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arXiv · 2508.16759

Energy-Space Analysis of Tidal Stripping in Stellar-Dark Matter Systems

Bradley Arias·Nicole E. Drakos·James E. Taylor
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Abstract

Observations reveal a striking diversity in dwarf galaxy structures, spanning a wide range of masses, inner density slopes, shapes, and sizes. Tidal stripping may play a crucial role in shaping the evolution of these galaxies, yet the underlying physical mechanisms remain poorly understood. Using idealized N-body simulations, we investigate the tidal evolution of two-component systems -- stellar and dark matter -- embedded in a host potential. We find that in terms of energy distributions, both stellar and dark matter particles are stripped identically, regardless of their initial profiles. This surprising result suggests that the energy distribution of stripped stars can provide direct constraints on the underlying dark matter structure. Furthermore, we show that systems with cored dark matter and cuspy stellar profiles naturally evolve into dark matter-deficient (DMD) galaxies, supporting tidal stripping as a viable DMD formation pathway. This energy-space analysis of multi-component systems offers new insights into the dynamical evolution of tidally stripped galaxies.

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Bradley Arias, Nicole E. Drakos, James E. Taylor. 2025-08-22. Energy-Space Analysis of Tidal Stripping in Stellar-Dark Matter Systems. https://doi.org/10.33232/001c.168199

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