A.A." Vasilyev

I. "Murakami

T. Kato

U.I. Safronova

National Institute for Fusion Science (NIFS-Repository)

§4. Dielectronic Recombination Rate Coefficients to Excited States of Boronlike Oxygen and Dielectronic Satellite Lines Murakami, I., Kato, T. Safronova, U.I. (Univ. of Nevada, Reno, USA), Vasilyev, A.A. (Science Syst. App!., Inc. USA) Energy levels, radiative transition probabilities, and autoionization rates for B-like oxygen (03+) including Is'2s'nl, Is'2s2pnl, and 1s'2p'nl (n=2-8, l:5n-l) states were calculated by multi-configurational Hartree-Fock method (Cowan code) and relativistic many-body perturbation theory method (RMBPT code). Autoionizing levels above three thresholds (ls'2s' IS, Is'2s2p 3p, Is'2s2p Ip) were considered. Configuration mixing (2s'nl + 2p'nl) plays an important role for all atomic characteristics. Branching ratios relative to the first threshold and intensity factor were calculated for satellites lines and dielectronic recombination rate coefficients for the excited 105 odd-parity and 94 even-parity states. The dielectronic recombination rate coefficients were calculated including Is'2s'nl, Is'2s2pnl, and Is'2p'nl (n=2-8, l:5n-l) states. The contribution from the excited states higher than n=8 was estimated by extrapolation of all atomic characteristics to derive the total dielectronic recombination rate coefficient. The orbital angular momentum quantum number I distribution of the rate coefficients shows a peak at 1=5. The total dielectronic recombination rate coefficient was derived as a function of electron temperature. The dielectronic satellite lines were also obtained. The state selective dielectronic recombination rate coefficients to excited states of B-like oxygen were obtained, which are useful for modeling 0 IV spectral lines in a recombining plasma. Dielectronic recombination (DR) to the excited states fr 0 3+ 0 4+' . om to IS defined by the followmg sequence of processes: 04+(2s')+e->03+(2s2pn/+2p'nl) -> 04+(2s' +2s2p)+e ->03\2s'n/+2s2p3/+2s2p'+2p3) + hv As an initial state we consider the ground state of 0 4+, 2s'. The 2s2pnl and 2p'nl states are taken into account as doubly excited intermediate states. The DR rate coefficients <X.i(y'lao), to the excited state are obtained by summing up the intensity factor Qiy,y'lao) multiplied the exponential factor over the autoionization levels yas follows, a.(rlao)=3.3XI0-24 IH Ie-T'QAY,rlao)/g(ao) ( J312 '-'-T, r where Qd(Y, Y'IIXQ)= gyAr(Y, y')K(y,lXQ) K(y,ao) = A.(y,ao) (A,(y)+A.(y)), A,(y) = IA,(y,r'),A.(y) = IA.(y,a') y" a' Here Aly,y') are radiative transition probabilities and A,(y,ao) are autoionization rates. The total DR rate coefficients are obtained by summation of the rate coefficients of DR processes through all possible intermediate singly and doubly excited states: For total DR rate coefficients we need to consider contribution from doubly excited states with high n levels s and also the contribution from single excited states with high n, 28201 states. Tabulated data atolald =o.f.I d +cxb d +a cd are given in Table 1. Table 1. Total DR rate coefficients (a""ld in cm3/s): 101a\ _8+b , fu' f a d -(l dad +a d as nchon 0 electron temperature (T, in eV) for B-like oxygen. Contributions of a'd and a'd are sum from excited states with n=2-8 and n=9-30000 respectively. Contribution of abd is from scaling of th~ 2s'nl-2s2pnl transitions from n=9 up to n = 30000. T, 0.1000 0.1300 0.1690 0.2197 0.2856 0.3713 0.4827 0.6275 0.8157 1.0604 1.3786 1.7922 2.3298 3.0287 3.9374 5.1186 6.6542 8.6504 11.2455 14.6192 19.0049 24.7064 32.1184 41.7539 54.2800 70.5640 91.7332 3.06[-11] 1.00[-83] 0.00[00] 3.06[-11] 3.63[-11] 8.00[-67] 0.00[00] 3.63[-11] 4.16[-11] 6.90[-54] 0.00[00] 4.16[-11] 4.61[-11] 3.00[-28] 1.00[-24] 4.61[-.11] 4.98[-11] 1.10[-24] 7.00[-22] 4.98[-11] 5.28[-11] 3.52[-22] 1.90[-19] 5.28[-11] 5.48[-11] 3.\0[-20] 1.52[-17] 5.48[-11] 5.53[-11] 1.10[-18] 4.25[-16] 5.53[-11] 5.44[-11] 1.89[-17] 5.25[-15] 5.44[-11] 5.24[-11] 2.34[-16] 3.45[-14] 5.25[-11] 4.97[-11] 3.87[-15] 1.38[-13] 4.98[-11] 4.63[-11] 5.28[-14] 3.73[-13] 4.67[-11] 4.23[-11] 4.05[-13] 7.42[-13] 4.34[-11] 3.75[-11] 1.82[-12]1.16[-12] 4.05[-11] 3.24[-11] 5.29[-12] 1.51[-12] 3.92[-11] 2.73[-11] 1.10[-1\] 1.70[-12] 4.00[-11] 2.23[-11] 1.78[-11] 1.71[-12] 4.18[-11] 1.78[-11] 2.34[-11] 1.57[-12] 4.27[-11] 1.38[-11] 2.64[-1\] 1.35[-12] 4.16[-11] 1.04[-11] 2.65[-11] 1.10[-12] 3.80[-11] 7.75[-12] 2.43[-11] 8.62[-13] 3.29[-11] 5.65[-12] 2.07[-11] 6.52[-13] 2.70[-11] 4.05[-12] 1.67[-11] 4.81[-13] 2.12[-11] 2.87[-12] 1.30[-11] 3.47[-13] 1.62[-11] 2.01[-12] 9.73[-12] 2.47[-13] 1.20[-11] 1.40[-12] 7.12[-12] 1.74[-13] 8.70[-12] 9.65[-13] 5.12[-12] 1.21[-13] 6.21[-12] We take into account doubly excited states 2s2pnl and 2p'nl (n;o,8, 157) as intermediate resonance states with n up to 30000 to calculate the DR rate coefficients. Most of state selective DR rate coefficients show double peaks as a func-tion of electron temperature. The transitions through inter-mediate states 2s2pnl make a peak in the rate coefficients at T,,= 2-10 eV. Configuration mixing [2s'nl + 2p'nl] plays an important role for the DR rate coefficients of 2s'nl levels with 0:58 at low temperature. The state selective rate coefficients can be used in a collisional-radiative model for investigating popUlation kinetics and plasma diagnostics for recombining plasma. 409 

Dielectronic Recombination Rate Coefficients to Excited States of Boronlike Oxygen and Dielectronic Satellite Lines

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