meeting 2025 11 25 gw - JacobPilawa/TriaxSchwarzschild_wiki_6 GitHub Wiki

Context

• Mostly have focused on populating the overleaf, but I did manage to track down the extinction for the K-band measurements (for the mass comparison of the K-band vs. Cluver+14 prescription).

• In short, I downloaded the SFD (2011) dust map which allows me to query for E(B-V) as a function of RA and Dec.

  • Assuming an R_V = 3.1, I computed the extinction A_V for the ~1 million galaxies in 2MPZ, and recomputed the stellar mass estimates with the extinction.
  • In short, there's virtually no change in our masses since the extinctions are quite small.

• Here's the distribution of Av values that I computed. Note that the K-band absolute magnitudes get modified by 0.11*Av (following Equation 1 from MASSIVE I):

Av Distribution
images/251125/Av_distribution.png

• And here are the updated mass comparisons:

1-to-1	Differences
[images/251125/revised_2mpz_masses_differences_with_extinction.png]]](/JacobPilawa/TriaxSchwarzschild_wiki_6/wiki/[[images/251125/revised_2mpz_masses_with_extinction_for_K_band.png)

Cappellari Mass Estimate

• Cappellari (2013) has an estimator for the stellar mass in a similar form to Emily's equation. He prefers:

M* = 10.58 - 0.44(M_K + 23)

• Compared to Emily's

M* = 11.92 - 0.49(M_K + 26)

• If I use this estimator (really just swapping out the coefficients + offset=23), I get the following:

1-to-1	Differences
[images/251125/CAPPELLARI_revised_2mpz_masses_differences_with_extinction.png]]](/JacobPilawa/TriaxSchwarzschild_wiki_6/wiki/[[images/251125/CAPPELLARI_revised_2mpz_masses_with_extinction_for_K_band.png)

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