Dark Matter-Baryon Separability Predicts the Dynamics of an Almost-Dark Galaxy
Abstract
We extend the Dark Matter-Baryon Separability Condition to show that the same framework developed for dark matter deficient galaxies naturally admits a conjugate branch describing preferential baryonic depletion. Using the recently discovered almost-dark galaxy TTT J1237327+143535 as a worked example, we derive a family of dynamical consistency relations parameterized by the unknown progenitor ratio μi, including thresholds for σlos, Mdyn, the enclosed baryonic fraction and the dynamical mass to light ratio. We further connect the separability framework to the expected globular cluster population, providing an independent consistency test of the inferred halo mass. We also provide some bounds on the baryon ratio using the tidal properties of Virgo Cluster. Future measurements of stellar kinematics, gas content and globular clusters can therefore determine whether this galaxy occupies the positive separability branch and also test whether dark matter deficient and baryon depleted systems can be described within a common framework.
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BibTeX
@misc{trivedi2026dark,
title = {{Dark Matter-Baryon Separability Predicts the Dynamics of an Almost-Dark Galaxy}},
author = {Oem Trivedi and Abraham Loeb},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.10661},
eprint = {2609.10661},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.10661},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Dark Matter-Baryon Separability Predicts the Dynamics of an Almost-Dark Galaxy
AU - Oem Trivedi
AU - Abraham Loeb
PY - 2026
DA - 2026/09/09
PB - arXiv
DO - 10.48550/arxiv.2609.10661
UR - https://arxiv.org/abs/2609.10661
AB - We extend the Dark Matter-Baryon Separability Condition to show that the same framework developed for dark matter deficient galaxies naturally admits a conjugate branch describing preferential baryonic depletion. Using the recently discovered almost-dark galaxy TTT J1237327+143535 as a worked example, we derive a family of dynamical consistency relations parameterized by the unknown progenitor ratio μ_i, including thresholds for σ_los, M_dyn, the enclosed baryonic fraction and the dynamical mass to light ratio. We further connect the separability framework to the expected globular cluster population, providing an independent consistency test of the inferred halo mass. We also provide some bounds on the baryon ratio using the tidal properties of Virgo Cluster. Future measurements of stellar kinematics, gas content and globular clusters can therefore determine whether this galaxy occupies the positive separability branch and also test whether dark matter deficient and baryon depleted systems can be described within a common framework.
ER -