Space-Weather Broadening of Narrow Radio Signals: Implications for SETI Searches and M-Dwarf Targets

To the point

Space weather around stars can smear and broaden a very narrow radio signal as it travels, weakening its peak and making searches for razor-thin spectral spikes miss it, and using radio transmissions from our solar system helps estimate how much broadening occurs for different star types, especially M-dwarfs, so future searches should look for wider signals and use higher radio frequencies to mitigate the effect.