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}.
The Cos- mic Microwave Background spectrum from the full COBE FIRAS data set
5 Pith papers cite this work. Polarity classification is still indexing.
abstract
We have refined the analysis of the data from the FIRAS (Far InfraRed Absolute Spectrophotometer) on board the COBE (COsmic Background Explorer). The FIRAS measures the difference between the cosmic microwave background and a precise blackbody spectrum. We find new tighter upper limits on general deviations from a blackbody spectrum. The RMS deviations are less than 50 parts per million of the peak of the CMBR. For the Comptonization and chemical potential we find $|y| < 15\times10^{-6}$ and $|\mu| < 9\times10^{-5}$ (95\% CL). There are also refinements in the absolute temperature, 2.728 $\pm$ 0.004 K (95\% CL), and dipole direction, $(\ell,b)=(264.14^\circ\pm0.30, 48.26^\circ\pm0.30)$ (95\% CL), and amplitude, $3.372 \pm 0.007$ mK (95\% CL). All of these results agree with our previous publications.
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2026 5roles
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Tensor perturbations from first-order phase transitions and domain wall annihilation induce curvature fluctuations at second order that form primordial black holes, allowing asteroid-mass PBHs to comprise all dark matter for specific parameter ranges with associated gravitational wave peaks in LISA,
tSZ cross-correlations with large-scale structure tracers prefer low S8 and strong baryonic feedback, yielding S8 = 0.72 and low group baryon fraction in FLAMINGO simulations.
Thermal spectra can be produced by certain classes of emission kernels without probe thermalization, as when the differential cross section depends on angle but not on the Mandelstam variable s, providing a kernel-based criterion to distinguish genuine equilibrium from kernel artifacts.
Fermi LAT data on mini-spikes around stellar-mass black holes rules out substantial regions of Inert Doublet Model dark matter parameter space, especially at multi-TeV masses.
citing papers explorer
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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}.
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Primordial Black Hole from Tensor-induced Density Fluctuation: First-order Phase Transitions and Domain Walls
Tensor perturbations from first-order phase transitions and domain wall annihilation induce curvature fluctuations at second order that form primordial black holes, allowing asteroid-mass PBHs to comprise all dark matter for specific parameter ranges with associated gravitational wave peaks in LISA,
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FLAMINGO: The thermal history of the Universe from tSZ effect cross-correlations and its dependencies on cosmology and baryon physics
tSZ cross-correlations with large-scale structure tracers prefer low S8 and strong baryonic feedback, yielding S8 = 0.72 and low group baryon fraction in FLAMINGO simulations.
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Thermal Spectra Without Detailed Balance
Thermal spectra can be produced by certain classes of emission kernels without probe thermalization, as when the differential cross section depends on angle but not on the Mandelstam variable s, providing a kernel-based criterion to distinguish genuine equilibrium from kernel artifacts.
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Probing the Inert Doublet Dark Matter with Stellar-Mass Black Hole Mini-Spikes
Fermi LAT data on mini-spikes around stellar-mass black holes rules out substantial regions of Inert Doublet Model dark matter parameter space, especially at multi-TeV masses.