Graduate Data on galaxy rotation curves vs visible matter

[bakerjay]

TL;DR

I'm after some raw data (visible mass vs total mass within different radii) for testing theories of dark matter in galaxies.

I'm after some raw data for testing theories of dark matter in galaxies.

Basically what I want is table showing visible mass vs total mass within different radii (or, observed rotational velocity vs expected rotational velocity without dark matter). Plus error percentages. And ideally, for multiple different galaxies.

I've been able to find lots of low-res graphs such as this, which show the sort of data I'm after, but can't seem to find it in table form...

 

[strangerep]

TL;DR Summary: I'm after some raw data (visible mass vs total mass within different radii) for testing theories of dark matter in galaxies.

I guess you have not yet found Stacy McGaugh's website and the extensive, high quality "SPARC" database, together with his data pages?

Prof McGaugh and colleagues have already done vast amounts of that kind of attempted DM fitting, eventually leading himself into deep disappointment about DM. If you can adopt a truly unbiased scientific approach, you would profit by familiarizing yourself with their work over the past 20+ yrs.

 

[bakerjay]

I guess you have not yet found Stacy McGaugh's website and the extensive, high quality "SPARC" database, together with his data pages?

Prof McGaugh and colleagues have already done vast amounts of that kind of attempted DM fitting, eventually leading himself into deep disappointment about DM. If you can adopt a truly unbiased scientific approach, you would profit by familiarizing yourself with their work over the past 20+ yrs.

Oh great, thanks! That looks like the kind of thing I'm after.

I'm having a bit of trouble interpreting some of that - for instance, in the 'Newtonian Mass Models' data, there is observed velocity, and then velocity contributions from gas, and from disk. I would have anticipated that {observed - gas - disk} would give you the velocity contribution from dark matter, but often the gas+disk contributions are actually greater than the observed velocity. What am I missing here?

 

[strangerep]

Alas, I'm not an expert, and you didn't quote the data examples that you're puzzled about.

So I'll just note that, at low accelerations, one finds that $\,g_{obs} \propto \sqrt{g_{bar}}$ .

For more detail, try these papers:

One Law to Rule them All: the Radial Acceleration Relation of Galaxies

The Radial Acceleration Relation in Rotationally Supported Galaxies

You might also benefit by following McGaugh's blog Triton Station, and also reading some of his older blog posts therein.

If you reply quickly to any of his (new) blog posts, and ask questions, sometimes he (or another poster) will answer helpfully, even if your question is not quite on the topic of his post.