189 research outputs found

    Matter Enhanced Neutrino Oscillations with a Realistic Earth Density Profile

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    We have investigated matter enhanced neutrino oscillations with a mantle-core-mantle step function and a realistic Earth matter density profile in both a two and a three neutrino scenario. We found that the realistic Earth matter density profile can be well approximated with the mantle-core-mantle step function and that there could be an influence on the oscillation channel νμ→ντ\nu_\mu \to \nu_\tau due to resonant enhancement of one of the mixing angles.Comment: 8 pages, 5 figures (PostScript), MPLA LaTe

    Chizhov and Petcov Reply

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    We have found in [1] new conditions for a total neutrino conversion in the case of neutrino oscillations taking place in a medium, consisting of n = 2 (or 3) alternating layers with constant densities N1N_1 and N2N_2. It is claimed in [4] that our results are particular case of enhancement of neutrino oscillations, which was suggested earlier by other authors and was widely discussed in the literature. We refute these claims, confirming the novelty of our results.Comment: 2 pages, LATEX; concise (essentially 1 page) and somewhat modified version of Ref. SISSA 5/2000/EP (hep-ph/0003110); reply on the ``Comment on New Conditions for a Total Neutrino Conversion in a Medium'', Phys. Rev. Lett. 85 (2000) 3978; published as ``Chizhov and Petcov Reply'' in Phys. Rev. Lett. 85 (2000) 397

    Oscillations of high energy neutrinos in matter: Precise formalism and parametric resonance

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    We present a formalism for precise description of oscillation phenomena in matter at high energies or high densities, V > \Delta m^2/2E, where V is the matter-induced potential of neutrinos. The accuracy of the approximation is determined by the quantity \sin^2 2\theta_m \Delta V/2\pi V, where \theta_m is the mixing angle in matter and \Delta V is a typical change of the potential over the oscillation length (l \sim 2\pi/V). We derive simple and physically transparent formulas for the oscillation probabilities, which are valid for arbitrary matter density profiles. They can be applied to oscillations of high energy (E > 10 GeV) accelerator, atmospheric and cosmic neutrinos in the matter of the Earth, substantially simplifying numerical calculations and providing an insight into the physics of neutrino oscillations in matter. The effect of parametric enhancement of the oscillations of high energy neutrinos is considered. Future high statistics experiments can provide an unambiguous evidence for this effect.Comment: LaTeX, 5 pages, 1 figure. Linestyles in the figure corrected to match their description in the caption; improved discussion of the accuracy of the results; references added. Results and conclusions unchange

    Treatment of pain syndrome after aesthetic breast surgery with botulinum toxin type A

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    Objective. To justify the possibility of using botulotoxin type A for the prevention of pain syndrome after aesthetic endoprosthesis of the mammary glands.Material and Methods. The study included 72 women aged between 21 and 45 to whom were scheduled to perform breast endoprosthesis with silicone implants. All patients were divided into two groups: the first group included 38, the second group – 34 people. Two weeks before the expected date of surgery, botulotoxin type A in an amount of 100 U was injected into the patients of the first group to reduce pain syndrome in the pectoralis major muscle. Patients of the second (control) group were injected with a 0.9% NaCl solution (placebo effect) into the pectoralis major muscle. All patients underwent electroneuromyography (ENMG) to assess the denervation of the pectoralis major muscle before drug administration and two weeks after.Results. The intensity of pain syndrome was evaluated on the 1st-2nd day after surgery using a special questionnaire. In women of the first group, who were injected with botulinum toxin type A two weeks prior the intended surgery, a decrease in the intensity of the pain syndrome was observed, which in most cases allowed not to take analgesics at all. In women of the second group who were injected with a 0.9% NaCl solution, the severity of the pain syndrome reached its maximum values (according to the questionnaire), which required the prescription of analgesics, including narcotic ones, to reduce the severity of the pain syndrome. According to ENMG, when using botulotoxin type A by injecting into the pectoralis major muscle, denervation indices reached 55% compared to the initial ones, while using the saline solution, the ENMG indices did not change.Conclusion. Clinical use of botulotoxin type A injections into the pectoralis major muscle will improve the results of pain syndrome treatment after endoprosthetics of the mammary glands with implants in aesthetic surgery

    Stimulated Neutrino Transformation with Sinusoidal Density Profiles

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    Large amplitude oscillations between the states of a quantum system can be stimulated by sinusoidal external potentials with frequencies that are similar to the energy level splitting of the states or a fraction thereof. Situations when the applied frequency is equal to an integer fraction of the energy level splittings are known as parametric resonances. We investigate this effect for neutrinos both analytically and numerically for the case of arbitrary numbers of neutrino flavors. We look for environments where the effect may be observed and find that supernova are the one realistic possibility due to the necessity of both large densities and large amplitude fluctuations. The comparison of numerical and analytic results of neutrino propagation through a model supernova reveals it is possible to predict the locations and strengths of the stimulated transitions that occur.Comment: 14 pages, 6 figure

    The MSW effect and Matter Effects in Neutrino Oscillations

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    The MSW (Mikheyev-Smirnov-Wolfenstein) effect is the adiabatic or partially adiabatic neutrino flavor conversion in medium with varying density. The main notions related to the effect, its dynamics and physical picture are reviewed. The large mixing MSW effect is realized inside the Sun providing the solution of the solar neutrino problem. The small mixing MSW effect driven by the 1-3 mixing can be realized for the supernova (SN) neutrinos. Inside the collapsing stars new elements of the MSW dynamics may show up: the non-oscillatory transition, non-adiabatic conversion, time dependent adiabaticity violation induced by shock waves. Effects of the resonance enhancement and the parametric enhancement of oscillations can be realized for the atmospheric and accelerator neutrinos in the Earth. Precise results for neutrino oscillations in the low density medium with arbitrary density profile are presented and the attenuation effect is described. The area of applications is the solar and SN neutrinos inside the Earth, and the results are crucial for the neutrino oscillation tomography.Comment: 18 pages, latex, 6 figures, talk given at the Nobel Symposium 129, ``Neutrino Physics'', Haga Slott, August 19 - 24, 200

    Humoral immunity, vaccination period and demographic characteristics of first immunized smallpox vaccine recipients

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    General vaccination of population with vaccinia virus leaded to the eradication of smallpox, then it was finished because of the danger of adverse events. The recurrence of research interest in smallpox vaccine is due to the research of using the virus as a weapon of bioterrorism and the increased frequency of orthopoxvirus infections whereas the population immunity decline. The vaccinia virus is also used as a vector for creating recombinant vaccines. Understanding the pathway and predicting the immune response it will be able to avoid possible adverse events and excessive immunization. The aim of the study was to assess the correlations between humoral immunity, clinical signs during a vaccination period, sex and age characteristics of adults who had received several doses of vaccinia virus. We studied a vaccination clinical data of 135 subjects revaccinated with a smallpox vaccine from twice to 10 times. A total of 95% and 5% vaccine recipients experienced mild or moderate vaccination period, respectively. Inoculation skin lesions was noted at 127 subjects (94.1%). Among them more than 22% vaccine recipients experienced local or systemic adverse events. Compared to mild group moderate group had larger hyperemia (p = 0.04), scab (p = 0.01), healing time (p = 0.001). The age subjects with a moderate vaccination period is less than mild (p = 0.03), the chance of lymphadenopathy development is higher within moderate vaccination period (p < 0.001). Vaccinia neutralizing antibody titers were determined for 54 subjects using plaque reduction neutralization tests. There was a noted tendency of higher protective antibody values at women compared with men. Negative correlation between the antibody titers and the hyperemia size was revealed. Frequently axillary adenopathy is assotiated with higher protective antibody values. Vaccinia neutralizing antibody titers value are not associated with the presence and size of the lesion, the scab falling time, age and the number of previous vaccinations. The clinical variability and the immune response using the same vaccine and the same pattern vaccination would be explained by individual genetic differences that should be further explored

    Could One Find Petroleum Using Neutrino Oscillations in Matter?

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    In neutrino physics, it is now widely believed that neutrino oscillations are influenced by the presence of matter, modifying the energy spectrum produced by a neutrino beam traversing the Earth. Here, we will discuss the reverse problem, i.e. what could be learned about the Earth's interior from a single neutrino baseline energy spectrum, especially about the Earth's mantle. We will use a statistical analysis with a low-energy neutrino beam under very optimistic assumptions. At the end, we will note that it is hard to find petroleum with such a method, though it is not too far away from technical feasibility.Comment: 6 pages, 4 figures, EPL LaTeX. Final version to be published in Europhys. Let

    Atmospheric, long baseline, and reactor neutrino data constraints on θ13\theta_{13}

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    A new atmospheric neutrino oscillation tool which utilizes full three neutrino oscillation probabilities and a full three neutrino treatment of the MSW effect is combined with a standard analysis of the K2K, MINOS, and CHOOZ data to examine the bounds on θ13\theta_{13} implied by existing data, including the recent, more finely binned, Super-K atmospheric data. In the region L/Eν≳104L/E_\nu\gtrsim 10^4 km/GeV, we have previously found that the sub-dominant expansion does not converge and that terms linear in θ13\theta_{13} can be significant. The current analysis confirms this and leads to the conclusion that θ13\theta_{13} is bounded from above by the atmospheric data while CHOOZ provides the lower bound. We trace the origin of this result to fully contained data in the previously mentioned very long baseline region, to a combination of a quadratic in θ13\theta_{13} term in Pee{\mathcal P}_{ee} and a linear term in Peμ{\mathcal P}_{e\mu} and their contribution to ReR_e, a broad MSW resonance for the solar mass-squared difference at 180 MeV, and an increase in θ12\theta_{12} due to this resonant matter effect which alters the sign of the linear in θ13\theta_{13} term. Assuming CP is conserved in the lepton sector, we find θ13=−0.07−0.11+0.18\theta_{13}=-0.07^{+0.18}_{-0.11}, the asymmetry being a reflection of the importance of the linear in θ13\theta_{13} terms.Comment: 4 pages, 5 figures, typos corrected, manuscript shortene
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