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Stellar/planet properties and confirmation of some K2 planets
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Dilution, Stellar Parameters, and MCMC #11

Closed dfm closed 9 years ago

dfm commented 9 years ago

I've been hacking on trying to include dilution effects into the planet parameters and I don't think that I can do it without resampling the posteriors conditioned on this model. I'm coming around to the opinion that maybe it's actually just better re-run the MCMC chains when we settle on a final set of stellar parameters…

Another point: so far, I've been taking Tim's samples for the stellar parameters and approximating the distribution using a KDE. What do you guys think about just using the multivariate Gaussian instead? We're artificially inflating the errorbars anyways and it seems to me like the Gaussian would capture all the relevant structure. It would be easier to work with :-) Opinions?

timothydmorton commented 9 years ago

I'm not sure I understand your first point...are we not settled on using these stellar parameters? What else are we waiting for on that? Also maybe I'm not understanding because I'm not sure what exactly "this model" is, etc.

In any case, approximating the stellar parameters as a multivariate Gaussian sounds reasonable to me!

benmontet commented 9 years ago

Yeah, I'm happy with these stellar parameters also. The only thing we're missing is the dilution on those two with AO, and I'll have that for you shortly. The others shouldn't change.

I'm happy to use a Gaussian, too, but let's be clear that this is what we do. There are some with a long tail, presumably caused by having some probability of being slightly evolved, and we'll lose this when we move to a Gaussian.

On Tue, Mar 10, 2015 at 5:59 AM, timothydmorton notifications@github.com wrote:

I'm not sure I understand your first point...are we not settled on using these stellar parameters? What else are we waiting for on that? Also maybe I'm not understanding because I'm not sure what exactly "this model" is, etc.

In any case, approximating the stellar parameters as a multivariate Gaussian sounds reasonable to me!

— Reply to this email directly or view it on GitHub https://github.com/benmontet/k2-characterization/issues/11#issuecomment-78024388 .

benmontet commented 9 years ago

There's actually only one with an AO companion that matters for the photometry. This is 201828749, which is 2.0 \pm 0.1 mags fainter. This means 86 \pm 1\% of the light is coming from the primary and 14 \pm 1\% from the secondary.

benmontet commented 9 years ago

@dfm was this ever dealt with appropriately?

dfm commented 9 years ago

I have just set some code running to do this... Sorry I'd forgotten

benmontet commented 9 years ago

Status update?

dfm commented 9 years ago

Still running! I'm inclined to just update that in response to referee because I'm not sure if it'll be finished by 4...

benmontet commented 9 years ago

Okay. We'll see if we finish by 4 and will decide one way or the other based on that.

On Thu, Mar 26, 2015 at 2:53 PM, Dan Foreman-Mackey < notifications@github.com> wrote:

Still running! I'm inclined to just update that in response to referee because I'm not sure if it'll be finished by 4...

— Reply to this email directly or view it on GitHub https://github.com/benmontet/k2-characterization/issues/11#issuecomment-86669053 .