N. N. Kalinichenko Institute of Radio Astronomy, National Academy of Sciences of Ukraine, 4, Mystetstv St., Kharkiv, 61002 Ukraine
M. R. Olyak Institute of Radio Astronomy, National Academy of Sciences of Ukraine, 4, Mystetstv St., Kharkiv, 61002 Ukraine
O. O. Konovalenko Institute of Radio Astronomy, National Academy of Sciences of Ukraine, 4, Mystetstv St., Kharkiv, 61002 Ukraine
I. N. Bubnov Institute of Radio Astronomy, National Academy of Sciences of Ukraine, 4, Mystetstv St., Kharkiv, 61002 Ukraine
S. N. Yerin Institute of Radio Astronomy, National Academy of Sciences of Ukraine, 4, Mystetstv St., Kharkiv, 61002 Ukraine
A. I. Brazhenko Poltava Gravimetric Observatory, S. Subotin Institute of Geophysics, National Academy of Sciences of Ukraine, 27/29, Miasoiedov St., Poltava, 36029 Ukraine
O. L. Ivantishin Karpenko Physico-Mechanical Institute,
National Academy of Sciences of Ukraine,
5, Naukova St., Lviv, 79060 Ukraine
O. A. Lytvynenko Institute of Radio Astronomy, National Academy of Sciences of Ukraine, 4, Mystetstv St., Kharkiv, 61002 Ukraine