Conveners
06 - 引力波理论与实验
- YU QING LOU (清华大学 物理系)
06 - 引力波理论与实验
- Ziren Luo
我们精确研究相变动力学，并通过相变动力学过程得到新的暗物质产生机制。同时，我们给出了这类相变动力学暗物质的引力波信号。
LISA, Taiji, and TianQin are scheduled to observe milli-Hz gravitational waves (GWs) in space. Their target sources include massive black hole binary (MBHB) coalescences, galactic binaries, extreme mass ratio inspirals, and astrophysical and cosmological stochastic gravitational wave backgrounds. Observing MBHBs with high signal-to-noise ratio will provide unprecedented opportunities to test...
The pulsar timings are sensitive to both the nanohertz gravitational-wave background and the oscillation of ultralight dark matter. The Hellings-Downs angular correlation curve provides a criterion to search for stochastic gravitational-wave backgrounds at nanohertz via pulsar timing arrays. We study the angular correlation of the timing residuals induced by the spin-2 ultralight dark matter,...
Recently, Pulsar Timing Array collaborations have discovered strong evidence of the nanohertz gravitational wave background. This has sparked extensive discussions in the academic community regarding the sources of gravitational waves, with strong interest in cosmological sources in addition to supermassive black holes. This report will focus on the progress of scalar-induced gravitational...
The concept of early Universe inflation resolves several problems of hot Big Bang theory and quantitatively explains the origin of the inhomogeneities in the present Universe. However, it is not possible to arrange inflation in a scalar field model with renormalizable potential, such that it would not contradict the recent Planck data. For this reason, an effective field theory approach must...
太极计划是中国科学院发起的空间引力波探测计划，目标频率范围为0.1mHz-1Hz。利用激光差分干涉技术将测试质量间的距离变化信息转换为相位变化，通过对相位的高精度测量达到对位移的高精度测量目的。太极计划对测量的要求为在300万公里的距离上，位移测量精度需达到pm量级。激光器采用是Nd:YAG超窄线宽固体激光器，波长1064nm。要达到1pm的测距精度，相位测量要求为2πμrad/√Hz。本次报告将介绍太极计划激光干涉仪的原理、构成、关键技术及研究现状。主要包括太极一号激光干涉系统在轨结果，太极计划现阶段干涉仪光学平台、相位计、捕获指向等发展现状。作为国内首颗空间引力波探测卫星，太极一号实现了在轨30pm/√Hz的测距精度。为进一步的提高测量精度，为今后的太极计划奠定技术基础。干涉仪光学平台目前采用微晶玻璃和熔融石英，粘接方式采用NaOH催化粘接的方式。激光干涉仪测量精度在10mHz-...
针对空间引力波探测“太极”计划，梳理了科学载荷集成测试过程中的难点与关键技术。介绍了基于MOSA和TCA为核心的载荷集成测试方案，以及已建立和正在筹建的相应集成测试平台。另外，针对载荷地面集成测试过程中科学载荷间的耦合以及相应的测试技术也进行了部分介绍。
中低频空间引力波探测对航天器入轨精度、温度波动、振动、微变形、自引力、磁扰动等都极为敏感。为有效抑制载荷受到的外部干扰，给仪器提供良好的工作环境，开展了航天器小推力轨道转移设计、超稳结构设计、自引力总体设计与控制、星载温度精密调控、超高磁洁净设计与控制以及多参考质量非正交无拖曳控制等技术研究，提出了连续小推力与高精度模型等组合的轨道转移全局优化、多级阻尼高稳定温控、基于社会学习因子筛选粒子群的磁特性反演、噪声传播建模与多回路解耦、多源扰动抑制鲁棒控制等系列方法，并在地面进行了技术仿真或试验验证。结果表明，航天器轨道、结构、热、磁、自引力和无拖曳控制性能可以满足引力波探测需求。
