Study of the 1 divided by f Maia Brodiano, Facundo Pugliese, Nahuel Andrés, Pablo Dmitruk

We investigate the appearance of a low-frequency

magnetic spectrum in three-dimensional incompressible magnetohydrodynamic turbulence using direct numerical simulations and virtual spacecraft sampling. Our goal is to determine how the measured temporal spectra depend on the mean magnetic guide field, the probe velocity relative to the Alfvén speed and the sampling angle with respect to the guide field. We find that the clearest

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ranges are obtained for stronger guide fields and are favoured by faster sampler trajectories oriented more nearly perpendicular to the mean magnetic field. To characterise this behaviour, we introduce a quantitative score that measures the quality and spectral coverage of the detected

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interval. We further show that, as the probe speed increases, the measured temporal spectra become progressively more consistent with the corresponding Eulerian spectra at intermediate and high wavenumbers for both parallel and perpendicular sampling directions, particularly in the strong guide field case. These results indicate that the presence and clarity of a temporal

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range depend not only on the underlying turbulent dynamics, but also on the geometry and speed of the sampling process, with implications for the interpretation of low-frequency in situ measurements in the solar wind.