tokens: resolution. In order to compare clumps in our galaxies with those in high-redshift galaxies, we identified clumps by visual inspection of the z = 2 images in the F435W band. Measurements were made on the original non-redshifted images since the simulated redshifted images were Gauss-blurred and re-pixelated with artificial noise added, so flux would have been difficult to determine accurately. Instead, contour plots were made on the local images and compared with the z = 2 images where the clumps were distinct. In practice, the contours at 10× sky σ on the local images matched the clumps in the high -z images, so that is where the boxes were defined for photometry. The IRAF task imstat was used to determine total pixels and mean counts per pixel within the boxes. Magnitudes were then determined for each clump, using the zero-points from the WFC3 and ACS handbooks. There was no background subtraction, because the photometric fitting described below included an underlying component plus the star-forming component, described further below. This is the same procedure as we used in measuring clumps in high-redshift galaxies (Elmegreen et al. 2009b ), so our results for clumps in our galaxies can be directly compared to the high-redshift results. For the galaxies in this paper, this means the clump boundaries sometimes contain more than one large clump, since some get blended at high z . The measured clumps are indicated as boxes in Figure 8 . For Haro 11, contour plots are also shown as an example of how clumps were identified. The right-hand contour plot is on the simulated z = 2 F435W image, where the three clumps are distinct. The middle contour plot on the original image has an arrow indicating the ∼10× sky σ contour where the boxes were then drawn. A total of 51 clumps were identified in the seven galaxies (the number in each galaxy is listed in Table 1 ). The average absolute B- band magnitude of the clumps for the seven galaxies in this sample is −15.4 ± 2.6, while the average ( B − V ) color is 0.4 ± 0.5. The clump diameters are approximated by the square root of the area of the boxes defined for photometry, and range from 170 pc to 2.9 kpc, with an average of 1.0 ± 0.7 kpc. Figure 8. The seven galaxies studied here are shown in the F555W filter. Boxes identify the clumps that were measured; see Figures 1 – 4 for physical scales. For Haro 11, contour plots are also shown to indicate how clumps were identified. Measurements were done on the non-redshifted images for the boundaries determined from the redshifted images. In practice, these boundaries were at a surface brightness ∼10× sky σ in the F435W image, as indicated in the middle image. The right-hand contour plot is for the simulated z = 2 F435W image, where the three clumps are distinct. 4.2. Clump Ages and Masses The photometric measurements of the clumps were used to determine ages, masses, and extinctions through spectral energy distribution (SED) fitting, as detailed in Elmegreen
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