Prompt cusps delay core formation by a factor of ~2 in SIDM halos but later collapse tracks align after rescaling, with ~5% late-stage deviations depending on concentration and outer velocity dispersion.
The overconcentrated dark halo in the strong lens SDSS J0946+1006 is a sub- halo: evidence for self interacting dark matter?
6 Pith papers cite this work. Polarity classification is still indexing.
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Pith papers citing it
abstract
The nature of dark matter is poorly constrained on subgalactic scales. Alternative models to cold dark matter, such as warm dark matter or self-interacting dark matter, could produce very different dark haloes on these scales. One of the few known dark haloes smaller than a galaxy was discovered in the triple source plane strong lens system J0946+1006. Previous studies have found that this structure is much more concentrated than expected in $\Lambda$CDM, but have assumed the dark halo is at the same redshift as the main deflector ($z_{\rm main}=0.222$). In this paper, we fit for the redshift of this dark halo. We reconstruct the first two sources in the system using a forward modelling approach, allowing for additional complexity from multipole perturbations. We find that the perturber redshift is $z_{\rm halo} = {0.207}^{+0.019}_{-0.019}$, and lower bounds on the evidence strongly prefer a subhalo over a line-of-sight structure. Whilst modelling both background sources does not improve constraints on the redshift of the subhalo, it breaks important degeneracies affecting the reconstruction of multipole perturbations. We find that the subhalo is a more than $5\sigma$ outlier from the $\Lambda$CDM $v_{\rm max}$-$r_{\rm max}$ relation and has a steep profile with an average slope of $\gamma_{\rm 2D} = {-1.81}^{+0.15}_{-0.11}$ for radii between $0.75-1.25$ kpc. This steep slope might indicate dark matter self-interactions causing the subhalo to undergo gravothermal collapse; such collapsed haloes are expected to have $\gamma_{\rm 2D} \approx -2$.
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JWST lensing data on 28 systems constrain dark matter free-streaming length to below 6-7 kpc and thermal relic mass above 6.5-7.4 keV, consistent with cold dark matter predictions.
Two-component SIDM with velocity-dependent inter- and intra-species interactions produces mass segregation that forms dwarf cores and boosts small-scale strong lensing efficiency by a factor of a few.
Composite time-delay lens modelling of JWST WFI2033–4723 yields intermediate stellar IMF normalisation and a steep gNFW inner slope γ_in≃1.3 that is robust to the choice of external cosmology.
MW-mass SIDM halos bypass core formation and enter immediate core collapse due to baryonic preconditioning, allowing the compact stellar disk and bulge to survive close pericenter passages while the diffuse halo is more easily disrupted.
Baryonic feedback mildly delays but does not stall gravothermal collapse in high-concentration SIDM halos and allows resumption in median-concentration cases, yielding feedback-history-dependent central densities.
citing papers explorer
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Role of prompt cusps in driving the core collapse of SIDM halos
Prompt cusps delay core formation by a factor of ~2 in SIDM halos but later collapse tracks align after rescaling, with ~5% late-stage deviations depending on concentration and outer velocity dispersion.
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The free-streaming length of dark matter from JWST observations of 28 strong gravitational lenses
JWST lensing data on 28 systems constrain dark matter free-streaming length to below 6-7 kpc and thermal relic mass above 6.5-7.4 keV, consistent with cold dark matter predictions.
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Self-Interacting Dark Matter with Mass Segregation: A Unified Explanation of Dwarf Cores and Small-Scale Lenses
Two-component SIDM with velocity-dependent inter- and intra-species interactions produces mass segregation that forms dwarf cores and boosts small-scale strong lensing efficiency by a factor of a few.
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Disentangling the dark and stellar mass through precise lens modelling of the JWST observation of lensed quasar WFI2033--4723
Composite time-delay lens modelling of JWST WFI2033–4723 yields intermediate stellar IMF normalisation and a steep gNFW inner slope γ_in≃1.3 that is robust to the choice of external cosmology.
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Bypassed Core Formation in Milky Way-Mass SIDM Halos: Implications for the Local Group Past-Pericenter Scenario
MW-mass SIDM halos bypass core formation and enter immediate core collapse due to baryonic preconditioning, allowing the compact stellar disk and bulge to survive close pericenter passages while the diffuse halo is more easily disrupted.
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Gravothermal Collapse: Robust Against Baryonic Feedback
Baryonic feedback mildly delays but does not stall gravothermal collapse in high-concentration SIDM halos and allows resumption in median-concentration cases, yielding feedback-history-dependent central densities.