Event DetailsEvent Dates: Monday, April 1, 2013 - 4:00pmSeminar Location: JILA AuditoriumSpeaker Name(s): Rebecca Centeno ElliottSpeaker Affiliation(s): High Altitude Observatory, NCAR Seminar Type/SubjectScientific Seminar Type: Astrophysical & Planetary Sciences ColloquiaEvent Details & Abstract: On the brink of solar maximum, there is a rising awareness of the impacts of Space Weather on human technological development. However, our prediction capability is limited by the extent of our understanding of the mechanisms that drive space weather events and how accurately we can model them. Underlying all of this is a more basic challenge: measuring the full magnetic topology of the active regions that drive coronal mass ejections and flares. The polarization of spectral lines encodes information about the magnetic properties of the plasma in which they are formed. Deciphering this information is the cornerstone for an accurate measurement of the strength and topology of these magnetic fields. The generation of spectral line polarization occurs through a variety of mechanisms (not only the well known Zeeman effect) that become more or less relevant depending on the particular physical scenario under consideration. I will review the most important diagnostic and interpretation techniques and show what we can achieve using these methods. While there is no shortage of challenges and limitations, future opportunities are hiding around the corner, especially in the advent of ATST and the suite of instruments that it will carry.