Constraints on ultracompact minihalos from the extragalactic gamma-ray background observation

Zhang, Xing-Fu; Cheng, Ji-Gui; Zhu, Ben-Yang; Liu, Tian-Ci; Liang, Yun-Feng; Liang, En‐Wei

doi:10.1103/physrevd.105.043011

Cited by 6 publications

(8 citation statements)

References 73 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Note that the limits are independent on the PBH mass, and similar features can be also found in previous works [26,30,35,61,62]. In fact, since the annihilation rate of the DM particle within UCMH is proportional to the PBH mass Γ anni ∝ M PBH , the energy injection rate per unit volume is…”

Section: The Basic Properties Of Ucmhs and Upper Limits On The Abunda...supporting

confidence: 83%

“…In the mixed dark matter scenarios investigated here the observations of γ-ray and CMB can be also used to constrain the abundance of PBHs. For example, the high energy photons produced by the DM annihilation within UCMHs can contribute to the extragalactic γ-ray background (EGB) [26,30,34,35,58,61,[68][69][70][71][72]. Using the observations of EGB by, e.g., the Fermi telescope, the upper limits on the abundance of PBHs can be obtained [34,35,61].…”

Section: The Basic Properties Of Ucmhs and Upper Limits On The Abunda...mentioning

confidence: 99%

“…For example, the high energy photons produced by the DM annihilation within UCMHs can contribute to the extragalactic γ-ray background (EGB) [26,30,34,35,58,61,[68][69][70][71][72]. Using the observations of EGB by, e.g., the Fermi telescope, the upper limits on the abundance of PBHs can be obtained [34,35,61]. The authors of [35] used the updated Fermi-LAT EGB measurement to derive the upper limits on the abundance of PBHs.…”

Section: The Basic Properties Of Ucmhs and Upper Limits On The Abunda...mentioning

confidence: 99%

“…Using the observations of EGB by, e.g., the Fermi telescope, the upper limits on the abundance of PBHs can be obtained [34,35,61]. The authors of [35] used the updated Fermi-LAT EGB measurement to derive the upper limits on the abundance of PBHs. They found that for the b b annihilation channel the upper limit is f UCMH ∼ 6×10 −5 for m χ = 10 GeV with σv = 3 × 10 −26 cm 3 s −1 (shown in Fig.…”

Section: The Basic Properties Of Ucmhs and Upper Limits On The Abunda...mentioning

confidence: 99%

“…It is expected that the annihilation rate of DM particles within UCMHs is very large, because it is proportional to the square number density. The influences of DM annihilation within UCMHs on the astronomical observations have been investigated by previous works, while those studies have focused on the epoch after recombination z < ∼ z rec 1100 [26][27][28][29][30][31][32][33][34][35][36][37][38][39][40]. On the other hand, since UCMHs can be formed before cosmological recombination, DM annihilation within UCMHs should have influences on the early universe.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Constraints on primordial black holes with CMB spectral distortions

Yang

2022

Phys. Rev. D

View full text Add to dashboard Cite

In the mixed dark matter scenarios consisting of primordial black holes (PBHs) and weakly interacting massive particles (WIMPs), WIMPs can be accreted onto PBHs to form ultracompact minihalos (UCMHs) with a density spike in the early universe. Compared with the classical dark matter halo, UCMHs are formed earlier and have a higher density of center. Since the annihilation rate is proportional to the squared number density of WIMPs, it is expected that WIMPs annihilation within UCMHs is enhanced and has influences on the early universe. Between the time of recombination and matter-radiation equality, the energy released from WIMPs annihilation within UCMHs is injected into the Universe resulting in CMB y-type distortion. We investigate these effects and derive the upper limits on the abundance of PBHs taking advantage of the observational results of Far Infrared Absolute Spectrophotometer (FIRAS). We find that for the WIMPs mass range 1 ≤ mχ ≤ 1000 GeV, the upper limits on the abundance of PBHs are 5 × 10 −3 ≤ ΩPBH ≤ 5 × 10 −2 .

show abstract

Section: The Basic Properties Of Ucmhs and Upper Limits On The Abunda...supporting

confidence: 83%

Section: The Basic Properties Of Ucmhs and Upper Limits On The Abunda...mentioning

confidence: 99%

Section: The Basic Properties Of Ucmhs and Upper Limits On The Abunda...mentioning

confidence: 99%

Section: The Basic Properties Of Ucmhs and Upper Limits On The Abunda...mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Constraints on primordial black holes with CMB spectral distortions

Yang

2022

Phys. Rev. D

View full text Add to dashboard Cite

show abstract

Minihalos as probes of the inflationary spectrum: accurate boost factor calculation and new CMB constraints

Abellán

Facchinetti

2023

J. Cosmol. Astropart. Phys.

View full text Add to dashboard Cite

Although the spectrum of primordial fluctuations has been accurately measured on scales above ∼ 0.1 Mpc, only upper limits exist on smaller scales. In this study, we investigate generic monochromatic enhancements to the ΛCDM spectrum that trigger the collapse of ultracompact minihalos (UCMHs) well before standard structure formation. We refine previous treatments by considering a mixed population of halos with different density profiles, that should realistically arise as a consequence of late-time accretion and mergers. Assuming that dark matter (DM) can self-annihilate, we find, as expected, that UCMHs can greatly enhance the annihilation rate around recombination, significantly imprinting the cosmic microwave background (CMB) anisotropies. However, we provide additional insight on the theoretical uncertainties that currently impact that boost and which may affect late-time probes such as the 21 cm line or γ-ray signals. We derive constraints on the primordial power spectrum on small scales using the ExoCLASS/HYREC codes and the Planck legacy data. We account for the velocity dependence of the DM annihilation cross-section (s- or p-wave), annihilation channel, the DM particle mass and the inclusion of late-time halo mergers. Our s-wave constraints are competitive with previous literature, excluding primordial amplitudes 𝒜*≳ 10-6.5 at wavenumbers k ∼ 104 - 107 Mpc-1. For the first time, we highlight that even p-wave processes have constraining power on the primordial spectrum for cross-sections still allowed by currently the strongest astrophysical constraints. Finally, we provide an up-to-date compilation of the most stringent limits on the primordial power spectrum across a wide range of scales.

show abstract

Impact of radiation from primordial black holes on the 21-cm angular-power spectrum in the dark ages

Yang

2022

Phys. Rev. D

View full text Add to dashboard Cite

Constraints on ultracompact minihalos from the extragalactic gamma-ray background observation

Cited by 6 publications

References 73 publications

Constraints on primordial black holes with CMB spectral distortions

Constraints on primordial black holes with CMB spectral distortions

Minihalos as probes of the inflationary spectrum: accurate boost factor calculation and new CMB constraints

Impact of radiation from primordial black holes on the 21-cm angular-power spectrum in the dark ages

Contact Info

Product

Resources

About