Application of fast CCD drift scanning to speckle imaging of Binary stars

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Application of fast CCD drift scanning to speckle
imaging of Binary stars
A A Preprint Astro-ph/0403107 4 Mar 2004
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• Drift scanning --- taking the image by scanning
  over the target
• e.g., turning off the RA tracking
• e.g., stellar image remains fixed but read out
  the CCD photoelectrons in a controlled way

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Application 1 Lunar occultation
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Instruments C14 with an ST-8 (TC211 chip,
192x164 pixels ? T lt 4 mas with R filter bandwidth
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Application 2 speckle imaging

• Speckle imaging --- fast imaging to freeze the
  atmospheric turbulence tens cycles per second
  (a poor mans space telescope)

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Instruments 1.5 m at Calar Alto (Spain) with the
same LO SBIG ST-8 camera with a TI TC-211 chip,
readout through a parallel port, f12280 mm R
filter (?641 /- 100 nm) ? diffr. spot 108
mas Four binary systems observed in
2001 Seeing1.3 ? atm. Coherence time 4 ms
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• Fourier analysis and self-calibration
• subtracting bias, streaks - autocorrelation
  low-order bispectral subplanes- FT ? phase map
  modulus ? FT-1

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(No Transcript)
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Effects of calibration by different point sources
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Results of double star speckle imaging
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Comparing/combining with other results
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Further CCD improvements

• Readout noise
• multiple outputs
• new data transfer interfaces

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Something relevant, aka. why would I care to
read/report this paper anyway?
TAOS observations of a stellar occultation by an
asteroid
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http//www.astro.ncu.edu.tw/contents/faculty/wp_ch
en/wp_chen/nemausa20040221.pdf
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LOT results, observed by A. Chen, processed by C.
W. Chen