Halo property requests for DC3

[aphearin]

This issue will collect requests for specific halo properties that people would like to see included in DC3. If you would like to include such a request, please comment here. Remember to be as specific and quantitative as possible, both in the definition of the requested property, and in the science motivation driving the request.

• Halo concentration - Best-fit NFW profile parameter. Critical for studies of assembly bias.
• Halo shape information - Requested by the Cluster WG to facilitate studies of cluster mass estimation errors due to correlations between scatter in intrinsic richness and projection effects. Further information needed:
  • @hywu: Exactly what is needed? Is the principal eigenvector of the inertia tensor sufficient? Or would the reduced inertia tensor be preferable? Are all three eigenvectors needed?

[hywu]

Three eigenvalues and the corresponding eigenvectors for the reduced inertia tensor would be very helpful.

[cavestruz]

From notes during DESC meeting: Extragalactic catalog needs -

1. SO Masses, M200c, c200c, etc.
2. Relaxation indicators: Virial ratio, offset between center of mass and depth of potential halo center
3. Merger trees (some discussion of how this could be accessed, and querying progenitors of halos above some mass, given z1/2, etc).... (mostly want to be able to access change in mass over some period of time and merger ratios)
4. Shape, and galaxies on top of subhalos that are correlated with large scale structure, tidal fields, etc.

Images -

1. Stronger shears in cluster fields
2. ICL