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

范祖佾(Tsu-I Fan)

指導教授 ： 張祥光

國立清華大學/理學院/天文研究所/碩士(2012年)

https://doi.org/10.6843/NTHU.2012.00256

摘要

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。

關鍵字

白矮星 ； 星震 ； 緻密星體

並列摘要

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.

並列關鍵字

white dwarfs ； asteroseismology ； compact objects

參考文獻

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