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Following from the results of the first systematic modern low frequency Search for Extraterrestrial Intelligence (SETI) using the Murchison Widefield Array (MWA), which was directed toward a Galactic Center field, we report a second survey toward a Galactic Anticenter field. Using the MWA in the frequency range of 99 to 122 MHz over a three hour period, a 625 sq. deg. field centered on Orion KL (in the general direction of the Galactic Anticenter) was observed with a frequency resolution of 10 kHz. Within this field, 22 exoplanets are known. At the positions of these exoplanets, we searched for narrow band signals consistent with radio transmissions from intelligent civilisations. No such signals were found with a 5-sigma detection threshold. Our sample is significantly different to the 45 exoplanets previously studied with the MWA toward the Galactic Center Tingay et al.(2016), since the Galactic Center sample is dominated by exoplanets detected using microlensing, hence at much larger distances compared to the exoplants toward the Anticenter, found via radial velocity and transit detection methods. Our average effective sensitivity to extraterrestrial transmiter power is therefore much improved for the Anticenter sample. Added to this, our data processing techniques have improved, reducing our observational errors, leading to our best detection limit being reduced by approximately a factor of four compared to our previously published results.
Electron density irregularities in the ionosphere are known to be magnetically anisotropic, preferentially elongated along the lines of force. While many studies of their morphology have been undertaken by topside sounding and whistler measurements,
Significant new opportunities for astrophysics and cosmology have been identified at low radio frequencies. The Murchison Widefield Array is the first telescope in the Southern Hemisphere designed specifically to explore the low-frequency astronomica
Following the results of our previous low frequency searches for extraterrestrial intelligence (SETI) using the Murchison Widefield Array (MWA), directed toward the Galactic Centre and the Orion Molecular Cloud (Galactic Anticentre), we report a new
It is shown that the excellent Murchison Radio-astronomy Observatory site allows the Murchison Widefield Array to employ a simple RFI blanking scheme and still calibrate visibilities and form images in the FM radio band. The techniques described are
The Sun has remained a difficult source to image for radio telescopes, especially at the low radio frequencies. Its morphologically complex emission features span a large range of angular scales, emission mechanisms involved and brightness temperatur