The Height Structure of the Solar Atmosphere from the EUV Perspective

Details The Height Structure of the Solar Atmosphere from the EUV Perspective The Height Structure of the Solar Atmosphere from the EUV Perspective

1998-07-16

arxiv.org/abs/astro-ph/9807175v1

Astronomy and Astrophysics

Astrophysics

6 pages, 2 figures

Scientific paper

10.1086/311587

We investigate the structure of the solar chromosphere and transition region using full Sun images obtained with the Extreme Ultraviolet Imaging Telescope (EIT) aboard the Solar and Heliospheric Observatory (SOHO) spacecraft. The limb seen in the EIT coronal images (taken in lines of Fe IX/X at 171 \AA, Fe XII at 195 \AA and Fe XV at 284 \AA) is an absorption limb predicted by models to occur at the top of the chromosphere where the density of neutral hydrogen becomes significant ($\sim10^{10}$ cm$^{-3}$). The transition-region limb seen in He II 304 \AA images is an emission limb. We find: (1) the limb is higher at the poles than at the equator both in the coronal images (by 1300 $\pm$ 650 km) and the 304 \AA images (by 3500 $\pm$ 120 0 km); and (2) the 304 \AA limb is significantly higher than the limb in the coronal images. The height difference is 3100 $\pm$ 1200 km at the equator, and 6600 $\pm$ 1200 km at the poles. We suggest that the elevation of the 304 \AA limb above the limb in the coronal images may be due to the upper surface of the chromosphere being bumpy, possibly because of the presence of spicules. The polar extension is consistent with a reduced heat input to the chromosphere in the polar coronal holes compared with the quiet--Sun atmosphere at the equator.

Affiliated with

Also associated with

No associations

Rating

The Height Structure of the Solar Atmosphere from the EUV Perspective does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with The Height Structure of the Solar Atmosphere from the EUV Perspective, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Height Structure of the Solar Atmosphere from the EUV Perspective will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-83264