15 research outputs found

    2D Spectroscopy of Candidate Polar-Ring Galaxies: I. The Pair of Galaxies UGC 5600/09

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    Observations of the pair of galaxies VV 330 with the SCORPIO multimode instrument on the 6-m Special Astrophysical Observatory telescope are presented. Large-scale velocity fields of the ionized gas in H-alfa and brightness distributions in continuum and H-alfa have been constructed for both galaxies with the help of a scanning Fabry Perot interferometer. Long-slit spectroscopy is used to study the stellar kinematics. Analysis of the data obtained has revealed a complex structure in each of the pair components. Three kinematic subsystems have been identified in UGC 5600: a stellar disk, an inner gas ring turned with respect to the disk through ~80degrees, and an outer gas disk. The stellar and outer gas disks are noncoplanar. Possible scenarios for the formation of the observed multicomponent kinematic galactic structure are considered, including the case where the large-scale velocity field of the gas is represented by the kinematic model of a disk with a warp. The velocity field in the second galaxy of the pair, UGC 5609, is more regular. A joint analysis of the data on the photometric structure and the velocity field has shown that this is probably a late-type spiral galaxy whose shape is distorted by the gravitational interaction, possibly, with UGC 5600.Comment: 18 pages, 6 figure

    New materials based on tubular nanodimensional structures 1. Synthesis, structural studies and determination of interproton distances in solutions of functionalized thiacalix[4]arenes according to NMR spectroscopic data (NOESY)

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    New derivatives of p-tert-butylthiacalix[4]arene were synthesized. The conformation of the macrocycles and interproton distances in the synthesized thiacalix[4]arenes in solutions were determined by NMR spectroscopy. p-tert-Butylthiacalix[4]arene distally disubstituted at the lower rim adopts the cone conformation, and the tetrasubstituted products are formed in the 1,3-alternate conformation. © 2004 Springer Science+Business Media, Inc

    Ground-based acoustic parametric generator impact on the atmosphere and ionosphere in an active experiment

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    We develop theoretical basics of active experiments with two beams of acoustic waves, radiated by a ground-based sound generator. These beams are transformed into atmospheric acoustic gravity waves (AGWs), which have parameters that enable them to penetrate to the altitudes of the ionospheric E and F regions where they influence the electron concentration of the ionosphere. Acoustic waves are generated by the ground-based parametric sound generator (PSG) at the two close frequencies. The main idea of the experiment is to design the output parameters of the PSG to build a cascade scheme of nonlinear wave frequency downshift transformations to provide the necessary conditions for their vertical propagation and to enable penetration to ionospheric altitudes. The PSG generates sound waves (SWs) with frequencies f1 = 600 and f2 = 625 Hz and large amplitudes (100-420ms-1). Each of these waves is modulated with the frequency of 0.016 Hz. The novelty of the proposed analytical-numerical model is due to simultaneous accounting for nonlinearity, diffraction, losses, and dispersion and inclusion of the two-stage transformation (1) of the initial acoustic waves to the acoustic wave with the difference frequency Δf = f2 - f1 in the altitude ranges 0-0.1 km, in the strongly nonlinear regime, and (2) of the acoustic wave with the difference frequency to atmospheric acoustic gravity waves with the modulational frequency in the altitude ranges 0.1-20 km, which then reach the altitudes of the ionospheric E and F regions, in a practically linear regime. AGWs, nonlinearly transformed from the sound waves, launched by the two-frequency ground-based sound generator can increase the transparency of the ionosphere for the electromagnetic waves in HF (MHz) and VLF (kHz) ranges. The developed theoretical model can be used for interpreting an active experiment that includes the PSG impact on the atmosphere-ionosphere system, measurements of electromagnetic and acoustic fields, study of the variations in ionospheric transparency for the radio emissions from galactic radio sources, optical measurements, and the impact on atmospheric aerosols. The proposed approach can be useful for better understanding the mechanism of the acoustic channel of seismo-ionospheric coupling

    The expansion field: The value of H_0

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    Any calibration of the present value of the Hubble constant requires recession velocities and distances of galaxies. While the conversion of observed velocities into true recession velocities has only a small effect on the result, the derivation of unbiased distances which rest on a solid zero point and cover a useful range of about 4-30 Mpc is crucial. A list of 279 such galaxy distances within v<2000 km/s is given which are derived from the tip of the red-giant branch (TRGB), from Cepheids, and from supernovae of type Ia (SNe Ia). Their random errors are not more than 0.15 mag as shown by intercomparison. They trace a linear expansion field within narrow margins from v=250 to at least 2000 km/s. Additional 62 distant SNe Ia confirm the linearity to at least 20,000 km/s. The dispersion about the Hubble line is dominated by random peculiar velocities, amounting locally to <100 km/s but increasing outwards. Due to the linearity of the expansion field the Hubble constant H_0 can be found at any distance >4.5 Mpc. RR Lyr star-calibrated TRGB distances of 78 galaxies above this limit give H_0=63.0+/-1.6 at an effective distance of 6 Mpc. They compensate the effect of peculiar motions by their large number. Support for this result comes from 28 independently calibrated Cepheids that give H_0=63.4+/-1.7 at 15 Mpc. This agrees also with the large-scale value of H_0=61.2+/-0.5 from the distant, Cepheid-calibrated SNe Ia. A mean value of H_0=62.3+/-1.3 is adopted. Because the value depends on two independent zero points of the distance scale its systematic error is estimated to be 6%. Typical errors of H_0 come from the use of a universal, yet unjustified P-L relation of Cepheids, the neglect of selection bias in magnitude-limited samples, or they are inherent to the adopted models.Comment: 44 pages, 4 figures, 6 tables, accepted for publication in the Astronony and Astrophysics Review 15

    New materials based on tubular nanodimensional structures 1. Synthesis, structural studies and determination of interproton distances in solutions of functionalized thiacalix[4]arenes according to NMR spectroscopic data (NOESY)

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    New derivatives of p-tert-butylthiacalix[4]arene were synthesized. The conformation of the macrocycles and interproton distances in the synthesized thiacalix[4]arenes in solutions were determined by NMR spectroscopy. p-tert-Butylthiacalix[4]arene distally disubstituted at the lower rim adopts the cone conformation, and the tetrasubstituted products are formed in the 1,3-alternate conformation. © 2004 Springer Science+Business Media, Inc

    New materials based on tubular nanodimensional structures 1. Synthesis, structural studies and determination of interproton distances in solutions of functionalized thiacalix[4]arenes according to NMR spectroscopic data (NOESY)

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    New derivatives of p-tert-butylthiacalix[4]arene were synthesized. The conformation of the macrocycles and interproton distances in the synthesized thiacalix[4]arenes in solutions were determined by NMR spectroscopy. p-tert-Butylthiacalix[4]arene distally disubstituted at the lower rim adopts the cone conformation, and the tetrasubstituted products are formed in the 1,3-alternate conformation. © 2004 Springer Science+Business Media, Inc

    New materials based on tubular nanodimensional structures 1. Synthesis, structural studies and determination of interproton distances in solutions of functionalized thiacalix[4]arenes according to NMR spectroscopic data (NOESY)

    No full text
    New derivatives of p-tert-butylthiacalix[4]arene were synthesized. The conformation of the macrocycles and interproton distances in the synthesized thiacalix[4]arenes in solutions were determined by NMR spectroscopy. p-tert-Butylthiacalix[4]arene distally disubstituted at the lower rim adopts the cone conformation, and the tetrasubstituted products are formed in the 1,3-alternate conformation. © 2004 Springer Science+Business Media, Inc
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