# Splashback in accreting dark matter halos

**Authors:** Susmita Adhikari, Neal Dalal, Robert T. Chamberlain  
**arXiv:** [1409.4482](https://arxiv.org/abs/1409.4482)  
**Date:** 2014-09-16  
**Summary page:** https://www.summarizepaper.com/en/paper/1409.4482v1/

## Key points

- Recent research has discovered a steep density profile behavior in the outskirts of dark matter halos.
- This behavior is caused by splashback material during the first apocentric passage after accretion.
- Adhikari, Dalal, and Chamberlain present a model that accurately predicts the location of this splashback feature without any free parameters.
- The authors use a model based on spherical collapse to determine the position of the splashback without adjustable factors.
- The rate of matter accretion onto dark matter halos and redshift are identified as key factors in determining the radius at which splashback occurs.
- This study provides valuable insights into understanding density profiles within dark matter halos.
- The authors' approach using spherical collapse modeling offers a robust framework for studying and predicting splashback phenomena without unnecessary complexities or uncertainties.

## Summary

Recent research has revealed an intriguing phenomenon in the outskirts of dark matter halos: density profiles can exhibit a remarkably steep behavior over a narrow range of radius. This peculiar feature is attributed to the presence of splashback material, which occurs during the first apocentric passage after accretion. In this study, Adhikari, Dalal, and Chamberlain present a simple yet effective model that accurately predicts the location of this splashback feature without relying on any free parameters. The authors demonstrate that the position of the splashback can be understood from fundamental principles by employing a model based on spherical collapse. They successfully determine the precise location of the splashback without requiring any additional adjustable factors. The key determinants for establishing the radius at which splashback occurs are identified as the rate at which matter is accreted onto dark matter halos and redshift. This refined summary provides valuable insights into recent advancements in understanding density profiles within dark matter halos. The authors' straightforward approach using spherical collapse modeling offers a robust framework for predicting and studying splashback phenomena without introducing unnecessary complexities or uncertainties.