Updating of ionization data for ionization balance evaluations of atoms and ions for the elements hydrogen to germanium

Mattioli, M.; Mazzitelli, G.; Finkenthal, M.; Mazzotta, P.; Fournier, K. B.; Kaastra, J. S.; Puiatti, M. E.

doi:10.1088/0953-4075/40/18/002

Cited by 31 publications

(35 citation statements)

References 131 publications

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“…A.6. They seem accurate and reliable enough in the entire range of energies needed for our purposes and are consistent with more recent studies (Godunov & Ivanov 1999;Bartlett & Stelbovics 2004;Mattioli et al 2007). The two vertical bars in this figure represent the energy equal to kT e for the temperatures of the core and halo populations at 1 AU from the Sun.…”

Section: A2 Electron Impact Ionization Of Ne He and Osupporting

confidence: 91%

Modulation of neutral interstellar He, Ne, O in the heliosphere. Survival probabilities and abundances at IBEX

Bzowski

Sokół

Kubiak

et al. 2013

A&A

111

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Context. Direct sampling of neutral interstellar (NIS) atoms by the Interstellar Boundary Explorer (IBEX) can potentially provide a complementary method for studying element abundances in the Local Interstellar Cloud (LIC) and processes in the heliosphere interface. Aims. We set the stage for abundance-aimed in-depth analysis of measurements of NIS He, Ne, and O by IBEX and determine systematic differences between abundances derived from various calculation methods and their uncertainties.Methods. Using a model of ionization rates of the NIS species in the heliosphere, based on independent measurements of the solar wind and solar EUV radiation, we developed a time-dependent method of calculating the survival probabilities of NIS atoms from the termination shock (TS) of the solar wind to IBEX. With them, we calculated densities of these species along the Earth's orbit and simulated the fluxes of NIS species as observed by IBEX. We studied pairwise ratios of survival probabilities, densities, and fluxes of NIS species at IBEX to calculate correction factors for inferring the abundances at TS. Results. The analytic method of calculating the survival probabilities gives acceptable results only for He and Ne during low solar activity. For the remaining portions of the solar cycle, and at all times for O, a fully time-dependent model should be used. Electronimpact ionization is surprisingly important for NIS O. Interpreting the IBEX observations using the time-dependent model yields the LIC Ne/O abundance of 0.16 ± 40%. The uncertainty is mostly due to uncertainties in the ionization rates and in the NIS gas flow vector. Conclusions. The Ne/He, O/He, and Ne/O ratios for survival probabilities, local densities, and fluxes scaled to TS systematically differ and thus an analysis based only on survival probabilities or densities is not recommended, except the Ne/O abundance for observations at low solar activity.

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Section: A2 Electron Impact Ionization Of Ne He and Osupporting

confidence: 91%

Modulation of neutral interstellar He, Ne, O in the heliosphere. Survival probabilities and abundances at IBEX

Bzowski

Sokół

Kubiak

et al. 2013

A&A

111

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“…On average, the adopted cross sections reproduce the measured cross sections to an accuracy of 13%. We note that, for example, the ionization rate of Fe iv here refers to the process where an incident electron ionizes the Fe iv ion to produce Fe v. Mattioli et al (2007) have produced an updated set of ionization cross-sections and rate coefficients and find reasonable agreement with the rates of Dere (2007).…”

Section: Ionization Rate Coefficientsmentioning

confidence: 75%

CHIANTI – an atomic database for emission lines

Dere¹,

Landi²,

Young³

et al. 2009

A&A

460

451

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Aims. The goal of the CHIANTI atomic database is to provide a set of atomic data for the interpretation of astrophysical spectra emitted by collisionally dominated, high temperature, optically thin sources. Methods. A complete set of ground level ionization and recombination rate coefficients has been assembled for all atoms and ions of the elements of H through Zn and inserted into the latest version of the CHIANTI database, CHIANTI 6. Ionization rate coefficients are taken from the recent work of Dere (2007, A&A, 466, 771) and recombination rates from a variety of sources in the literature. These new rate coefficients have allowed the calculation of a new set of ionization equilibria and radiative loss rate coefficients.For some ions, such as Fe viii and Fe ix, there are significant differences from previous calculations. In addition, existing atomic parameters have been revised and new atomic parameters inserted into the database. Results. For each ion in the CHIANTI database, elemental abundances, ionization potentials, atomic energy levels, radiative rates, electron and proton collisional rate coefficients, ionization and recombination rate coefficients, and collisional ionization equilibrium populations are provided. In addition, parameters for the calculation of the continuum due to bremsstrahlung, radiative recombination and two-photon decay are provided. A suite of programs written in the Interactive Data Language (IDL) are available to calculate line and continuum emissivities and other properties. All data and programs are freely available at http://wwwsolar.nrl.navy.mil/ chianti

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“…10 the ratio between σ inelastic and the ionization cross sections of C 3+ ions by electrons from Crandall et al [78], σ e , here called the "experimental ratio," as a function of the projectile energy. Also shown are the ratios between the PWBA-based calculations for the antiscreening contribution for the present collision systems from Montenegro and Meyerhof [70], σ anti , and the calculations for the ionization cross sections of C 3+ by electrons according to the fitting function presented by Mattioli et al [79] based on the distorted-wave exchange model [80], here called the "theoretical ratio." The data from Kirchner et al [10] for the Ne target are also included for completeness.…”

Section: B Single Loss Accompanied By Target Multiple Ionizationmentioning

confidence: 99%

“…The lines are the ratios of calculations for the antiscreening contribution from Ref [70]. and the ionization cross sections of C 3+ ions by electron impact[79]: solid green line, He; dashed purple line, Ne; dotted blue line, Ar; dash-dotted red line, Kr; and dash-dot-dotted black line, Xe. The energies of the electron-impact data are those equivalent to the heavy-ion projectiles with the same velocity (see text).…”

mentioning

confidence: 99%

Absolute cross sections for electron loss, electron capture, and multiple ionization in collisions ofC3+with noble gases

et al. 2010

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Absolute charge-state-correlated cross sections for projectile electron loss, electron capture, and target multiple ionization in collisions between C 3+ ions and noble gases have been measured for energies between 1.3 and 3.5 MeV. The data have been compared with other similar absolute cross sections existent in the literature for several projectiles. Calculations for the single-loss−multiple-ionization channel have been performed for the screening mode, using both an extended version of the classical-impulse free-collision model and the plane-wave Born approximation (PWBA), and for the antiscreening mode within the PWBA. The energy dependence of the average number of target active electrons which contribute to the antiscreening has been described by means of a simple function, which is "universal" for noble gases but, in principle, projectile dependent. A method has been developed to obtain the number of active target electrons for each subshell in the high-velocity regime, which presented physically reasonable results. Analyses of the dependences of the single-capture and transfer-ionization (SC and TI, respectively) processes on the projectile charge states showed that, for He, equally charged bare and dressed projectiles have very similar cross sections; the latter thus acting as structureless point charges. A behavior similar to that in the SC has been observed for the pure single ionization of He by projectiles with different charge states and of the other noble gases by singly charged projectiles. It has been shown that the q 2 dependence of the pure-single and total-ionization cross sections, predicted by first-order models, is only valid for high-collision velocities. For slower collisions, the electron capture process becomes more relevant and competes with the ionization channel, a feature which grows in importance as the projectile charge state increases.

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Updating of ionization data for ionization balance evaluations of atoms and ions for the elements hydrogen to germanium

Cited by 31 publications

References 131 publications

Modulation of neutral interstellar He, Ne, O in the heliosphere. Survival probabilities and abundances at IBEX

Modulation of neutral interstellar He, Ne, O in the heliosphere. Survival probabilities and abundances at IBEX

CHIANTI – an atomic database for emission lines

Absolute cross sections for electron loss, electron capture, and multiple ionization in collisions ofC3+with noble gases

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