Surface photometry of emission-line galaxies in low density regions
Surface photometry of emission-line galaxies in low density regions
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低密度区域发射线星系的表面光度测量
DOI：
10.1051/aas:2000160
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
C. Popescu
中科院分区：
文献类型：
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作者：
J. Vennik;U. Hopp;C. Popescu
对139个暗发射线星系和2个非发射线星系进行了详细的B和R面测光。它们是Popescu等人选择的ELG样本的子样本。(1996 1998年），四个相邻的空洞。我们推导出等照度线和积分光度参数和径向表面亮度（SB）的配置文件。我们的样本主要由低光度（= 0）、小线性尺寸（= 6.0kpc）（H 0 = 75 kms-1 Mpc-1）和蓝色（= 0.93）星系组成。大约83%的ELG属于蓝色紧凑星系（BCGs），其他的是发光的星暴核星系（SBNs）和一些相互作用的对。72%的ELG具有一个单一的优势HII区，而其余的28%显示多节。此外，71%的ELG显示规则的外部等照度线，其余29%的显示干扰外部形态。
我们通过解开恒星盘和指数盘上方的多余光来进行SB剖面分解。我们将配置文件分为5种类型：纯磁盘配置文件（研究139 ELG的21%）;显示磁盘和凸起/核/HII结组件的配置文件（37%）;具有中心光抑制的配置文件（13%）;非盘状（凹）配置文件（7%）;几乎未解析（准恒星）图像和恒星SB配置文件（22%）。
Popescu等人（（1997）发现大多数被研究的ELG遵循CfA红移巡天中“正常”星系的空间分布。15个ELG和1个非ELG被归类为隔离良好，分布在附近（0.033）空隙内。我们发现这些孤立的ELG几乎都是矮星系，它们的光度和颜色与附近的非孤立ELG相似。对于15个孤立的ELG中的8个，已检测到潜在的LSBG。孤立的ELG的底层磁盘往往是更大和更低的SB，比非孤立的ELG的磁盘（相同的总蓝色通量）。
Detailed B and R surface photometry is performed for 139 faint emission-line galaxies (ELGs) and for 2 non-ELGs. They are a subsample of the ELG sample selected by Popescu et al. (1996, 1998) towards four nearby voids. We derived the isophotal and integral photometric parameters and radial surface brightness (SB) profiles. Our sample consists mostly of low luminosity (), small linear size ( = 6.0 kpc) ( H 0 = 75 km s -1 Mpc -1 ) and blue ( = 0.93) galaxies. About 83% of the studied ELGs belong to the class of Blue Compact Galaxies (BCGs); others are luminous Starburst Nucleus Galaxies (SBNs) and a few interacting pairs. 72% of the ELGs possess a single dominant HII region, while the remaining 28% show multiple knots. Furthermore 71% of the ELGs show regular outer isophotes, and the remaining 29% reveal disturbed outer morphologies.
We performed the SB profile decomposition by means of disentangling the underlying stellar disk and the excess light above the exponential disk. We classified the profiles into 5 types: pure disk profiles (21% of studied 139 ELGs); profiles that show both disk and bulge/nucleus/HII knot components (37%); profiles that have central light depression (13%); non-disky (concave) profiles (7%); and almost unresolved (quasi-stellar) images and stellar SB profiles (22%).
Popescu et al. ((1997) found that most of the studied ELGs follow the spatial distribution of “normal” galaxies from the CfA Redshift Survey. 15 ELGs and 1 non-ELG were classified as being well isolated and are distributed within nearby ( 0.033) voids. We found that these isolated ELGs are almost all dwarf galaxies with , they show similar luminosities and colours as the nearby non-isolated ELGs. For 8 of 15 isolated ELGs an underlying LSBG has been detected. The underlying disks of isolated ELGs tend to be larger and of lower SB, than the disks of non-isolated ELGs (of the same total blue flux).