The New Dark Matter Density Profile from JWST JADES Galaxies
Abstract
We present the first dark matter density profile derived directly from James Webb Space Telescope JADES Data Release~3 NIRSpec observations of N = 587 galaxies spanning the cosmic noon epoch 1.5 ≤ z ≤ 3.5. From each NIRSpec G235M/G395M spectrum we extract the Hα emission-line velocity dispersion σha, stack galaxies in four redshift bins of Δz = 0.5, and reconstruct representative group rotation curves within the General Theory of Relativity. Fitting the four-parameter modified exponential model and deriving the exact GTR energy density, we reduce the profile to a compact [2/3] Padé approximant with all coefficients determined in closed form from JWST observations. The profile is cusp-free, fully analytic, and redshift-dependent. Energy conditions, causality, and orbital stability are all satisfied. Most strikingly, the central density ρ(0) varies by less than 15% across z = 1.5--$3.5$ despite a 35% decline in the asymptotic rotation velocity, revealing a universal dark matter core saturation density at cosmic noon decoupled from baryonic evolution.
Related
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- Cosmological extra dimensions can mimic dark matter I. Dark matter in galaxies
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BibTeX
@misc{sanyal2026dark,
title = {{The New Dark Matter Density Profile from JWST JADES Galaxies}},
author = {Aritra Sanyal and Farook Rahaman},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2609.14071},
eprint = {2609.14071},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.14071},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - The New Dark Matter Density Profile from JWST JADES Galaxies
AU - Aritra Sanyal
AU - Farook Rahaman
PY - 2026
DA - 2026/10/06
PB - arXiv
DO - 10.48550/arxiv.2609.14071
UR - https://arxiv.org/abs/2609.14071
AB - We present the first dark matter density profile derived directly from James Webb Space Telescope JADES Data Release~3 NIRSpec observations of N = 587 galaxies spanning the cosmic noon epoch 1.5 ≤ z ≤ 3.5. From each NIRSpec G235M/G395M spectrum we extract the Hα emission-line velocity dispersion σ_ha, stack galaxies in four redshift bins of Δz = 0.5, and reconstruct representative group rotation curves within the General Theory of Relativity. Fitting the four-parameter modified exponential model and deriving the exact GTR energy density, we reduce the profile to a compact [2/3] Padé approximant with all coefficients determined in closed form from JWST observations. The profile is cusp-free, fully analytic, and redshift-dependent. Energy conditions, causality, and orbital stability are all satisfied. Most strikingly, the central density ρ(0) varies by less than 15% across z = 1.5--$3.5$ despite a 35% decline in the asymptotic rotation velocity, revealing a universal dark matter core saturation density at cosmic noon decoupled from baryonic evolution.
ER -