Theory HEP Seminar

Probing gas distribution with gravitational lensing and CMB maps

Yin-Zhe Ma

University of British Columbia

Previous studies of galaxy formation have shown that only 10 per cent of the baryons are in compact objects, while 90 per cent of them are missing. Numerical simulation shows that the missing baryons are in a state of diffuse plasma with temperature 10⁵ to 10⁷ Kevlin, which is hard to be detected by X-ray observations. In this talk, we present a thermal Sunyaev- Zeldovich-Lensing cross-correlation (from the Canada France Hawaii Lensing Survey (CFHTLenS) and Planck's thermal Sunyaev Zeldovich maps), and constrain the diffuse baryon component with the various pressure profile. We find that the 1 and 2 halo terms detected at 3.96σ and 3.67σ confidence level (CL) respectively. The effective virial temperature of the isothermal gas is found to be in the range 7×10⁵-3×10⁸ K. In addition, by stacking the pairs of luminous red galaxies, we can place a constraint on the temperature of the filament in between the dark matter halos.