This is quite a lengthy bullet point, but I think I've made some really nice progress these last few days cleaning up the results for the environment calculations, and I believe I have all the information now to easily process/compute anything depending on the choices we want to make.

Below, there are two main sections of tables. I've also included a key below for all of the columns in the table since they're quite hefty/might not be totally obvious what each column means.

• Full Data Tables, No Cuts
  • These tables are very large and located on separate pages because this Wiki page ran out of space.
  • In these tables, I've listed all of the galaxies in the HDC and LDC for our target galaxies without any cuts. I've then cross-correlated the galaxies as they appear in the HDC/LDC with the full 2MRS catalog, which gave me acces to the proper magnitudes that we care about for our calculations. Specifically, this cross-checking between catalogs gives me the k-tc (total, extinction corrected magnitudes) for all of the HDC and LDC members. Importantly, and as we saw last time, this k-tc is different than the default 2MASS K-band magnitude listed in the HDC/LDC catalogs alone. This k-tc is also what is used by Melanie in Paper 7 for her calculations.
    • This means that we can now use a consistent set of magnitudes and distances for all of our calculations, rather than mixing the generic 2MASS K-band measurements with the total, extinction corrected measurements.
• Applying Cuts
  • I've then taken the k-tc's described above and converted those to total, extinction corrected absolute magntiudes using two different distance estimates. The first distance is the mean group distance as I've been doing these last few weeks, and the other distance is the heliocentric distance listed in the HDC/LDC catalogs which we discussed for the first time this week and are different for every galaxy. We can thus choose to make our Mk cuts on either the former or latter distance measure.
  • Thus, I've listed the results of applying the cuts to these two distance measures. To be clear:
    • Applying Cuts Based on Group Distances: the cuts in these tables are made by computing Mk = ktc - 5*log10(Group Distance) - 25
    • Applying Cuts Based on Individual Distances: the cuts in these tables are made by computing Mk = ktc - 5*log10(individual distances in HDC/LDC) - 25

With the above being said, there are a number of choices/questions we probably want to discuss but should have very minor impacts on things so far:

• Do we want to move forward using the individual distances from HDC/LDC, or do we want to use the mean group distances?
  • I think it's most self-consistent to use the individual distances from the HDC/LDC. However for the galaxies which need to use the full 2MRS catalog, all we have are the redshift distances.
• If we choose to stick to mean group distances only:
  • What do we do for a case where we need both HDC and LDC to fill out 10 neighbors? The issue here is that the mean distance quoted for the HDC is often slightly different from the LDC since they have different memberships. I think the most self-consistent choice is to flatten all galaxies to the mean distance for the HDC, and that's what I've done below where mentioned (see note about the edge case galaxy).

• Neighbor #
• Name
• RA
• Dec
• Group Distance
  • Mean group distance for the HDC/LDC in question, corrected to h=0.7
• Distance in HDC
  • Individual distances for galaxies in each HDC/LDC, corrected to h=0.7
• Separation
  • 2d separation unless otherwise specified (flattens all galaxies in a group to the same distance)
• K [HDC/LDC]
  • 2MASS K band magntiude listed in HDC/LDC directly
• Mk [HDC/LDC]
  • Mk = K [HDC] - 5log10(Group Distance) - 25
  • Absolute K band using only HDC/LDC data
• Matched K
  • Result for searching through 2MRS full catalog for matched galaxy
  • These should be the same as K [HDC/LDC] values
• Matched K_tc
  • Corresponding total, extinction corrected K magnitude listed in 2MRS
• Av
  • Av taken from Schlegel+Finkbeiner (2011)
• k_m_ext
  • Computed as K_tc + 0.11*Av
  • These should be the same values reported in Table 1 of MASSIVE I for our galaxies in question; this column is a nice sanity check
• Mk [K_tc & Group D]
  • Mk = K_tc - 5*log10(mean group distance) - 25
• Mk [K_tc & Individual D]
  • Mk = K_tc - 5*log10(individual distances) - 25

This Github wiki page became too long when I included these tables, so I moved them to their own separate pages.

These tables show the full set of members in all of the HDC/LDC groups, but I've cross-checked their entries with the entries in the full 2MRS dataset to obtain their K_tc magnitudes and individual distances.

FULL HDC Data Tables

FULL LDC Data Tables

• (a) adopt the mean group distance for each group
• (b) adopt the individual distances reported in the HDC/LDC datasets.

• Neighbors 0-6 are from HDC, rest are from LDC.
• In the table below, I've updated the LDC member group distances to be the same as the HDC distances. In turn, I've updated the separations and corresponding Mk.

With this cutting scheme, NGC7619 becomes a strange edge-case depending on which distance we choose to adopt.

To get these neighbors, we can simply take the first ten neighbors from the LDC table results.

• 8/10 neighbors come from HDC, the last 2 neighbors (UGC 12518, NGC7562) comes from LDC.
• For the galaxies which comes from LDC, since I pull the data from the full LDC data base, the Group Distance listed by default is the mean LDC distance. It would be more consistent if we re-assign this distance to the HDC mean distance. In the tables below, I do this change by hand, updating the Group Distance, 2d separation, and corresponding magnitudes for the two galaxies which come from LDC.

One very interesting thing to note for this galaxy's results:

• You'll notice in the table below that UGC12518's "Mk [K_tc & Group D]" which we are cutting on is -22.98 here, so it technically should not make the cut.
• The reason it's included below is because of the distance reassignment described above. UGC 12518 comes from LDC, and the LDC reports a slightly different mean Group Distance than the one listed in HDC. Specifically, the LDC mean group distance is 48.72 Mpc, whereas the HDC mean distance is 47.966 Mpc.
  • If you compute Mk based on the LDC distance, you get: 10.417 - 5log10(48.72) - 25 = -23.02.
  • However, when you update the LDC distance from 48.72 to 47.966, this becomes: 10.417 - 5log10(47.966) - 25 = -22.9876.
  • Again, this only "made the cut" because I had to update the two galaxies numbers by hand given the new distance; this is not a result of a bug in my code missing this cut.

I'd be totally happy to kick out UGC 12518 and find the next neighbor from the 2MRS full catalog, but kept in in this list for us to discuss.

• After finding the neighbors, I use the distance listed in 2MRS (computed as comoving distance using velocity listed in full 2MRS catalog), recompute separations relative to the group mean, and recompute Mk

• In filling out the remaining members, the nearest neighbors are actually in a nearby HDC group, so I've adopted those respective values for the galaxies.