A.S. Sargsyan1

1 National Polytechnic University of Armenia (Yerevan, Armenia)

The Herouni Mirror Radio Optical Telescope (ROT-54/2.6) is placed on the southern slot of mount Aragats in Armenia. The author and chief designer of the radio telescope is Academician of the National Academy of Sciences of the Republic of Armenia, Doctor of Technical Sciences, Professor Paris Herouni. This is a unique instrument, known in international scientific circles as the Heruni Mirror Telescope (ROT-54/2.6). It is a large two-mirror spherical antenna with a diameter of 54 meters, combined with an optical telescope with a diameter of 2.6 m. A number of ROT-54/2.6 parameters, such as sensitivity and low antenna noise temperature, are significantly better than those of antennas of other large radio telescopes in the world.

Formulation of the problem: re-preservation, restoration and restart of the antenna of the ROT-54/2.6 radio-optical telescope works will begin in the near future. That is unique structure built in the late 80s. The process of re-preservation and restoration involves the solution of a number of important tasks of both research and experimental nature. Along with the development of a new control system for the moving part of the antenna in order to scan the antenna pattern, the modernization of the power supply system, etc., one of the priorities will be the complex adjustment of the antenna.

Goal: explore the possibilities of organizing and conducting the preliminary stage of adjustment work and describe in detail the methodology of the main measurements.

Results: a procedure for carrying out work on the preliminary adjustment of the antenna of the Herouni mirror radio telescope has been prepared and described in detail. The paper describes the method of work on the preliminary stage in the process of complex adjustment of the antenna, in particular: determining the center of the hemispherical dish of the antenna and checking the alignment of the center of rotation of the suspension system of a small mirror with the center of the sphere in order to ensure the possibility of fixing the geometric axis of the mirror in the future. The technique is based on the use of distance measurement using optical devices, such as laser rangefinders.

Practical value: based on the results of the study, as soon as the work on the restoration and restart of the ROT-54/2.6 is started, the first phase of antenna adjustment will be carried out according to the instructions presented in the methodology based on the use of optical distance measuring devices.

A necessary component of any methodology is an assessment of the accuracy achieved when using it. This method will ensure that the accuracy required for full-scale adjustment of large reflector antennas with a homologous reflector system for operation in the centimeter and millimeter bands is maintained. Thus, upon completion of the preliminary adjustment work on the antenna, it will be the turn to adjust the panel surface of the main spherical reflector. The methodology for this next phase of antenna alignment will also be based on the use of optical distance measuring devices.

Sargsyan A.S. Method of the ROT-54/2.6 antenna de-conservation preliminary phase adjustment process. Radiotekhnika. 2023. V. 87. № 2. P. 172−177. DOI: https://doi.org/10.18127/j00338486-202302-20 (In Russian)

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