|17th of April 2018|
|ATCA observations of Alpha Centauri|
Alpha Centauri is the closest star system to the solar system, and
consists of three stars: Alpha Centauri A, Alpha Centauri B, and
Proxima Centauri (also known as Alpha Centauri C). At radio
wavelengths, stars like the sun are not strong radio sources, but they
do emit radio waves via several emission processes. Trigilio et al.
observed the Alpha Centauri system with the Australian Telescope
Compact Array at 2 GHz and 17 GHz, detecting both Alpha Centauri A and
B at 17 GHz.
The claimed detection of an Earth size planet in close orbit to Alpha Centauri B, although doubtful, opens the opportunity to check the existence of Star-Planet Magnetic Interaction (SPMI). This could trigger Auroral Radio Emission due to Electron Cyclotron Maser in the stellar corona, similar to the interaction between Jupiter and its satellie Io, which is very intense, polarized and highly beamed. However, no hints of SPMI were found in these observations. The image above shows the field around Alpha Centauri at 17 GHz. The large circles labeled A and B indicate the two stellar components.
More details are given in the preprint of the paper.