[Loops] Paper: Periodic spectral line asymmetries in solar coronal structures from slow magnetoacoustic waves

[Erwin Verwichte]

Dear all,

You may be interested in our paper, which has just been accepted for publication in ApJL and which adds to the current debate on periodic flows and waves.

Periodic spectral line asymmetries in solar coronal structures from slow magnetoacoustic waves
Verwichte, E., Marsh, M., Foullon, C., Van Doorsselaere, T., De Moortel, I., Hood, A.W. and Nakariakov, V.M. 

Abstract: Recent spectral observations of upward moving quasi-periodic intensity perturbations in solar coronal structures have shown evidence of periodic line asymmetries near their footpoints. These observations challenge the established interpretation of the intensity perturbations in terms of propagating slow magnetoacoustic waves. We show that slow waves inherently have a bias towards enhancement of emission in the blue wing of the emission line due to in-phase behaviour of velocity and density perturbations. We demonstrate that slow waves cause line asymmetries when the emission line is averaged over an oscillation period or when a quasi-static plasma component in the line-of-sight is included. Therefore, we conclude that slow magnetoacoustic waves remain a valid explanation for the observed quasi-periodic intensity perturbations.

http://go.warwick.ac.uk/erwin_verwichte/publications/verwichte_apjl2010.pdf

Best regards,

Erwin




Dr Erwin Verwichte
Centre for Fusion, Space and Astrophysics
Department of Physics
University of Warwick
Coventry CV4 7AL, United Kingdom
Office PS1.09
tel: +44(0)2476524917
fax: +44(0)2476524887
http://www.warwick.ac.uk/go/erwin_verwichte








-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mithra.physics.montana.edu/pipermail/loops/attachments/20100919/30006315/attachment.html>