The spectrophotometrical complex of the 6-m telescope in Nasmyth-1 focus
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The spectrophotometrical complex in Nasmyth-1 focus consists of:
- the 2*1024-channel photon counter (IPCS) set on the modernized
spectrograph SP-124;
- the 1024*1024-panoramic CCD detector (CCD-camera) providing the
observational rate of the "long slit" mode;
- the electrophotometer ("NЕP-1") set before the slit part of the
spectrograph;
- the hard/software MANIA complex (Multichannel Analysis of Nanosecond
Intensity Alterations; see the description on the separate desk);
- an automated control and acquisition system.
The complex is intented for the spectral observation with low
and moderate resolution and for simultaneous spectral and photometrical
observation in different modes with a time resolution up to 30 ms
for the registered spectra, 1 ms for the classical photometry and up to
20 ns given the special registration complex MANIA is used.
Having its integral possibilities to provide simultaneous spectral and
photometrical observations in different modes, the complex is a unique
device in the world.
The treating of the obtained data is performed with the software developed
in the SAO and working in MIDAS European system. All observations with the
spectrophotometrical complex are conducted remotely in the automatic regime from
the remote control room of the 6-m telescope.
During the use of the complex, which is the oldest digital device of the BTA
(1983-1996), there were:
- 891 observation nights conducted;
- 13473 different observations obtained;
- the file size of the archive data of 420 Mb stored.
Important scientific achievements were obtained with the complex
During the complex use the following important scientific results were
obtained:
The studying of the active extragalactic objects:
- A new sample of about 300 quasars with the redshift range of
z=0.2 \div 3.2 and about 80 Syfert galaxies from the Second Byurakan
Survey was built that allows to review the space densities of the
active extragalactic objects and their evolution.
- since 1986 till 1996 the monitoring of the core spectrum of the bright
Syfert galaxy NGC 4151 had been conducted. Resulting from more that 500
spectra in the H-beta region, there was revealed that some spectra
features can be narrow components of the H-beta and H-delta lines and
HeII-lambda 4686 line with the radial velocities of -7500 and +9500
km/sec.
A quasiperiodical behaviour of the variation of the broad emission line
HeII-lambda 4686 assymetry with the character time of about 2 years was
discovered. The observed spectral variations can be explained by the model
of the relativistic rejection of substance from the galactic core.
- In 1996 a new internation project (with the Astronomical Institute
of Potsdam, Germany) on optical identification of X-ray sources has been
started. The preliminary observations of this program on 6-m telescope
has allowed to discover more that 50 active extragalactic obgects.
Investigation of the blue compact galaxies:
- A new sample of 360 blue compact galaxies with a strong star formation
was build on the base of the Second Byurakan Survey.
Having analysed it a new galaxy SBS 0335-052 with the minimum abundance
of heavy elements was discovered. The detailed spectral studying of the
galaxy showed that it is the youngest galaxy among the near objects in
the Universe so far.
- More that 20 galaxies with the extremely low-abundances of heavy
elements in the range of 1/30-1/10 of the Sun's one, were found.
They were used to measure the new value of the primordial Helium
abundance Y_p=0.230 pm 0.003, which corresponds to the standard models
of the Big Bang.
- There was shown that the space distribution of the sample objects differs
from the distribution of normal bright galaxies that partially confirms the
modern cosmological theories of galaxy origin in the presence of invisible
"dark" substantion.
Investigation of relativistic star objects:
- During the 15-years observation term near 500 spectra of the unique
source SS~433, from which the relativistic jets were found for the first
time, were obtained. Having the radial velocities of the HeII 4686 line
the mass of the relativistic star of M=5.3 \div 10.7 Sun's mass
was found that allows to consider it as a black hole.
The orbital and precession radial velocity curves of permanent emission
lines were obtained. Their analysis allowed to understand the structure
of a "overcritical" accrection disk. For this object the spiral waves
in the accrection disk were found for the first time.
The physical parameters of the SS~433 relativistic jets, which are
the most intriguing puzzle of the XX-century astronomy, were determined.
In the jets with the 1^\circ spread the gas components are ejected
with the velocity equal to 1/4 of the light one. Their density is
10^{13} cm ^{-3}, the electronic temperature is 15000 K,
the kinetic energy taken away in a time unit is
10^{-39} erg/sec, that is 100000 times as big as the Sun's luminosity.
- In 1992-1993 a unique eclipsing binary star NN Ser, that has the
deeppest known eclipse of more that 6 magnitudes, was studied.
This sistem applies to the type of predecessors of cataclismic eruptiv
variables. It is shown that the intensities and radial velocities
of hydrogen and helium emissiones lines vary with a period phase
and up to their complete disappearance near the main eclipse.
For the first time we succeded in precise localisation of the origin
region of these lines as a spot on the dwarf star surface that arises
as a result of the heating by the adjacent component - hot white
dwarf star.
- In the intermediate brighness state of AM Her the 4.5--minutes
brightness fluctuations of large amplitude (60\%), that exist
the most part of the orbital cycle, were found.
Such 5-10 minutes quasiperiodic brightness fluctuations of polars
can be explained by a superposition of regular periodic oscillations,
the brightness variations of continuum and emission lines vary
negligibly.
Some illustrations (light curves, spectra) of the data obtained with
this complex are shown on the desc of the laboratory of Relativistic
Astrophysics.
"Structure" participants:
- Lipovetsky V.A.
- Neizvestnij S.I.
- Ugryumov A.V.
- Kniazev A.Y.
The project was conducted in collaboration with :
- Sherggin V. - SAO RAS
- Zinkovsky V. - SAO RAS
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26 September 1996