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Поисковые слова: lunar module
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Radio
Astronomical
Telescope
Academy
Nauk (science) of Russia is one of the two big
telescope of Special Astrophysical Observatory. BTA and RATAN-600
are largest optical and radio telescopes in Russia.
RATAN has seen 'first light' from source PKS 0521-36
12 July 1974 .
Since more 50000 observations were caried out in continuum.
Main advantage of the telescope is multi-frequiency (1 - 31 cm wavelength) and
high bright temperature sensitivity.
Antenna of RATAN radio telescope consist of 576-m circle of 895 elements
(2 x 11.5 m), which could use as four independent sectors (225 elements) of
that reflector (named: North, South, West and East). Four different
feed-cabines (N1,2,3,5) with secondary mirrors could simulteniously
collect radio emission from these four sectors and be used in programs
of Continuum , Spectral and Solar observations.
In 1999 feed-cabine #5 will use for mixed continuum/spectral programs.
In 1999 feed-cabine #6 will use for mixed continuum/solar programs.
With central rail-way rotation circle
the feed-cabines could be move in any of 12 fixed azimiths.
But in 1999 only azimuths 0, 30, 180 and 270o can be used in
observations.
In 1985 a new conical mirror and feed-cabine N6 was firstly used.
That feed-cabine aloows to collect radio emission from whole circle,
but range of source declinations limited in this regime the zone of
zenith distance z=+-6o (or Dec: 38-49o).
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General view of telescope.
Click on left mouse button to see the short describing of the elements of RATAN-600.
Geographic coordinates of the RATAN center, as
measured with astrometric observations in 1968 Juanary:
latitude (phi) |
43o 49' 52".75±0".16 |
longitude |
-02h46m22.1s or -41о 35' 31".5 |
hight from sea level |
970 m |
A0 H = (90 - phi) + delta = 46o10'07".25 + delta
A180lc H = -(90 - phi) + delta = -46o10'07".25 + delta
A180uc H = (90 + phi) - delta = 133o49'52".75 - delta
Closing angles by mountains:
Azimuth | Hmax | Directions |
0o | 2o16'52" | in North |
90o | 2o07'00" | in East |
180o | 3o19'30" | in South |
270o | 2o39'00" | in West |
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Techniques of observations
- Usualy the transit regime of source through unmoving
direction diagram (beam) of telescope. That regime is fitted
for big list of sources or for survey on fixed elevation.
- Regime of 'unmoved focus' with one sector is fitted for
massive observations of sources in range of nearby declinations:
2-3o for DEC = 0 and 10o -
for declination: -30o. In this case feed-cabine became
in the same position, thus no movement or ajustment of horizon.
Accuracy of determination of RA and DEC improves to 3-10".
Affective area of one sector is near 1000 m in square.
- Since of 1996 the current regime of 'sliding' with
effective time of collection of 60-100 second.
If you know coordinates of object
you could decrease threshold of determination
of radio emission. his regime could use anly with North or South
sectors.
- Regime "Zenith" is observation with feed-cabine N6 and whole
circle, but is not in the plan of 1997.
- Regime "Atmosphere" is vertical cross-cuts for detrermination
absorbtion in atmosphere, it needs only
1-2 cross-cuts-removing of antenna from 5 to 30o.
Trushkin, satr@sao.ru LabRAO SAO 1999
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