Connecting Astrophysics and Fundamental Physics

连接天体物理学和基础物理学

• 批准号: RGPIN-2017-03756
• 负责人: Heyl, Jeremy
• 金额: $ 3.35万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=653521
• 关键词: Connecting; Astrophysics; Fundamental; Physics

The astrophysics of stars and compact objects (neutron stars, white dwarfs and black holes) constrain fundamental physics in crucial and unique ways. Furthermore, over the past several years astronomers and physicists have opened two new windows onto the Universe: gravitational radiation and neutrinos. In the near future astronomers will be able to probe the Universe with x-ray polarimetry. I propose several lines of research that exploit these unique and timely opportunities. In particular I propose a series of studies to probe the properties of weakly interacting particles in stars in globular clusters: both theoretical and observational investigations. Second I propose to develop techniques to constrain the neutron star equation of state using a combination of x-ray polarimetry, timing and spectroscopy including the effects of QED birefringence that produces unique signatures on the polarization of x-ray radiation from neutron stars. The third direction is gravitational. In particular I will explore how electromagnetic observations can best probe the properties of accreting black holes.******Our recent studies of the stellar populations in the core of 47 Tucanae demonstrate how a holistic approach to modelling the data can reap great rewards. Specifically we model the evolution of the stars in the cluster including stellar evolution, dynamics and atmospheres starting from the fundamental physical equations all the way to a prediction of the observed data including the observational biases. To obtain constraints on the underlying physics we have to constrain the astrophysical uncertainties, so we simulate the entire evolution of a star from the main sequence to the oldest white dwarfs and use observations and models of the entire process. We now have similar data for over 50 other globular clusters so we can further mitigate the astrophysical uncertainties by studying the stars in a variety of environments.******Observations of x-ray polarization from neutron stars and black holes will providing estimates of their structure and the magnetic fields that surround these objects. I propose to develop theoretical models of the emission regions of x-ray pulsars (that haven't be updated since the eighties) and the magnetic fields surrounding black holes. The goal is to bring the theoretical models all the way to the observational realm to predict the observed distribution of photon energies, polarization directions and arrival times to understand these objects in the greatest detail.

恒星和致密天体(中子星、白矮星和黑洞)的天体物理学以至关重要和独特的方式制约着基础物理学。此外，在过去的几年里，天文学家和物理学家打开了两扇通往宇宙的新窗口：引力辐射和中微子。在不久的将来，天文学家将能够用X射线偏振测量法探测宇宙。我提出了几条研究路线，以利用这些独特和及时的机会。特别是，我提出了一系列研究，以探索球状星团中恒星中弱相互作用粒子的性质：包括理论和观测调查。其次，我建议开发一种技术来约束中子星的状态方程，使用x射线偏振、计时和光谱学的组合，包括QED双折射的影响，它在中子星的x射线辐射的极化上产生独特的信号。第三个方向是引力。特别是，我将探索电磁观测如何最好地探索吸积黑洞的性质。*我们最近对47个图卡纳核心的恒星种群的研究表明，对数据进行整体建模的方法可以获得巨大的回报。具体地说，我们对星系团中恒星的演化进行建模，包括恒星演化、动力学和大气，从基本物理方程一直到包括观测偏差在内的观测数据的预测。为了获得对基本物理的约束，我们必须约束天体物理的不确定性，所以我们模拟了恒星从主序到最古老的白矮星的整个演化过程，并使用整个过程的观测和模型。我们现在有超过50个其他球状星团的类似数据，所以我们可以通过研究不同环境中的恒星来进一步减轻天体物理上的不确定性。对中子星和黑洞的x射线偏振的观测将提供对它们结构和围绕这些天体的磁场的估计。我建议建立x射线脉冲星的发射区(自80年代以来就没有更新过)和黑洞周围磁场的理论模型。其目标是将理论模型一路带到观测领域，以预测观测到的光子能量分布、偏振方向和到达时间，以最详细地了解这些物体。