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Appendix A: Spectroscopic redshifts and systematic shifts

Table A.1 gives the number of very secure spectroscopic redshift available for galaxies that lie within the CLASH/HST fields of view. Most spec-z’s have been targeted by the VIMOS/VLT Large Program 186.A-0798 (Rosati, in prep.). Other spec-z come from GISMO observations on Magellan telescopes, VLT observations (Lamareille et al. 2006), the 6DF survey (Jones et al. 2004), the SDSS DR7 (Abazajian et al. 2009), the MMT/Hectospec survey (Fabricant et al. 2005; Rines et al. 2013) and archival data from Ebeling et al. (2009); Sand et al. (2008); Smith et al. (2005); Newman et al. (2011); Richard et al. (2011); Guzzo et al. (2009); Halkola et al. (2008); Cohen & Kneib (2002); Stern et al. (2010).

Using the spec-z listed in Table A.1, we derive systematic shifts that we apply to the CLASH photometry as a first order template correction for Le Phare photo-z. These shifts are not applied to BPZ photo-z. Using different sets of photometry and different types of photometry change the shift’s values. In Table A.2, we list the shift’s values from using the different sub-sets of the CLASH photometry that are defined in Sect. 4.2.

Appendix B: The odds and pdz_best photo-z confidence values

	Fig. B.1 Left panel: magnitude error as a function of odds and pdz_best parameter for MACS1206 galaxy cluster. The black dots and blue stars show respectively Le Phare and BPZ results. Right panel: percentage of galaxies left after a cut in the pdz_best parameter for Le Phare in solid lines and odds parameter for BPZ in dashed lines for MACS1206 galaxy cluster at different F814W magnitudes limit.
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The top panel of Fig. B.1 shows the error on the F814W magnitude as a function of the odds parameter of BPZ in black and pdz_best parameter of Le Phare in blue for MACS1206 galaxy cluster. Bright galaxies have higher odds than faint galaxies, as one can expect. We note that some Le Phare pdz_best values are higher than maximum possible value 100. This is a numerical issue during the integration of the p(z). It usually means that the p(z) is very narrow and can be assumed as high value of pdz_best.

The bottom panel of Fig. B.1 shows the percentage of galaxies left after a selection cut based on pdz_best Le Phare in solid lines and odds BPZ in dashed lines at different F814W magnitude based on MACS1206 galaxy cluster photo-z for all galaxies in the HST field. We note that to remove the same percentage of galaxies, one needs a higher cut for the BPZ odds parameter than with Le Phare pdz_best.

shows a comparison between Le Phare and BPZ when selecting the best 85% BPZ χ² or Le Phare pdz_best as well as a number of detections selection.

We note that BPZ odds have values between 0 and 1 that we rescale at 0 to 100 in order to have the same scale between Le Phare pdz_best and BPZ odds.

	Fig. B.2 Le Phare and BPZ photo-z comparison for samples of galaxies selected as a function of the number of detections using the best 85% BPZ χ2 or Le Phare pdz_best values. The left panels show the mean values of BPZ-Le Phare photo-z for the different samples. The right panels show the fraction of galaxies selected by bins of magnitude and redshift.
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Appendix C: Arcs

In this section, we show the photo-z results from the BPZ code for the standard isophotal photometry for each of the lensed images of MACS1206 systems. These results are to be compared with those shown in Sect. 5 for Le Phare. We show stamps images of each arcs, SExtractor segmentation map for the isophotal photometry, the probability of the photo-z an the

best-fit template of the BPZ results from the first left column to last column. The aperture shape of the SExtractor isophotal photometry is showed by the black contour on the second column from the left. When comparing these figures to Fig. 12 we note that the tailored photometry and the isophotal SExtractor photometry have different shapes. Photo-z derive from both shapes using the same photo-z code usually prefers the tailored photometry as explained in Sect. 5.

	Fig. C.1 BPZ photometric redshift results for the strongly lensed system 1 standard photometry from SExtractor isophotal apertures. From top to bottom, figures are cut-out images of the arcs, segmentation map of the isophotal photometry, probability of the photometric redshift and best-fit template for the arcs considered. From left to right, figures show arc 1.1, 1.2, and 1.3.
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	Fig. C.2 BPZ photometric redshift results for the strongly lensed system 2 standard photometry from SExtractor isophotal apertures. From top to bottom, figures are cut-out images of the arcs, segmentation map of the isophotal photometry, probability of the photometric redshift and best-fit template for the arcs considered. From left to right, figures show arc 2.1, 2.2, and 2.3.
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	Fig. C.3 BPZ photometric redshift results for the strongly lensed system 3 standard photometry from SExtractor isophotal apertures. From top to bottom, figures are cut-out images of the arcs, segmentation map of the isophotal photometry, probability of the photometric redshift and best-fit template for the arcs considered. From left to right, figures show arc 3.1, 3.2, and 3.3.
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	Fig. C.4 BPZ photometric redshift results for the strongly lensed system 4 standard photometry from SExtractor isophotal apertures. From top to bottom, figures are cut-out images of the arcs, segmentation map of the isophotal photometry, probability of the photometric redshift and best-fit template for the arcs considered. From left to right, figures show arc 4.1, 4.2, 4.3.
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	Fig. C.5 BPZ photometric redshift results for the strongly lensed system 4 standard photometry from SExtractor isophotal apertures. From top to bottom, figures are cut-out images of the arcs, segmentation map of the isophotal photometry, probability of the photometric redshift and best-fit template for the arcs considered. From left to right, figures show arc 4.4 and 4.5.
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© ESO, 2014