edu.ucar.opensky::articles:18234 UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact 2025-12-26T03:28:26.497873 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) https://n2t.org/ark:/85065/d7833tkb Validating time-distance helioseismology with realistic quiet-sun simulations 2014-05-28T00:00:00Z publication https://n2t.org/ark:/85065/d7833tkb https://doi.org/10.1088/0004-637X/788/2/127 DeGrave, K. author Jackiewicz, J. author Rempel, Matthias author UCAR/NCAR - Library publisher Linear time-distance helioseismic inversions are carried out for vector flow velocities using travel times measured from two ~100² Mm² × 20 Mm realistic magnetohydrodynamic quiet-Sun simulations of about 20 hr. The goal is to test current seismic methods on these state-of-the-art simulations. Using recent three-dimensional inversion schemes, we find that inverted horizontal flow maps correlate well with the simulations in the upper ~3 Mm of the domains for several filtering schemes, including phase-speed, ridge, and combined phase-speed and ridge measurements. In several cases, however, the velocity amplitudes from the inversions severely underestimate those of the simulations, possibly indicating nonlinearity of the forward problem. We also find that, while near-surface inversions of the vertical velocities are best using phase-speed filters, in almost all other example cases these flows are irretrievable due to noise, suggesting a need for statistical averaging to obtain better inferences. UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact PDF Text theme Resource Type 2016-01-01T00:00:00Z publication An edited version of this article was published by the Institute of Physics on behalf of the American Astronomical Society. Copyright 2014 the American Astronomical Society. None eng geoscientificInformation