SHINE: Validating and Comparing Velocities Estimated from Magnetograms

University Of California-Berkeley, Berkeley CA

Investigators

Abstract

The Principal Investigator (PI) will investigate the accuracy of plasma velocities derived from solar photospheric and chromospheric magnetograms, using model data that more realistically simulates photospheric and chromospheric magnetic evolution. He will conduct these tests in collaboration with model developers and users of several velocity estimation methods. This study is motivated by the fact that magnetogram sequences are extensively used by the community to estimate velocities and the fluxes of magnetic energy and helicity into the solar corona, thereby driving dynamic models of the coronal magnetic field. However, synthetic magnetograms derived from magnetohydrodynamic (MHD) simulations of magnetoconvection in the solar interior have demonstrated that such magnetogram sequencing methods of estimating velocities are error prone. The PI will address several scientifically interesting questions, such as whether velocities are more accurately reconstructed from photospheric or chromospheric magnetograms, and whether current methods reconstruct the energy and helicity fluxes accurately. His coordinated analyses of magnetogram observations will determine how well the differing velocity estimation methods agree and how variations in instrumental spatial resolution affect these estimated velocities. The PI plans to hold annual workshops to promote research partnerships. He will post his synthetic and observed data sets on journal-hosted web sites to ensure widespread and long-term dissemination of his findings, and to permit standardized benchmarking of velocity estimation methods within the community. His research team will supervise students and introduce them to statistical methods of data analysis. This work will lead to enhanced predictive space weather capabilities, and thereby impact society through better forecasts for solar disturbances that propagate to Earth and affect our technological infrastructure.