Non-equilibrium relativistic SIDM halo collapse produces seed black holes of mass ~3e-8 of the halo mass at apparent horizon formation.
Revisiting constraints on small scale perturbations from big-bang nucleosynthesis
2 Pith papers cite this work. Polarity classification is still indexing.
abstract
We revisit the constraints on the small scale density perturbations ($10^4\,\mathrm{Mpc}^{-1}\lesssim k \lesssim10^5\,\mathrm{Mpc}^{-1}$) from the modification of the freeze-out value of the neutron-proton ratio at big-bang nucleosynthesis era. Around the freeze-out temperature $T\sim 0.5\,\mathrm{MeV}$, the universe can be divided into several local patches which have different temperatures since any perturbation which enters the horizon after the neutrino decoupling has not diffused yet. Taking account of this situation, we calculate the freeze-out value in detail. We find that the small scale perturbations decrease the n-p ratio in contrast to previous works. With use of the latest observed $^4$He abundance, we obtain the constraint on the power spectrum of the curvature perturbations as $\Delta^2_\mathcal{R}\lesssim 0.018$ on $10^4\,\mathrm{Mpc}^{-1}\lesssim k \lesssim 10^5\,\mathrm{Mpc}^{-1}$.
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Dissipation of small-scale primordial perturbations after neutrino decoupling cools relic neutrinos and reduces their abundance, enabling PTOLEMY to constrain the primordial curvature power spectrum to O(0.1) on scales k ≲ 3×10^5 Mpc^{-1}.
citing papers explorer
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Non-Equilibrium Relativistic Core Collapse of Self-Interacting Dark Matter Halos -- Limits On Seed Black Hole Mass
Non-equilibrium relativistic SIDM halo collapse produces seed black holes of mass ~3e-8 of the halo mass at apparent horizon formation.
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Probing the small-scale primordial power spectrum via relic neutrinos and acoustic reheating
Dissipation of small-scale primordial perturbations after neutrino decoupling cools relic neutrinos and reduces their abundance, enabling PTOLEMY to constrain the primordial curvature power spectrum to O(0.1) on scales k ≲ 3×10^5 Mpc^{-1}.