此論文的研究主題為找尋GW Vir 類型白矮星─ HIP 3678A 的p-模式震盪。使
用架設在西班牙Calar Alto 天文台的1.23米和2.2米的高速測光系統MIOSOTYS ，
在2014和2015年以20赫茲的頻率觀測HIP 3678 各三個晚上。觀測數據經處理和分
析後，未偵測到白矮星HIP 3678A 的p-模式震盪。在三個標準差的信心水準下，
估計在頻率2到10赫茲間， HIP 3678A 的p-模式震盪相對震幅上限為1.7x10^-4。

In order to search for p-mode oscillations in HIP 3678 A(a GW Vir star, alias
WD 0044-121), the central star of planetary nebula NGC246, we use MIOSOTYS,
a multi-fiber photometer mounted on the 1.23-m and 2.2-m telescopes at Calar Alto
Observatory to observe HIP 3678 with a 20-Hz cadence for 3 nights in both 2014
and 2015. As a result, p-mode oscillations have not been detected in HIP 3678 A. We
estimate the upper limit to the relative amplitude of p-mode oscillations at 1.7x10^-4, in the frequency range from 2 to 10 Hz.

致謝i
Acknowledgments ii
摘要iii
Abstract iv
Contents v
List of Figures vi
List of Tables vii
1 Introduction 1
1.1 Pulsating White Dwarfs . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2 Observations and Data reduction 9
2.1 Observations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.2 Data reduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3 Timing Analysis 17
3.1 Fourier power and relative amplitude . . . . . . . . . . . . . . . . . . . 17
3.2 Probability Distribution . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4 Results and Discussions 19
4.1 Periodicity search . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.2 Summary and discussion . . . . . . . . . . . . . . . . . . . . . . . . . . 29
A Appendix: Examination of the timing analysis 32
References 34

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