Semi-Analytic Forecasts for the Universe

We provide a wide variety of scientific predictions and simulated data products that are designed to be useful for optimizing observing strategies, physically interpreting observational results, and ultimately maximizing the scientific output of galaxy surveys.

These predictions are made with the well-established Santa Cruz semi-analytic model (SAM) for galaxy formation. Taking advantage of the physically motivated and yet computationally efficient model, we provide predictions for tens of millions of galaxies across wide ranges of mass and redshift.

Over the course of seven publications, we compared the model outputs with a wide variety of observational constraints available to date, including distribution functions for rest-frame UV magnitude, stellar mass, star formation rate and a variety of scaling relations. We showed that the model reproduces constraints well up to z ~ 10. We use NASA’s flagship observatories James Webb Space Telescope (JWST) and Nancy Grace Roman Space Telescope (Roman) as practical examples to demonstrate how these predictions can be used. These results are presented in a series of publications entitled “Semi-analytic forecasts for JWST” and “Semi-analytic forecasts for Roman”.

We provide three sets of simulated lightcones:

1. a set of 40 wide-field lightcones, each spanning ~1,000 sq. arcmin with footprints overlapping the five CANDELS legacy fields, resolving galaxies down to M*~10^7 Msun
2. a set of 8 deep-field lightcones, each spanning 132 sq. arcmin with footprints overlapping the HUDF, resolving galaxies down to M*~5.7×10^7 Msun
3. a set of 5 ultra-wide lightcones, each spanning 2 sq degrees, with resolution matching the wide-field lightcones. For all three sets of catalogs, we provide observed-frame photometry for JWST (NIRCam), Roman (WFI), Hubble (WFC3/ACS), Spitzer, Euclid, Rubin, GALEX, SDSS, UKIRT, VISTA and DECam, as well as rest-frame luminosity for NUV, FUV and Johnson/Bessel/Cousins bands, and a wide variety of predicted physical properties for halos and galaxies.

Access simulated lightcones through the Flathub interactive portal Flathub.

• select galaxy samples and create simple diagnostic plots

Access simulated lightcones direct download in this directory.

• include full object catalogs and SEDs in ASCII format

Tabulated data are available in this directory.

• include distribution functions and scaling relations