研究生: |
范祖佾 Fan, Tsu-I |
---|---|
論文名稱: |
白矮星RX J2117.1+3412的p模式震盪之搜尋 Search for p-mode oscillations in white dwarf RX J2117.1+3412 |
指導教授: |
張祥光
Chang, Hsiang-Kuang |
口試委員: |
張祥光
Chang, Hsiang-Kuang 陳惠茹 Chen, Huei-Ru 周翊 Chou, Yi |
學位類別: |
碩士 Master |
系所名稱: |
理學院 - 天文研究所 Institute of Astronomy |
論文出版年: | 2012 |
畢業學年度: | 100 |
語文別: | 英文 |
論文頁數: | 47 |
中文關鍵詞: | 白矮星 、星震 、緻密星體 |
外文關鍵詞: | white dwarfs, asteroseismology, compact objects |
相關次數: | 點閱:3 下載:0 |
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此篇論文的目的為搜尋GW Vir白矮星RX J2117.1+3414的p模式震盪。2010年時,我們使用架設在1.93米望遠鏡上的高速測光系統MIOSOTYS在50毫秒的時間解析度下對此目標進行了四個晚上的觀測。由於p模式震盪的時間為秒或更短的時間尺度,因此必須採用高速測光系統。我們使用FFT(快速傅立葉變換)以及Lomb-Scargle Periodogram進行數據分析,我們並未在此數據中偵測到p模式震盪。為了估計p模式震盪震幅的上限,我們亦進行了一系列的數據模擬。我們的結論為:在3個標準差的信心水準下,頻率範圍1赫茲至10赫茲之間相對震幅的上限為2.5×10^-3。
The purpose of this thesis is to search for p-mode oscillations in the GW Vir white dwarf RX J2117.1+3412. This target was observed at time resolution 50 ms using a high-speed photometry system MIOSOTYS at a 1.93 m telescope for four nights in 2010. A high-speed photometry system is required since the p-mode oscillations in white dwarfs are at the time scale of seconds or less. We analysed the photometric data by Fast Fourier Transform and the Lomb-Scargle Periodogram. P-mode oscillations were not detected in our analysis. We have also conducted a series of simulations to estimate the upper limits to the p-modes amplitude. We conclude that an upper limit to the relative amplitude can be set at 2.5×10^-3 in the frequency range 1 to 10 Hz with 3σ confidence level.
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