David Kuridze (Aberystwyth): "High resolution mapping of the elusive magnetic field of the solar corona"
Abstract: The magnetic field is key to the dynamics, evolution, and heating of the solar atmosphere, yet direct measurements are rare and highly uncertain. In this seminar I will discuss about the techniques and challenges of measuring the magnetic field in the corona. I will then present the results from my current work where we report on the unique observations of the flaring coronal loops at the solar limb using high resolution imaging spectropolarimetry from the Swedish 1-meter Solar Telescope. The vantage position, orientation and nature of the chromospheric material that filled the observed flare loops allowed us to determine their magnetic field with unprecedented accuracy. Our analysis reveals coronal magnetic field strengths as high as 350 Gauss at heights up to 25 Mm above the solar limb. These measurements are substantially higher than a number of previous estimates and could have considerable implications for our current understanding of the extended solar atmosphere.