Helioseismic tests of the new Los Alamos LEDCOP opacities

We compare the helioseismic properties of two solar models, one calibrated with the OPAL opacities and the other with the recent Los Alamos LEDCOP (Li ght Element Detailed Configuration Opacity) opacities. We show that, in the radiative interior of the Sun, the small differences between the two sets of opacities (up to 6% near the base of the convection zone) lead to notice able differences in the solar structure (up to 0.3% in sound speed), with t he OPAL model being the closest to the helioseismic data. More than half of the difference between the two opacity sets results from the interpolation scheme and from the relatively widely spaced temperature grids used in the tables. The remaining 3% intrinsic difference between the OPAL and the LED COP opacities in the radiative interior of the Sun is well within the error bars on the opacity calculations resulting from the uncertainties on the p hysics. We conclude that both the OPAL and LEDCOP opacities produce solar m odels in close agreement with helioseismic inferences, but discrepancies st ill persist at the level of 0.6% between the calculated and inferred sound speed in the radiative interior of the Sun.