We present a systematic study of the temperature dependence of diffusivemagnon spin transport, using a non-local device geometry. In our measurements,we detect spin signals arising from electrical and thermal magnon generation,and we directly extract the magnon spin diffusion length $\lambda_m$ fortemperatures from 2 to 293 K. Values of $\lambda_m$ obtained from electricaland thermal generation agree within the experimental error, with$\lambda_m=9.6\pm0.9$ $\mu$m at room temperature to a minimum of$\lambda_m=5.5\pm0.7$ $\mu$m at 30 K. Using a 2D finite element model to fitthe data obtained for electrical magnon generation we extract the magnon spinconductivity $\sigma_m$ as a function of temperature, which is reduced from$\sigma_m=5.1\pm0.2\times10^5$ S/m at room temperature to$\sigma_m=0.7\pm0.4\times10^5$ S/m at 5 K. Finally, we observe an enhancementof the signal originating from thermally generated magnons for lowtemperatures, where a maximum is observed around $T=7$ K. An explanation forthis low temperature enhancement is however still missing and requiresadditional investigations.
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