Research Highlights
Research Highlights
A selection of highlights culled from publications by HAO staff.

EUV polarimetric diagnostics of the solar corona: the Hanle effect of Ne viii 770 A
Raveena Khan, Sarah Gibson, Roberto Casini, and K. Nagaraju utilize 3D 'Magneto-hydrodynamic Algorithm outside a Sphere' (MAS) models as input to the FORWARD code to model polarization in Ne viii line produced due to resonance scattering, and interpret its modification due to collisions and the magnetic fields through the Hanle effect.

On the intermittency of hot plasma loops in the solar corona
P. Judge and N.P.M. Kuin ask why and how are entire hydromagnetic structures only intermittently loaded with bright coronal plasma in the Sun? Their findings consolidate the claim that unobserved physical processes are at work which govern the heating of long-lived coronal loops.

Magnetohydrodynamic turbulence simulations as a testing ground for PUNCH
Sarah Gibson et. al. present a numerical study that combines magnetohydrodynamic simulations of turbulence together with forward-modeling synthesis of white- light data via the FORWARD code. Their study is a first step in the process of analyzing and understanding the unprecedented information that The Polarimeter to UNify the Corona and Heliosphere (PUNCH) will provide.

Erratum: Analysis of Seeing-Induced Polarization Cross-Talk and Modulation Scheme Performance
R. Casini, A. G. de Wijn, P. G. Judge analyze (Published 2012 September 4) the generation of polarization cross-talk in Stokes polarimeters by atmospheric seeing, and its effects on the noise statistics of spectropolarimetric measurements for both single-beam and dual-beam instruments.

Interactions between MSTIDs and Ionospheric Irregularities in the Equatorial Region Observed on May 13-14, 2013
Kun Wu, and Liying Qian investigate the interactions between medium-scale traveling ionospheric disturbances (MSTIDs) and the equatorial ionization anomaly (EIA), and between MSTIDs and equatorial plasma bubbles (EPBs) on the night of May 13-14, 2013, based on observations from multiple instruments (all-sky imager, digisonde, and global positioning system (GPS)).

A unifying polarization formalism for electric- and magnetic-multipole interactions
R. Casini, R. Manso Sainz, A. Lopez Ariste, and N. Kaikati extend the spherical tensorial formalism for polarization to the treatment of eletric- and magnetic-multipole transitions of any order, to model the radiation anisotropy affecting the scattering of radiation in an electric-quadrupole transition, and the associated Hanle effect in the presence of a magnetic field.

A Community Ionosphere-Thermosphere Observing System Simulation Experiment (OSSE) Tool
Chih-Ting Hsu, et al. in this study demonstrate the utility of DART/TIEGCM as an IT OSSE tool, using synthetic observations simulated using a currently planned NASA Geospace Dynamics Constellation (GDC) observing system design. Five sets of OSSEs are carried out to compare the effects of assimilating various combinations of prospective GDC observations (e.g., neutral temperature, neutral wind, neutral composition, atomic oxygen ion density, and ion and electron temperature) during a major geomagnetic storm period of the St Patrick's Day Storm on March 17, 2013.

MAGE Model Simulation of the Pre-reversal Enhancement and Comparison with ICON and Jicamarca ISR Observations
Qian Wu, Wenbin Wang, Dong Lin, Liying Qian, Chaosong Huang, and Yongliang Zhang use the latest coupled geospace model MAGE (Multiscale Atmosphere-Geospace Environment) and observations from Jicamarca ISR and ICON IVM instrument, we examine the pre-reversal enhancement during geomagnetic quiet time period.

HIWIND Balloon and Antarctica Jang Bogo FPI High Latitude Conjugate Thermospheric Wind Observations and Simulations
Qian Wu, Dong Lin, Wenbing Wang, Liying Qian, Geonhwa Jee, Changsup Lee, and Jeong-han Kim use balloon instrument in the northern hemisphere and ground based instrument in the southern hemisphere to study the conjugacy of the thermospheric winds of high latitudes.