L O,1,2, and 3 Pulsation Constants for Evolutionary Models of Delta-Scuti Stars

Evolutionary sequences at M/M<SUB>sun</SUB> = 1.5, 2.0, and 2.5 were calculated with a version of the Eggleton stellar evolution code for an initial composition X = 0.70, Z = 0.02. From these sequences 14 models spanning the lower part of the Cepheid instability strip were selected for pulsation calculations. All the linear adiabatic m-degenerate eigenvalues with l ≤ 3 for pulsation constants Q[= P(&lt;ρ&gt;/&lt;ρ<SUB>sun</SUB>&gt;)<SUP>1/2</SUP>] in the range 0<SUP>d</SUP>.0096 ≤ Q ≤ 0<SUP>d</SUP>.067 were obtained with a modified version of Dziembowski's second pulsation code, and our code uses a variant of the Cowling approximation for the nonradial modes. Four hundred and eighty-nine Q-values for 35 modes of types F-7H and g<SUB>2</SUB>-p<SUB>7</SUB> are presented. interpolation formulae are provided which predict the model masses, radii, and luminosities from the model periods and temperatures, with worst case errors of 4.4, 2A, and 1.2% in M, L, and R, respectively, when using any of the radial mode or some of the nonradial f- and p-mode results. These formulae were applied to a selection of eight `5 Scuti and three Al Velorum type variables to yield masses and luminosities in the ranges 1.68 ≤ M/M<SUB>sun</SUB> ≤ 2.56 and 15.4 ≤ L/L<SUB>sun</SUB> ≤ 78.0, respectively. If our pulsation constants are relevant, then the primary uncertainties in these results follow from the uncertainties in the effective temperatures for these stars, which are here discussed.

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