7 Conclusions

Figure 9: Example of an observed x-axis light profile ( thick solid-line) and its corresponding best fit ( thin solid-line). The dotted-lines correspond to the two Gaussian components, being the dot-dashed-line the sum of these two components. The underlying emission (background) is represented by the dashed-line. The approximate positions for the 8 points used for defining the initial set of parameters are also shown. The spatial scale of the image was 0 $.\!\!^{\prime\prime}$333 pixel-1

In this paper, the first of two, we have presented the observations and data analysis for the optical-near-infrared study of the Blue Compact Dwarf galaxy Mrk 86. We have taken BVRJHK, H$\alpha$ and [O III]$\lambda$5007 Å images and long-slit optical spectroscopy for the object. Thus, using all these data,

• we have obtained the underlying population surface brightness and color profiles. The deepest R-band image yields an exponential profile for this component with extrapolated central surface brigthness of $\mu_{\mathrm{E,0}}=21.5$magarcsec^-2 and scale, $\alpha=0.88$kpc. No significant color gradients are observed in this component at distances larger 1.2-1.3kpc;
• we have cataloged and classified all the regions observed in the neighborhood of the galaxy. If these regions are associated with the galaxy have been classified as S (spectroscopically confirmed), E (confirmed by their photometric H$\alpha$ or [O III]$\lambda$5007 Å emission) or N (diffuse and placed in the galaxy central region) type regions. S and E type objects are accepted to be galactic H II regions. N objects are, probably, evolved stellar clusters, with negligible Lyman continuum emission. On the other hand, background galaxies and foreground stars are classified as B and F types, respectively;
  

  Figure 10: Original, total (reconstructed), background, original minus background model and residuals images in both axis and the average as obtained for the region #6 in the R-band. The cuts in the original, total and background images are the same and equal to the maximum and minimum value in the original image. The cuts in the residuals images correspond to plus/minus one tenth the difference between the maximum and minimum in the background averaged image. The residuals images were obtained as the original image minus the total (reconstructed) image

  
  
  

  Figure 10: continued (region #11)

  
  
  

  Figure 10: continued (region #18)

  
  
  

  Figure 10: continued (region #70)

  
  
• we have also described the set of evolutionary synthesis models used in Paper II. These models are based in those developed by Bruzual & Charlot (priv. comm.). They have been obtained for metallicities between $1/50\,Z_{\hbox{$\odot$ }}$ and $2\,Z_{\hbox{$\odot$ }}$, and burst strength ranging between 10^-4 and 1. We have included nebular continuum and recombination and forbidden lines emission. Although the contribution of the forbidden-line fluxes is quite uncertain in those regions where spectroscopic data are not available, the contribution of these lines in the RJHK bands is negligible and lower than 8 per cent for the BV-bands (assuming an EW(H $\alpha)\sim100$ Å);
• the optical-near-infrared colors, fluxes, emission line intensities of the S, E and N regions have been measured. Optical and near-infrared colors have been measured. The physical properties of the galaxy star-forming regions will be derived in Paper II, comparing these data with the evolutionary synthesis models developed. This comparison will be performed using a method based in the combination of Monte Carlo simulations, a maximum likelihood estimator, a single linkage clustering anaylisis method and the Principal Component Analysis (PCA);
• finally, we provide optical-near-infrared colors and spectroscopic indexes for the central starburst component.