Resonant production of the sterile neutrino dark matter and fine-tunings in the [nu]MSM

The generation of lepton asymmetry below the electroweak scale has a considerable impact on production of dark matter sterile neutrinos. Oscillations or decays of the heavier sterile neutrinos in the neutrino minimal standard model can give rise to the requisite lepton asymmetry, provided the masses of the heavier neutrinos are sufficiently degenerate. We study the renormalization group evolution of the mass difference of these singlet fermions to understand the degree of necessary fine-tuning. We construct an example of the model that can lead to a technically natural realization of this low-energy degeneracy.Comment: 8 pages, 5 figure

Standard Model Higgs boson mass from inflation

We analyse one-loop radiative corrections to the inflationary potential in the theory, where inflation is driven by the Standard Model Higgs field. We show that inflation is possible provided the Higgs mass m_H lies in the interval m_min<m_H<m_max, where m_min=[136.7+(m_t-171.2)*1.95]GeV, m_max=[184.5+(m_t-171.2)*0.5]GeV and m_t is the mass of the top quark. Moreover, the predictions of the spectral index of scalar fluctuations and of the tensor-to-scalar ratio practically do not depend on the Higgs mass within the admitted region and are equal to n_s=0.97 and r=0.0034 correspondingly.Comment: 5 pages, 3 figures. Journal version+misprint fixed and added reference to the two-loop analysis paper for convenienc

Diagnostic Value Parameters Of Acute Phase Reactances Of Infectious-inflammatory Process In Diagnostics Of Early Neonatal Sepsis

An advanced progress of clinical neonatology in recent years has enabled to achieve considerable success in newborn management with due respect to both medical treatment and general care, especially in the group of neonates with low body weight at birth. At the same time, neonatal sepsis in the early period still predetermine sickness and mortality of newborns.Material and methods. Clinical-paraclinical indices with detection of diagnostic value of C-reactive protein and interleukins-6 and 8 were evaluated in 100 neonates with available susceptibility factors to early neonatal infection from mother\u27s side and clinical signs of organ dysfunction in neonates with precautions of generalized infectious-inflammatory process at the end of their first day of life.Results. The data obtained substantiate that low concentrations of IL-6 and IL-8 prevail, and therefore the mentioned mediators hardly can be used to verify early neonatal infection. In the majority of children C-reactive protein elevated the concentration of 10.0 mg/L which is traditionally considered to be a discriminant as to the verification of an infectious process in newborns.Conclusions. None of the clinical signs associated with infectious-inflammatory process in newborns in the first two days of their life enabled to verify reliably availability of systemic bacterial infection

O(4) symmetric singular solutions and multiparticle cross sections in ϕ4\phi^4 theory at tree level

We solve the classical euclidean boundary value problem for tree-level multiparticle production in $\phi^4$ theory at arbitrary energies in the case of $O(4)$ symmetric field configurations. We reproduce known low-energy results and obtain a lower bound on the tree cross sections at arbitrary energies.Comment: LaTeX, 9pp + 2 Postscript figures, tar-compressed and uuencoded using uufiles; minor Postscript bug fixe

Gauge singlet scalar as inflaton and thermal relic dark matter

We show that, by adding a gauge singlet scalar S to the standard model which is nonminimally coupled to gravity, S can act both as the inflaton and as thermal relic dark matter. We obtain the allowed region of the (m_s, m_h) parameter space which gives a spectral index in agreement with observational bounds and also produces the observed dark matter density while not violating vacuum stability or nonperturbativity constraints. We show that, in contrast to the case of Higgs inflation, once quantum corrections are included the spectral index is significantly larger than the classical value (n = 0.966 for N = 60) for all allowed values of the Higgs mass m_h. The range of Higgs mass compatible with the constraints is 145 GeV < m_h < 170 GeV. The S mass lies in the range 45 GeV < ms < 1 TeV for the case of a real S scalar with large quartic self-coupling lambdas, with a smaller upper bound for smaller lambdas. A region of the parameter space is accessible to direct searches at the LHC via h-->SS, while future direct dark matter searches should be able to significantly constrain the model.Comment: 13 pages, 7 figures. Published versio

Compact extra-dimensions as solution to the strong CP problem

We show that the strong CP problem can, in principle, be solved dynamically by adding extra-dimensions with compact topology. To this aim we consider a toy model for QCD, which contains a vacuum angle and a strong CP like problem. We further consider a higher dimensional theory, which has a trivial vacuum structure and which reproduces the perturbative properties of the toy model in the low-energy limit. In the weak coupling regime, where our computations are valid, we show that the vacuum structure of the low-energy action is still trivial and the strong CP problem is solved. No axion-like particle occur in this setup and therefore it is not ruled out by astrophysical bounds.Comment: Discussion adde