D. Gilles, S. Turck-Chièze, M. Busquet, F. Thais, G. Loisel, L. Piau, J. E. Ducret, T. Blenski, C. Blancard, P. Cossé, G. Faussurier, F. Gilleron, J. C. Pain, Q. Porcherot, J. A. Guzik, D. P. Kilcrease, N. H. Magee, J. Harris, S. Bastiani-Ceccotti, F. Delahaye, C. J. Zeippen
Seismology of stars is strongly developing. To address this question we have
formed an international collaboration OPAC to perform specific experimental
measurements, compare opacity calculations and improve the opacity calculations
in the stellar codes [1]. We consider the following opacity codes: SCO,
CASSANDRA, STA, OPAS, LEDCOP, OP, SCO-RCG. Their comparison has shown large
differences for Fe and Ni in equivalent conditions of envelopes of type II
supernova precursors, temperatures between 15 and 40 eV and densities of a few
mg/cm3 [2, 3, 4]. LEDCOP, OPAS, SCO-RCG structure codes and STA give similar
results and differ from OP ones for the lower temperatures and for spectral
interval values [3]. In this work we discuss the role of Configuration
Interaction (CI) and the influence of the number of used configurations. We
present and include in the opacity code comparisons new HULLAC-v9 calculations
[5, 6] that include full CI. To illustrate the importance of this effect we
compare different CI approximations (modes) available in HULLAC-v9 [7]. These
results are compared to previous predictions and to experimental data.
Differences with OP results are discussed.
View original:
http://arxiv.org/abs/1201.4692
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