Research Highlights

Research Highlights

A selection of highlights culled from publications by HAO staff.
Inversion of an average synthetic Mg II k spectrum

Using the Hanle Effect in Mg II k to Quantify the Open Flux above the Solar Poles

Ryan A. Hofmann, David Afonso Delgado, Rebecca Centeno, Roberto Casini, Matthias Rempel, Tanausu del Pino Aleman test the use of the Mg II resonant lines for measurement of the magnetic field at the top of the chromosphere of polar coronal holes (CHs).

DKIST-MURaM observations

The Striated Solar Photosphere Observed at 0.″03 Resolution

Matthias Rempel, et al., analyze images acquired with the Visible Broadband Imager using the G-band channel to investigate the characteristics of fine-scale striations in the photosphere and compare them with state-of-the-art radiation-MHD simulations at similar spatial resolution. The striation patterns can be used as valuable diagnostics for studying the finest-scale structure of the photospheric magnetic field.

Scatter plot image

The role of the Lorentz force in sunspot equilibrium

J. M. Borrero; A. Pastor Yabar; M. Schmassmann; M. Rempel; M. van Noort; M. Collados apply the FIRTEZ Stokes inversion code to spectropolarimetric observations to infer the magnetic and thermodynamic parameters in two sunspots located at the disk center. Their research helps to explain why sunspots are such long-lived structures capable of surviving on the solar surface for days or even full solar rotations.

Impact of increasing greenhouse gases on the ionosphere and thermosphere

Impact of increasing greenhouse gases on the ionosphere and thermosphere response to a May 2024-like geomagnetic superstorm

N. M. Pedatella, H. Liu, H.-L. Liu, A. Herrington, and J. McInerney focus on understanding how changes in the background state of the upper atmosphere due to increases in CO2 alter the response of the ionosphere and thermosphere to geomagnetic storms finding that increasing levels of CO2 generally result in a weaker response of the ionosphere and thermosphere to geomagnetic storms in absolute terms, while their relative responses enhance at higher CO2 levels.

interhemisphere coupling simulated by WACCM6

Seasonal and Interannual Variation of the Interhemispheric Coupling during the Austral Winter in WACCM6

Dai Koshin, Nick Pedatella, and Anne Smith describe the coupling between the winter stratosphere in the Southern Hemisphere and the northern upper mesosphere as seen in a long-term whole atmosphere model simulation revealing interannual variation is associated with the phase of the intraseasonal oscillation in the equatorial mesosphere and lower thermosphere.

Global-scale toroid patterns

Mother's Day Superstorms: Pre- and Post-storm Evolutionary Patterns of AR 13664/8

Mausumi Dikpati, Marianna B. Korsos, Aimee A. Norton, Breno Raphaldini, Kiran Jain, Scott W. McIntosh, Peter A. Gilman, Andre S. W. Teruya and Nour E. Raouafi analyzed active region (AR) 13664 during a superactive emergence event. They conclude that this superstorm was caused by enhanced magnetic complexity occurring due to intricate interactions among multiple active regions emerging at nearly the same locations. 

multifluid MAGE application

Multifluid equations for MHD

J. G. Lyon, V. G. Merkin, K. A. Sorathia, and M. J. Wiltberger describe a multifluid approach to observing ionized atoms in near-Earth space showing how changes in the magnetic field direction can act to accelerate ions along the field, and modeling how plasma waves behave in such a multifluid environment. They present results of a super-computer simulation of the near-Earth space, modeling the behavior of different plasma fluids and their interactions during a geomagnetic storm.

comparison between AI-enhanced images and high-quality reference data

A deep learning framework for instrument-to-instrument translation of solar observation data

R. Jarolim, A. M. Veronig, W. Pötzi, and T. Podladchikova recently developed a new deep learning framework for Instrument-To-Instrument translation of solar observation data, enabling homogenized data series across multi-instrument datasets. The study demonstrates that the available data sets can directly profit from instrumental improvements, by applying the method to four different applications of ground- and space-based solar observations. 

sample of 650 PhD theses used in the study

Changing methodologies in solar physics

Philip Judge:  For the first time, the methods in solar physics are reviewed using statistical methods. This study attempts to establish a basis for understanding how methods used in research in solar physics have evolved since WWII.