Cosmoparticle physics: The universe as a laboratory of elementary particles

Khlopov, Maxim Yu.

doi:10.1134/s1063772915060141

Cited by 7 publications

(3 citation statements)

References 45 publications

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“…the coherent oscillation phase of the inflaton before reheating behaves as a MD era. For the probability of PBH formations in a MD era, we take into account the effects of anisotropies [66][67][68] and angular momentum [22], which suppress the PBH formation compared to the case without these effects [66,69]. Differences of this paper from [59] include the facts that we also consider the running of running parameter β s , that we take into account the effects of angular momentum on the PBH formation rate in the MD era, and that we do not rely on a spectator field.…”

Section: Introductionmentioning

confidence: 99%

Primordial black hole dark matter and LIGO/Virgo merger rate from inflation with running spectral indices: formation in the matter- and/or radiation-dominated universe

Kohri¹,

Terada²

2018

Class. Quantum Grav.

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We study possibilities to explain the whole dark matter abundance by primordial black holes (PBHs) or to explain the merger rate of binary black holes estimated from the gravitational wave detections by LIGO/Virgo. We assume that the PBHs are originated in a radiation-or matter-dominated era from large primordial curvature perturbation generated by inflation. We take a simple model-independent approach considering inflation with large running spectral indices which are parametrized by n s , α s , and β s consistent with the observational bounds. The merger rate is fitted by PBHs with masses of O(10) M produced in the radiation-dominated era. Then the running of running should be β s ∼ 0.025, which can be tested by future observation. On the other hand, the whole abundance of dark matter is consistent with PBHs with masses of asteroids (O(10 −17 ) M ) produced in an early matter-dominated era if a set of running parameters are properly realized. arXiv:1802.06785v4 [astro-ph.CO] 5 Nov 2018 which we are interested [41][42][43][44][45][46][47][48][49][50]. In earlier works including Refs. [37,[51][52][53][54][55][56][57][58][59][60][61][62][63][64][65], the BH merger rate for LIGO/Virgo events and/or the DM abundance in inflationary scenarios have been discussed.Here we do not explicitly introduce features like double inflation [58,62] or additional fields like a curvaton [59, 61, 63] to explain DM or LIGO/Virgo events. It is remarkable and encouraging that such a simple inflationary power spectrum can account for the LIGO/Virgo BH merger rate or the whole DM. The former (latter) is explained by the PBHs of intermediate masses M ∼ O(10)M (asteroid masses M ∼ O(10 −17 )M ). Another feature of this paper is that we consider both cases of BH formation in the radiation-dominated (RD) era and in an early matter-dominated (MD) era. The latter is less extensively studied in the literature, but it is wellmotivated in the inflationary cosmology since e.g. the coherent oscillation phase of the inflaton before reheating behaves as a MD era. For the probability of PBH formations in a MD era, we take into account the effects of anisotropies [66-68] and angular momentum [22], which suppress the PBH formation compared to the case without these effects [66,69]. Differences of this paper from Ref. [59] include the facts that we also consider the running of running parameter β s , that we take into account the effects of angular momentum on the PBH formation rate in the MD era, and that we do not rely on a spectator field.

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Section: Introductionmentioning

confidence: 99%

Primordial black hole dark matter and LIGO/Virgo merger rate from inflation with running spectral indices: formation in the matter- and/or radiation-dominated universe

Kohri¹,

Terada²

2018

Class. Quantum Grav.

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“…Astroparticle physics has been attracting attention for a long time (see, for example, articles [1][2][3][4]). At the same time, the processes of quantum electrodynamics (QED) in X-ray fields near pulsars and magnetars are intensively studied [5][6][7][8][9][10].…”

Section: Introductionmentioning

confidence: 99%

Emission of high-energy gamma quanta by ultrarelativistic electrons on nuclei in strong x-ray fields

Roshchupkin¹,

Dubov²,

Starodub³

2022

Preprint

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The possibility of radiation of high-energy gamma quanta with energies of the order of 100 GeV by ultrarelativistic electrons on nuclei in strong X-ray fields with intensities up to ∼ 10 27 Wcm −2 has been theoretically studied. It is shown that this effect can be realized under special experimental conditions in the process of resonant spontaneous bremsstrahlung radiation of ultrarelativistic electrons on nuclei in an external electromagnetic field. These special experimental conditions determine the characteristic energy of the electrons. This characteristic energy should be significantly less than the energy of the initial electrons. Under these conditions, spontaneous gamma quanta are emitted in a narrow cone with energies close to the energy of the initial electrons. Moreover, the resonant differential cross-sections of such processes can exceed the corresponding differential cross-section without an external field by twenty orders of magnitude. The results obtained can explain the occurrence of high-energy gamma quanta near pulsars and magnetars.

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“…Processes in strong electromagnetic fields are currently studied in applied and fundamental research papers . Sufficient attention is paid to processes in strong X-ray fields near neutron stars [22][23][24][25][26][27]. However, there is still no explanation for the anomalous flows of electron-positron pairs near these objects.…”

Section: Introductionmentioning

confidence: 99%

Resonant Production of an Ultrarelativistic Electron–Positron Pair at the Gamma Quantum Scattering by a Field of the X-ray Pulsar

2020

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The process of a resonant production of an ultrarelativistic electron–positron pair in the process of gamma-quantum scattering in the X-ray field of a pulsar is theoretically studied. This process has two reaction channels. Under resonant conditions, an intermediate electron (for a channel A) or a positron (for a channel B) enters the mass shell. As a result, the initial second-order process of the fine-structure constant in the X-ray field effectively splits into two first-order processes: the X-ray field-stimulated Breit–Wheeler process and the the X-ray field-stimulated Compton effect on an intermediate electron or a positron. The resonant kinematics of the process is studied in detail. It is shown that for the initial gamma quantum there is a threshold energy, which for the X-ray photon energy (1–102) keV has the order of magnitude (103–10) MeV. In this case, all the final particles (electron, positron, and final gamma quantum) fly in a narrow cone along the direction of the initial gamma quantum momentum. It is important to note that the energies of the electron–positron pair and the final gamma quantum depend significantly on their outgoing angles. The obtained resonant probability significantly exceeds the non-resonant one. The obtained results can be used to explain the spectrum of positrons near pulsars.

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Cosmoparticle physics: The universe as a laboratory of elementary particles

Abstract: The development of Zeldovich's ideas on the cosmological impact of particle theory is discussed in the context of cosmoparticle physics, studying fundamental relationship of macro-and micro-worlds.

Cited by 7 publications

References 45 publications

Primordial black hole dark matter and LIGO/Virgo merger rate from inflation with running spectral indices: formation in the matter- and/or radiation-dominated universe

Primordial black hole dark matter and LIGO/Virgo merger rate from inflation with running spectral indices: formation in the matter- and/or radiation-dominated universe

Emission of high-energy gamma quanta by ultrarelativistic electrons on nuclei in strong x-ray fields

Resonant Production of an Ultrarelativistic Electron–Positron Pair at the Gamma Quantum Scattering by a Field of the X-ray Pulsar

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