arXiv subjects

M. Yu. Khlopov

Publications and source records attributed to M. Yu. Khlopov.

At least 37 records · Page 2Linked to original sources

arXiv2019

No guaranteed neutrino astronomy without (enough) double bang tau and downward HESE muon tracks: An update version

IceCube Neutrino Astronomy is considered. The tau neutrino flavor paucity and the asymmetry for the tracks suggest a dominant atmospheric charm noise. The correlated cascades and tracks asymmetry with relevant statistics enforce the charm noise dominance in the data. The charm signal may explain at once the absence of correlation for the tracks data with the galactic plane and with known brightest gamma sources.

astro-ph.HE↗

arXiv2017

Search for Double Charged Particles as Direct Test for Dark Atom Constituents

The nonbaryonic dark matter of the Universe is assumed to consist of new stable particles. Stable particle candidates for cosmological dark matter are usually considered as neutral and weakly interacting. However stable charged leptons and quarks can also exist hidden in elusive dark atoms and can play a role of dark matter. Such possibility is strongly restricted by the constraints on anomalous isotopes of light elements that form positively charged heavy species with ordinary electrons. This problem might be avoided, if stable particles with charge -2 exist and there are no stable particles with charges +1 and -1. These conditions cannot be realized in supersymmetric models, but can be satisfied in several alternative scenarios, which are discussed in this paper. The excessive -2 charged particles are bound with primordial helium in O-helium atoms, maintaining specific nuclear-interacting form of the dark matter. O-helium dark matter can provide solution for the puzzles of dark matter searches. The successful development of composite dark matter scenarios appeals to experimental search for doubly charged constituents of dark atoms. Estimates of production cross section of such particles at LHC are presented and discussed. Signatures of double charged particles in the ATLAS experiment are outlined.

hep-ph↗

arXiv2017

Dark matter reflection of particle symmetry

In the context of the relationship between physics of cosmological dark matter and symmetry of elementary particles a wide list of dark matter candidates is possible. New symmetries provide stability of different new particles and their combination can lead to a multicomponent dark matter. The pattern of symmetry breaking involves phase transitions in very early Universe, extending the list of candidates by topological defects and even primordial nonlinear structures.

hep-ph↗

arXiv2017

Particle Dark Matter Candidates

A series of brief reviews collected in the present issue present various candidates for cosmological Dark Matter (DM) predicted by models of particle physics. The range from superlight axions to extended objects is covered. Though the possible list of candidates is far from complete it gives the flavor of the extensive field of Dark matter particle physics.

hep-ph↗

arXiv2016

Nonstandard cosmologies from physics beyond the Standard model

The modern cosmology is based on inflationary models with baryosynthesis and dark matter/energy.It implies extension of particle symmetry beyond the Standard model. Studies of physical basis of the modern cosmology combine direct searches for new physics at accelerators with its indirect non-accelerator probes, in which cosmological consequences of particle models play important role. The cosmological consequences of particle models inevitably go beyond the 'standard' cosmological $Λ$CDM model and some possible feature of such 'nonstandard'cosmological scenarios is the subject of the present brief review.

astro-ph.CO↗

arXiv2015

10 years of dark atoms of composite dark matter

In 2005 Sheldon Glashow has proposed his sinister model, opening the path to composite-dark-matter scenarios, in which heavy stable electrically charged particles bound in neutral atoms play the role of dark matter candidates. Though the general problem of new stable single charged particles, forming with ordinary electrons anomalous isotopes of hydrogen, turned out to be unresolvable in Glashow's scenario, this scenario stimulated development of composite dark matter models, which can avoid the trouble of anomalous isotope overproduction. In the simplest case composite dark matter may consist of -2 charged particles, bound by ordinary Coulomb interaction with primordial helium in OHe dark matter model. The advantage and open problems of this model are discussed.

hep-ph↗

arXiv2015

Dynamics of interacting quintessence

In this paper, we investigate coupled quintessence with scaling potential assuming specific forms of the coupling as $A$ namely, $α\dot{ρ_m}$, $β\dot{ρ_ϕ}$ and $σ(\dot{ρ_m}+\dot{ρ_ϕ})$, and present phase space analysis for three different interacting models. We focus on the attractor solutions that can give rise to late time acceleration with $Ω_{DE}/Ω_{DM}$ of order unity in order to alleviate the coincidence problem.

gr-qc↗

arXiv2014

Signatures of primordial black hole dark matter

The nonbaryonic dark matter of the Universe is assumed to consist of new stable forms of matter. Their stability reflects symmetry of micro world and mechanisms of its symmetry breaking. In the early Universe heavy metastable particles can dominate, leaving primordial black holes (PBHs) after their decay, as well as the structure of particle symmetry breaking gives rise to cosmological phase transitions, from which massive black holes and/or their clusters can originate. PBHs can be formed in such transitions within a narrow interval of masses about $10^{17}$g and, avoiding severe observational constraints on PBHs, can be a candidate for the dominant form of dark matter. PBHs in this range of mass can give solution of the problem of reionization in the Universe at the redshift $z\sim 5... 10$. Clusters of massive PBHs can serve as a nonlinear seeds for galaxy formation, while PBHs evaporating in such clusters can provide an interesting interpretation for the observations of point-like gamma-ray sources. Analysis of possible PBH signatures represents a universal probe for super-high energy physics in the early Universe in studies of indirect effects of the dark matter.

astro-ph.CO↗

arXiv2014

Probes for 4th generation constituents of dark atoms in Higgs boson studies at the LHC

The nonbaryonic dark matter of the Universe can consist of new stable charged species, bound in heavy neutral "atoms" by ordinary Coulomb interaction. Stable $\bar U$ (anti-$U$)quarks of 4th generation, bound in stable colorless ($\bar U \bar U \bar U $) clusters, are captured by the primordial helium, produced in Big Bang Nucleosynthesis, thus forming neutral "atoms" of O-helium (OHe), a specific nuclear interacting dark matter that can provide solution for the puzzles of direct dark matter searches. However, the existence of the 4th generation quarks and leptons should influence the production and decay rates of Higgs boson and is ruled out by the experimental results of the Higgs boson searches at the LHC, if the Higgs boson coupling to 4th generation fermions with is not suppressed. Here we argue that the difference between the three known quark-lepton families and the 4th family can naturally lead to suppression of this coupling, relating the accelerator test for such a composite dark matter scenario to the detailed study of the production and modes of decay of the 125.5 GeV boson, discovered at the LHC.

hep-ph↗

arXiv2014

Dark Atoms and Puzzles of Dark Matter Searches

The nonbaryonic dark matter of the Universe is assumed to consist of new stable forms of matter. Their stability reflects symmetry of micro world and particle candidates for cosmological dark matter are the lightest particles that bear new conserved quantum numbers. Dark matter candidates can appear in the new families of quarks and leptons and the existence of new stable charged leptons and quarks is possible, if they are hidden in elusive "dark atoms". Such possibility, strongly restricted by the constraints on anomalous isotopes of light elements, is not excluded in scenarios that predict stable double charged particles. The excessive -2 charged particles are bound in these scenarios with primordial helium in O-helium "atoms", maintaining specific nuclear-interacting form of the dark matter, which may provide an interesting solution for the puzzles of the direct dark matter searches.

hep-ph↗

arXiv2014

Primordial Black Hole Clusters and their Evolution

A possibility of pregalactic seeds of the Active Galactic Nuclei can be a nontrivial cosmological consequence of particle theory. Such seeds can appear as Primordial Black Hole (PBH) clusters, formed in the succession of phase transitions with spontaneous and then manifest breaking of the global U(1) symmetry. If the first phase transition takes place at the inflationary stage, a set of massive closed walls may be formed at the second phase transition and the collapse of these closed walls can result in formation of PBH clusters. We present the results of our studies of the evolution of such PBH Clusters.

astro-ph.CO↗

arXiv2012

Gamma-ray evidences of the dark matter clumps

We discuss the possibility of identification of point-like gamma-ray sources (PGS) with small scale dark matter (DM) clumps in our Galaxy. Gamma-rays are supposed to originate from annihilation of DM particles in the clumps, where annihilation rate is supposed to be enhanced, besides higher density, due to smaller relative velocities $v$ of DM particles. We parameterized the annihilation cross section $σ_\text{ann}(v)$ in the form of an arbitrary power law dependence on the relative velocity $v$ with/without factor of Sommerfeld-Gamow-Sakharov, implying existence of a new Coulomb-like interaction. Adopting different parameters of cross section and clump, satisfying condition $Ω\lesssim 0.2$ on density of DM particles of question, they are constrained from comparison with Fermi/LAT data on unidentified PGS as well as on diffuse $γ$-radiation; results are applied to concrete DM candidates. Such analysis is found to be sensitive enough to existing uncertainty in the density profiles of DM in the clump what can provide a tool for their test. Also we discuss possibilities when gamma-radiating clump changes visibly its position on celestial sphere and it is seen as a spatially extended gamma-source (EGS), what can be probed in future experiments like Gamma-400.

astro-ph.HE↗

arXiv2010

Proceedings to the 13th Workshop 'What Comes Beyond the Standard Models', Bled, July 12. - 22., 2010, Slovenia

1. Noncommutativity and Topology within Lattice Field Theories 2. The Construction of Quantum Field Operators 3. The Bargmann-Wigner Formalism for Spin 2 Fields 4. New Light on Dark Matter from the LHC 5. Extra Dimensional Metric Reversal Symmetry and its Prospect... 6. Masses and Mixing Matrices of Families within SU(3) Flavor Symmetry ... 7. Dark Atoms of the Universe: OHe Nuclear Physics, 8. Can the Matter-Antimatter Asymmetry be Easier to Understand Within the "Spin-charge-family-theory", .. 9. Mass Matrices of Twice Four Families of Quarks and Leptons, ...in the "Spin-charge-family-theory" 10. Bohmian Quantum Mechanics or What Comes Before the Standard Model 11. Backward Causation in Complex Action Model ... 12. Is the Prediction of the "Spin-charge-family-theory" in Disagreement with the XENON100..? 13. Masses and Mixing Matrices of Families of Quarks and Leptons Within the "Spin-charge-family-theory" 14. Can the Stable Fifth Family of the "Spin-charge-family-theory" ...Form the Fifth Antibaryon Clusters with Ordinary He Nucleus? 15. Puzzles of Dark Matter - More Light on Dark Atoms? 16. Families of Spinors in d = (1 + 5)...and Masslessness 17. Are Superheavy Quark Clusters Candidates for the Dark Matter? 18. Complex Action Functioning as Cutoff and De Broglie-Bohm Particle 19. Where does the Science Go? 20. VIA Presentation

hep-ph↗

arXiv2009

Proceedings to the 12th Workshop 'What Comes Beyond the Standard Models', Bled, July 14. - 24., 2009, Slovenia

Contents: 1. Likelihood Analysis of the Next-to-minimal Supergravity Motivated Model (C. Balazs and D. Carter) 2. The Multiple Point Principle: Characterization of the Possible Phases for the SMG (D.L. Bennett) 3. Does Dark Matter Consist of Baryons of New Stable Family Quarks? (G. Bregar and N.S. Mankoc Borstnik) 4. P, C and T for Truly Neutral Particles (V.V. Dvoeglazov) 5. Relativistic Equations for Spin Particles: What Can We Learn From Noncommutativity? (V.V. Dvoeglazov) 6. Radiative Charged Fermion Masses and Quark Mixing (VCKM)4x4 in a SU(3) Gauged Flavor Symmetry Model (A. Hernandez-Galeana) 7. Low Energy Binding of Composite Dark Matter with Nuclei as a Solution for the Puzzles of Dark Matter Searches (M.Yu. Khlopov, A.G. Mayorov and E.Yu. Soldatov) 8. On the Possibilities and Impossibilities of Random Dynamics (A. Kleppe) 9. Spin Connection Makes Massless Spinor Chirally Coupled to Kaluza-Klein Gauge Field After Compactification of $M^{1+5}$ to $M^{1+3}$ x Infinite Disc Curved on $S^2$ (D. Lukman, N.S. Mankoc Borstnik and H.B. Nielsen) 10. Offering the Mechanism for Generating Families - the Approach Unifying Spins and Charges Predicts New Families (N.S. Mankoc Borstnik) 11. Confusions That are so Unnecessary (R. Mirman) 12. - 17. Discussion Sections 18. Presentation of VIA and Bled 2009 Workshop Videoconferences (M.Yu. Khlopov)

hep-ph↗

arXiv2008

Proceedings to the 11th Workshop 'What Comes Beyond the Standard Models', Bled, July 15 - 25, 2008, Slovenia

Contents: 1. Does the Dark Matter Consist of Baryons of New Heavy Stable Family Predicted by the Approach Unifying Spins and Charges? (G. Bregar and N.S. Mankoc Borstnik) 2. Lorentz Transformations for a Photon (V.V. Dvoeglazov) 3. Is the Space-Time Non-commutativity Simply Non-commutativity of Derivatives? (V.V. Dvoeglazov) 4. Composite Dark Matter: Solving the Puzzles of Underground Experiments? (M.Yu. Khlopov, A.G. Mayorov and E.Yu. Soldatov) 5. Spin Connection Makes Massless Spinor Chirally Coupled to Kaluza-Klein Gauge Field After Compactification of $M^{1+5}$ to $M^{1+3}$ x Infinite Disc Curved on $S^2$ (D. Lukman, N.S. Mankoc Borstnik and H.B. Nielsen) 6. Some Obvious Matters of Physics That Are Not Obvious (R. Mirman) 7. Discussions on the Puzzles of the Dark Matter Search (Video Conference Participants) 8. Scattering With Very Heavy Fermions (A. Kleppe) 9. Scientific-Educational Complex -- Virtual Institute of Astroparticle Physics (M.Yu. Khlopov)

hep-ph↗

arXiv2008

How to Measure the Cosmic Curvature

The conventional method to determine the cosmic curvature is to measure the total mass density $Ω_{\rm tot}$. Unfortunately the observational $Ω_{\rm tot}$ is closely near the critical value 1. The computation of this paper shows that $Ω_{\rm tot}\approx 1$ is an inevitable result for the young universe independent of the spatial topology. So the mass density is not a good criterion to determine the cosmic curvature. In this paper, we derive a new criterion based on the galactic distribution with respect to redshift $z$, which only depends on the cosmological principle and geometry. The different type of spatial topology will give different results, then the case can be definitely determined.

gr-qc↗

arXiv2008

Project of Virtual Institute of Astroparticle Physics

Studies in astroparticle physics are actively developed all over the world. It is clear that the effectiveness of the work depends strongly on the information exchange rate and on the overall coordination of this activity. An international forum, be it virtual, which can join all the groups and coordinate their efforts would give a boost to this cooperation. Particularly this is important for isolated scientific groups and scientists from small countries which can contribute a lot to this work being a part of the large international collaboration. Objectives, instruments and structure of proposed Virtual Instutute of Astroparticle Physics are discussed.

astro-ph↗

arXiv2007

Primordial heavy elements in composite dark matter models

A widely accepted viewpoint is to consider candidates for cosmological dark matter as neutral and weakly interacting particles, as well as to consider only light elements in the pregalactic chemical composition. It is shown that stable charged leptons and quarks can exist and, hidden in elusive atoms, play the role of dark matter. The inevitable consequence of realistic scenarios with such composite atom-like dark matter is existence of significant or even dominant fraction of "atoms", binding heavy -2 charged particles and He-4 nuclei. Being alpha-particles with shielded electric charge, such atoms catalyse a new path of nuclear transformations in the period of Big Bang Nucleosynthesis, which result in primordial heavy elements. The arguments are given, why such scenario escapes immediate contradiction with observations and challenges search for heavy stable charged particles in cosmic rays and at accelerators.

astro-ph↗