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تسجيل مستخدم جديدPhotometric Evolution of Galaxies in Cosmological Scenarios
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The photometric evolution of galaxies in a hierarchically clustering universe is investigated. The study is based on high resolution numerical simulations which include the effects of gas dynamics, shock heating, radiative cooling and a heuristic star formation scheme. The outcome of the simulations is convolved with photometric models which enables us to predict the appearance of galaxies in the broad band colors U, B, V, R, I and K. We demonstrate the effect of the mutual interplay of the hierarchical build-up of galaxies, photometric evolution, k-correction, and intervening absorption on the appearance of forming disk galaxies at redshift one to three. We also discuss to what extend the numerical resolution of current computer simulations is sufficient to make quantitative predictions on surface density profiles and color gradients.
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