Will there be a cluster catalog for the DP0 data set?

An great question about the DP0 data set came to me by email, which I’m reposting here so that others can help to answer it.

From Table 1 and Sections 2.4 and 2.5 of The LSST DESC DC2 Simulated Sky Survey paper, it looks like exploring the best methods of creating cluster catalogs and identifying large scale structures is a big part of the work, but will there be any sort of cluster catalog that we can work with as soon as DP0 comes out (list of cluster positions, etc.)?

I can see that Section 3.2 mentions that the Truth-match Table includes only galaxies, stars, and supernovae, and that Section 5 mentions cluster catalogs as a future “add-on” catalog. Both of these indicate that neither a Truth nor a data-derived cluster catalog are available now, but perhaps someone could confirm, deny, or provide some additional details about this topic?

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The galaxies were generated in CosmoDC2, which also provides information on the halo membership. One could construct a “truth” cluster catalog from these inputs based on some criteria for defining clusters based on halos.

CosmoDC2 is available here:
https://lsstdesc-portal.nersc.gov/doc/cosmodc2

Here’s a rendered Notebook showing an example of identifying in CosmoDC2 members of halos above a certain mass:

DESC doesn’t yet have a cluster catalog from the processed image data. We’re currently working on it internally. Once its used and validated in published scientific analyses we intend to make it publicly available.

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