FORECASTOR – II. Simulating galaxy surveys with the Cosmological Advanced Survey Telescope for Optical and UV Research

Journal Article · Fri Jan 17 00:00:00 EST 2025 · Monthly Notices of the Royal Astronomical Society

DOI:https://doi.org/10.1093/mnras/staf065· OSTI ID:2520126

Marshall, Madeline Anne ^[1]; Amen, Laurie ^[2]; Woods, Tyrone E. ^[3]; Côté, Patrick ^[4]; Yung, L. Aaron ^[5]; Amenouche, Melissa ^[4]; Pass, Emily K. ^[6]; Balogh, Michael L. ^[7]; Salim, Samir ^[8]; Moutard, Thibaud ^[9]

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1. National Research Council of Canada, Victoria, BC (Canada); Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
2. National Research Council of Canada, Victoria, BC (Canada); McGill Univ., Montreal, QC (Canada)
3. National Research Council of Canada, Victoria, BC (Canada); Univ. of Manitoba, Winnipeg, MB (Canada)
4. National Research Council of Canada, Victoria, BC (Canada)
5. NASA Goddard Space Flight Center (GSFC), Greenbelt, MD (United States); Space Telescope Science Institute, Baltimore, MD (United States)
6. Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States); Univ. of Waterloo, ON (Canada)
7. Univ. of Waterloo, ON (Canada). Waterloo Centre for Astrophysics
8. Indiana Univ., Bloomington, IN (United States)
9. European Space Agency (ESA), Madrid (Spain). European Space Astronomy Centre (ESAC); Aix-Marseille Univ., Marseille (France); Centre National de la Recherche Scientifique (CNRS) (France)

The Cosmological Advanced Survey Telescope for Optical and UV Research (CASTOR) is a planned flagship space telescope, covering the blue-optical and UV part of the spectrum. Here, we introduce the CASTOR image simulator, a python GalSim package-based script capable of generating mock CASTOR images from an input catalogue. We generate example images from the CASTOR Wide, Deep, and Ultra-Deep surveys using simulated lightcones from the Santa Cruz semi-analytic model. We make predictions for the performance of these surveys by comparing galaxies that are extracted from each image using Source Extractor to the input catalogue. We find that the Wide, Deep, and Ultra-Deep surveys will be 75 per cent complete for point sources down to $$\sim 27$$, 29, and 30 mag, respectively, in the UV, u, and g filters, with the UV-split and u-split filters reaching a shallower depth. With a large area of $$\sim 2200$$ deg$^2$, the Wide survey will detect hundreds of millions of galaxies out to $$z\sim 4$$, mostly with $$M_\ast \gtrsim 10^{9}\,{\rm M}_{\odot }$$. The Ultra-Deep survey will probe to $$z\sim 5$$, detecting galaxies with $$M_\ast \gtrsim 10^{7}{\rm M}_{\odot }$$. These galaxy samples will enable precision measurements of the distribution of star formation in the cosmic web, connecting the growth of stellar mass to the assembly of dark matter haloes over two thirds of the history of the Universe, and other core goals of CASTOR’s legacy surveys. These image simulations and the tools developed to generate them will be a vital planning tool to estimate CASTOR’s performance and iterate the telescope and survey designs prior to launch.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE Laboratory Directed Research and Development (LDRD) Program
• Grant/Contract Number: 89233218CNA000001
• OSTI ID: 2520126
• Report Number(s): LA-UR--24-32481
• Journal Information: Monthly Notices of the Royal Astronomical Society, Journal Name: Monthly Notices of the Royal Astronomical Society Journal Issue: 2 Vol. 537; ISSN 0035-8711
• Publisher: Oxford University Press
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
evolution of galaxies
simulations
software
star formation
telescopes
ultraviolet