Volume 384, Number 1, MarchII 2002
|Page(s)||303 - 316|
|Section||Planets and planetary systems|
|Published online||15 March 2002|
An erupting macrospicule
Characteristics derived from SOHO-CDS spectroscopic observations
Centre for Astrophysics, University of Central Lancashire, Preston PR1 2HE, UK
Corresponding author: S. Parenti, firstname.lastname@example.org
Accepted: 20 December 2001
We report results from the analysis of a sequence of SOHO/CDS observations obtained off-limb in the south polar coronal hole on 6 March 1998. Three successive data sets were obtained with the Normal Incidence Spectrometer (NIS), the first of which showed a jet-like feature visible in the chromospheric and low transition region lines. The morphological characteristics of this feature suggested it was a macrospicule. The two remaining observations of the same region indicated a quiet coronal hole with a density of 108 cm-3 and a temperature rising from K near the limb to K at about km above the limb. These data were averaged and used as “background” for the macrospicule observation. The resulting subtracted spectra showed more details of the feature. In particular, a cloud of plasma was detected at about km above the limb. The macrospicule was found to have a density of the order of 1010 cm-3 and a temperature of about K. The initial outflow velocity near the limb was over 80 km s-1. This decreased to a terminal value of 26 km s-1 above about km.
Key words: Sun: corona / Sun: activity
© ESO, 2002
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.