Phenotypic redshifts with self-organizing maps: A novel method to characterize redshift distributions of source galaxies for weak lensing

Journal Article · Fri Aug 09 00:00:00 EDT 2019 · Monthly Notices of the Royal Astronomical Society

DOI:https://doi.org/10.1093/mnras/stz2162· OSTI ID:1558844

Buchs, R.  ^[1]; Davis, C.  ^[2]; Gruen, D.  ^[3]; DeRose, J. ^[4]; Alarcon, A. ^[5]; Bernstein, G. M. ^[6]; Sánchez, C. ^[6]; Myles, J. ^[7]; Roodman, A. ^[8]; Allen, S. ^[7]; Amon, A. ^[9]; Choi, A. ^[10]; Masters, D. C. ^[11]; Miquel, R. ^[12]; Troxel, M. A. ^[13]; Wechsler, R. H. ^[3]; Abbott, T. M. C. ^[14]; Annis, J. ^[15]; Avila, S. ^[16]; Bechtol, K. ^[17] ; Bridle, S. L. ^[18]; Brooks, D. ^[19]; Buckley-Geer, E. ^[15]; Burke, D. L. ^[8]; Carnero Rosell, A. ^[20]; Carrasco Kind, M. ^[21]; Carretero, J. ^[22]; Castander, F. J. ^[5]; Cawthon, R. ^[23]; D’Andrea, C. B. ^[6]; da Costa, L. N. ^[24]; De Vicente, J. ^[25]; Desai, S. ^[26]; Diehl, H. T. ^[15]; Doel, P. ^[19]; Drlica-Wagner, A. ^[27]; Eifler, T. F. ^[28]; Evrard, A. E. ^[29]; Flaugher, B. ^[15]; Fosalba, P. ^[5]; Frieman, J. ^[27]; García-Bellido, J. ^[30]; Gaztanaga, E. ^[5]; Gruendl, R. A. ^[21]; Gschwend, J. ^[24]; Gutierrez, G. ^[15]; Hartley, W. G. ^[31]; Hollowood, D. L. ^[32]; Honscheid, K. ^[33]; James, D. J. ^[34]; Kuehn, K. ^[35]; Kuropatkin, N. ^[15]; Lima, M. ^[36]; Lin, H. ^[15]; Maia, M. A. G. ^[24]; March, M. ^[6]; Marshall, J. L. ^[37]; Melchior, P. ^[38]; Menanteau, F. ^[21]; Ogando, R. L. C. ^[24]; Plazas, A. A. ^[38]; Rykoff, E. S. ^[8]; Sanchez, E. ^[25]; Scarpine, V. ^[15]; Serrano, S. ^[5]; Sevilla-Noarbe, I. ^[25]; Smith, M. ^[39]; Soares-Santos, M. ^[40]; Sobreira, F. ^[41]; Suchyta, E. ^[42]; Swanson, M. E. C. ^[43]; Tarle, G. ^[44]; Thomas, D. ^[16]; Vikram, V. ^[45]

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1. SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA, Kavli Institute for Particle Astrophysics and Cosmology, P. O. Box 2450, Stanford University, Stanford, CA 94305, USA, École Polytechnique Fédérale de Lausanne, Route Cantonale, CH-1015 Lausanne, Switzerland, Institute of Science, Technology, and Policy, ETH Zurich, Universitätstrasse 41, CH-8092 Zurich, Switzerland
2. SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA, Kavli Institute for Particle Astrophysics and Cosmology, P. O. Box 2450, Stanford University, Stanford, CA 94305, USA, Descartes Labs, Inc., 100 N Guadelupe St, Santa Fe, NM 87501, USA
3. SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA, Kavli Institute for Particle Astrophysics and Cosmology, P. O. Box 2450, Stanford University, Stanford, CA 94305, USA, Department of Physics, Stanford University, 382 Via Pueblo Mall, Stanford, CA 94305, USA
4. Kavli Institute for Particle Astrophysics and Cosmology, P. O. Box 2450, Stanford University, Stanford, CA 94305, USA, Department of Physics, Stanford University, 382 Via Pueblo Mall, Stanford, CA 94305, USA
5. Institut d’Estudis Espacials de Catalunya (IEEC), E-08034 Barcelona, Spain, Institute of Space Sciences (ICE, CSIC), Campus UAB, Carrer de Can Magrans, s/n, E-08193 Barcelona, Spain
6. Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104, USA
7. Department of Physics, Stanford University, 382 Via Pueblo Mall, Stanford, CA 94305, USA
8. SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA, Kavli Institute for Particle Astrophysics and Cosmology, P. O. Box 2450, Stanford University, Stanford, CA 94305, USA
9. Kavli Institute for Particle Astrophysics and Cosmology, P. O. Box 2450, Stanford University, Stanford, CA 94305, USA
10. Center for Cosmology and Astro-Particle Physics, The Ohio State University, Columbus, OH 43210, USA
11. Infrared Processing and Analysis Center, Pasadena, CA 91125, USA, Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, CA 91109, USA
12. Institució Catalana de Recerca i Estudis Avançats, E-08010 Barcelona, Spain, Institut de Física d’Altes Energies (IFAE), The Barcelona Institute of Science and Technology, Campus UAB, E-08193 Bellaterra (Barcelona), Spain
13. Department of Physics, Duke University Durham, NC 27708, USA
14. Cerro Tololo Inter-American Observatory, National Optical Astronomy Observatory, Casilla 603, La Serena, Chile
15. Fermi National Accelerator Laboratory, P. O. Box 500, Batavia, IL 60510, USA
16. Institute of Cosmology and Gravitation, University of Portsmouth, Portsmouth PO1 3FX, UK
17. LSST, 933 North Cherry Avenue, Tucson, AZ 85721, USA, Physics Department, 2320 Chamberlin Hall, University of Wisconsin-Madison, 1150 University Avenue Madison, WI 53706, USA
18. Jodrell Bank Center for Astrophysics, School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL, UK
19. Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK
20. Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), E-28040 Madrid, Spain, Laboratório Interinstitucional de e-Astronomia - LIneA, Rua Gal. José Cristino 77, Rio de Janeiro RJ - 20921-400, Brazil
21. Department of Astronomy, University of Illinois at Urbana-Champaign, 1002 W, Green Street, Urbana, IL 61801, USA, National Center for Supercomputing Applications, 1205 West Clark St., Urbana, IL 61801, USA
22. Institut de Física d’Altes Energies (IFAE), The Barcelona Institute of Science and Technology, Campus UAB, E-08193 Bellaterra (Barcelona), Spain
23. Physics Department, 2320 Chamberlin Hall, University of Wisconsin-Madison, 1150 University Avenue Madison, WI 53706, USA
24. Laboratório Interinstitucional de e-Astronomia - LIneA, Rua Gal. José Cristino 77, Rio de Janeiro RJ - 20921-400, Brazil, Observatório Nacional, Rua Gal. José Cristino 77, Rio de Janeiro RJ - 20921-400, Brazil
25. Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), E-28040 Madrid, Spain
26. Department of Physics, IIT Hyderabad, Kandi, Telangana 502285, India
27. Fermi National Accelerator Laboratory, P. O. Box 500, Batavia, IL 60510, USA, Kavli Institute for Cosmological Physics, University of Chicago, Chicago, IL 60637, USA
28. Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, CA 91109, USA, Department of Astronomy/Steward Observatory, 933 North Cherry Avenue, Tucson, AZ 85721-0065, USA
29. Department of Astronomy, University of Michigan, Ann Arbor, MI 48109, USA, Department of Physics, University of Michigan, Ann Arbor, MI 48109, USA
30. Instituto de Fisica Teorica UAM/CSIC, Universidad Autonoma de Madrid, E-8049 Madrid, Spain
31. Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK, Department of Physics, ETH Zurich, Wolfgang-Pauli-Strasse 16, CH-8093 Zurich, Switzerland
32. Santa Cruz Institute for Particle Physics, Santa Cruz, CA 95064, USA
33. Center for Cosmology and Astro-Particle Physics, The Ohio State University, Columbus, OH 43210, USA, Department of Physics, The Ohio State University, Columbus, OH 43210, USA
34. Center for Astrophysics, Harvard and Smithsonian, 60 Garden Street, MS 42, Cambridge, MA 02138, USA
35. Australian Astronomical Optics, Macquarie University, North Ryde, NSW 2113, Australia
36. Laboratório Interinstitucional de e-Astronomia - LIneA, Rua Gal. José Cristino 77, Rio de Janeiro RJ - 20921-400, Brazil, Departamento de Física Matemática, Instituto de Física, Universidade de São Paulo, CP 66318, São Paulo, SP 05314-970, Brazil
37. George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, and Department of Physics and Astronomy, Texas A&M University, College Station, TX 77843, USA
38. Department of Astrophysical Sciences, Princeton University, Peyton Hall, Princeton, NJ 08544, USA
39. School of Physics and Astronomy, University of Southampton, Southampton SO17 1BJ, UK
40. Physics Department, Brandeis University, 415 South Street, Waltham, MA 02453, USA
41. Laboratório Interinstitucional de e-Astronomia - LIneA, Rua Gal. José Cristino 77, Rio de Janeiro RJ - 20921-400, Brazil, Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, 13083-859 Campinas, SP, Brazil
42. Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
43. National Center for Supercomputing Applications, 1205 West Clark St., Urbana, IL 61801, USA
44. Department of Physics, University of Michigan, Ann Arbor, MI 48109, USA
45. Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL 60439, USA

ABSTRACT Wide-field imaging surveys such as the Dark Energy Survey (DES) rely on coarse measurements of spectral energy distributions in a few filters to estimate the redshift distribution of source galaxies. In this regime, sample variance, shot noise, and selection effects limit the attainable accuracy of redshift calibration and thus of cosmological constraints. We present a new method to combine wide-field, few-filter measurements with catalogues from deep fields with additional filters and sufficiently low photometric noise to break degeneracies in photometric redshifts. The multiband deep field is used as an intermediary between wide-field observations and accurate redshifts, greatly reducing sample variance, shot noise, and selection effects. Our implementation of the method uses self-organizing maps to group galaxies into phenotypes based on their observed fluxes, and is tested using a mock DES catalogue created from N-body simulations. It yields a typical uncertainty on the mean redshift in each of five tomographic bins for an idealized simulation of the DES Year 3 weak-lensing tomographic analysis of σΔz = 0.007, which is a 60 per cent improvement compared to the Year 1 analysis. Although the implementation of the method is tailored to DES, its formalism can be applied to other large photometric surveys with a similar observing strategy.

• Research Organization: SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States); Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Science (SC), High Energy Physics (HEP); USDOE Office of Science (SC), Advanced Scientific Computing Research (ASCR)
• Contributing Organization: DES; DES Collaboration
• Grant/Contract Number: AC02-76SF00515; AC02-07CH11359; AC05-00OR22725
• OSTI ID: 1558844
• Alternate ID(s): OSTI ID: 1527430; OSTI ID: 1559590; OSTI ID: 1569038
• Report Number(s): arXiv:1901.05005; FERMILAB-PUB-19-011-AE
• Journal Information: Monthly Notices of the Royal Astronomical Society, Journal Name: Monthly Notices of the Royal Astronomical Society Vol. 489 Journal Issue: 1; ISSN 0035-8711
• Publisher: Royal Astronomical Society
• Country of Publication: United Kingdom
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
gravitational lensing: weak
galaxies: distances and redshifts
dark energy
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
cosmology
photometric redshifts
weak gravitational lensing