The population structure of the Large Magellanic Cloud. II. Count-brightness ratios for the central regions.
A combination of luminosity functions and surface photometry, the count-brightness ratio, make it possible to test assumptions on the stellar population content of the crowded central regions of the LMC where deep C-M diagrams are extremely difficult to construct. By comparison with the van Rhijn function it is found that the LMC central disk is not a scaled version of the galactic disk. If the underlying sheet of red giants which is so strongly concentrated toward the bar is assumed to be made of Population II stars in Baade's sense, then most of the light is accounted for and a model emerges containing only very old and very young stars. Because this is unlikely in the LMC, we conclude that the initial assumption has to be dropped and that intermediate-age stars must contribute to the bright resolved giant branch in agreement with known results on peripheral regions.