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تسجيل مستخدم جديدDust entrainment in photoevaporative winds: The impact of X-rays
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X-ray- and EUV- (XEUV-) driven photoevaporative winds acting on protoplanetary disks around young T-Tauri stars may crucially impact disk evolution, affecting both gas and dust distributions. We investigate the dust entrainment in XEUV-driven photoevaporative winds and compare our results to existing MHD and EUV-only models. For an X-ray luminosity of $L_X = 2 cdot 10^{30},mathrm{erg/s}$ emitted by a $M_* = 0.7,mathrm{M}_odot$ star, corresponding to a wind mass-loss rate of $dot{M}_mathrm{w} simeq 2.6 cdot 10^{-8} ,mathrm{M_odot/yr}$, we find dust entrainment for sizes $a_0 lesssim 11,mu$m ($9,mu$m) from the inner $25,$AU ($120,$AU). This is an enhancement over dust entrainment in less vigorous EUV-driven winds with $dot{M}_mathrm{w} simeq 10^{-10},mathrm{M_odot/yr}$. Our numerical model also shows deviations of dust grain trajectories from the gas streamlines even for $mu$m-sized particles. In addition, we find a correlation between the size of the entrained grains and the maximum height they reach in the outflow.
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