Conditions for detecting lensed Population III galaxies in blind surveys with the James Webb Space Telescope , the Roman Space Telescope , and Euclid
Conditions for detecting lensed Population III galaxies in blind surveys with the James Webb Space Telescope , the Roman Space Telescope , and Euclid
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用詹姆斯·韦伯太空望远镜、罗马太空望远镜和欧几里得进行盲探探测第三族透镜星系的条件
DOI：
10.1093/mnras/stac488
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发表时间：
2022
影响因子：
4.8
通讯作者：
Sahlén, Martin
中科院分区：
文献类型：
--
作者：
Vikaeus, Anton;Zackrisson, Erik;Schaerer, Daniel;Visbal, Eli;Fransson, Emma;Malhotra, Sangeeta;Rhoads, James;Sahlén, Martin
暗物质晕，达到高冷却质量没有事先星星形成或外部金属污染的潜在网站，为形成小-非常微弱-人口III星系在高红移。引力透镜效应在极少数情况下可能会将它们的通量提高到可检测的水平，但要在天空中随机选择的区域中发现即使是少量的此类物体，也需要对非常大的区域进行调查。正因为如此，一个小的、宽视场的望远镜原则上可以比一个视场较小的大望远镜提供更好的探测前景。在这里，我们推导出最小的共动数密度，使引力透镜能够将这些物体的红移= 5−16，超过詹姆斯·韦伯太空望远镜（JWST）、罗马太空望远镜（JWST）和欧几里德天文台进行的盲测的探测阈值。我们发现Pop III星系的光度探测前景是很有希望的，并且RST比JWST和Euclid更好。然而，流行III星系目前的模拟青睐的数量密度太低，以允许光谱检测的基础上的Heii 1640发射线的强度在任何考虑的调查，除非非常高的星星形成效率（彗星0.1）诱发。我们认为，针对个别集群透镜，而不是在本文中考虑的宽视场调查结果在更好的光谱检测前景，而光度检测，宽视场调查表现得更好。
Dark matter haloes that reach the Hi-cooling mass without prior star formation or external metal pollution represent potential sites for the formation of small – extremely faint – Population III galaxies at high redshifts. Gravitational lensing may in rare cases boost their fluxes to detectable levels, but to find even a small number of such objects in randomly selected regions of the sky requires very large areas to be surveyed. Because of this, a small, wide-field telescope can in principle offer better detection prospects than a large telescope with a smaller field of view. Here, we derive the minimum comoving number density required to allow gravitational lensing to lift such objects at redshiftz= 5−16 above the detection thresholds of blind surveys carried out with theJames Webb space telescope(JWST), theRoman space telescope(RST) andEuclid. We find that the prospects for photometric detections of Pop III galaxies are promising, and that they are better forRSTthan forJWSTandEuclid. However, the Pop III galaxies favoured by current simulations have number densities too low to allow spectroscopic detections based on the strength of the Heii1640 emission line in any of the considered surveys unless very high star formation efficiencies (ϵ ≳ 0.1) are evoked. We argue that targeting individual cluster lenses instead of the wide-field surveys considered in this paper results in better spectroscopic detection prospects, while for photometric detection, the wide-field surveys perform considerably better.