搜尋白矮星 G226-29 的 p 震盪模式

• Main Author: 吳宜珊
• Other Authors: 張祥光
• Format: Thesis
• Language: English
• Published: 2014
• Subjects: 白矮星;p震盪; p-mode oscillation;white dwarf;DAV;G226-29; Orca
• Online Access: http://nthur.lib.nthu.edu.tw/dspace/handle/987654321/85737; http://nthur.lib.nthu.edu.tw/dspace/bitstream/987654321/85737/1/GH02101025505.pdf

GH02101025505 碩士 天文研究所 此篇論文使用高速測光系統MIOSOTYS 和CMOS (互補式金屬氧化物半導體) ORCA-Flash4.0 V2 觀測 (每秒拍攝20張影像)白矮星G226-29來搜尋此白矮星的p震盪模式。在 2013年五月及六月，MIOSOTYS 架設在西班牙1.23 m 望遠鏡觀測白矮星G226-29五個晚上。在2014年二月及五月，ORCA-Flash4.0 V2 架設在鹿林1 m 望遠鏡觀測G226-29 兩個晚上。由傅立葉轉換(DFT)的結果，頻率1-10 赫茲的範圍內，3個標準差的信心水準下，我們並未在觀測中偵測到G226-29 p震盪模式。 在3個標準差的信心水準下，我們給出白矮星G226-29 p震盪模式的相對振幅上限。在MIOSOTYS在西班牙的5個晚上觀測中，相對振幅上限分別是 6.5, 7.1, 7.2, 6.3, 7.0x10-4。 在ORCA-Flash4.0 V2在鹿林2個晚上觀測中，相對振幅上限分別是15.0, 7.0 x10-4。 為了將MIOSOTYS在西班牙的觀測與ORCA-Flash4.0 V2在鹿林的觀測做比較，我們將鹿林五月的數據擷取出與西班牙相同長度的數據來做傅立葉轉換，並得到相對振幅上限7.75 x10-4。 G226-29 有一g模式震盪週期約109秒。在MIOSOTYS觀測中有偵測到此週期，估計偵測到的相對振幅為1.2-7.5x10-3。從ORCA-Flash4.0 V2 觀測結果，109週期並沒有被偵測到，但依據大氣擾動情況差異，評估得出此109秒週期在鹿林可能發生的相對振幅值是落在MIOSOTYS 偵測到的數據範圍內。 We used multi-fiber photometer MIOSOTYS and high-speed photometer CMOS camera ORCA-Flash4.0 V2 to search for p-mode oscillations in DAV white dwarf G226-29. G226-29 was observed on 2013 May 29, June 22-24, and June 27 by MIOSOTYS mounted on the 1.23m telescope at Calar Alto Observatory, Spain and on 2014 Feb 16, May 29 by ORCA-Flash4.0 V2 conducted on the 1m telescope at Lulin Observatory, Taiwan. From the results of Discrete Fourier transform, there is no feature detected above 3σ confidence level in 1-10 Hz. Here we give the 3σ confidence level upper limit of relative amplitude of the p-mode oscillations in our observations. For five night observations by MIOSOTYS at Calar Alto, the upper limits are 6.5, 7.1, 7.2, 6.3, 7.0x10-4, respectively. For two night observations by CMOS camera ORCA-Flash4.0 V2, the upper limits are 15.0, 7.0 x10-4. We also employed same data length as MIOSOTYS data on Lulin 2014 May 29 data, which has upper limit 7.75 x10-4. G226-29 has a g-mode period near 109s. There are detections of G226-29’s 109s period from MIOSOTYS data and the estimated relative amplitudes are 1.2-7.5x10-3. Although the ORCA-Flash4.0 V2 results have no detections, the 109s period still have possibility of detections which are most likely affected by the predominant atmospheric variations.