Meteoric phenomena in the earth's atmosphere. Investigations of meteors, no. 2

Meteoritic radiance and ionization observations in earth atmospher

Lidar investigations of M-zone

The creation of pulse dye lasers tuned to resonant line of meteor produced admixtures of atmospheric constituents has made it possible to begin lidar investigations of the vertical distribution of mesospheric sodium concentration and its dynamics in the upper atmosphere. The observed morning increase of sodium concentration in the vertical column is probably caused by diurnal variations of sporadic meteors. The study of the dynamics of the sodium column concentration in the period of meteor streams activity confirms the suggestion of cosmic origin of these atoms. The short lived increase of sodium concentration brought about by a meteor stream, however, exceeds by one order the level of the sporadic background

Characteristics of air showers created by extremely high energy gamma-rays

The technique of adjoint cascade equations has been applied to calculate the properties of extremely high energy gamma-rays in the energy range 10^18--10^22 eV with taking into account the LPM effect and interactions of gamma-rays with the geomagnetic field. Such characteristics are analysed as the electron and muon contents at the observation level, the electron cascade curves, the lateral distribution functions of photoproduced muons.Comment: 36 pages, 19 figures, submitted to J.Phys.G: Nucl.Part.Phy

Design and construction of new central and forward muon counters for CDF II

New scintillation counters have been designed and constructed for the CDF upgrade in order to complete the muon coverage of the central CDF detector, and to extend this coverage to larger pseudorapidity. A novel light collection technique using wavelength shifting fibers, together with high quality polystyrene-based scintillator resulted in compact counters with good and stable light collection efficiency over lengths extending up to 320 cm. Their design and construction is described and results of their initial performance are reported.Comment: 20 pages, 15 figure

A study on the sharp knee and fine structures of cosmic ray spectra

The paper investigates the overall and detailed features of cosmic ray (CR) spectra in the knee region using the scenario of nuclei-photon interactions around the acceleration sources. Young supernova remnants can be the physical realities of such kind of CR acceleration sites. The results show that the model can well explain the following problems simultaneously with one set of source parameters: the knee of CR spectra and the sharpness of the knee, the detailed irregular structures of CR spectra, the so-called "component B" of Galactic CRs, and the electron/positron excesses reported by recent observations. The coherent explanation serves as evidence that at least a portion of CRs might be accelerated at the sources similar to young supernova remnants, and one set of source parameters indicates that this portion mainly comes from standard sources or from a single source.Comment: 13 pages, 4 figures, accepted for publication in SCIENCE CHINA Physics, Mechanics & Astronomy

Testing of the VENUS 4.12, DPMJET 2.55, QGSJET II-03 and SIBYLL 2.3 hadronic interaction models via help of the atmospheric vertical muon spectra

Uncertainties of the model energy spectra of the most energetic secondary π± -mesons (and K± -mesons) are discussed. Computer simulations of the partial energy spectra of the atmospheric vertical muons induced by primary cosmic particles with various fixed energies in interval 102 −107 GeV in terms of the VENUS 4.12, DPMJET 2.55, QGSJET II-03 and SIBYLL 2.3 models had been carried out with help of CORSIKA package. These partial spectra should be convoluted with the contemporary spectra of the primary cosmic particles. Results of simulations are compared with the contemporary atmospheric vertical muon flux data. Comparison shows that all models underestimate production of secondary π± -mesons (and K± -mesons) by factor of ∼ 2 at the most high energies. This underestimation induces more rapid development of extensive air showers in the atmosphere and results in uncertainties in estimates of energy and composition of the primary cosmic particles

Measuring extensive air showers with Cherenkov light detectors of the Yakutsk array: The energy spectrum of cosmic rays

The energy spectrum of cosmic rays in the range 10^15 eV to 6*10^19 eV has been studied using the air Cherenkov light detectors of the Yakutsk array. The total flux of photons produced by relativistic electrons (including positrons as well, hereafter) of extensive air showers in the atmosphere is used as the energy estimator of the primary particle initiating a shower. The resultant differential flux of cosmic rays exhibits, in accordance with previous measurements, a knee and ankle features at energies 3*10^15 and ~10^19 eV, respectively. A comparison of observational data with simulations is made in the knee and ankle regions in order to choose the models of galactic and extragalactic components of cosmic rays which describe better the energy spectrum measured.Comment: 27 pages, 22 figures, accepted for publication in New Journal of Physics (Focus Issue

Tunka Advanced Instrument for cosmic rays and Gamma Astronomy

The paper is a script of a lecture given at the ISAPP-Baikal summer school in 2018. The lecture gives an overview of the Tunka Advanced Instrument for cosmic rays and Gamma Astronomy (TAIGA) facility including historical introduction, description of existing and future setups, and outreach and open data activities.Comment: Lectures given at the ISAPP-Baikal Summer School 2018: Exploring the Universe through multiple messengers, 12-21 July 2018, Bol'shie Koty, Russi

Стволовой энцефалит Бикерстаффа, острый поперечный миелит и острая моторная аксональная нейропатия: сложности диагностики и лечения пациентов с перекрестными синдромами. Клиническое наблюдение

We report a 40-year-old woman presented with consciousness disturbance, ataxia, asymmetrical limb weakness, hyperreflexia. Due to magnetic resonance imaging findings, the patient was diagnosed with Bickerstaff’s brainstem encephalitis overlapped with acute transverse myelitis. Later she developed distal muscles atrophy and the electroneuromyographic study revealed axonal motor neuropathy, therefore acute motor axonal neuropathy was diagnosed. The patient underwent one course of intravenous immunoglobulin therapy with the regression of symptoms and magnetic resonance imaging changes. Nine months after symptoms onset, the patient has completely recovered. This overlapping case of Bickerstaff’s brainstem encephalitis, acute transverse myelitis and acute motor axonal neuropathy provides further support that these conditions are part of the same spectrum. Представлено клиническое наблюдение пациентки 40 лет с нарушением сознания, атаксией, асимметричным нижним парапа- резом, гиперрефлексией. В связи с обнаружением по данным магнитно-резонансной томографии изменений головного и спинного мозга был поставлен диагноз стволового энцефалита Бикерстаффа и острого поперечного миелита. Позднее ввиду развившейся атрофии дистальных мышц верхних и нижних конечностей было проведено электронейромиографическое исследование, выявившее изолированное поражение моторных волокон и подтвердившее присоединение острой моторной аксональной нейропатии. Однократный курс внутривенного иммуноглобулина дал положительный эффект c регрессом симптомов и очаговых изменений при повторном магнитно-резонансном исcледовании. Через 9 мес от дебюта болезни отмечено полное восстановление неврологического дефицита. Таким образом, был поставлен диагноз перекрестного синдрома стволового энцефалита Бикерстаффа, острого поперечного миелита и острой моторной аксональной нейропатии. Описанный случай может служить дополнительным подтверждением патогенетического сходства этих состояний.