Primordial Black holes and Modification of Zeldovich-Novikov Mechanism

利用动力学 Sunyaev-Zeldovich 效应进行三维速度重建对局部原初非高斯性的约束

Constraints on local primordial non-Gaussianity with 3d Velocity Reconstruction from the Kinetic Sunyaev-Zeldovich Effect

本研究首次利用动力学 Sunyaev-Zeldovich 效应结合 CMB 和星系数据实现大尺度速度场三维重建，探测到星系-速度交叉信号，并据此对局部原初非高斯性幅度进行了约束，为未来提升该参数的测量精度奠定了基础。

The Thermal Sunyaev-Zeldovich Effect of Primordial Recombination Radiation

It is well known that recombination radiation of primordial hydrogen-helium plasma leads to the distortions of the planckian spectrum shape of the cosmic microwave background radiation (CMB). We discuss the thermal Sunyaev-Zeldovich (SZ) effect with taking into account primordial recombination radiation (PRR). Since in the thermal SZ effect the redistribution of the photons depends on the derivatives of the spectrum, the value of relative correction to SZ effect due to PRR significantly higher than relative corrections due to PRR in the initial spectrum. Calculations of corrections to the ther…

Kinetic Sunyaev Zeldovich effect in an anisotropic CMB model: measuring low multipoles of the CMB at higher redshifts using intensity and polarization spectral distortions

We present a novel mathematical formalism that allows to easily compute the expected kinetic Sunyaev Zeldovich (kSZ) signal in intensity and polarization due to an anisotropic primordial Cosmic Microwave Background (CMB). We derive the expected intensity and polarization distortions in the direction of non-moving galaxy clusters and then we generalize our calculations for non-zero peculiar velocity. We show that, in the direction of moving clusters, low CMB multipoles impose intensity and polarization spectral distortions with different frequency dependences. The polarization signal primarily …

利用热Sunyaev-Zeldovich效应与积分Sachs-Wolfe效应的交叉关联约束原初非高斯性与能量注入

Constraining primordial non-Gaussianity and energy injection with the thermal Sunyaev-Zeldovich effect and integrated Sachs-Wolfe effect cross-correlation

本研究利用ISW与tSZ效应的交叉关联，联合约束原初非高斯性与早期宇宙能量注入，相关约束与Planck先验结合可降低不确定度，未来巡天将进一步提升约束精度。

Constraints on Non-Gaussianity from Sunyaev--Zeldovich Cluster Surveys

We perform a Fisher matrix analysis to forecast the capability of ongoing and future Sunyaev-Zeldovich cluster surveys in constraining the deviations from Gaussian distribution of primordial density perturbations. We use the constraining power of the cluster number counts and clustering properties to forecast limits on the $\fnl$ parameter. The primordial non-Gaussianity effects on the mass function and halo bias are considered. We adopt self-calibration for the mass-observable scaling relation, and evaluate constraints for the SPT, Planck, CCAT--like, SPTPol and ACTPol surveys. We show that t…

Helium abundance in galaxy clusters and Sunyaev-Zeldovich effect

It has long been suggested that helium nuclei in the intracluster plasma can sediment in the cluster gravitational potential well. Some theoretical estimates for the cores of relaxed clusters predict an excess of helium abundance by up to a factor of a few over its primordial value. The intracluster helium abundance cannot be measured directly. This presents a significant source of uncertainty for cosmological tests based on the X-ray derived cluster quantities, such as the gas mass, total mass, and gas mass fraction, all of which depend on the assumed helium abundance. We point out that clust…