82 citations · 329 across the 12 of their papers we have counts for
6 papers · 1 filter
Velocity and Density Fluctuations in the Quiet Sun Corona
Michael Hahn, Xiangrong Fu, Stefan J. Hofmeister +3
We investigate the properties and relationship between Doppler-velocity fluctuations and intensity fluctuations in the off-limb quiet Sun corona. These are expected to reflect the…
Revised Point-Spread Functions for the Atmospheric Imaging Assembly onboard the Solar Dynamics Observatory
Stefan Hofmeister, Daniel Wolf Savin, Michael Hahn
We present revised point-spread functions (PSFs) for the Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory (SDO). These PSFs provide a robust estimate of th…
A Simple Method for Modeling Collision Processes in Plasmas with a Kappa Energy Distribution
Michael Hahn, Daniel Wolf Savin
We demonstrate that a nonthermal distribution of particles described by a kappa distribution can be accurately approximated by a weighted sum of Maxwell-Boltzmann distributions. We…
Influence of Electron-Impact Multiple Ionization on Equilibrium and Dynamic Charge State Distributions: A Case Study Using Iron
Michael Hahn, Daniel Wolf Savin
We describe the influence of electron-impact multiple ionization (EIMI) on the ionization balance of collisionally ionized plasmas. We are unaware of any previous ionization balanc…
Evidence for Wave Heating of the Quiet Sun Corona
Michael Hahn, Daniel Wolf Savin
We have measured the energy and dissipation of Alfvenic waves in the quiet Sun. A magnetic field was used to infer the location and orientation of the magnetic field lines along wh…
Measurements of Anisotropic Ion Temperatures, Non-Thermal Velocities, and Doppler Shifts in a Coronal Hole
M. Hahn, D. W. Savin
We present a new diagnostic allowing one to measure the anisotropy of ion temperatures and non-thermal velocities as well as Doppler shifts with respect to the ambient magnetic fie…