Queries for gravity-only simulations
Our gravity-only data comprises dark matter halos and their associated profile data and, for high mass clusters, particle data. The queries we have focus on reducing the data to the set of halos that interest you and returning associated data, both on the snapshot and the lightcone frame.
Additionally we provide density maps in the lightcone frame, which can be used for weak lensing analysis. This query focuses on returning the data in chosen redshift ranges, and downgrading to a level which best fits your analysis needs.
Halo Query
This returns properties for halos in the Frontier-E gravity-only simulation for a selection of redshift snapshots. Required selections are the simulation, the redshift, an upper limit to the number of halos returned and whether or not to include density profiles of the selected halos.
You can then optionally select on mass (either FOF or M200c), R200c, or concentration. If you want a sample of well-measured SOD halos, you should include minimum bounds of c_200c > 0 and M200c > 1.34e11. This ensures that the spherical overdensity mass measurement is above the measurement threshold, and that the concentration measurement from the profile succeeded. Note that otherwise these are not guaranteed, as we return low-mass FOF halos which do not have spherical overdenisties measured.
Running a query will output preview images which should help to confirm that the data is correct, in this case we show previews of the FOF halo mass function, and the ability to download or transfer the dataset. This data can be opened with the OpenCosmo toolkit (https://opencosmo.readthedocs.io/) for further analysis.
Halo-Particles Query
This is an alternate halo query, in the case where you want to return all the particles associated with your halos. The main difference here is that as we only have particle information for high mass halos, you are limited to mass selections over log10(M) = 13.5.
As the particle information is typically quite large we also restrict the number of halos returned to a maximum number below 1000. This selection is a non-repeatable random selection of halos.
Again, the output data can be read in using the opencosmo toolkit, with particles linked to the halos as a structure collection.