A lower bound on the mass of cold thermal dark matter from Planck

Bœhm, Céline; Dolan, Matthew J.; McCabe, Christopher

doi:10.1088/1475-7516/2013/08/041

Cited by 217 publications

(123 citation statements)

References 137 publications

(226 reference statements)

Supporting

Mentioning

119

Contrasting

Order By: Relevance

“…Figure 11 shows a plot of the m χ − ϵ parameter space of this model with several relevant constraints. Sufficiently light millicharged DM remains in thermal equilibrium with electrons and photons until after neutrinos decouple from the SM, altering the N eff measurement from the CMB power spectrum [51]. Since the irreducible annihilation to e þ e − heats the baryons, by requiring T m ðz ¼ 17.2Þ ≤ 4 K, 2 we can set an upper limit of ϵ ≲ 5 × 10 −5 , cutting the remaining parameter space down to a narrow window between m χ ∼10-100MeV and ϵ ∼ 5 × 10 −6 to 5 × 10 −5 .…”

Section: F Millicharged Dmmentioning

confidence: 99%

Implications of a 21-cm signal for dark matter annihilation and decay

2018

View full text Add to dashboard Cite

Measurements of the temperature of the baryons at the end of the cosmic dark ages can potentially set very precise constraints on energy injection from exotic sources, such as annihilation or decay of the dark matter. However, additional effects that lower the gas temperature can substantially weaken the expected constraints on exotic energy injection, whereas additional radiation backgrounds can conceal the effect of an increased gas temperature in measurements of the 21-cm hyperfine transition of neutral hydrogen. Motivated in part by recent claims of a detection of 21-cm absorption from z ∼ 17 by the EDGES experiment, we derive the constraints on dark matter annihilation and decay that can be placed in the presence of extra radiation backgrounds or effects that modify the gas temperature, such as DM-baryon scattering and early baryon-photon decoupling. We find that if the EDGES observation is confirmed, then constraints on light DM decaying or annihilating to electrons will in most scenarios be stronger than existing state-of-the-art limits from the cosmic microwave background, potentially by several orders of magnitude. More generally, our results allow mapping any future measurement of the global 21-cm signal into constraints on dark matter annihilation and decay, within the broad range of scenarios we consider.

show abstract

Section: F Millicharged Dmmentioning

confidence: 99%

Implications of a 21-cm signal for dark matter annihilation and decay

2018

View full text Add to dashboard Cite

show abstract

“…When ϕ becomes nonrelativistic and decays, its entropy is dumped either into some hidden sector bath (which would heat that bath relative to the SM bath) or into the SM bath, heating it further. If m ϕ ≳ 5 MeV when it decays to the SM (whether to electrons or neutrinos), there is little effect on BBN or cosmic microwave background (CMB) measurements of the number of relativistic degrees of freedom, N eff [11]; if, on the other hand, m ϕ ≲ 5 MeV and the decay is to neutrinos or to additional radiation in the dark sector, there may be observable signals in next-generation CMB experiments, depending on the decoupling temperature of the dark sector from the SM. In this paper we take an agnostic view towards the exact dynamics that determines the ratio of temperatures, but note that in many plausible scenarios,…”

Section: B Synthesis Temperaturementioning

confidence: 99%

Early Universe synthesis of asymmetric dark matter nuggets

2018

View full text Add to dashboard Cite

We compute the mass function of bound states of asymmetric dark matter-nuggets-synthesized in the early Universe. We apply our results for the nugget density and binding energy computed from a nuclear model to obtain analytic estimates of the typical nugget size exiting synthesis. We numerically solve the Boltzmann equation for synthesis including two-to-two fusion reactions, estimating the impact of bottlenecks on the mass function exiting synthesis. These results provide the basis for studying the late Universe cosmology of nuggets in a future companion paper.

show abstract

“…This dark acoustic oscillation (DAO) feature generically arises in any model where DM is coupled to relativistic particles until relatively late times. For instance, they occur if DM couples to neutrinos [41,[48][49][50][51][52][53][54] or photons [55][56][57][58], if DM interacts with a dark Uð1Þ D gauge boson [36,37,47,59,60], if DM couples to a light scalar field [61], or in the case of the so-called cannibal DM model [62][63][64]. We emphasize for the reader unfamiliar with the above body of work that if the DM sector couples purely gravitationally to the visible sector, some of these scenarios are surprisingly unconstrained.…”

Section: Introductionmentioning

confidence: 99%

Constraints on large-scale dark acoustic oscillations from cosmology

et al. 2014

View full text Add to dashboard Cite

If all or a fraction of the dark matter (DM) were coupled to a bath of dark radiation (DR) in the early Universe, we expect the combined DM-DR system to give rise to acoustic oscillations of the dark matter until it decouples from the DR. Much like the standard baryon acoustic oscillations, these dark acoustic oscillations (DAO) imprint a characteristic scale, the sound horizon of dark matter, on the matter power spectrum. We compute in detail how the microphysics of the DM-DR interaction affects the clustering of matter in the Universe and show that the DAO physics also gives rise to unique signatures in the temperature and polarization spectra of the cosmic microwave background (CMB). We use cosmological data from the CMB, baryon acoustic oscillations, and large-scale structure to constrain the possible fraction of interacting DM as well as the strength of its interaction with DR. Like nearly all knowledge we have gleaned about DM since inferring its existence this constraint rests on the betrayal by gravity of the location of otherwise invisible DM. Although our results can be straightforwardly applied to a broad class of models that couple dark matter particles to various light relativistic species, in order to make quantitative predictions, we model the interacting component as dark atoms coupled to a bath of dark photons. We find that linear cosmological data and CMB lensing put strong constraints on the existence of DAO features in the CMB and the large-scale structure of the Universe. Interestingly, we find that at most ∼5% of all DM can be very strongly interacting with DR. We show that our results are surprisingly constraining for the recently proposed double-disk DM model, a novel example of how large-scale precision cosmological data can be used to constrain galactic physics and subgalactic structure.

show abstract

A lower bound on the mass of cold thermal dark matter from Planck

Cited by 217 publications

References 137 publications

Implications of a 21-cm signal for dark matter annihilation and decay

Implications of a 21-cm signal for dark matter annihilation and decay

Early Universe synthesis of asymmetric dark matter nuggets

Constraints on large-scale dark acoustic oscillations from cosmology

Contact Info

Product

Resources

About