Silk damping in scalar-induced gravitational waves: a novel probe for new physics

作     者：Yan-Heng Yu Sai Wang 

作者机构：Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences School of Physics University of Chinese Academy of Sciences 

出 版 物：《Science China(Physics,Mechanics & Astronomy)》 (中国科学:物理学 力学 天文学(英文版))

年 卷 期：2024年

核心收录：

学科分类：07[理学] 070401[理学-天体物理] 0704[理学-天文学] 

基　　金：supported by the National Natural Science Foundation of China (Grant No. 12175243) the National Key R&D Program of China (Grant No. 2023YFC2206403) the Science Research Grants from the China Manned Space Project (Grant No. CMS-CSST-2021-B01) the Key Research Program of the Chinese Academy of Sciences (Grant No. XDPB15) 

摘      要：Silk damping is well known in the study of cosmic microwave background（CMB） and accounts for suppression of the angular power spectrum of CMB on large angular multipoles. In this article, we study the effect of Silk damping on the scalar-induced gravitational waves（SIGWs）. Resulting from the dissipation of cosmic fluid, the Silk damping notably suppresses the energydensity spectrum of SIGWs on scales comparable to a diffusion scale at the decoupling time of weakly-interacting particles. The effect offers a novel observable for probing the underlying particle interaction, especially for those mediated by heavy gauge bosons beyond the standard model of particles. We anticipate that pulsar timing arrays are sensitive to gauge bosons with mass ～ 10～3-10～4GeV, while space-and ground-based interferometers to those with mass ～ 10～7-1012GeV, leading to essential complements to on-going and future experiments of high-energy physics.