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Toward a universal formulation of the halo mass function
1Laboratoire Univers et Théories (LUTh), UMR 8102 CNRS, Observatoire de Paris, Université Paris Diderot, Meudon, France.
Physical Review Letters
|July 21, 2011
Summary
We accurately calculated the dark matter halo mass function using advanced excursion set methods. Our findings show excellent agreement with simulation data, improving dark matter halo predictions.
Area of Science:
- Cosmology
- Astrophysics
- Computational Physics
Background:
- The dark matter halo mass function is crucial for understanding cosmic structure formation.
- Previous models often simplified the complex physics of halo collapse.
Purpose of the Study:
- To compute the dark matter halo mass function with improved accuracy.
- To incorporate realistic ellipsoidal collapse physics into theoretical models.
Main Methods:
- Utilized the excursion set formalism with a diffusive barrier and linearly drifting average.
- Employed a path-integral method to evaluate non-Markovian corrections from sharp filtering.
- Compared results with extensive N-body simulation data.
Main Results:
- Achieved unprecedented agreement with N-body simulation data.
- Deviations were less than 5% across the probed mass range.
- The model accurately captures key features of ellipsoidal collapse.
Conclusions:
- The excursion set formalism, with realistic collapse modeling, provides a robust estimation of the halo mass function.
- This approach offers a significant improvement over previous theoretical predictions.
- The findings enhance our understanding of dark matter distribution in the universe.
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