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LONG-TERM VARIATION OF THE SHUTTER DELAY TIME OF Y4KCAM OF THE CTIO 1.0 M TELESCOPE

  • Lee, Jae-Woo (Department of Physics and Astronomy, Sejong University) ;
  • Pogge, Richard (Department of Astronomy, Ohio State University)
  • 투고 : 2016.11.02
  • 심사 : 2016.12.09
  • 발행 : 2016.12.31

초록

We investigate the long-term spatial drift of the center and the temporal variation of the shutter delay time map of Y4KCam mounted on the CTIO 1.0 m telescope. We have collected shutter delay time maps over eight years as a part of our long-term survey program. We find that the center of the shutter delay time map can drift up to $450{\mu}m$, equivalent to ${\approx}30pixels$, on the CCD. This effect can result in a small amount of error in integration time without the proper shutter delay time correction, but it does not appear to cause any significant problems in photometric measurements. We obtain a mean shutter delay time of $69.1{\pm}0.8$ ms and find no temporal variation of the shutter delay time of Y4KCam over eight years, indicative of the mechanical stability of the shutter. We suggest that using a master shutter delay time correction frame would be sufficient to achieve high precision photometry, which does not exceed photometric errors ${\approx}1.7mmag$ across the CCD frame for exposure times longer than 1 s.

키워드

참고문헌

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피인용 문헌

  1. Multiple Stellar Populations of Globular Clusters from Homogeneous Ca-CN Photometry. II. M5 (NGC 5904) and a New Filter System vol.844, pp.1, 2017, https://doi.org/10.3847/1538-4357/aa7b8c
  2. Multiple Stellar Populations of Globular Clusters from Homogeneous Ca–CN Photometry. III. NGC 6752 vol.238, pp.2, 2018, https://doi.org/10.3847/1538-4365/aadcad