Published by
EDP Sciences
EDP Sciences Journals List
Subscriber Authentication Point
Home All issues Volume 393/ 2 Article
Free access
Issue A&A
Volume 393, Number 2, October II 2002
Page(s) 649 - 659
Section The Sun
DOI http://dx.doi.org/10.1051/0004-6361:20021057



A&A 393, 649-659 (2002)
DOI: 10.1051/0004-6361:20021057

A wavelet analysis of quasi-periodic variability across a solar coronal hole region

M. S. Marsh, R. W. Walsh and B. J. I. Bromage

Centre for Astrophysics, University of Central Lancashire, Preston, PR1 2HE, UK

(Received 3 May 2002 / Accepted 18 July 2002)

Abstract
High time resolution ( $\approx$13 s cadence) Solar and Heliospheric Observatory (SOHO) Coronal Diagnostic Spectrometer (CDS) Grazing Incidence Spectrometer (GIS) time series data is analysed for evidence of quasi-periodic variability in the solar corona. The observations are obtained from a GIS study of a coronal hole boundary region taken in October 1997. A wavelet analysis is applied to EUV emission lines covering a temperature range of $\log T_{\rm e}=$ 5.3-6.1 K. Wavelet analysis allows the frequency and temporal information of any periods present within the data to be analysed. Statistically significant periods are found within the range 100-900 s and 1500 s. Observations of short wavepackets with periods of the order 50-100 s with durations of 2-5 cycles are reported. Observations of a decay in the driving period over time are also described.


Key words: Sun: corona -- Sun: oscillations -- Sun: transition region -- Sun: UV radiation -- waves

Offprint request: M. S. Marsh, mmarsh@uclan.ac.uk




© ESO 2002

What is OpenURL?

The OpenURL standard is a protocol for transmission of metadata describing the resource that you wish to access. An OpenURL link contains article metadata and directs it to the OpenURL server of your choice. The OpenURL server can provide access to the resource and also offer complementary services (specific search engine, export of references...). The OpenURL link can be generated by different means.
  • If your librarian has set up your subscription with an OpenURL resolver, OpenURL links appear automatically on the abstract pages.
  • You can define your own OpenURL resolver with your EDPS Account. In this case your choice will be given priority over that of your library.
  • You can use an add-on for your browser (Firefox or I.E.) to display OpenURL links on a page (see http://www.openly.com/openurlref/). You should disable this module if you wish to use the OpenURL server that you or your library have defined.