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tokens: Yonsei-Yale (Spada et al. 2013 ). With the isochrones chosen, it creates synthetic populations that are then contrasted with observations. To populate the synthetic models, Talos uses a Kroupa IMF (Kroupa 2001 ) and takes into account various properties of the input data to make the models directly comparable to the observations. These properties include distance, reddening, binary fraction, photometric errors, and completeness fractions. Then, the combination of synthetic populations that best matches the observed decontaminated CMD and MDF is selected as the SFH of the object. The comparison between synthetic and observed CMDs is done using Hess diagrams, in which each point represents the number of stars at a specific color-magnitude bin. Each time a combination of synthetic populations is created, the routine calculates the differences between the star counts in the model and the observations at each color-magnitude bin, along with the difference at each metallicity bin from the MDF. With these differences, Talos calculates a Poissonian chi-squared, whose minimization gives the resulting SFH (i.e., the model that best reproduces simultaneously the observed CMD and MDF). 3.2. General Setup To run Talos and calculate the SFH, we have to determine a set of parameters associated with our data. These parameters are used to populate the synthetic models that are directly comparable to the data. From the entire CMD we used the photometry of a region that consisted of a magnitude range of 21–24.5 and a color range of −0.5–1.15, which we denominated the photometric CMD region (blue dashed box on Figure 1 ). The colors and magnitudes of the stars in the photometric CMD region are compared to the different models to fit the SFH. This region was chosen to avoid CMD locations significantly affected by completeness corrections or contamination sources, while maximizing our signal. Additionally, magnitudes brighter than g = 21 were excluded to avoid regions of late stages of stellar evolution, where the different sets of isochrones we tried (Teramo, Dartmouth, and Yonsei-Yale) differed significantly from each other. The individual bins that defined the Hess diagrams were chosen to have a size of 0.1 in magnitude and 0.025 in color. These dimensions were selected to be small enough to be able to trace the different features of the stellar populations in the CMD, and big enough to avoid significant shot noise in each bin. To construct the MDF of the data and the different models, Talos uses a region of the CMD where significant spectroscopic data exist, which we denominated the spectroscopic CMD region (green solid box on Figure 1 ). In our case, this region of the CMD had a g − r color range of 0.5–1.25 and a g- magnitude range of 18–20.5. Then, each time Talos generates a model stellar population, it constructs the associated artificial MDF with the metallicity values of all the stars from the model that lie in the spectroscopic CMD region. Analogously,