EAPSI: Studying the first light in the early universe

当宇宙历史上的第一批恒星形成时，它们开始发出光，也就是众所周知的光子。人们相信，这种光可以被观察到是一种微弱的光芒，使用红外望远镜可以在天空的各个方向看到它。测量这种微弱的辉光，被称为宇宙近红外背景(Nirb)，可以被认为是间接地观察第一批光源。韩国光州朝鲜大学的安京镇教授最近进行了一个高分辨率的宇宙学模拟，捕捉到了第一批光源的形成过程。利用这些模拟，将建立第一源及其周围环境的性质与观测到的Nirb之间的联系。这项研究将研究第一光源和Nirb之间的相关性。通过研究这种相关性，可以更好地了解宇宙的历史。研究宇宙将为无法通过地球实验研究的物理学提供测试，从而导致人类知识和技术发展的进一步进步。有了这个数据集，将计算得到的光谱，然后可以与实际观测进行比较。此外，由于某些因素，如恒星形成率、产生的光子数和初始质量函数，事先是已知的，因此可以准确地理解这些参数是如何在Nirb中表现出来的。对这些参数施加更严格的限制，也将有助于更好地理解一种不同的天体物理事件--宇宙再电离，当时宇宙从充满中性氢的状态转变为电离等离子体的海洋。该NSF EAPSI奖是与韩国国家研究基金会合作资助的。

When the first stars in the history of the universe were formed, they began to emit light, known as photons. It is believed that this light can be observed as a faint glow that is seen in every direction in the sky using infrared telescopes. Measuring this faint glow, referred to as the Cosmic Near-Infrared Background (NIRB), can be thought of as indirectly looking at the first sources of light. Professor Kyung-jin Ahn at Chosun University in Gwangju, South Korea, has recently run a high-resolution cosmological simulation that captures the formation of the first sources of light. Using these simulations, the connections between the properties of the first sources and their surroundings and the observed NIRB will be made. This research will study the correlation between the first sources of light and the NIRB. In studying this correlation, a better understanding about the history of the universe can be gained. Studying the universe will provide tests for physics that cannot be studied through experimentation on Earth, thereby leading to further advancements in human knowledge and technological developments.With this dataset, the resulting spectrum will be calculated, which can then be compared with the actual observations. Furthermore, because certain factors, such as star formation rates, the number of photons produced, and the initial mass function, are known in advance, precisely how these parameters manifest themselves in the NIRB can be understood. Putting a tighter limit on these parameters will also lead to a better understanding of a different astrophysical event, Cosmic Reionization, when the universe transformed from being filled with neutral hydrogen to a sea of ionized plasma. This NSF EAPSI award is funded in collaboration with the National Research Foundation of Korea.