Astronomy and astrophysics

Twist, loops, jets, beams and flares: new views of the solar chromosphere and transition region with IRIS

by Bart De Pontieu (Lockheed Martin Solar & Astrophysics Laboratory)

Europe/Stockholm
FB55

FB55

Description
The Interface Region Imaging Spectrograph (IRIS) was launched in June 2013 and has been obtaining high-resolution (0.33 arcsec) spectra and images of the Sun's chromosphere and transition region since end of July 2013. Our speaker will describe the IRIS instrument and its diagnostics, which include strong lines in the far-ultraviolet (e.g., C II 1335, Si IV 1402) and near-ultraviolet (Mg II k 2796 and Mg II h 2803). Our speaker will present an overview of recent IRIS results, including: 1. detection of small-scale and dynamic transition region loops that were previously unresolved but whose existence had been hypothesized to explain the excess brightness in the transition region (so-called "unresolved fine structure"), 2. the pervasiveness of twist on very small scales in the chromosphere and transition region on a variety of different dynamic features , 3. exploiting observations of the chromospheric response to coronal energy deposition to help constrain the coronal heating mechanism, 4. spatio-temporal characterization of the dominant heating mechanism in the chromosphere including effects from ion-neutral interactions, 5. first results on flares and coronal mass ejections.