اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدA Redefinition of the Halo Boundary Leads to a Simple yet Accurate Halo Model of Large Scale Structure
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We present a model for the halo--mass correlation function that explicitly incorporates halo exclusion. We assume that halos trace mass in a way that can be described using a single scale-independent bias parameter. However, our model exhibits scale dependent biasing due to the impact of halo-exclusion, the use of a ``soft (i.e. not infinitely sharp) halo boundary, and differences in the one halo term contributions to $xi_{rm hm}$ and $xi_{rm mm}$. These features naturally lead us to a redefinition of the halo boundary that lies at the ``by eye transition radius from the one--halo to the two--halo term in the halo--mass correlation function. When adopting our proposed definition, our model succeeds in describing the halo--mass correlation function with $approx 2%$ residuals over the radial range $0.1 h^{-1}{rm Mpc} < r < 80 h^{-1}{rm Mpc}$, and for halo masses in the range $10^{13} h^{-1}{rm M}_{odot} < M < 10^{15} h^{-1}{rm M}_{odot}$. Our proposed halo boundary is related to the splashback radius by a roughly constant multiplicative factor. Taking the 87-percentile as reference we find $r_{rm t}/R_{rm sp} approx 1.3$. Surprisingly, our proposed definition results in halo abundances that are well described by the Press-Schechter mass function with $delta_{rm sc}=1.449pm 0.004$. The clustering bias parameter is offset from the standard background-split prediction by $approx 10%-15%$. This level of agreement is comparable to that achieved with more standard halo definitions.
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