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arXiv · 2604.05472

Multiquark clustering in neutron-star matter from color-spin molecular dynamics

Nobutoshi Yasutake·Yuta Mukobara·Aaron Park·Su Houng Lee·Toshiki Maruyama
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Abstract

We study the equation of state of neutron-star matter with color-spin molecular dynamics. The calculation includes the internal color and spin degrees of freedom and their time evolution. The matter composition, including strangeness under $\beta$ equilibrium, is determined by energy minimization. We find two main trends. First, within the present color-spin molecular dynamics framework and under the adopted clustering criterion along the stable neutron-star branch, isolated quarklike configurations do not appear; instead, color-magnetic interactions favor the self-consistent formation of multiquark clusters. Within the same criterion, the cluster-size distribution is concentrated at quark numbers that are multiples of three, corresponding to integer baryon numbers. Second, relative to the conventional no-$K^*$ baseline, the interaction between strange and light quarks has a strong impact on neutron-star radii. This suggests that future radius measurements, together with phenomenological information on the strangeness-onset density, may help constrain flavor-sector interactions involving strangeness.

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Nobutoshi Yasutake, Yuta Mukobara, Aaron Park, Su Houng Lee, Toshiki Maruyama. 2026-04-07. Multiquark clustering in neutron-star matter from color-spin molecular dynamics. https://arxiv.org/abs/2604.05472

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