Astrophysical properties of star fields in the Large Magellanic Cloud

A.E. PIATTI

Bol. Asoc. Arg. Astron.

AAA Editorial board

Año: 2012 vol. 55 p. 329 - 332

0571?3285

              We present CCD Washington CT1 photometry for the un-precedented database of some 5.5 million of stars distributed throughoutthe entire Large Magellanic Cloud (LMC) main body. The quality andperformance of the data were rigurously examined from extensive com-pleteness artificial star tests over the whole mosaic image data set, sothat field colour-magnitude diagrams (CMDs) were accurately pro-duced. From the star field CMD Hess diagrams, we identified the peaksat the main-sequence turnoff and red clump locations to date themost dominant sub-population (or ?representative? population) in thestellar population mix, while their metallicities were estimated from theCMD location of the most populous red giant branch track. The dis-persion associated with the mean ages and metallicities result in gen-eral a satisfactory estimate of the age/metallicity spread, although somefew individual representative subfields have slightly larger age/metallicityspread. As far as we are aware, these larger age spread do not affect thesubsequent analysis. A detailed version of this work can be seenin Piatti et al. (2012, AJ, 144, 100).