利用FAST寻找奇异夸克集团星证据

It is challenging us to understand the equation of state of dense matter at supra-nuclear density in both astronomy and physics. One can neither solve the problem from the first principles due to non-perturbative behavior of the strong interaction at low energy scale, nor constrain the state by the present observations. In fact, it is a key science to test different models of pulsar interior for advanced telescopes, either on ground or in space. Aimed at difficulties and problems in the standard model of pulsar, we addressed that pulsars could be strange quark-cluster stars (simply strange stars) according to our pulsar researches. Although this idea could be consistent with various kinds of observations, it is very necessary to test further. As the economic development, China starts to build large astronomical telescopes, including the five hundred meters aperture spherical radio telescope (FAST). These provide an excellent opportunity to examine the state of dense matter, hopefully discovery evidence for strange star. We are proposing to find evidence for strange star with FAST in this project. The research is both theoretical and observational, including measurements of pulsar mass and moment of inertia, discovery of sub-millisecond pulsar, pulse profile and magnetospheric activity, etc. The group members have professional background of theoretical and observational researches, as well as friendly personal relations to FAST science group, that are helpful to obtain perfect scientific results.

揭示极致密物质状态是天文和物理领域一大挑战。此致密物态因涉及低能强作用非微扰行为而不能从第一性原理计算给出，亦不能被已有观测完全限制。如何观测检验各类脉冲星结构模型属于地面或空间大型望远镜的核心科学。我们针对流行理论框架内存在的疑难问题，在脉冲星研究基础上曾提出脉冲星类天体为奇异夸克集团星（简称奇异星）。尽管该看法在诸多方面与观测不矛盾，但尚有待进一步地观测验证。随着经济实力的提升，我国也着手建设包括五百米球面射电望远镜（FAST）在内地大型先进设备。这为我们认识致密物质状态提供了难得的机遇，并有望最终找到奇异星存在的切实证据。本项目建议利用FAST监测和发现射电脉冲星来寻找奇异星证据。研究工作从观测和理论两方面开展，包括质量和转动惯量测量、发现亚毫秒脉冲星、通过脉冲轮廓研究磁层活动性等方面。研究队伍有较好的理论和观测研究背景，并一直跟FAST科学团队友好地沟通与合作，预期可取得理想成果。

略高于核密度的中子星物质的构成及状态，涉及基本强作用的低能非微扰行为，是当今中高能核物理面临的疑难之一，也可能是包括引力波在内的多信使天文学时代拟根本解决的首个重大科学问题。项目负责人认为这类致密星的基本单元并非中子而是奇子。本课题进一步研究奇子星的物态及其若干天体物理表现，并期望寻找FAST望远镜观测方面的可能证据。研究成果包括：利用FAST观测研究PSR B2016+28的单脉冲，结合FAST观测研究FRB重复暴的起源与辐射，在奇子星框架下理解glitch的活跃性并期待未来SKA和FAST等观测检验，等等。项目执行期间培养了一批优秀的博士生，项目成员也以论文、演讲或网站等形式积极向公众宣传天文最新成果。