Egidio Landi

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The CHIANTI atomic database contains atomic energy levels, wavelengths, radiative transition probabilities and electron excitation data for a large number of ions of astrophysical interest. Version 4 has been released, and proton excitation data is now included, principally for ground configuration levels that are close in energy. The fitting procedure for(More)
The CHIANTI atomic database contains atomic energy levels, wavelengths, radiative transition probabilities, and electron excitation data for a large number of ions of astrophysical interest. Version 4 has been released, and proton excitation data are now included, principally for ground configuration levels that are close in energy. The fitting procedure(More)
P. R. Young, G. Del Zanna, H. E. Mason, K. P. Dere, E. Landi, M. Landini, G. A. Doschek, 1STFC Rutherford Appleton Laboratory, Chilton, Didcot, Oxfor 2University College London, Department of Space and Climate Physics, 3DAMTP, Centre for Mathematical Sciences, 4George Mason University, 4400 University Dr., Fairfax 5Artep, Inc at Naval Research Laboratory,(More)
Transfusion-associated graft-versus-host disease (TA-GVHD) is a rare and usually fatal syndrome. Clinical manifestations are fever, maculopapular skin rash, nausea, vomiting, diarrhea, hepatitis and pancytopenia owing to bone marrow hypoplasia. It can occur in recipients with severe immunosuppression and in immunocompetent recipients after transfusion of(More)
We study the Differential Emission Measure distribution of two pairs of active and quiet regions of the solar atmosphere, observed by CDS Normal Incidence Spectrometer (NIS) on SOHO, and investigate their temperature and density structure . Use is made of the Arcetri Method (Landi & Landini 1997) for DEM and density diagnostics. An iterative method for(More)
In the present work the element abundances in an active region observed on the solar disk are studied using EUV spectral lines observed by the Coronal Diagnostic Spectrometer (CDS) on board of SOHO. Making use of the large number of lines identified in the CDS spectral range and of the instrument imaging capability, the abundances of several elements having(More)
P. R. Young, G. Del Zanna, H. E. Mason, K. P. Dere, E. Landi, M. Landini, G. A. Doschek, 1STFC Rutherford Appleton Laboratory, Chilton, Didcot, Oxfor 2University College London, Department of Space and Climate Physics, 3DAMTP, Centre for Mathematical Sciences, 4George Mason University, 4400 University Dr., Fairfax 5Artep, Inc at Naval Research Laboratory,(More)
A study is presented of the optical thickness of spectral lines of carbon, nitrogen and oxygen ions in the quiet sun. The observations consist of cross limb scans by the SUMER and CDS spectrometers on the SOHO spacecraft. A maximum likelihood spectral line fitting code has been adapted to analyse the multiplet profiles and to provide an assessment of errors(More)
Amethod is given for performing simultaneous temperature and density diagnostics of an optically thin plasma by means of all the available observations of lines of the same ions. The density and differential emission measure at selected temperatures may be measured and the chemical composition verified. Themethod is applied to line emissionmeasured bySERTS(More)