事件视界成像：超大质量黑洞的亚毫米VLBI
Imaging an Event Horizon: submm-VLBI of a Super Massive Black Hole
摘要：
天体物理学的一个长期目标是直接观察黑洞的直接环境，其角分辨率可与事件视界相媲美。实现这一目标将为强场区域中的广义相对论、黑洞边缘的吸积和流出过程、事件视界的存在以及基本黑洞物理学（例如，自旋）。在改进短波长甚长基线干涉测量能力方面取得的长期稳步进展使这一目标极有可能在未来十年内实现。最令人信服的证据是最近用1.3毫米VLBI观测到SgrA* 中的史瓦西半径尺度结构，SgrA* 是银河系中心的射电、亚毫米波、近红外和x射线的致密源。SgrA* 被认为标记了一个大约400万太阳质量的黑洞的位置，并且由于它的接近和估计的质量，它呈现了宇宙中任何黑洞候选者中最大的明显事件视界尺寸。在接下来的十年里，现有的和计划中的毫米/亚毫米设施将被组合成一个高灵敏度、高角分辨率的“事件视界望远镜”，这将使我们在几十年内尽可能接近黑洞的边缘。本白皮书描述了SgrA* 和M87（一个比SgrA* 更明亮的射电活动星系核）的毫米/亚毫米VLBI观测的科学案例。我们强调，虽然涉及开发和采购，但技术前进的道路是明确的，最近的成功观察消除了通常与这种雄心勃勃的项目有关的大部分风险。
英文摘要：
A long standing goal in astrophysics is to directly observe the immediate environment of a black hole with angular resolution comparable to the event horizon. Realizing this goal would open a new window on the study of General Relativity in the strong field regime, accretion and outflow processes at the edge of a black hole, the existence of an event horizon, and fundamental black hole physics (e.g., spin). Steady long-term progress on improving the capability of Very Long Baseline Interferometry (VLBI) at short wavelengths has now made it extremely likely that this goal will be achieved within the next decade. The most compelling evidence for this is the recent observation by 1.3mm VLBI of Schwarzschild radius scale structure in SgrA*, the compact source of radio, submm, NIR and xrays at the center of the Milky Way. SgrA* is thought to mark the position of a ~4 million solar mass black hole, and because of its proximity and estimated mass presents the largest apparent event horizon size of any black hole candidate in the Universe. Over the next decade, existing and planned mm/submm facilities will be combined into a high sensitivity, high angular resolution "Event Horizon Telescope" that will bring us as close to the edge of black hole as we will come for decades. This white paper describes the science case for mm/submm VLBI observations of both SgrA* and M87 (a radio loud AGN of a much more luminous class that SgrA*). We emphasize that while there is development and procurement involved, the technical path forward is clear, and the recent successful observations have removed much of the risk that would normally be associated with such an ambitious project.
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。
