volume | PIER Journals

Abstract

Solar hydrogen line emission has been observed at the frequency of 1.42 GHz (21 cm wavelength) with 3 m radio telescope installed inside the University of Baghdad campus. Several measurements related to the sun have been conducted and computed from the radio telescope spectrometer. These measurements cover the solar brightness temperature, antenna temperature, solar radio flux, and the antenna gain of the radio telescope. The results demonstrate that the maximum antenna temperature, solar brightness temperature, and solar flux density are found to be 970 K, 49600 K, and 70 SFU respectively. These results show perfect correlation with recent published studies.

1. Joardar, S., S. Bhattacharyya, A. B. Bhattacharyya, and C. R. Datta, "Radio astronomy and super synthesis a survey," Progress In Electromagnetic Research B, Vol. 22, 73-102, 2010.
doi:10.2528/PIERB10032105

2. Usoslin, I. G., "A history of solar activity over millennia. Living rev.," Solar Physics, Vol. 5, No. 3, 6-19, 2008.

3. Sehorst, C. L., A. V. Silva, and J. E. Costa, "Solar atmospheric model with spicules applied to radio emission," Astronomy and Astrophysics, Vol. 433, 365-374, 2005.
doi:10.1051/0004-6361:20042043

4. Shibasaki, K., C. E. Alissandrakis, and S. Pojolainen, "Radio emission of the quiet sun and active regions," Solar Physics, Vol. 273, 309-337, 2011.
doi:10.1007/s11207-011-9788-4

5. Labrum, N. R., "The radio brightness of quiet sun at 21 cm wavelength near sunspot maximum," Australia Journal Physics, Vol. 13, 700-711, 1960.
doi:10.1071/PH600700

6. Krishnan, T. and N. R. Labrum, "The radio brightness distribution on the sun at 21 cm from combined eclipse and pencil-beam observation," Australia Journal Physics, Vol. 14, 403-419, 1961.
doi:10.1071/PH610403

7. Shimabukuro, F. I. and J. M. Stacey, "Brightness temperature of the quiet sun at centimeter and millimeter wavelengths," The Astrophysical Journal, Vol. 152, 777-782, 1968.
doi:10.1086/149594

8. Zirin, H., B. M. Baumert, and G. J. Hurforf, "The microwave brightness temperature spectrum of the quiet sun," The Astrophysical Journal, Vol. 370, 779-783, 1991.
doi:10.1086/169861

9. Kuseki, R. A., "The solar brightness temperature at millimeter wavelength," Solar Physics, Vol. 48, 41-48, 1976.
doi:10.1007/BF00153329

10. Dulk, G. A. and D. E Gary, "The sun at 1.4 GHz: Intensity and polarization," Astronomy and Astrophysics, Vol. 124, 103-107, 1983.

11. Nakariakov, V. M., L. K. Kashapova, and Y. H. Yan, "Editorial: Solar radiophysics-recent results on observations and theories," Research in Astronomy and Astrophysics RAA, Vol. 14, No. 7, 1-6, 2014.
doi:10.1088/1674-4527/14/7/001

12. Tan, C., Y. Yan, B. Tan, Q. Fu, Y. Lin, and G. Xu, "Study of calibration of solar spectrometer and the quiet sun radio emission," The Astrophysical Journal, Vol. 808, No. 61, 21-41, 2015.

13. Wilson, T. L., K. Rohlfs, and S. Huttemeister, Tools of Radio Astronomy, 6th Ed., Springer-Verlag Berlin Heideelberg, 2013.
doi:10.1007/978-3-642-39950-3

14. Ptatap, P. and G. Mclntosh, "Measurements of the radiation from thermal and non thermal radio sources," American Association of Physics Teachers, Vol. 73, No. 5, 399-404, 2004.

15. Neil, K. O., "Single dish calibration techniques at radio wavelength," Astronomical society of the Pacific ASP Conference Series, Vol. 278, San Francisco, CA, 2001.

16. Saha, S. K., Diffraction-limited Imaging with Large and Moderate Telescopes, World Scientific Publishing Co. Pte. Ltd, 2007.
doi:10.1142/6492

17. Pacini, A. A. and J. P. Raulin, "Solar radio emission," Advances in Space Research, Vol. 35, 793-754, 2005.

18. Gary, D. and C. Keller, Solar and Space Weather Radio Physics Current Status and Future Developments , Springer Science + Business Media, INC, 2005.
doi:10.1007/1-4020-2814-8

19. Kalinov, V., "Solar observations with the small radio telescope," Bulgarian Astronomical Journal, Vol. 15, 107-112, 2011.

20. Zaineb, A. J. and K. M. Abood, "Study of some parabolic radio telescope antenna parameter," Iraqi Journal of Science, Special issue, Part B, 453-461, 2016.

21. Hoobi, M. R. and K. M. Abood, "Calibration of a three meter small radio telescope in baghdad university using the sun as a reference source," Iraqi Journal of Science, Vol. 60, No. 1, 171-177, 2019.

22. Abood, K. M. and A. M. Kitas, "Background radio emissions at 1.42 GHz," Iraqi Journal of Science, Vol. 59, No. 2A, 786-791, 2018.

23. Goodman, J. W., Statistical Optics, John Willy & Sons, Inc., New York, 2000.

24., http://www.spaceweather.gc.ca/sx-11-eng.php.

25., Massachusetts Institute of Technology Haystack Observatory.

26. Milligan, T. A., Modern Antenna Design, 2nd Ed., A John Wiley & Sons, Inc., 2005.
doi:10.1002/0471720615

27. Balanis, C. A., Antenna Theory Analysis and Design, 3rd Ed., JohnWiley & Sons, Inc., 2005.

Dr. Uday E. Jallod

Dr. Kamal M. Abood