51 research outputs found
Anisotropy of the space orientation of radio sources. I: The catalog
A catalog of the extended extragalactic radio sources consisting of 10461
objects is compiled based on the list of radio sources of the FIRST survey. A
total of 1801 objects are identified with galaxies and quasars of the SDSS
survey and the Veron-Veron catalog. The distribution of the position angles of
the axes of radio sources from the catalog is determined, and the probability
that this distribution is equiprobable is shown to be less then 10^(-7). This
result implies that at Z equal to or smaller then 0.5, spatial orientation of
the axes of radio sources is anisotropic at a statistically significant level.Comment: 8 pages, 7 figure
Optical Spectra of Four Objects Identified with Variable Radio Sources
We obtained optical spectra of four objects identified with variable radio
sources. Three objects (0029+0554, 0400+0550, 2245+0500) were found to be
quasars with redshifts of 1.314, 0.761, and 1.091. One object (2349+0534) has a
continuum spectrum characteristic of BL Lac objects. We analyze spectra of the
radio sources in the range 0.97-21.7 GHz for the epoch 1997 and in the range
3.9-11.1 GHz for the epoch 1990, as well as the pattern of variability of their
flux densities on time scales of 1.5 and 7 years.Comment: 4 pages, PD
Optical transition radiation in fused quartz under external acoustic field
In the present paper we have investigated the optical transition radiation in a plate excited by a longitudinal acoustic wave. The spectral-angular density of the radiated energy is calculated. The numerical examples are given for
a plate of fused quartz. These results show that the acoustic waves allow to control the parameters of the radiation. In particular, new resonance peaks appear in the
spectral distribution of the radiation intensity. The height of the peaks can be tuned by choosing the parameters of the acoustic wave
Experimental investigation of optical transition radiation in amorphous quartz
Optical transition radiation (OTR) in amorphous quartz is investigated experimentally for electrons with energies 7.5MeV. It is shown that the Cherenkov radiation and OTR can be separated at specific conditions. The linear
polarization of OTR is investigated and it is shown that the polarization is radial. The results of measurements for the spectral distribution of OTR have shown the maximum intensity of radiation at the wavelengths in the range 320–500 nm
Small telescopes being effective: MAGIC or not?
The paper describes the MAGIC multi-mode focal reducer (Monitoring of Active
Galaxies by Investigation of their Cores), commissioned on the 1-m Zeiss-1000
telescope of the Special Astrophysical Observatory of the Russian Academy of
Sciences in September 2020. Three observational modes are currently realised:
photometry, polarimetry, and long-slit spectroscopy. Reducing the focal length
makes it possible to obtain a sufficiently large field of view for photometry
and a large slit height for spectroscopy of 12, as well as a large
field of view for polarimetry with a quadrupole Wollaston prism of
6.4. This feature makes the complex study of extended nebulae and
galaxies efficient. The MAGIC capabilities are presented in examples of
observations of various astronomical objects. The spectral mode in the range of
4000-7200 AA provides the spectral resolution 1000; for a starlike
target up to 14 mag in medium-band filters with a seeing of 1 for 20
minutes of total exposure, the photometry accuracy is better than 0.01 mag and
the polarization accuracy is better than 0.6%. Especially for the new focal
reducer, an offset guide and a position angle rotation system were implemented.
The results of the modernization of the baffle system in the optical scheme of
the telescope for the suppression of scattered light are also described
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