Oct 1

"The Kinetic Sunyaev-Zel'dovich effect as the Probe of the Reionization Epoch"
Hyunbae Park, University of Texas at Austin

We present a calculation of the angular power spectrum of the Cosmic Microwave Background (CMB) fluctuation induced by the kinetic Sunyaev-Zel'dovich effect from the reionization era. We use our N-body+radiative transfer simulations to model the inhomogeneity of the reionization. We first show that the inhomogeneity boosts the signal by an order of magnitude with the maximum contribution from the epoch, which the typical size of the bubble matches the angular scale of the fluctuation. Then, we examine the impact on the kSZ signal of the "self-regulation" of reionization, which results if low-mass dwarf galaxies or mini halos are suppressed as sources of reionization if they form in regions that were already ionized or Lyman-Werner dissociated. Those self-regulating sources accelerates reionization process in the early time significantly while get shut off at late time. Those self-regulated sources does not change the CMB fluctuation power induced by the kSZ signal at l=3000 much, but significantly enhances the power at higher l's. This cautions simple parametrization of the induced CMB fluctuation power at l=3000 by Zahn et al. 2011 and Mesinger et al. 2011. kSZ signal from our models satisfy the observational upper bound provided by the South Pole Telescope measurement.