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arXiv · 2602.13688

Pulsars and Millisecond Pulsars III: Tracing Compact Object Dynamics in Globular Clusters with NBODY6++GPU

M. Rah·R. Spurzem·F. Flammini Dotti·A. Mickaelian
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Abstract

Neutron stars in globular clusters follow complex evolutionary pathways shaped by binary interactions, mass transfer, and dynamical exchanges. Direct N-body simulations such as NBODY6++GPU successfully model stellar dynamics and compact object formation, but they usually do not track pulsar spin evolution or magnetic field decay explicitly. Building on Papers I and II of this series, we identify this gap and present a case study from an existing simulation with N = 105000 particles, showing how a neutron star forms and evolves for 200 Myr without any pulsar-physics tracking. We compare this situation with recent implementations and outline a seven-scenario framework that includes magnetic dipole spin-down, exponential magnetic field decay, environmental torques, accretion-driven spin-up, gravitational-wave emission, and merger-driven evolution. As an example, the neutron star we label Pulsar973 forms at t = 800 Myr with a post-supernova mass of 5.35 solar masses and evolves to 2.52 solar masses by t = 1000 Myr, but still lacks period P, period derivative Pdot, magnetic field B, and scenario classification. We provide mathematical formulations and specific integration points within NBODY6++GPU (Hermite scheme, Ahmad-Cohen neighbors, KS regularization, and BSE stellar evolution) to enable scenario-based pulsar evolution within direct N-body simulations.

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M. Rah, R. Spurzem, F. Flammini Dotti, A. Mickaelian. 2026-02-14. Pulsars and Millisecond Pulsars III: Tracing Compact Object Dynamics in Globular Clusters with NBODY6++GPU. https://doi.org/10.52526/25792776-25.72.2-279

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