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来自中国的最新突发新闻。

太空望远镜网络搜索原始黑洞

詹姆斯韦伯太空望远镜的艺术家渲染图。 图片来源:NASA GSFC/CIL/Adriana Manrique Gutierrez

韦伯太空望远镜团队 继续工作 包在我身上 调试 这是夏季科学作业开始前的最后一步。 我们最近看到了令人惊叹的照片 我们银河系中心的一个黑洞,银河系事件视界望远镜. 现代天文学的谜团之一是每个人有多大 星系 他来有一个巨大的中央 黑洞以及即使在宇宙的早期,这些黑洞中的一些是如何大得惊人的。 我们请 Webb 的 NIRSpec 团队成员 Roberto Maiolino 告诉我们 Webb 将如何帮助回答其中一些问题。

“韦伯即将揭开的最激动人心的发现领域之一是在早期宇宙中寻找原始黑洞。这些是天文学家在银河系核心中发现的最大质量黑洞的种子。大多数(也许是全部)星系的中心有黑洞,它们的质量范围从我们太阳质量的数百万到数十亿倍不等,这些超大质量黑洞通过吞噬周围的物质以及合并较小的黑洞而变得非常大。

“最新的有趣发现是发现了超大质量黑洞,其质量为数十亿太阳质量,它实际上存在于宇宙只有约 7 亿年的历史,是其当前 138 亿年年龄的一小部分。这是一个令人费解的问题结果,因为在这么早的时候,根据标准理论,还没有足够的时间来发展如此巨大的黑洞。已经提出了一些方案来解决这个谜团。

一种可能性是,由早期宇宙中第一代恒星的死亡引起的黑洞以异常高的速度积累物质。 另一种情况是,尚未富含比氦重的化学元素的原始气体云可以直接坍缩形成[{” attribute=””>black hole with a mass of a few hundred thousand solar masses, and subsequently accrete matter to evolve into the hyper-massive black holes observed at later epochs. Finally, dense, nuclear star clusters at the centers of baby galaxies may have produced intermediate mass black hole seeds, via stellar collisions or merging of stellar-mass black holes, and then become much more massive via accretion.

Populations of Known Black Holes in Early Universe

This illustration shows the populations of known black holes (large black dots) and the candidate black hole progenitors in the early universe (shaded regions). Credit: Roberto Maiolino, University of Cambridge

“Webb is about to open a completely new discovery space in this area. It is possible that the first black hole seeds originally formed in the ‘baby universe,’ within just a few million years after the big bang. Webb is the perfect ‘time machine’ to learn about these primeval objects. Its exceptional sensitivity makes Webb capable of detecting extremely distant galaxies, and because of the time required for the light emitted by the galaxies to travel to us, we will see them as they were in the remote past.

“Webb’s NIRSpec instrument is particularly well suited to identify primeval black hole seeds. My colleagues in the NIRSpec Instrument Science Team and I will be searching for their signatures during ‘active’ phases, when they are voraciously gobbling matter and growing rapidly. In these phases the material surrounding them becomes extremely hot and luminous and ionizes the atoms in their surroundings and in their host galaxies.

“NIRSpec will disperse the light from these systems into spectra, or ‘rainbows.’ The rainbow of active black hole seeds will be characterised by specific ‘fingerprints,’ features of highly ionized atoms. NIRSpec will also measure the velocity of the gas orbiting in the vicinity of these primeval black holes. Smaller black holes will be characterized by lower orbital velocities. Black hole seeds formed in pristine clouds will be identified by the absence of features associated with any element heavier than helium.

“I look forward to using Webb’s unprecedented capabilities to search for these black hole progenitors, with the ultimate goal of understanding their nature and origin. The early universe and the realm of black holes seeds is a completely uncharted territory that my colleagues and I are very excited to explore with Webb.”

Roberto Maiolino, professor of experimental astrophysics and director of the Kavli Institute for Cosmology, University of Cambridge

Written by:

  • Jonathan Gardner, Webb deputy senior project scientist, NASA’s Goddard Space Flight Center
  • Stefanie Milam, Webb deputy project scientist for planetary science, NASA’s Goddard Space Flight Center
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