HAO Research Highlights

Graph depicting extended solar cycles
December 3, 2018

In 1844 Schwabe discovered that the number of sunspots increased and decreased over a period of about 11 years, that variation became known as the sunspot cycle.

Graph depicting average intensity of magnetic structures as a function of width (a) and equivalent radius (b)
December 3, 2018

Solar irradiance models indicate that irradiance variations are dominated by changes in disk-coverage of magnetic structures, whose brightness is thought to be determined by their size and average magnetic flux density.

Graph showing WACCM-X (2.0) simulated summer temperature profiles of year 1974 and year 2003
December 2, 2018

The nighttime mesopause, marking the boundary of mesosphere and thermosphere and having the coldest atmospheric temperature, is formed mainly by the combination of radiative cooling by CO2, and the adiabatic flow in the Mesosphere and Lower Thermosphere.

(a) The inferred line-of-sight (LOS) magnetic field B_LOS obtained from the forward synthesis of the circular polarization signal from the MHD model data at a time during the quasi-static phase of the flux rope; (b) The same as (a) but only show the pixels of the measured B_LOS with sufficient signal to noise ratio; (c) The axial field strength in the mid cross-section of the flux rope; (d) The 3D field lines of the coronal magnetic field as view
November 13, 2018

From a magnetohydrodynamic (MHD) simulation of the eruption of a prominence hosting coronal flux rope, Yuhong Fan and others carry out forward synthesis of the circular polarization signal (Stokes V signal) of the FeXIII emission line at 1074.7 nm produced by the MHD model.

Pitch angle scattering of electrons in high resolution LFM fields
November 13, 2018

Mary Hudson and others have studied field line curvature scattering by the magnetic field structure associated with Bursty Bulk Flows (BBFs), using simulated output fields from the Lyon‐Fedder‐Mobarry (LFM) global magnetohydrodynamic (MHD) code for specified solar wind input.