The intermediate age open cluster NGC 7044

We present the photometric analysis for the open cluster NGC 7044, based on Johnson-Cousins UBVR CCD observations of 896 stars in a region of 4′20″×2′40″ in the cluster field. Reddening and metallicity are estimated by means of the location of selected samples of members in the (U-B) vs (B-V) diagram, with respect to the lines of the Hyades ZAMS and giants. This selection is performed by considering the location of the representative points in both the V vs (B-V) and V vs (U-B) diagrams simultaneously. The final estimates are found to be very dependent on whether, and to what extent, reddening slopes and absorption coefficients are considered to vary with spectral type. Global considerations, based on the photometric information together with the results of the comparison with theoretical model isochrones, lead to the following set of values: E(B-V)=0.57, [Fe/H]=0.0, (m-M)0= 12.4, and log age(y)=9.4. We discuss to some extent the influence that varying absorption coefficients, published in the literature, would have on these estimates. Our color-magnitude (CM) diagram is compared with selected sets of isochrones, based on evolutionary models computed with and without considering convective overshooting from the stellar core during the phases of H and He core burning. Better general agreement is found when using the overshooting models, between predicted and observed features of the CM diagram, particularly in what concerns the properties of the so-called Red Giant Clump (RGC). With the adopted solution, NGC 7044 turns out to be one of the oldest intermediate-age clusters, very close to, or even beyond the limiting age separating the regimes of He flash and quiet onset of He burning in the red giant phase. The location of the RGC in absolute magnitude, together with the resulting (B-V)0 at the turnoff, leads us to suggest that the efficiency of convective core overshooting in stars of masses around and below 1.5 script M sign⊙ should be slightly higher than that of the models used. An analysis of the spatial distribution of the stars suggest that a mass segregation mechanism is acting in the cluster, in the sense that the most massive members are concentrated in the center. Luminosity and mass functions have been computed; a classical power law fitted to the latter results in a slope of x=-1.66±0.06.