In the present paper, recent measurement results of refurbished Irbene RT-16 radio telescope receiving system performance are presented. The aim of the research is to evaluate characteristics of RT-16, which will allow carrying out necessary amplitude calibration in both single dish and VLBI observations, to improve the performance of existing system as well as to monitor, control and compare performance if possible changes in the receiving system will occur in future. The evaluated receiving system is 16 m Cassegrain antenna equipped with a cryogenic receiver with frequency range from 4.5 to 8.8 GHz, which is divided into four sub-bands. Multiple calibration sessions have been carried out by observing stable astronomical sources with known flux density by using in-house made total power registration backend. First, pointing offset calibration has been carried out and pointing model coefficients calculated and applied. Then, amplitude calibration, namely antenna sensitivity, calibration diode equivalent flux density and gain curve measurements have been carried out by observing calibration sources at different antenna elevations at each of the receiver sub-bands. Beam patterns have also been evaluated at different frequency bands. As a whole, acquired data will serve as a reference point for comparison in future performance evaluation of RT-16.
Lütfiye Tutkun, Servet Birgin İritaş, Serdar Deniz, Özgür Öztan, Sedat Abuşoğlu, Ali Ünlü, Vugar Ali Türksoy and Sultan Pınar Çetintepe
environment. Samples were stored at -20 °C until analysis. IL-6 and TNF-α levels were then studied by dissolving the samples. ELISA Kits (DIA-source, catalogue numbers: KAP1261 and KAP1751, respectively) were used for IL-6 and TNF-α analyses. After the necessary pre-treatments had been made, samples were placed on microplates. Afterwards, microplates were carried to an ELISA (BMG LAB-TECH ClarioStar model) for reading. The wavelength was set at 450 nm. 5-pointcalibration curves were used for IL-6, and TNF-α measurements. The r 2 values of the calibration curves were