MEASUREMENTS OF THE FLUX DENSITIES AND VARIABILITY OF THE STANDARD FLUX SCALE ''ARTIFICIAL MOON'' SOURCES ON TIME SCALES OF 1-8.5 YEARS
Section: ASTRONOMICAL INSTRUMENTS AND METHODS
Authors:
1.
Institute of Applied Astronomy of the Russian Academy of Sciences
2.
Institute of Applied Astronomy of the Russian Academy of Sciences
3.
Institute of Applied Astronomy of the Russian Academy of Sciences
4.
Institute of Applied Astronomy of the Russian Academy of Sciences
Type:
Сonference article
Published:
27.12.2024
Subject area:
UDC 52
UDC 520
UDC 53
UDC 521
UDC 523
UDC 524
UDC 52-1
UDC 52-6
CSCSTI 41.00
CSCSTI 29.35
CSCSTI 29.31
CSCSTI 29.33
CSCSTI 29.27
CSCSTI 29.05
Russian Classification of Professions by Education 03.06.01
Russian Classification of Professions by Education 03.05.01
Russian Classification of Professions by Education 03.04.03
Russian Library and Bibliographic Classification 2
Russian Library and Bibliographic Classification 223
Russian Trade and Bibliographic Classification 614
Russian Trade and Bibliographic Classification 6135
BISAK SCI004000 Astronomy
BISAK SCI005000 Physics / Astrophysics
UDC 520
UDC 53
UDC 521
UDC 523
UDC 524
UDC 52-1
UDC 52-6
CSCSTI 41.00
CSCSTI 29.35
CSCSTI 29.31
CSCSTI 29.33
CSCSTI 29.27
CSCSTI 29.05
Russian Classification of Professions by Education 03.06.01
Russian Classification of Professions by Education 03.05.01
Russian Classification of Professions by Education 03.04.03
Russian Library and Bibliographic Classification 2
Russian Library and Bibliographic Classification 223
Russian Trade and Bibliographic Classification 614
Russian Trade and Bibliographic Classification 6135
BISAK SCI004000 Astronomy
BISAK SCI005000 Physics / Astrophysics
Language:
English
Keywords:
methods: data analysis, observational; telescopes
Funding:
state budget
Abstract (English):
We present flux density measurements for the standard radio sources of the ``Artificial Moon'' (AM) absolute flux scale during the time interval of 2017.5–2024.0 at wavelengths $\lambda=3.5$ and $6.2$ cm. The standard sources are weakly variable, and maintaining the accuracy of the scale requires regularly recurring calibrations. Currently, the RT-32 radio telescope at the Svetloe Observatory of the Institute of Applied Astronomy of the Russian Academy of Sciences (IAA RAS) monitors the AM flux scale standard sources to study their variability and maintain the accuracy of the scale. We determined the flux densities of the AM flux scale calibrators at two wavelengths during the time interval of 2017.5–2024.0. The measurement errors for both wavelengths did not exceed $\pm2$%, the measurement data were averaged over time intervals of 1 year at the average epochs 2019.0, 2022.0, and 2023.0. A comparison of the standard source flux densities $S$ for the epochs 2019.0, 2022.0, and 2023.0 with each other as well as with the flux densities $S_0$ at the epoch 2015.5 has shown that at time intervals of more than 1 year, there exists variation in the standard source flux densities that exceeds the standard deviations $\sigma$ and the established flux scale error limits of $\pm3$%. We conclude that it is necessary to recalibrate the standard sources at least every 2 years to maintain the accuracy of the flux scale.
We present flux density measurements for the standard radio sources of the ``Artificial Moon'' (AM) absolute flux scale during the time interval of 2017.5–2024.0 at wavelengths $\lambda=3.5$ and $6.2$ cm. The standard sources are weakly variable, and maintaining the accuracy of the scale requires regularly recurring calibrations. Currently, the RT-32 radio telescope at the Svetloe Observatory of the Institute of Applied Astronomy of the Russian Academy of Sciences (IAA RAS) monitors the AM flux scale standard sources to study their variability and maintain the accuracy of the scale. We determined the flux densities of the AM flux scale calibrators at two wavelengths during the time interval of 2017.5–2024.0. The measurement errors for both wavelengths did not exceed $\pm2$%, the measurement data were averaged over time intervals of 1 year at the average epochs 2019.0, 2022.0, and 2023.0. A comparison of the standard source flux densities $S$ for the epochs 2019.0, 2022.0, and 2023.0 with each other as well as with the flux densities $S_0$ at the epoch 2015.5 has shown that at time intervals of more than 1 year, there exists variation in the standard source flux densities that exceeds the standard deviations $\sigma$ and the established flux scale error limits of $\pm3$%. We conclude that it is necessary to recalibrate the standard sources at least every 2 years to maintain the accuracy of the flux scale.
Keywords:
methods: data analysis, observational; telescopes
methods: data analysis, observational; telescopes
1. Finkelshtein A., 2001, Nauka v Rossii, 5, p. 20
2. Finkelshtein A., Ipatov A., Smolensev S., 2002, Proc. Fourth APSGP WorkShop, ed. H. Cheng, Q. Zhihan, p. 47
3. Ivanov V.P., Ipatov A.V., Rakhimov I.A., et al., 2018, Astronomy Reports, 62, p. 574
4. Rakhimov I., Akhmedov Sh., Zborovsky A., et al., 2001, All-Russian Astronomical Conference, Conference abstracts, p. 152
