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تسجيل مستخدم جديدCMB Anisotropies due to Feedback-Regulated Inhomogeneous Reionization
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We calculate the secondary anisotropies in the CMB produced by inhomogeneous reionization from simulations in which the effects of radiative and stellar feedback effects on galaxy formation have been included. This allows to self-consistently determine the beginning ($z_iapprox 30$), the duration ($ delta zapprox 20$) and the (nonlinear) evolution of the reionization process for a critical density CDM model. In addition, from the simulated spatial distribution of ionized regions, we are able to calculate the evolution of the two-point ionization correlation function, $C_chi$, and obtain the power spectrum of the anisotropies, $C_ell$, in the range $5000 < ell < 10^6$. The power spectrum has a broad maximum around $ell approx 30000$, where it reaches the value $2times 10^{-12}$. We also show that the angular correlation function $C(theta)$ is not Gaussian, but at separation angles $% theta lower.5exhbox{ltsima} 10^{-4}$ rad it can be approximated by a modified Lorentzian shape; at larger separations an anticorrelation signal is predicted. Detection of signals as above will be possible with future mm-wavelength interferometers like ALMA, which appears as an optimum instrument to search for signatures of inhomogeneous reionization.
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