J/A+A/600/A85ivo://CDS.VizieR/J/A+A/600/A85doi:10.26093/cds/vizier.36000085CDSSi R.Li S.Wang K.Guo X.L.Chen Z.B.Yan J.Chen C.Y.Brage T.,Zou Y.M.2017-04-11T12:23:05Z2017-04-05T07:38:14ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.fratomic-physicsSpectral lines of He-like ions are among the most prominent features in X-ray spectra from a large variety of astrophysical and high-temperature fusion plasmas. A reliable plasma modeling and interpretation of the spectra require a large amount of accurate atomic data related to various physical processes. In this paper, we focus on the electron-impact excitation (EIE) process. We adopted the independent process and isolated resonances approximation using distorted waves (IPIRDW). Resonant stabilizing transitions and decays to lower-lying autoionizing levels from the resonances are included as radiative damping. To verify the applicability of the IPIRDW approximation, an independent Dirac R-matrix calculation was also performed. The two sets of results show excellent agreement. We report electron impact excitation collision strengths for transitions among the lowest 49 levels of the 1snl(n<=5,l<=(n-1)) configurations in He-like ions with 20<=Z<=42. The line ratios R and G are calculated for Fe XXV and Kr XXXV.2017A&A...600A..85Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/600/A85CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/A+A/592/A135 : SiXIII and SXV collision strengths (Fernandez-Menchero+, 2016)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/600/A85https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/600/A85http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/600/A85https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/600/A85https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/600/A85http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/600/A85GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapdefaultJ/A+A/600/A85/table1Effective collision strengthsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintZAtomic numbermeta.id;meta.mainintiLower level indexmeta.code;spect.index;phys.atmol.levelintLeveliLower level identification, n ^S^L_J_ == 1snl ^S^L_J_meta.id;phys.atmol.leveljUpper level indexmeta.code;spect.index;phys.atmol.levelintLeveljUpper level identification, n ^S^L_J_ == 1snl ^S^L_J_meta.id;phys.atmol.levelDeltaETransition energy differenceeVphys.energy;phys.atmol.transitiondoubleAji? Sum of E1, M1, E2, and M2 transition rates for transition i-js**-1phys.atmol.transProb;phys.atmol.transitiondoublenullableECS1kEffective collision strengths for transition i-j at electron temperature of (Z-1)^2^*10^3^Kphys.atmol.collStrengthdoubleECS2kEffective collision strengths for transition i-j at electron temperature of (Z-1)^2^*2*10^3^Kphys.atmol.collStrengthdoubleECS5kEffective collision strengths for transition i-j at electron temperature of (Z-1)^2^*5*10^3^Kphys.atmol.collStrengthdoubleECS10kEffective collision strengths for transition i-j at electron temperature of (Z-1)^2^*10^4^Kphys.atmol.collStrengthdoubleECS20kEffective collision strengths for transition i-j at electron temperature of (Z-1)^2^*2*10^4^Kphys.atmol.collStrengthdoubleECS50kEffective collision strengths for transition i-j at electron temperature of (Z-1)^2^*5*10^4^Kphys.atmol.collStrengthdoubleECS100kEffective collision strengths for transition i-j at electron temperature of (Z-1)^2^*10^5^Kphys.atmol.collStrengthdoubleECS200kEffective collision strengths for transition i-j at electron temperature of (Z-1)^2^*2*10^5^Kphys.atmol.collStrengthdoubleECS500kEffective collision strengths for transition i-j at electron temperature of (Z-1)^2^*5*10^5^Kphys.atmol.collStrengthdoubleECS1000kEffective collision strengths for transition i-j at electron temperature of (Z-1)^2^*10^6^Kphys.atmol.collStrengthdoubleECS2000kEffective collision strengths for transition i-j at electron temperature of (Z-1)^2^*2*10^6^Kphys.atmol.collStrengthdouble