Physics and Astronomy/Thayer Plasma Seminar - David Kenward, UNH

Dartmouth Events

Physics and Astronomy/Thayer Plasma Seminar - David Kenward, UNH

Title: "Observations of Ion Upwelling and 630~nm Emission Surge During Pulsating Aurora"

Tuesday, October 15, 2019
4:00pm-5:00pm
Wilder 202
Intended Audience(s): Public
Categories: Lectures & Seminars

Abstract: Data from filtered All Sky Imagers (557.7, 630.0 nm) located at Poker Flat
are presented alongside four hours of Poker Flat Incoherent Scatter Radar
(PFISR) data which shows ion upwelling signatures in the vicinity of
pulsating aurora.  Pulsating aurora observations are more often reported in
557.7 nm and 427.8 nm, as these emissions are more sensitive to high energy
(10s of keV) electron precipitation.  However, data are presented here which
show an abrupt incrase in the 630.0 nm emission intensity along with
pulsations.  This emission is generated preferentially by soft (100s of eV
scale) precipitation.  The source of these soft electrons is unknown, but
may be due to secondary electrons which scatter during a pulsating aurora
event.  We present all sky camera observations which suggest regions of
enhanced soft electron precipitation which tracks the edge of the pulsating
aurora in conjunction with enhanced ambipolar fields, a known factor
contributing to ion upwelling.

 

For more information, contact:
Tressena Manning
603-646-2854

Events are free and open to the public unless otherwise noted.