EDP Sciences
Free access
Volume 425, Number 3, October III 2004
Page(s) 1083 - 1095
Section The Sun
DOI http://dx.doi.org/10.1051/0004-6361:20041069

A&A 425, 1083-1095 (2004)
DOI: 10.1051/0004-6361:20041069

CDS wide slit time-series of EUV coronal bright points

I. Ugarte-Urra1, J. G. Doyle1, V. M. Nakariakov2 and C. R. Foley3

1  Armagh Observatory, College Hill, Armagh BT61 9DG, N. Ireland
    e-mail: iuu@star.arm.ac.uk
2  Physics Department, University of Warwick, Coventry, CV4 7AL, UK
3  Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking, Surrey RH5 6NT, UK

(Received 9 April 2004 / Accepted 10 June 2004 )

Wide slit ( $90^{\prime\prime}\times240^{\prime\prime}$) movies of four Extreme Ultraviolet coronal bright points (BPs) obtained with the Coronal Diagnostic Spectrometer (CDS) on board the Solar and Heliospheric Observatory (SoHO) have been inspected. The wavelet analysis of the He I 584.34 Å, O V 629.73 Å and Mg VII/IX 368 Å time-series confirms the oscillating nature of the BPs, with periods ranging between 600 and 1100 s. In one case we detect periods as short as 236 s. We suggest that these oscillations are the same as those seen in the chromospheric network and that a fraction of the network bright points are most likely the cool footpoints of the loops comprising coronal bright points. These oscillations are interpreted in terms of global acoustic modes of the closed magnetic structures associated with BPs.

Key words: Sun: oscillations -- Sun: corona -- Sun: transition region -- Sun: chromosphere -- Sun: UV radiation -- Sun: magnetic fields

© ESO 2004