Imaging radar observations of Farley Buneman waves during the JOULE II experiment

Vector electric fields and associated <I><B>E</B></I>×<I><B>B</B></I> drifts measured by a sounding rocket in the auroral zone during the NASA JOULE II experiment in January 2007, are compared with coherent scatter spectra measured by a 30 MHz radar imager in a common volume. Radar imaging permits precise collocation of the spectra with the background electric field. The Doppler shifts and spectral widths appear to be governed by the cosine and sine of the convection flow angle, respectively, and also proportional to the presumptive ion acoustic speed. The neutral wind also contributes to the Doppler shifts. These findings are consistent with those from the JOULE I experiment and also with recent numerical simulations of Farley Buneman waves and instabilities carried out by Oppenheim et al. (2008). Simple linear analysis of the waves offers some insights into the spectral moments. A formula relating the spectral width to the flow angle, ion acoustic speed, and other ionospheric parameters is derived

Magnetic aspect sensitivity of high‐latitude E region irregularities measured by the RAX‐2 CubeSat

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106761/1/jgra50801.pd

Radio Aurora Explorer: Mission science and radar system

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95507/1/rds5936.pd

First measurements of radar coherent scatter by the Radio Aurora Explorer CubeSat

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95350/1/grl29342.pd

Enhanced ion acoustic lines due to strong ion cyclotron wave fields

The Fast Auroral Snapshot Explorer (FAST) satellite detected intense and coherent 5–20 m electric field structures in the high-latitude topside auroral ionosphere between the altitudes of 350 km and 650 km. These electric fields appear to belong to electrostatic ion cyclotron (EIC) waves in terms of their frequency and wavelengths. Numerical simulations of the response of an electron plasma to the parallel components of these fields show that the waves are likely to excite a wave-driven parallel ion acoustic (IA) instability, through the creation of a highly non-Maxwellian electron distribution function, which when combined with the (assumed) Maxwellian ion distribution function provides inverse Landau damping. Because the counter-streaming threshold for excitation of EIC waves is well below that for excitation of IA waves (assuming Maxwellian statistics) our results suggest a possible two step mechanism for destabilization of IA waves. Combining this simulation result with the observational fact that these EIC waves share a common phenomenology with the naturally enhanced IA lines (NEIALS) observed by incoherent scatter radars, especially that they both occur near field-aligned currents, leads to the proposition that this two-step mechanism is an alternative path to NEIALS

Executive Functioning in Subtypes of Attention Deficit Hyperactivity Disorder

Introduction: This study aims to evaluate executive functions (EF), such as inhibition, planning, working memory, and set shifting, in children with attention deficit hyperactivity disorder (ADHD) by comparing three ADHD subtype groups (ADHD-Inattentive, ADHD-Combined, and ADHD-Comorbid) and a normal control group