TY - JOUR

T1 - Recombination of W18+ ions with electrons

T2 - absolute rate coefficients from a storage-ring experiment and from theoretical calculations

AU - Spruck, K.

AU - Badnell, N. R.

AU - Krantz, C.

AU - Novotný, O.

AU - Becker, A.

AU - Bernhardt, D.

AU - Grieser, M.

AU - Hahn, M.

AU - Repnow, R.

AU - Savin, D. W.

AU - Wolf, A.

AU - Müller, A.

AU - Schippers, S.

PY - 2014/9/25

Y1 - 2014/9/25

N2 - We present experimentally measured and theoretically calculated rate coefficients for the electron-ion recombination of W18+([Kr]4d104f10) forming W17+. At low electron-ion collision energies, the merged-beam rate coefficient is dominated by strong, mutually overlapping recombination resonances. In the temperature range where the fractional abundance of W18+ is expected to peak in a fusion plasma, the experimentally derived Maxwellian recombination rate coefficient is 5 to 10 times larger than that which is currently recommended for plasma modeling. The complexity of the atomic structure of the open-4f system under study makes the theoretical calculations extremely demanding. Nevertheless, the results of the present Breit-Wigner partitioned dielectronic recombination calculations agree reasonably well with the experimental findings. This also gives confidence in the ability of the theory to generate sufficiently accurate atomic data for the plasma modeling of other complex ions.

AB - We present experimentally measured and theoretically calculated rate coefficients for the electron-ion recombination of W18+([Kr]4d104f10) forming W17+. At low electron-ion collision energies, the merged-beam rate coefficient is dominated by strong, mutually overlapping recombination resonances. In the temperature range where the fractional abundance of W18+ is expected to peak in a fusion plasma, the experimentally derived Maxwellian recombination rate coefficient is 5 to 10 times larger than that which is currently recommended for plasma modeling. The complexity of the atomic structure of the open-4f system under study makes the theoretical calculations extremely demanding. Nevertheless, the results of the present Breit-Wigner partitioned dielectronic recombination calculations agree reasonably well with the experimental findings. This also gives confidence in the ability of the theory to generate sufficiently accurate atomic data for the plasma modeling of other complex ions.

KW - rate coefficients

KW - W18+ ions

KW - theoretical calculations

KW - Maxwellian recombination rate

UR - http://www.scopus.com/inward/record.url?scp=84907908434&partnerID=8YFLogxK

U2 - 10.1103/PhysRevA.90.032715

DO - 10.1103/PhysRevA.90.032715

M3 - Article

AN - SCOPUS:84907908434

VL - 90

JO - Physical Review A - Atomic, Molecular, and Optical Physics

JF - Physical Review A - Atomic, Molecular, and Optical Physics

SN - 1050-2947

IS - 3

M1 - 032715

ER -