Publications by Oleg Ruchayskiy

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ORIGIN is a proposal for the M3 mission call of ESA aimed at the study of metal creation from the epoch of cosmic dawn. Using high-spectral resolution in the soft X-ray band, ORIGIN will be able to identify the physical conditions of all abundant elements ...

In thermal equilibrium the ground state of the plasma of Standard Model particles is determined by temperature and exactly conserved combinations of baryon and lepton numbers. We show that at nonzero values of the global charges a translation invariant and ...

We present a comprehensive review of keV-scale sterile neutrino Dark Matter, collecting views and insights from all disciplines involved - cosmology, astrophysics, nuclear, and particle physics - in each case viewed from both theoretical and experimental/o ...

A signal from decaying dark matter (DM) can be unambiguously distinguished from spectral features of astrophysical or instrumental origin by studying its spatial distribution. We demonstrate this approach by examining the recent claim of Loewenstein and Ku ...

We present results of a search for the 3.5 keV emission line in our recent very long (similar to 1.4 Ms) XMM-Newton observation of the Draco dwarf spheroidal galaxy. The astrophysical X-ray emission from such dark matter-dominated galaxies is faint, thus t ...

The sterile neutrino is a viable darkmatter candidate that can be produced in the early Universe via non-equilibrium processes, and would therefore possess a highly non-thermal spectrum of primordial velocities. In this paper we analyse the process of stru ...

High-resolution N-body simulations of galactic cold dark matter haloes indicate that we should expect to find a few satellite galaxies around the Milky Way whose haloes have a maximum circular velocity in excess of 40 km s-1. Yet, with the exception of the ...

The diversity of structures in the Universe (from the smallest galaxies to the largest superclusters) has formed under the pull of gravity from the tiny primordial perturbations that we see imprinted in the cosmic microwave background. A quantitative descr ...

Many extensions of the Standard Model (SM) predict new neutral vector bosons at energies accessible by the Large Hadron Collider (LHC). We study an extension of the SM with new chiral fermions subject to non-trivial anomaly cancellations. If the new fermio ...

We suggest a new efficient way to constrain a certain class of large scale modifications of gravity. We show that the scale-free relation between density and size of dark matter halos, predicted within the ACDM model with Newtonian gravity, gets modified i ...

We show that the evolution of magnetic fields in a primordial plasma, filled with standard model particles at temperatures T greater than or similar to 10 MeV, is strongly affected by the chiral anomaly-an effect previously neglected. Although reactions, e ...

How structures of various scales formed and evolved from the early Universe up to present time is a fundamental question of astrophysical cosmology. EDGE (Piro et al., 2007) will trace the cosmic history of the baryons from the early generations of massive ...

We derive constraints on the parameters of the radiatively decaying dark matter (DM) particle, using the XMM-Newton EPIC spectra of the Andromeda galaxy (M31). Using the observations of the outer (5-13 arcmin) parts of M31, we improve the existing constrai ...

Heavy Neutral Leptons (HNLs) are hypothetical particles predicted by many extensions of the Standard Model. These particles can, among other things, explain the origin of neutrino masses, generate the observed matter-antimatter asymmetry in the Universe an ...

We revisit Lyman-alpha bounds on the dark matter mass in Lambda Warm Dark Matter (Lambda-WDM) models, and derive new bounds in the case of mixed Cold plus Warm models (Lambda-CWDM), using a set up which is a good approximation for several theoretically wel ...

In the recent paper of Hooper and Goodenough (2010) [10] it was reported that gamma-ray emission from the Galactic Center region contains an excess compared to the contributions from the large-scale diffuse emission and known point sources. This excess was ...

In theories with chiral couplings, one of the important consistency requirements is that of the cancellation of a gauge anomaly. In particular, this is one of the conditions imposed on the hypercharges in the standard model. However, anomaly cancellation c ...

We consider a modification of electrodynamics by an additional light massive vector field, interacting with the photon via Chern-Simons-like coupling. This theory predicts observable effects for the experiments studying the propagation of light in an exter ...

We report a weak line at 3.52 +/- 0.02 keV in x-ray spectra of the Andromeda galaxy and the Perseus galaxy cluster observed by the metal-oxide-silicon (MOS) and p-n (PN) CCD cameras of the XMM-Newton telescope. This line is not known as an atomic line in t ...

In an extension of the Standard Model by three relatively light right-handed neutrinos (the νMSM model) the role of the dark matter particle is played by the lightest sterile neutrino. We demonstrate that the observations of the extragalactic x-ray backgro ...

Oleg Ruchayskiy

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ORIGIN: metal creation and evolution from the cosmic dawn

Long-Range Magnetic Fields in the Ground State of the Standard Model Plasma

A White Paper on keV sterile neutrino Dark Matter

Searching for dark matter in X-rays: how to check the dark matter origin of a spectral feature

Searching for decaying dark matter in deep XMM-Newton observation of the Draco dwarf spheroidal

Satellite galaxies in semi-analytic models of galaxy formation with sterile neutrino dark matter

The haloes of bright satellite galaxies in a warm dark matter universe

A new framework for numerical simulations of structure formation

Anomaly driven signatures of new invisible physics at the Large Hadron Collider

Proposed new probe of modified gravity

Self-Consistent Evolution of Magnetic Fields and Chiral Asymmetry in the Early Universe

EDGE: Explorer of diffuse emission and gamma-ray burst explosions

Constraints on decaying dark matter from XMM-Newton observations of M31

Sensitivity of the SHiP experiment to Heavy Neutral Leptons

Lyman-alpha constraints on warm and on warm-plus-cold dark matter models

A comment on the emission from the Galactic Center as seen by the Fermi telescope

Observational manifestations of anomaly inflow

Anomaly induced effects in a magnetic field

Unidentified Line in X-Ray Spectra of the Andromeda Galaxy and Perseus Galaxy Cluster

The masses of active neutrinos in the nuMSM from X-ray astronomy