Benchmarking atomic data for astrophysics: Fe XVII EUV lines

¹ DAMTP, Centre for Mathematical Sciences, Wilberforce road, Cambridge, CB3 0WA, UK e-mail: GDelZanna@spd.aas.org
² Department of Chemistry, University of Puerto Rico, PO Box 23346, San Juan, PR 00931-3346, USA

Received: 26 January 2009
Accepted: 1 October 2009

Abstract

In the light of accurate structure and scattering calculations for , we review the status of identifications in the EUV spectrum of this ion using various experimental data, from the X-rays to the UV. Most previous identifications are confirmed, although a critical revision leads to changes in many wavelength values, in particular for the 2p⁵ 3s–2p⁵ 3p and 2p⁵ 3p–2p⁵ 3d transitions, which we observed with the Hinode EUV Imaging Spectrometer (EIS). Several lines are identified here for the first time. We find good agreement between expected and measured line intensities, with a few notable exceptions. In particular, the strong line in the EIS spectra, observed at 254.88 Å, has a consistently low observed intensity. We present two Hinode/EIS observations and discuss which lines are clearly blended in these datasets, and which are reliable for diagnostic purposes.