Observing the Sun with ALMA: A New Window into Solar Physics

The Atacama Large Millimeter/Submillimeter Array (ALMA) is a joint North American, European, and East Asian interferometric array that opens the mm-submm wavelength part of the electromagnetic spectrum for general astrophysical exploration, providing high resolution imaging in frequency bands. Despite being a general purpose instrument, provisions have been made to enable solar observations with ALMA, thereby offering a new window into solar physics. Radiation emitted at ALMA wavelengths originates mostly from the chromosphere, which plays an important role in the transport of energy and matter and the heating of the outer layers of the solar atmosphere. Despite decades of intensive research, an understanding of the chromosphere is still elusive, and challenging to observe owing to the complicated formation mechanisms of currently available diagnostics. ALMA will change the scene substantially as it serves as a nearly linear thermometer at high spatial, temporal, and spectral resolution, enabling us to study the complex interaction of magnetic fields and shock waves and yet-to-be-discovered dynamical processes.Moreover, ALMA will play an important role in the study of energetic emissions associated with solar flares at sub-THz frequencies.This presentations introduces ALMA to the solar physcis community and motivates the science that can be addressed by ALMA using a number of examples based on 3D MHD simulations. In addition, the means by which ALMA is used to acquire and calibrate solar observations will be discussed. Finally, we encourage potential users to join us in further defining and articulating the exciting science to be explored with this fundamentally new instrument.