研究目的
To assess the quality of Dome C in Antarctica for photometric observations in the visible, detect and characterize variable objects, and evaluate the site's potential for time series astronomy.
研究成果
The study demonstrates that Dome C offers high-quality conditions for photometric observations, with a photometric weather fraction of 67.1% and the ability to achieve nearly continuous coverage during Antarctic winters. The data enabled the detection of new variable stars and eclipsing binaries, highlighting the site's potential for time series astronomy. Improvements in instrument stability and data reduction methods over the years enhanced the quality of observations, supporting the feasibility of long-term astronomical projects at Dome C.
研究不足
The instrument suffered from shutter malfunctions after two winters, requiring temperature adjustments and specific calibration methods. Thermal instability, especially in 2009, led to PSF variations and poor data quality. The fixed pointing and elongated PSFs introduced challenges in photometric reduction. Data transfer was limited by internet bandwidth at Concordia, necessitating physical shipment of hard drives. The study focused on a specific bandpass (579-642 nm) and may not generalize to other wavelengths.
1：Experimental Design and Method Selection:
The study used ASTEP South, a fixed 10 cm refractor telescope pointing continuously at the celestial south pole to minimize jitter and airmass variations. Data were collected over four Antarctic winters (2008-2011). Specific data reduction methods were developed to handle elongated PSFs due to star rotation on the CCD.
2：1). Specific data reduction methods were developed to handle elongated PSFs due to star rotation on the CCD.
Sample Selection and Data Sources:
2. Sample Selection and Data Sources: Observations focused on stars near the celestial south pole, with a catalog of 5954 target stars compiled from UCAC3, UCAC2, Tycho-2, and APASS catalogs. Data included science images, bias frames, darks, and flats.
3：List of Experimental Equipment and Materials:
ASTEP South instrument (10 cm refractor, CCD camera, thermalized enclosure), computers for data control and storage, external hard drives for data transfer, software for image calibration and photometric analysis (e.g., IDL, Period04).
4：4).
Experimental Procedures and Operational Workflow:
4. Experimental Procedures and Operational Workflow: The instrument operated automatically, taking exposures of 29 s with 10 s overheads. Calibration images (bias, darks, flats) were acquired regularly. Data were reduced using custom algorithms for field matching, photometry with optimized apertures, and correction of systematic effects like one-sidereal day patterns.
5：Data Analysis Methods:
Lightcurves were built and analyzed for variability using the box least square (BLS) algorithm. Fourier analysis was performed with Period04 software. Weather quality was inferred from lightcurve dispersions, and statistical methods were applied to classify photometric conditions.
独家科研数据包，助您复现前沿成果，加速创新突破
获取完整内容
