本文選題：高紅移 + 恒星形成�。� 參考：《沈陽師范大學(xué)》2017年碩士論文

【摘要】：高紅移星系的結(jié)構(gòu)是星系形成與演化研究目前最前沿的方向之一,但是由于高紅移星系在靜止坐標(biāo)系輻射波段的紅移和cosmic dimming效應(yīng),很久以來對(duì)高紅移星系結(jié)構(gòu)的研究進(jìn)展緩慢。直到近10年來,借助于哈勃空間望遠(yuǎn)鏡(HST)WFC3/近紅外波段高分辨率圖像數(shù)據(jù),人們才對(duì)高紅移星系的結(jié)構(gòu)性質(zhì)有了比較多的認(rèn)識(shí)。星系的等光強(qiáng)輪廓性質(zhì)與星系的內(nèi)部結(jié)構(gòu)性質(zhì)緊密相關(guān)。通過研究星系的等光強(qiáng)輪廓性質(zhì)及其隨紅移的演化,能為探索星系結(jié)構(gòu)的演化提供線索。目前對(duì)中高紅移星系的等光強(qiáng)輪廓的研究還是空白。在本文中,我們從CANDELS巡天的GOODS-S和UDS兩個(gè)場(chǎng)中,一共選取了約4600個(gè)紅移z=0.5-1.8的恒星形成星系(SFGs),并對(duì)它們的徑向橢率(ε)輪廓和盤狀/盒狀(disky/boxy)參數(shù)輪廓進(jìn)行了正確的測(cè)量�；谶@些數(shù)據(jù),我們首次對(duì)中高紅移的恒星形成星系的橢率ε輪廓和輪廓在恒星質(zhì)量——紅移演化網(wǎng)格上的統(tǒng)計(jì)性質(zhì)進(jìn)行了分析。根據(jù)星系在每個(gè)紅移區(qū)間內(nèi)的相對(duì)大小,我們將樣本星系劃分成兩類:“小”的恒星形成星系(SSFGs)和“大”的恒星形成星系(LSFGs),主要研究結(jié)果如下:(1)在低恒星質(zhì)量(M*10 M⊙)端,側(cè)向(edge-on)和面向(face-on)SSFGs均擁有接近水平的ε和輪廓,并且所有半徑處的中值(median value)近似為0;然而,側(cè)向LSFGs的橢率輪廓其主要特征是隨半徑單調(diào)上升,同時(shí)星系的中部區(qū)域呈現(xiàn)盤狀(disky)特性(A40)。(2)在高恒星質(zhì)量(M*10 M⊙)端,側(cè)向SSFGs和LSFGs的橢率輪廓和A4輪廓均呈現(xiàn)先上升到最大值然后再下降的趨勢(shì)。同時(shí),星系的中部區(qū)域呈現(xiàn)更為顯著的盤狀特性。這些特征在更低紅移(z1.4)或在更高質(zhì)量(M*10.M⊙)端更為明顯。(3)沿著恒星質(zhì)量——紅移網(wǎng)格上的演化路徑,SSFGs和LSFGs的中心區(qū)域(R=1.5 kpc處)的橢率呈下降趨勢(shì)。以上觀測(cè)研究結(jié)果說明:在中高紅移處,低質(zhì)量SSFGs內(nèi)可能還沒有形成恒星盤(或其“恒星盤”與鄰近宇宙中的盤星系具有不同的結(jié)構(gòu)),而低質(zhì)量LSFGs的結(jié)構(gòu)與鄰近盤星系的結(jié)構(gòu)相似。在恒星形成星系朝低紅移和高質(zhì)量的演化過程中,內(nèi)部區(qū)域的核球(大部分為偽核球,pseudo-bulge)和外圍的恒星暈(outer stellar halo)伴隨著其中間區(qū)域的盤的演化一并增長(zhǎng)。
[Abstract]:The structure of Gao Hong shifted galaxies is one of the most advanced directions in the field of galaxy formation and evolution. However, due to the redshift and cosmic dimming effect of the Gao Hong shift galaxies in the stationary coordinate band, the research on the structure of the Gao Hong shifted galaxies has been slow for a long time. Only in the last 10 years, with the help of the Hubble Space Telescope (Hubble Space Telescope) with the help of high resolution image data in the near infrared band, the structure and properties of the Gao Hong shift galaxies have been well understood. The equiintensity profile of galaxies is closely related to the inner structure of galaxies. By studying the properties of isochromatic contours of galaxies and their evolution with redshift, we can provide clues for exploring the evolution of galaxy structure. At present, the study of the isochromatic profile of the Gao Hong shift galaxy is still blank. In this paper, from the GOODS-S and UDS fields of the CANDELS survey, we have selected about 4600 star forming galaxies with redshift zn 0.5-1.8, and measured their radial ellipsometry (蔚) profile and disk / box-shaped disky / boxyy parameter profile correctly. Based on these data, for the first time, we analyze the statistical properties of the ellipticity 蔚 profile and the profile of the star mass red-shift evolution grid of the star formation galaxy with the mid-Gao Hong shift. According to the relative size of galaxies in each redshift region, we divide the sample galaxies into two categories: "small" star forming galaxies (SSFGs) and "large" star forming galaxies (LSFGs1). Both the lateral edge-on) and the face-ona-facing SSFGs have nearly horizontal 蔚 and profile, and the median value at all radii is approximately zero. However, the ellipticity profile of the lateral LSFGs increases monotonously with the radius. At the same time, the central region of the galaxy presents a disk-like diskyproperty (A40). (2) at the end of 10 M) of high mass star, the ellipticity profile and A4 profile of lateral SSFGs and LSFGs increase to the maximum first and then decrease. At the same time, the central region of the galaxy presents a more significant disc-like feature. The ellipticity of these characteristics is more obvious at the lower redshift z1.4) or in the higher mass (10.M) end), along the evolution path of the star mass-red-shift grid and at the central region of LSFGs (R1. 5 kpc). The results of the above observations show that: at the middle Gao Hong shift, There may not be a stellar disk in low-mass SSFGs (or its "stellar disk" has different structures from disk galaxies in the adjacent universe, while the structure of low-mass LSFGs is similar to that of neighbouring disk galaxies. During the evolution of star forming galaxies towards low redness and high mass, the nuclear sphere in the inner region (mostly pseudo-bulge) and the outer star halo outer stellar are accompanied by the evolution of the disk in the middle region.
【學(xué)位授予單位】：沈陽師范大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：P152

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本文編號(hào)：1988972