arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1104.0931astro-ph.CO
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E-CDFS中的引力透镜候选物

Gravitational lens candidates in the E-CDFS

A. More, K. Jahnke, S. More, A. Gallazzi, E. F. Bell, M. Barden, B. Haeussler

摘要:

我们在GEMS调查的E-CDFS中报告了10个镜头候选者。其中九个系统是新的检测,只有一个候选系统是已知的透镜系统。对于最有前途的五个系统,包括已知的镜头系统,我们提出了初步的镜头质量建模,测试的结果,如果候选人是合理的镜头系统。利用COMBO-17星系表计算了候选透镜星系的测光红移。利用$z$波段光度和基于$V-z$颜色的恒星质光比计算了候选透镜星系在爱因斯坦半径范围内的恒星质量。正如预期的那样,透镜质量被发现大于候选透镜星系的恒星质量。与SLACS和COSMOS中的透镜相比,这些候选者具有相似的暗物质分数。它们也大致遵循晕下丰度匹配技术预测的晕质量-恒星质量关系。其中一个候选透镜星系有资格成为LIRG,但可能不是真正的透镜,因为系统中的弧形特征可能是候选透镜星系中恒星形成的活跃区域。在五个最佳候选者中,一个是确认的透镜系统,一个是可能的透镜系统,两个是不太可能的透镜,并且候选者之一的状态是模糊的。仍然需要对这些系统进行光谱跟踪,以确认透镜效应和/或更准确地确定透镜质量和质量密度分布。

英文摘要:

We report ten lens candidates in the E-CDFS from the GEMS survey. Nine of the systems are new detections and only one of the candidates is a known lens system. For the most promising five systems including the known lens system, we present results from preliminary lens mass modelling, which tests if the candidates are plausible lens systems. Photometric redshifts of the candidate lens galaxies are obtained from the COMBO-17 galaxy catalog. Stellar masses of the candidate lens galaxies within the Einstein radius are obtained by using the $z$-band luminosity and the $V-z$ color-based stellar mass-to-light ratios. As expected, the lensing masses are found to be larger than the stellar masses of the candidate lens galaxies. These candidates have similar dark matter fractions as compared to lenses in SLACS and COSMOS. They also roughly follow the halo mass-stellar mass relation predicted by the subhalo abundance matching technique. One of the candidate lens galaxies qualifies as a LIRG and may not be a true lens because the arc-like feature in the system is likely to be an active region of star formation in the candidate lens galaxy. Amongst the five best candidates, one is a confirmed lens system, one is a likely lens system, two are less likely to be lenses and the status of one of the candidates is ambiguous. Spectroscopic follow-up of these systems is still required to confirm lensing and/or for more accurate determination of the lens masses and mass density profiles.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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