A Doppler Dimming Determination of Coronal Outflow Velocity
Abstract
Outflow velocities in a polar coronal hole are derived from observations made during a 1982 sounding rocket flight. The velocity results are derived from a Doppler dimming analysis of resonantly scattered H I Ly-alpha. This analysis indicates radial outflow velocities of 217 km/s at 2 solar radii from sun-center with an uncertainty range of 153 to 251 km/s at a confidence level of 67 percent. These results are best characterized as strong evidence for supersonic outflow within 2 solar radii of sun-center in a polar coronal hole. Several means for obtaining improved accuracy in future observations are discussed.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- July 1993
- DOI:
- 10.1086/172930
- Bibcode:
- 1993ApJ...412..410S
- Keywords:
-
- Coronal Holes;
- Dimming;
- Doppler Effect;
- Sounding Rockets;
- Astronomical Models;
- Chromosphere;
- Coronagraphs;
- Flow Velocity;
- Lyman Alpha Radiation;
- Particle Emission;
- Radial Velocity;
- Solar Physics;
- SUN: CORONA;
- SUN: SOLAR WIND;
- SUN: PARTICLE EMISSION;
- SUN: UV RADIATION