The PAU Survey: Galaxy stellar population properties estimates with narrowband data

¹ Universität Innsbruck, Institut für Astro- und Teilchenphysik, Technikerstraße 25/8, 6020 Innsbruck, Austria
² University Observatory, Faculty of Physics, Ludwig-Maximilians-Universität, Scheinerstr. 1, 81677 Munich, Germany
³ Excellence Cluster ORIGINS, Boltzmannstr. 2, 85748 Garching, Germany
⁴ Institute of Space Sciences (ICE, CSIC), Campus UAB, Carrerde Can Magrans, 08193 Bellaterra (Barcelona), Spain
⁵ Instituto Astrofísica de Canarias, Av. Via Láctea s/n, 38205 La Laguna, Spain
⁶ Department of Astronomy, Tsinghua University, Beijing 100084, China
⁷ Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Avenida Complutense 40, 28040 Madrid (Madrid), Spain
⁸ Port d’Informació Científica (PIC), Campus UAB, C. Albareda s/n, 08193 Bellaterra (Cerdanyola del Vallés), Spain
⁹ Institució Catalana de Recerca i Estudis Avançats (ICREA), Pg. de Lluís Companys 23, 08010 Barcelona, Spain
¹⁰ Institut de Física d’Altes Energies (IFAE), The Barcelona Institute of Science and Technology, Campus UAB, 08193 Bellaterra (Barcelona), Spain
¹¹ Instituto de Fisica Teorica (UAM/CSIC), Universidad Autonoma de Madrid, 28049 Madrid, Spain
¹² Institute of Cosmology and Gravitation (University of Portsmouth), Portsmouth, UK
¹³ Institut d’Estudis Espacials de Catalunya (IEEC), Gran Capità 2-4, Ed. Nexus 201, 08034 Barcelona, Spain
¹⁴ Satlantis, University Science Park, Sede Bld, 48940 Leioa-Bilbao, Spain
¹⁵ Jockey Club Institute for Advanced Study, The Hong Kong University of Science and Technology, Hong Kong S.A.R., China
¹⁶ Institute for Computational Cosmology, Department of Physics, Durham University, South Road, Durham DH1 3LE, UK

Received: 1 March 2024
Accepted: 30 May 2024

Abstract

A newfound interest has been seen in narrowband galaxy surveys as a promising method for achieving the necessary accuracy on the photometric redshift estimate of individual galaxies for next-generation stage IV cosmological surveys. One key advantage is the ability to provide higher spectral resolution information on galaxies, which ought to allow for a more accurate and precise estimation of the stellar population properties for galaxies. However, the impact of adding narrowband photometry on the stellar population properties estimate is largely unexplored. The scope of this work is two-fold: 1) we leverage the predictive power of broadband and narrowband data to infer galaxy physical properties, such as stellar masses, ages, star formation rates, and metallicities; and 2) we evaluate the improvement of performance in estimating galaxy properties when we use narrowband instead of broadband data. In this work, we measured the stellar population properties of a sample of galaxies in the COSMOS field for which both narrowband and broadband data are available. In particular, we employed narrowband data from the Physics of the Accelerating Universe Survey (PAUS) and broadband data from the Canada France Hawaii Telescope legacy survey (CFHTLS). We used two different spectral energy distribution (SED) fitting codes to measure galaxy properties, namely, CIGALE and PROSPECTOR. We find that the increased spectral resolution of narrowband photom try does not yield a substantial improvement in terms of constraining the galaxy properties using the SED fitting. Nonetheless, we find that we are able to obtain a more diverse distribution of metallicities and dust optical depths with CIGALE when employing the narrowband data. The effect is not as prominent as expected, which we relate to the low narrowband signal-to-noise ratio (S/N) of a majority of the sampled galaxies, the respective drawbacks of both codes, and the restriction of coverage to the optical regime. The measured properties are compared to those reported in the COSMOS2020 catalogue, showing a good agreement. We have released the catalogue of measured properties in tandem with this work.