Numerical Facts about the Milky way's halo

AI Thread Summary
The discussion focuses on the challenges of determining the density, scale radius, and normal radius of the Milky Way's halo for use in the NFW profile. It highlights that the scale density is not a definitive numerical fact due to its degeneracy with the scale radius, meaning multiple pairs of values can fit the data. The conversation suggests that expressing halo profiles in terms of v_max may provide clearer insights than relying solely on rho_0. A proposed halo model with constants is shared, along with a reference to a relevant paper for further details. Overall, the complexity of halo modeling is emphasized, particularly in the context of the NFW profile.
majormuss
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I am trying to find the density, scale radius and normal radius of the milky way's halo. But these things are pretty hard to find. I want to find them so I can input them into the NFW profile:
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In this thread I gave some constants of a proposed halo model as well as a link to a paper with more detail.
 
This may be a nitpick (depending on what you are trying to achieve) but the scale density is not a "numerical fact" because it is degenerate with the scale radius when you express the NFW profile as you have done. For any set of data there is a range of pairs of values rho_0 and R_s that all fit well enough, so you can't say any particular value of rho_0 is a "fact". Its often better with these halo profiles to express them in terms of v_max instead of rho_0.
 

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