Cover Image

Multi-wavelength observations of Proxima Centauri

Show other versions (1)

Aims. We report simultaneous observations of the nearby flare star Proxima Centauri with VLT/UVES and XMM-Newton over three nights in March 2009. Our optical and X-ray observations cover the star’s quiescent state, as well as its flaring activity and allow us to probe the stellar atmospheric conditi...

Full description

Saved in:
Bibliographic Details
Main Authors: Fuhrmeister, Birgit (Author) , Lalitha, S. (Author) , Poppenhäger, Katja (Author) , Rudolf, N. (Author) , Liefke, Carolin (Author) , Reiners, A. (Author) , Schmitt, Jürgen (Author) , Ness, J.-U. (Author)
Format: Article (Journal)
Language:English
Published: 20 October 2011
In: Astronomy and astrophysics
Year: 2011, Volume: 534, Pages: 1-17
ISSN:1432-0746
DOI:10.1051/0004-6361/201117447
Online Access:Verlag, lizenzpflichtig, Volltext: https://doi.org/10.1051/0004-6361/201117447
Verlag, lizenzpflichtig, Volltext: https://www.aanda.org/articles/aa/abs/2011/10/aa17447-11/aa17447-11.html
Get full text
Author Notes:B. Fuhrmeister, S. Lalitha, K. Poppenhaeger, N. Rudolf, C. Liefke, A. Reiners, J.H.M.M. Schmitt, and J.-U. Ness
Description
Summary:Aims. We report simultaneous observations of the nearby flare star Proxima Centauri with VLT/UVES and XMM-Newton over three nights in March 2009. Our optical and X-ray observations cover the star’s quiescent state, as well as its flaring activity and allow us to probe the stellar atmospheric conditions from the photosphere into the chromosphere, and then the corona during its different activity stages. Methods. Using the X-ray data, we investigate variations in coronal densities and abundances and infer loop properties for an intermediate-sized flare. The optical data are used to investigate the magnetic field and its possible variability, to construct an emission line list for the chromosphere, and use certain emission lines to construct physical models of Proxima Centauri’s chromosphere. Results. We report the discovery of a weak optical forbidden Fe xiii line at 3388 Å during the more active states of Proxima Centauri. For the intermediate flare, we find two secondary flare events that may originate in neighbouring loops, and discuss the line asymmetries observed during this flare in H i, He i, and Ca ii lines. The high time-resolution in the Hα line highlights strong temporal variations in the observed line asymmetries, which re-appear during a secondary flare event. We also present theoretical modelling with the stellar atmosphere code PHOENIX to construct flaring chromospheric models.
Item Description:Gesehen am 31.05.2023
Physical Description:Online Resource
ISSN:1432-0746
DOI:10.1051/0004-6361/201117447

Similar Items