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ABSTRACT We present a new set of cosmological zoom-in simulations of a Milky Way (MW)-like galaxy that for the first time include elastic velocity-dependent self-interacting dark matter (SIDM) and IllustrisTNG physics. With these simulations, we investigate the interaction between SIDM and baryons and its effects on the galaxy evolution process. We also introduce a novel set of modified dark matter-only simulations that can reasonably replicate the effects of fully realized hydrodynamics on the DM halo while simplifying the analysis and lowering the computational cost. We find that baryons change the thermal structure of the central region of the halo to a greater extent than the SIDM scatterings for MW-like galaxies. Additionally, we find that the new thermal structure of the MW-like halo causes SIDM to create cuspier central densities rather than cores because the SIDM scatterings remove the thermal support by transferring heat away from the centre of the galaxy. We find that this effect, caused by baryon contraction, begins to affect galaxies with a stellar mass of 108 M⊙ and increases in strength to the MW-mass scale.
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This content will become publicly available on November 1, 2026
Sub-GeV Dark Matter Direct Detection with Neutrino Observatories
We present a new technique for sub-GeV dark matter (DM) searches and a new use of neutrino observatories. DM-electron scattering in an observatory can excite or ionize target molecules, which then produce light that can be detected by the photomultiplier tubes (PMTs). While individual DM scatterings are indistinguishable, the aggregate rate from many independent scatterings can be isolated from the total PMT dark rate using the expected DM annual modulation. We showcase this technique with the example of JUNO, a 20 000-ton scintillator detector, showing that its potential sensitivity in some mass ranges exceeds other techniques and reaches key particle-theory benchmarks.
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- Award ID(s):
- 2310018
- PAR ID:
- 10647760
- Publisher / Repository:
- American Physical Society
- Date Published:
- Journal Name:
- Physical Review Letters
- Volume:
- 135
- Issue:
- 19
- ISSN:
- 0031-9007
- Page Range / eLocation ID:
- 191003
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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