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    Please use this identifier to cite or link to this item: http://ir.lib.ncu.edu.tw/handle/987654321/6130

    Title: 鹿林一米望遠鏡對彗星17P/Holmes 2007爆發的觀測與分析;Lulin Observations and Study of the 2007 Outburst of 17P/Holmes
    Authors: 林建賢;Chien-Hsien Lin
    Contributors: 天文研究所
    Keywords: 彗星;彗髮;爆發;comet;coma;outburst
    Date: 2009-01-12
    Issue Date: 2009-09-22 10:13:41 (UTC+8)
    Publisher: 國立中央大學圖書館
    Abstract: 主旨:有關彗星17P/Holmes在2007年的大爆發之可見光波段的觀測與研究。此次大爆發推算發生起始時間為2007年十月23.7±0.2 UT (Sekanina, 2007)。 目標:研究17P彗星爆發後內部灰塵彗髮的型態演化和其細節結構,以及估算彗髮裡灰塵粒子的運動速度與噴發出來的質量。 方法:自2007年十月24號第一天得到17P彗星爆發的報告後,我們便使用鹿林天文台的一米望遠鏡(LOT)對此顆彗星做密集的觀測,持續到大約十一月中,並且使用了Bessel寬波段以及Rosetta窄波段兩種濾鏡去觀測彗星。我們從所有資料中選取了每一天的一張R波段影像出來,用來代表彗星的灰塵彗髮,並且使用了不同的影像處理與分析方法,讓彗髮中的細微變化顯現出來,與推算所需數值。 結果:在爆發之後的42小時之內,17P的總亮度從原本的17等迅速的升到2.7等。陳列每一天的影像則顯示出了其彗髮型態上的變化,其中影像中的兩個亮度中心分別代表了其彗核以及彗髮雲凝結中心的位置。在17P爆發後早期的演化中,其彗髮雲中心是由固定速度從彗核分離出來,速度約為0.132± 0.004 km/s。其球狀彗髮的半徑也在固定地增加,擴張的速度約為0.554 ± 0.005 km/s。我們也在爆發後三天的十月27號,在彗核表面附近發現了另一個小噴流。而彗星中主要噴流對平均彗髮的質量比約為6%。我們也大略地推算出爆發殼層的總質量約2.2 x 1010 kg,為彗核總質量的0.25%。 Context: The optical band study of the 2007 outburst of comet 17P/Holmes, which was estimated to begin on Oct. 23.7±0.2 UT (Sekanina, 2007). Aims: The morphological evolution of 17P’s inner dust coma in detail and the estimation of dynamical motion and total mass of ejected dust grains. Methods: Following the first report of this extraordinary cometary outburst, comprehensive observations were performed with Lulin One-meter Telescope (LOT) until mid November using Bessel wide-band and Rosetta narrow-band cometary filters. We extracted one R-band image from each day’s data representing for the dust coma and applied different processions to the images for revealing the detailed variation of the inner coma and estimating the required values. Results: The total brightness of 17P steeply increased from 17 to 2.7 of magnitude within 42 hours after the massive outburst. The diagrams day by day reveal the morphological evolution containing two peaks of nucleus and coma blob. In the early evolution the separation velocity between the nucleus and the coma blob was estimated approximately to be a constant value of 0.132± 0.004 km/s, and the expansion speed of the spherical coma was also a constant rate of about 0.554 ± 0.005 km/s. We found a minor eruption on the nuclear surface since Oct. 27, three days after the discovery of the outburst. The mass ratio of the main jets to the mean spherical coma is 6%. The ejected mass within the outburst shell has been estimated to be 2.2 x 1010 kg, about 0.25% of the total nuclear mass.
    Appears in Collections:[天文研究所] 博碩士論文

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