Dark energy survey year 1 results: Redshift distributions of the weak-lensing source galaxies

B. Hoyle; D. Gruen; G. M. Bernstein; M. M. Rau; J. De Vicente; W. G. Hartley; E. Gaztanaga; J. DeRose; M. A. Troxel; C. Davis; A. Alarcon; N. MacCrann; J. Prat; C. Sánchez; E. Sheldon; R. H. Wechsler; J. Asorey; M. R. Becker; C. Bonnett; A. Carnero Rosell; D. Carollo; M. Carrasco Kind; F. J. Castander; R. Cawthon; C. Chang; M. Childress; T. M. Davis; A. Drlica-Wagner; M. Gatti; K. Glazebrook; J. Gschwend; S. R. Hinton; J. K. Hoormann; A. G. Kim; A. King; K. Kuehn; G. Lewis; C. Lidman; H. Lin; E. Macaulay; M. A.G. Maia; P. Martini; D. Mudd; A. Möller; R. C. Nichol; R. L.C. Ogando; R. P. Rollins; A. Roodman; A. J. Ross; E. Rozo; E. S. Rykoff; S. Samuroff; I. Sevilla-Noarbe; R. Sharp; N. E. Sommer; B. E. Tucker; S. A. Uddin; T. N. Varga; P. Vielzeuf; F. Yuan; B. Zhang; T. M.C. Abbott; F. B. Abdalla; S. Allam; J. Annis; K. Bechtol; A. Benoit-Lévy; E. Bertin; D. Brooks; E. Buckley-Geer; D. L. Burke; M. T. Busha; D. Capozzi; J. Carretero; M. Crocce; C. B. D'Andrea; L. N. da Costa; D. L. DePoy; S. Desai; H. T. Diehl; P. Doel; T. F. Eifler; J. Estrada; A. E. Evrard; E. Fernandez; B. Flaugher; P. Fosalba; J. Frieman; J. García-Bellido; D. W. Gerdes; T. Giannantonio; D. A. Goldstein; R. A. Gruendl; G. Gutierrez; K. Honscheid; D. J. James; M. Jarvis; T. Jeltema; M. W.G. Johnson; M. D. Johnson

doi:10.1093/mnras/sty957

Dark energy survey year 1 results: Redshift distributions of the weak-lensing source galaxies

B. Hoyle, D. Gruen, G. M. Bernstein, M. M. Rau, J. De Vicente, W. G. Hartley, E. Gaztanaga, J. DeRose, M. A. Troxel, C. Davis, A. Alarcon, N. MacCrann, J. Prat, C. Sánchez, E. Sheldon, R. H. Wechsler, J. Asorey, M. R. Becker, C. Bonnett, A. Carnero RosellD. Carollo, M. Carrasco Kind, F. J. Castander, R. Cawthon, C. Chang, M. Childress, T. M. Davis, A. Drlica-Wagner, M. Gatti, K. Glazebrook, J. Gschwend, S. R. Hinton, J. K. Hoormann, A. G. Kim, A. King, K. Kuehn, G. Lewis, C. Lidman, H. Lin, E. Macaulay, M. A.G. Maia, P. Martini, D. Mudd, A. Möller, R. C. Nichol, R. L.C. Ogando, R. P. Rollins, A. Roodman, A. J. Ross, E. Rozo, E. S. Rykoff, S. Samuroff, I. Sevilla-Noarbe, R. Sharp, N. E. Sommer, B. E. Tucker, S. A. Uddin, T. N. Varga, P. Vielzeuf, F. Yuan, B. Zhang, T. M.C. Abbott, F. B. Abdalla, S. Allam, J. Annis, K. Bechtol, A. Benoit-Lévy, E. Bertin, D. Brooks, E. Buckley-Geer, D. L. Burke, M. T. Busha, D. Capozzi, J. Carretero, M. Crocce, C. B. D'Andrea, L. N. da Costa, D. L. DePoy, S. Desai, H. T. Diehl, P. Doel, T. F. Eifler, J. Estrada, A. E. Evrard, E. Fernandez, B. Flaugher, P. Fosalba, J. Frieman, J. García-Bellido, D. W. Gerdes, T. Giannantonio, D. A. Goldstein, R. A. Gruendl, G. Gutierrez, K. Honscheid, D. J. James, M. Jarvis, T. Jeltema, M. W.G. Johnson, M. D. Johnson

Research output: Contribution to journal › Article › Research › peer-review

73 Citations (Scopus)

Abstract

© 2018 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. We describe the derivation and validation of redshift distribution estimates and their uncertainties for the populations of galaxies used as weak-lensing sources in the Dark Energy Survey (DES) Year 1 cosmological analyses. The Bayesian Photometric Redshift (BPZ) code is used to assign galaxies to four redshift bins between z ≈ 0.2 and ≈1.3, and to produce initial estimates of the lensing-weighted redshift distributions nPZi(z) ∝ dni/dz for members of bin i. Accurate determination of cosmological parameters depends critically on knowledge of ni, but is insensitive to bin assignments or redshift errors for individual galaxies. The cosmological analyses allow for shifts ni (z) = nPZi(z - Δzi) to correct themean redshift of ni(z) for biases in nPZi. The Δzi are constrained by comparison of independently estimated 30-band photometric redshifts of galaxies in the Cosmic Evolution Survey (COSMOS) field to BPZ estimates made from the DES griz fluxes, for a sample matched in fluxes, pre-seeing size, and lensing weight to the DES weak-lensing sources. In companion papers, the Δzi of the three lowest redshift bins are further constrained by the angular clustering of the source galaxies around red galaxies with secure photometric redshifts at 0.15 < z < 0.9. This paper details the BPZ and COSMOS procedures, and demonstrates that the cosmological inference is insensitive to details of the ni(z) beyond the choice of Δzi. The clustering and COSMOS validation methods produce consistent estimates of Δzi in the bins where both can be applied, with combined uncertainties of σΔzi = 0.015, 0.013, 0.011, and 0.022 in the four bins. Repeating the photo-z procedure instead using the Directional Neighbourhood Fitting algorithm, or using the ni(z) estimated from the matched sample in COSMOS, yields no discernible difference in cosmological inferences.

Original language	English
Pages (from-to)	592-610
Journal	Monthly Notices of the Royal Astronomical Society
Volume	478
Issue number	1
DOIs	https://doi.org/10.1093/mnras/sty957
Publication status	Published - 21 Jul 2018

Keywords

Catalogues
Methods: Data analysis
Surveys

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Hoyle, B., Gruen, D., Bernstein, G. M., Rau, M. M., De Vicente, J., Hartley, W. G., Gaztanaga, E., DeRose, J., Troxel, M. A., Davis, C., Alarcon, A., MacCrann, N., Prat, J., Sánchez, C., Sheldon, E., Wechsler, R. H., Asorey, J., Becker, M. R., Bonnett, C., ... Johnson, M. D. (2018). Dark energy survey year 1 results: Redshift distributions of the weak-lensing source galaxies. Monthly Notices of the Royal Astronomical Society, 478(1), 592-610. https://doi.org/10.1093/mnras/sty957

Hoyle, B. ; Gruen, D. ; Bernstein, G. M. ; Rau, M. M. ; De Vicente, J. ; Hartley, W. G. ; Gaztanaga, E. ; DeRose, J. ; Troxel, M. A. ; Davis, C. ; Alarcon, A. ; MacCrann, N. ; Prat, J. ; Sánchez, C. ; Sheldon, E. ; Wechsler, R. H. ; Asorey, J. ; Becker, M. R. ; Bonnett, C. ; Rosell, A. Carnero ; Carollo, D. ; Kind, M. Carrasco ; Castander, F. J. ; Cawthon, R. ; Chang, C. ; Childress, M. ; Davis, T. M. ; Drlica-Wagner, A. ; Gatti, M. ; Glazebrook, K. ; Gschwend, J. ; Hinton, S. R. ; Hoormann, J. K. ; Kim, A. G. ; King, A. ; Kuehn, K. ; Lewis, G. ; Lidman, C. ; Lin, H. ; Macaulay, E. ; Maia, M. A.G. ; Martini, P. ; Mudd, D. ; Möller, A. ; Nichol, R. C. ; Ogando, R. L.C. ; Rollins, R. P. ; Roodman, A. ; Ross, A. J. ; Rozo, E. ; Rykoff, E. S. ; Samuroff, S. ; Sevilla-Noarbe, I. ; Sharp, R. ; Sommer, N. E. ; Tucker, B. E. ; Uddin, S. A. ; Varga, T. N. ; Vielzeuf, P. ; Yuan, F. ; Zhang, B. ; Abbott, T. M.C. ; Abdalla, F. B. ; Allam, S. ; Annis, J. ; Bechtol, K. ; Benoit-Lévy, A. ; Bertin, E. ; Brooks, D. ; Buckley-Geer, E. ; Burke, D. L. ; Busha, M. T. ; Capozzi, D. ; Carretero, J. ; Crocce, M. ; D'Andrea, C. B. ; da Costa, L. N. ; DePoy, D. L. ; Desai, S. ; Diehl, H. T. ; Doel, P. ; Eifler, T. F. ; Estrada, J. ; Evrard, A. E. ; Fernandez, E. ; Flaugher, B. ; Fosalba, P. ; Frieman, J. ; García-Bellido, J. ; Gerdes, D. W. ; Giannantonio, T. ; Goldstein, D. A. ; Gruendl, R. A. ; Gutierrez, G. ; Honscheid, K. ; James, D. J. ; Jarvis, M. ; Jeltema, T. ; Johnson, M. W.G. ; Johnson, M. D. / Dark energy survey year 1 results: Redshift distributions of the weak-lensing source galaxies. In: Monthly Notices of the Royal Astronomical Society. 2018 ; Vol. 478, No. 1. pp. 592-610.

@article{44a38549fa9e4765aeee9f43dd06b3ac,

title = "Dark energy survey year 1 results: Redshift distributions of the weak-lensing source galaxies",

abstract = "{\textcopyright} 2018 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. We describe the derivation and validation of redshift distribution estimates and their uncertainties for the populations of galaxies used as weak-lensing sources in the Dark Energy Survey (DES) Year 1 cosmological analyses. The Bayesian Photometric Redshift (BPZ) code is used to assign galaxies to four redshift bins between z ≈ 0.2 and ≈1.3, and to produce initial estimates of the lensing-weighted redshift distributions nPZi(z) ∝ dni/dz for members of bin i. Accurate determination of cosmological parameters depends critically on knowledge of ni, but is insensitive to bin assignments or redshift errors for individual galaxies. The cosmological analyses allow for shifts ni (z) = nPZi(z - Δzi) to correct themean redshift of ni(z) for biases in nPZi. The Δzi are constrained by comparison of independently estimated 30-band photometric redshifts of galaxies in the Cosmic Evolution Survey (COSMOS) field to BPZ estimates made from the DES griz fluxes, for a sample matched in fluxes, pre-seeing size, and lensing weight to the DES weak-lensing sources. In companion papers, the Δzi of the three lowest redshift bins are further constrained by the angular clustering of the source galaxies around red galaxies with secure photometric redshifts at 0.15 < z < 0.9. This paper details the BPZ and COSMOS procedures, and demonstrates that the cosmological inference is insensitive to details of the ni(z) beyond the choice of Δzi. The clustering and COSMOS validation methods produce consistent estimates of Δzi in the bins where both can be applied, with combined uncertainties of σΔzi = 0.015, 0.013, 0.011, and 0.022 in the four bins. Repeating the photo-z procedure instead using the Directional Neighbourhood Fitting algorithm, or using the ni(z) estimated from the matched sample in COSMOS, yields no discernible difference in cosmological inferences.",

keywords = "Catalogues, Methods: Data analysis, Surveys",

author = "B. Hoyle and D. Gruen and Bernstein, {G. M.} and Rau, {M. M.} and {De Vicente}, J. and Hartley, {W. G.} and E. Gaztanaga and J. DeRose and Troxel, {M. A.} and C. Davis and A. Alarcon and N. MacCrann and J. Prat and C. S{\'a}nchez and E. Sheldon and Wechsler, {R. H.} and J. Asorey and Becker, {M. R.} and C. Bonnett and Rosell, {A. Carnero} and D. Carollo and Kind, {M. Carrasco} and Castander, {F. J.} and R. Cawthon and C. Chang and M. Childress and Davis, {T. M.} and A. Drlica-Wagner and M. Gatti and K. Glazebrook and J. Gschwend and Hinton, {S. R.} and Hoormann, {J. K.} and Kim, {A. G.} and A. King and K. Kuehn and G. Lewis and C. Lidman and H. Lin and E. Macaulay and Maia, {M. A.G.} and P. Martini and D. Mudd and A. M{\"o}ller and Nichol, {R. C.} and Ogando, {R. L.C.} and Rollins, {R. P.} and A. Roodman and Ross, {A. J.} and E. Rozo and Rykoff, {E. S.} and S. Samuroff and I. Sevilla-Noarbe and R. Sharp and Sommer, {N. E.} and Tucker, {B. E.} and Uddin, {S. A.} and Varga, {T. N.} and P. Vielzeuf and F. Yuan and B. Zhang and Abbott, {T. M.C.} and Abdalla, {F. B.} and S. Allam and J. Annis and K. Bechtol and A. Benoit-L{\'e}vy and E. Bertin and D. Brooks and E. Buckley-Geer and Burke, {D. L.} and Busha, {M. T.} and D. Capozzi and J. Carretero and M. Crocce and D'Andrea, {C. B.} and {da Costa}, {L. N.} and DePoy, {D. L.} and S. Desai and Diehl, {H. T.} and P. Doel and Eifler, {T. F.} and J. Estrada and Evrard, {A. E.} and E. Fernandez and B. Flaugher and P. Fosalba and J. Frieman and J. Garc{\'i}a-Bellido and Gerdes, {D. W.} and T. Giannantonio and Goldstein, {D. A.} and Gruendl, {R. A.} and G. Gutierrez and K. Honscheid and James, {D. J.} and M. Jarvis and T. Jeltema and Johnson, {M. W.G.} and Johnson, {M. D.}",

year = "2018",

month = jul,

day = "21",

doi = "10.1093/mnras/sty957",

language = "English",

volume = "478",

pages = "592--610",

journal = "Monthly Notices of the Royal Astronomical Society",

issn = "0035-8711",

number = "1",

}

Hoyle, B, Gruen, D, Bernstein, GM, Rau, MM, De Vicente, J, Hartley, WG, Gaztanaga, E, DeRose, J, Troxel, MA, Davis, C, Alarcon, A, MacCrann, N, Prat, J, Sánchez, C, Sheldon, E, Wechsler, RH, Asorey, J, Becker, MR, Bonnett, C, Rosell, AC, Carollo, D, Kind, MC, Castander, FJ, Cawthon, R, Chang, C, Childress, M, Davis, TM, Drlica-Wagner, A, Gatti, M, Glazebrook, K, Gschwend, J, Hinton, SR, Hoormann, JK, Kim, AG, King, A, Kuehn, K, Lewis, G, Lidman, C, Lin, H, Macaulay, E, Maia, MAG, Martini, P, Mudd, D, Möller, A, Nichol, RC, Ogando, RLC, Rollins, RP, Roodman, A, Ross, AJ, Rozo, E, Rykoff, ES, Samuroff, S, Sevilla-Noarbe, I, Sharp, R, Sommer, NE, Tucker, BE, Uddin, SA, Varga, TN, Vielzeuf, P, Yuan, F, Zhang, B, Abbott, TMC, Abdalla, FB, Allam, S, Annis, J, Bechtol, K, Benoit-Lévy, A, Bertin, E, Brooks, D, Buckley-Geer, E, Burke, DL, Busha, MT, Capozzi, D, Carretero, J, Crocce, M, D'Andrea, CB, da Costa, LN, DePoy, DL, Desai, S, Diehl, HT, Doel, P, Eifler, TF, Estrada, J, Evrard, AE, Fernandez, E, Flaugher, B, Fosalba, P, Frieman, J, García-Bellido, J, Gerdes, DW, Giannantonio, T, Goldstein, DA, Gruendl, RA, Gutierrez, G, Honscheid, K, James, DJ, Jarvis, M, Jeltema, T, Johnson, MWG & Johnson, MD 2018, 'Dark energy survey year 1 results: Redshift distributions of the weak-lensing source galaxies', Monthly Notices of the Royal Astronomical Society, vol. 478, no. 1, pp. 592-610. https://doi.org/10.1093/mnras/sty957

Dark energy survey year 1 results: Redshift distributions of the weak-lensing source galaxies. / Hoyle, B.; Gruen, D.; Bernstein, G. M.; Rau, M. M.; De Vicente, J.; Hartley, W. G.; Gaztanaga, E.; DeRose, J.; Troxel, M. A.; Davis, C.; Alarcon, A.; MacCrann, N.; Prat, J.; Sánchez, C.; Sheldon, E.; Wechsler, R. H.; Asorey, J.; Becker, M. R.; Bonnett, C.; Rosell, A. Carnero; Carollo, D.; Kind, M. Carrasco; Castander, F. J.; Cawthon, R.; Chang, C.; Childress, M.; Davis, T. M.; Drlica-Wagner, A.; Gatti, M.; Glazebrook, K.; Gschwend, J.; Hinton, S. R.; Hoormann, J. K.; Kim, A. G.; King, A.; Kuehn, K.; Lewis, G.; Lidman, C.; Lin, H.; Macaulay, E.; Maia, M. A.G.; Martini, P.; Mudd, D.; Möller, A.; Nichol, R. C.; Ogando, R. L.C.; Rollins, R. P.; Roodman, A.; Ross, A. J.; Rozo, E.; Rykoff, E. S.; Samuroff, S.; Sevilla-Noarbe, I.; Sharp, R.; Sommer, N. E.; Tucker, B. E.; Uddin, S. A.; Varga, T. N.; Vielzeuf, P.; Yuan, F.; Zhang, B.; Abbott, T. M.C.; Abdalla, F. B.; Allam, S.; Annis, J.; Bechtol, K.; Benoit-Lévy, A.; Bertin, E.; Brooks, D.; Buckley-Geer, E.; Burke, D. L.; Busha, M. T.; Capozzi, D.; Carretero, J.; Crocce, M.; D'Andrea, C. B.; da Costa, L. N.; DePoy, D. L.; Desai, S.; Diehl, H. T.; Doel, P.; Eifler, T. F.; Estrada, J.; Evrard, A. E.; Fernandez, E.; Flaugher, B.; Fosalba, P.; Frieman, J.; García-Bellido, J.; Gerdes, D. W.; Giannantonio, T.; Goldstein, D. A.; Gruendl, R. A.; Gutierrez, G.; Honscheid, K.; James, D. J.; Jarvis, M.; Jeltema, T.; Johnson, M. W.G.; Johnson, M. D.

In: Monthly Notices of the Royal Astronomical Society, Vol. 478, No. 1, 21.07.2018, p. 592-610.

Research output: Contribution to journal › Article › Research › peer-review

TY - JOUR

T1 - Dark energy survey year 1 results: Redshift distributions of the weak-lensing source galaxies

AU - Hoyle, B.

AU - Gruen, D.

AU - Bernstein, G. M.

AU - Rau, M. M.

AU - De Vicente, J.

AU - Hartley, W. G.

AU - Gaztanaga, E.

AU - DeRose, J.

AU - Troxel, M. A.

AU - Davis, C.

AU - Alarcon, A.

AU - MacCrann, N.

AU - Prat, J.

AU - Sánchez, C.

AU - Sheldon, E.

AU - Wechsler, R. H.

AU - Asorey, J.

AU - Becker, M. R.

AU - Bonnett, C.

AU - Rosell, A. Carnero

AU - Carollo, D.

AU - Kind, M. Carrasco

AU - Castander, F. J.

AU - Cawthon, R.

AU - Chang, C.

AU - Childress, M.

AU - Davis, T. M.

AU - Drlica-Wagner, A.

AU - Gatti, M.

AU - Glazebrook, K.

AU - Gschwend, J.

AU - Hinton, S. R.

AU - Hoormann, J. K.

AU - Kim, A. G.

AU - King, A.

AU - Kuehn, K.

AU - Lewis, G.

AU - Lidman, C.

AU - Lin, H.

AU - Macaulay, E.

AU - Maia, M. A.G.

AU - Martini, P.

AU - Mudd, D.

AU - Möller, A.

AU - Nichol, R. C.

AU - Ogando, R. L.C.

AU - Rollins, R. P.

AU - Roodman, A.

AU - Ross, A. J.

AU - Rozo, E.

AU - Rykoff, E. S.

AU - Samuroff, S.

AU - Sevilla-Noarbe, I.

AU - Sharp, R.

AU - Sommer, N. E.

AU - Tucker, B. E.

AU - Uddin, S. A.

AU - Varga, T. N.

AU - Vielzeuf, P.

AU - Yuan, F.

AU - Zhang, B.

AU - Abbott, T. M.C.

AU - Abdalla, F. B.

AU - Allam, S.

AU - Annis, J.

AU - Bechtol, K.

AU - Benoit-Lévy, A.

AU - Bertin, E.

AU - Brooks, D.

AU - Buckley-Geer, E.

AU - Burke, D. L.

AU - Busha, M. T.

AU - Capozzi, D.

AU - Carretero, J.

AU - Crocce, M.

AU - D'Andrea, C. B.

AU - da Costa, L. N.

AU - DePoy, D. L.

AU - Desai, S.

AU - Diehl, H. T.

AU - Doel, P.

AU - Eifler, T. F.

AU - Estrada, J.

AU - Evrard, A. E.

AU - Fernandez, E.

AU - Flaugher, B.

AU - Fosalba, P.

AU - Frieman, J.

AU - García-Bellido, J.

AU - Gerdes, D. W.

AU - Giannantonio, T.

AU - Goldstein, D. A.

AU - Gruendl, R. A.

AU - Gutierrez, G.

AU - Honscheid, K.

AU - James, D. J.

AU - Jarvis, M.

AU - Jeltema, T.

AU - Johnson, M. W.G.

AU - Johnson, M. D.

PY - 2018/7/21

Y1 - 2018/7/21

N2 - © 2018 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. We describe the derivation and validation of redshift distribution estimates and their uncertainties for the populations of galaxies used as weak-lensing sources in the Dark Energy Survey (DES) Year 1 cosmological analyses. The Bayesian Photometric Redshift (BPZ) code is used to assign galaxies to four redshift bins between z ≈ 0.2 and ≈1.3, and to produce initial estimates of the lensing-weighted redshift distributions nPZi(z) ∝ dni/dz for members of bin i. Accurate determination of cosmological parameters depends critically on knowledge of ni, but is insensitive to bin assignments or redshift errors for individual galaxies. The cosmological analyses allow for shifts ni (z) = nPZi(z - Δzi) to correct themean redshift of ni(z) for biases in nPZi. The Δzi are constrained by comparison of independently estimated 30-band photometric redshifts of galaxies in the Cosmic Evolution Survey (COSMOS) field to BPZ estimates made from the DES griz fluxes, for a sample matched in fluxes, pre-seeing size, and lensing weight to the DES weak-lensing sources. In companion papers, the Δzi of the three lowest redshift bins are further constrained by the angular clustering of the source galaxies around red galaxies with secure photometric redshifts at 0.15 < z < 0.9. This paper details the BPZ and COSMOS procedures, and demonstrates that the cosmological inference is insensitive to details of the ni(z) beyond the choice of Δzi. The clustering and COSMOS validation methods produce consistent estimates of Δzi in the bins where both can be applied, with combined uncertainties of σΔzi = 0.015, 0.013, 0.011, and 0.022 in the four bins. Repeating the photo-z procedure instead using the Directional Neighbourhood Fitting algorithm, or using the ni(z) estimated from the matched sample in COSMOS, yields no discernible difference in cosmological inferences.

AB - © 2018 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. We describe the derivation and validation of redshift distribution estimates and their uncertainties for the populations of galaxies used as weak-lensing sources in the Dark Energy Survey (DES) Year 1 cosmological analyses. The Bayesian Photometric Redshift (BPZ) code is used to assign galaxies to four redshift bins between z ≈ 0.2 and ≈1.3, and to produce initial estimates of the lensing-weighted redshift distributions nPZi(z) ∝ dni/dz for members of bin i. Accurate determination of cosmological parameters depends critically on knowledge of ni, but is insensitive to bin assignments or redshift errors for individual galaxies. The cosmological analyses allow for shifts ni (z) = nPZi(z - Δzi) to correct themean redshift of ni(z) for biases in nPZi. The Δzi are constrained by comparison of independently estimated 30-band photometric redshifts of galaxies in the Cosmic Evolution Survey (COSMOS) field to BPZ estimates made from the DES griz fluxes, for a sample matched in fluxes, pre-seeing size, and lensing weight to the DES weak-lensing sources. In companion papers, the Δzi of the three lowest redshift bins are further constrained by the angular clustering of the source galaxies around red galaxies with secure photometric redshifts at 0.15 < z < 0.9. This paper details the BPZ and COSMOS procedures, and demonstrates that the cosmological inference is insensitive to details of the ni(z) beyond the choice of Δzi. The clustering and COSMOS validation methods produce consistent estimates of Δzi in the bins where both can be applied, with combined uncertainties of σΔzi = 0.015, 0.013, 0.011, and 0.022 in the four bins. Repeating the photo-z procedure instead using the Directional Neighbourhood Fitting algorithm, or using the ni(z) estimated from the matched sample in COSMOS, yields no discernible difference in cosmological inferences.

KW - Catalogues

KW - Methods: Data analysis

KW - Surveys

U2 - 10.1093/mnras/sty957

DO - 10.1093/mnras/sty957

M3 - Article

VL - 478

SP - 592

EP - 610

JO - Monthly Notices of the Royal Astronomical Society

JF - Monthly Notices of the Royal Astronomical Society

SN - 0035-8711

IS - 1

ER -