegS2GoyTZN7gaM840_eHzxcI?usp=sharing|Google Colab for Telescope Optics II]]
  
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