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The evolutionary stage of the delta Scuti star 44 Tau has been unclear.Recent asteroseismic studies have claimed models on the main sequence, as wellas in the expansion phase of the post-main sequence evolution. However, thesemodels could not reproduce all of the observed frequencies, the modeinstability range, and the fundamental stellar parameters simultaneously. Arecent photometric study has increased the number of detected independent modesin 44 Tau to 15, and a newly found gravity mode at 5.30 c/d extends theobserved frequency range.  Aims. One of the possible evolutionary stages of 44 Tau has not yet beenconsidered: the overall contraction phase after the main sequence. We computedasteroseismic models to examine whether models in this evolutionary stageprovide a better fit of the observed frequency spectrum.  Methods. We used Dziembowski's pulsation code to compute nonadiabaticfrequencies of radial and nonradial modes. Observation of two radial modes andan avoided crossing of dipole modes put strong constraints on the models. Atwo-parametric overshooting routine is utilized to determine the efficiency ofelement mixing in the overshoot layer above the convective core.  Results. We find that pulsation models in the post-MS contraction phasesuccessfully reproduce the observed frequency range, as well as the frequencyvalues of all individual radial and nonradial modes. The theoreticalfrequencies of the mixed modes at 7.79 c/d and 9.58 c/d are in better agreementwith the observations if efficient element mixing in a small overshoot layer isassumed.

A delta Scuti star in the post-MS contraction phase: 44 Tauri