SITCOMTN-154: Initial studies of photometric redshifts with LSSTComCam from DP1

Charles, Eric; Crenshaw, John Franklin; Zhang, Tianqing; Schmidt, Samuel J.; Adari, Prakruth; Cohen-Tanugi, Johann; Graham, Melissa L.; Gschwend, Julia; Kalmbach, J. Bryce; Kannawadi, Arun; Malz, Alex I.; Mau, Sidney; Sevilla-Noarbe, Ignacio; Solomon, Rance; Taranu, Dan S.

doi:10.71929/rubin/2571480

Title: SITCOMTN-154: Initial studies of photometric redshifts with LSSTComCam from DP1

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Abstract

This technote holds reports based on the first analyses of the Data Preview 1 (DP1) data by the Science Unit for photometric redshifts. Although photometric redshifts are not an official DP1 data product, the "Photo-z Science Unit" generated photo-z estimates for every galaxy in DP1 using the available multi-band imaging on a best-effort basis. This work included developing training and test datasets by matching DP1 data to high-quality reference redshifts obtained with spectroscopy, Grism data, and multi-band photometry. The Science Unit used the RAIL software package to make photometric redshift estimates using eight different algorithms, developed simple scientific performance metrics, used those metrics to explore how the performance of the algorithms varied with configuration changes, derived more optimized configurations of the algorithms and tested the performance of those configurations. This work, the resulting data products and expected data distribution mechanism are all described there.

Authors:

;

SLAC National Accelerator Laboratory; Kavli Institute for Particle Astrophysics and Cosmology, SLAC National Accelerator Laboratory
Institute for Data-intensive Research in Astrophysics and Cosmology, University of Washington
Department of Physics and Astronomy, University of Pittsburgh
Department of Physics & Astronomy, University of California, Davis
Department of Physics and Astronomy, Stony Brook University
Université Clermont-Auvergne, CNRS/IN2P3, LPCA
Dept. of Astronomy, University of Washington; Institute for Data-intensive Research in Astrophysics and Cosmology, University of Washington
Laboratorio Interinstitucional de e-Astronomia
SLAC National Accelerator Laboratory
Department of Physics, Duke University; Department of Astrophysical Sciences, Princeton University
McWilliams Center for Cosmology & Astrophysics, Department of Physics, Carnegie Mellon University
Department of Physics, Duke University
Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas
Université Savoie Mont-Blanc, CNRS/IN2P3, LAPP
Department of Astrophysical Sciences, Princeton University

Publication Date:: Mon Jun 23 04:00:00 UTC 2025

Other Number(s):: Vera C. Rubin Observatory Commissioning Technical Note SITCOMTN-154

DOE Contract Number:: AC02-76SF00515

Research Org.:: NSF-DOE Vera C. Rubin Observatory

Sponsoring Org.:: U.S. National Science Foundation; U.S. Department of Energy Office of Science

Subject:: 79 ASTRONOMY AND ASTROPHYSICS

OSTI Identifier:: 2571480

DOI:: https://doi.org/10.71929/rubin/2571480

Citation Formats


                    Charles, Eric, Crenshaw, John Franklin, Zhang, Tianqing, Schmidt, Samuel J., Adari, Prakruth, Cohen-Tanugi, Johann, Graham, Melissa L., Gschwend, Julia, Kalmbach, J. Bryce, Kannawadi, Arun, Malz, Alex I., Mau, Sidney, Sevilla-Noarbe, Ignacio, Solomon, Rance, and Taranu, Dan S. SITCOMTN-154: Initial studies of photometric redshifts with LSSTComCam from DP1.  United States: N. p., 2025. 
        Web.  doi:10.71929/rubin/2571480.

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                    Charles, Eric, Crenshaw, John Franklin, Zhang, Tianqing, Schmidt, Samuel J., Adari, Prakruth, Cohen-Tanugi, Johann, Graham, Melissa L., Gschwend, Julia, Kalmbach, J. Bryce, Kannawadi, Arun, Malz, Alex I., Mau, Sidney, Sevilla-Noarbe, Ignacio, Solomon, Rance, & Taranu, Dan S. SITCOMTN-154: Initial studies of photometric redshifts with LSSTComCam from DP1.  United States.  doi:https://doi.org/10.71929/rubin/2571480

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                    Charles, Eric, Crenshaw, John Franklin, Zhang, Tianqing, Schmidt, Samuel J., Adari, Prakruth, Cohen-Tanugi, Johann, Graham, Melissa L., Gschwend, Julia, Kalmbach, J. Bryce, Kannawadi, Arun, Malz, Alex I., Mau, Sidney, Sevilla-Noarbe, Ignacio, Solomon, Rance, and Taranu, Dan S. 2025.  
"SITCOMTN-154: Initial studies of photometric redshifts with LSSTComCam from DP1".  United States.  doi:https://doi.org/10.71929/rubin/2571480.  https://www.osti.gov/servlets/purl/2571480. Pub date:Mon Jun 23 04:00:00 UTC 2025

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@article{osti_2571480,

  title        = {SITCOMTN-154: Initial studies of photometric redshifts with LSSTComCam from DP1},

  author       = {Charles, Eric and Crenshaw, John Franklin and Zhang, Tianqing and Schmidt, Samuel J. and Adari, Prakruth and Cohen-Tanugi, Johann and Graham, Melissa L. and Gschwend, Julia and Kalmbach, J. Bryce and Kannawadi, Arun and Malz, Alex I. and Mau, Sidney and Sevilla-Noarbe, Ignacio and Solomon, Rance and Taranu, Dan S.},

  abstractNote = {This technote holds reports based on the first analyses of the Data Preview 1 (DP1) data by the Science Unit for photometric redshifts. Although photometric redshifts are not an official DP1 data product, the "Photo-z Science Unit" generated photo-z estimates for every galaxy in DP1 using the available multi-band imaging on a best-effort basis. This work included developing training and test datasets by matching DP1 data to high-quality reference redshifts obtained with spectroscopy, Grism data, and multi-band photometry. The Science Unit used the RAIL software package to make photometric redshift estimates using eight different algorithms, developed simple scientific performance metrics, used those metrics to explore how the performance of the algorithms varied with configuration changes, derived more optimized configurations of the algorithms and tested the performance of those configurations. This work, the resulting data products and expected data distribution mechanism are all described there.},

  doi          = {10.71929/rubin/2571480},

  journal      = {},

  number       = ,

  volume       = ,

  place        = {United States},

  year         = {Mon Jun 23 04:00:00 UTC 2025},

  month        = {Mon Jun 23 04:00:00 UTC 2025}

}

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DOI: https://doi.org/10.71929/rubin/2571480

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