| DC 欄位 |
值 |
語言 |
| DC.contributor | 天文研究所 | zh_TW |
| DC.creator | 陸勇志 | zh_TW |
| DC.creator | Loke, Young Tzee | en_US |
| dc.date.accessioned | 2019-8-19T07:39:07Z | |
| dc.date.available | 2019-8-19T07:39:07Z | |
| dc.date.issued | 2019 | |
| dc.identifier.uri | http://ir.lib.ncu.edu.tw:88/thesis/view_etd.asp?URN=104229004 | |
| dc.contributor.department | 天文研究所 | zh_TW |
| DC.description | 國立中央大學 | zh_TW |
| DC.description | National Central University | en_US |
| dc.description.abstract | 我們研究了類星體的顏色變化的特性。我們交叉比對史隆數位化巡 (SDSS) 所釋出的第七版資料 (DR 7) 和第十二版資料 (DR 12) 的類星體目錄，選出 608 個在兩個版本都有觀測資料且紅移在 0.3 到 1.2 之間的類星體。我們選用在靜止坐標系下 3000 埃與 4000 埃的光通量密度比值來定義顏色值。我們透過比較兩個版本類星體的顏色值來定義顏色變化。我們發現在靜止坐標系下，類星體的顏色變化分佈類似常態分佈，但部分類星體在數年的時間尺度下有著明顯的顏色變化。另外，我們還發現了八個類星體的光譜變化可以被塵埃紅化現象來解釋。我們的結果也顯示了類星體的顏色變化可能存在多個物理機制。 | zh_TW |
| dc.description.abstract | We investigate the color variabilities of QSOs at z = 0.3 – 1.2. We selected the sample of 608 QSOs, which have multi-epoch spectra in both the Sloan Digital Sky Survey (SDSS) Data Released 7 (DR7) and Data Released 12 (DR12). We defined the spectral color ofthe QSOs by the ratio of flux densities of 3000 Å to 4000 Å in the rest frame. In each sample, the color variability is defined by the differences of color in DR7 and DR12.We find that the color variabilities show a Gaussian distribution with some QSOs displaying significant color changes within the timescale of a few years. We find that the spectral variabilities of eight color-change QSOs could be explained by dust reddening. Our results also show that the color variabilities of QSOs might originate from more than one physics mechanisms. | en_US |
| DC.subject | 類星體 | zh_TW |
| DC.subject | 活躍星系核 | zh_TW |
| DC.subject | 星系 | zh_TW |
| DC.subject | QSO | en_US |
| DC.subject | AGN | en_US |
| DC.subject | Galaxy | en_US |
| DC.title | Color Variabilities of QSOs at z = 0.3 - 1.2 | en_US |
| dc.language.iso | en_US | en_US |
| DC.type | 博碩士論文 | zh_TW |
| DC.type | thesis | en_US |
| DC.publisher | National Central University | en_US |