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[Music]

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and I'm gonna start talking to you a

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little bit about irradiated brown dwarfs

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with my favorite quote about them which

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is actually useful which is from Adam

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Sherman and told us they are ready to

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brown dwarfs filled as crucial fourth

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corner extra matter space between

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isolated brown dwarfs who are down here

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at the bottom with high interior heat

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flux and low external irradiation

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irradiated exoplanets who are the

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reverse even low interior heat high

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external heat solar system planets here

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at the bottom with low interior and

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external heat and my relative and will

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sit up here so they sort of fit nicely

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within the zoom of planets and brown

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dwarfs and give us some idea of how we

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can look at all of them and how they all

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fits together now the problem with a

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radiative brown dwarfs in general is

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that there are not many of them known

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due to the brown dwarf desert though

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brown dwarfs in closed orbits are our

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main sequence stars there are about 19

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or 20 known today and irritatingly they

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have more problems than observing hot

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Jupiters because they have higher masses

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higher gravities lower scale height so

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you can perform transmission

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spectroscopy on them which is a little

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bit annoying what we can do however is

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observe these systems in their evolved

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forms so we take the main sequence star

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and we let it evolves it becomes a giant

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the envelope encompasses the brown dwarf

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which begins to spiral in and provided

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it doesn't die a horrible fiery death on

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the current star we're left with once

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the envelopes been rejected a white

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dwarf brown dwarf system so the brown

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dwarf obits the white dwarf with a

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period of a few hours down to the lowest

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periods we have about sixty eight

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minutes and there are nine or ten of

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these nouns so fewer than R and also a

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main sequence stars but because they all

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be a white dwarf we have the massive

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benefit that we can actually directly

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observe them so white dwarfs as you all

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know are small they're earth sized and

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they primarily emit in the UV and the

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optical

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and when we get to the infrared you can

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begin to see an infra rex s is due to

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the brown dwarf so this is a Gina

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spectrum of an odd yet unpublished

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system which is appears to be an l5

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brown dwarf orbiting at 10,000 Kelvin

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white dwarf compared to about two hours

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and the nice thing about these is we can

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subtract the white dwarf spectra off

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white dwarfs conversely to brown dwarfs

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and exoplanets are relatively simple to

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model and we can subtract wiped off

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models and get left with the brown dwarf

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spectrum and then we can analyze an

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isolated brown dwarf so look at gravity

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sensitive indices look at other

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indicators or gravity metallicity

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exactly try and determine if the brand

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off is inflated due to the heat from the

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white dwarf well we can also do with

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spectra is we can try and determine

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what's going on there and off atmosphere

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due to emission lines so if the brown

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dwarf is significantly heated and we

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have about three or four of these that

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are at the moment then we get HL 4

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emission so in this case is your dark

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line is the trail of the hydrogen line

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this is the a child for absorption

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feature and this crazy line here is your

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HL 4 emission feature this is the night

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side of burned wall and this is the day

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side of the mantle you can see we have

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two or three where this is possible to

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determine so WD lon 3/7 is the best

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known of these systems it's 114 minute

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period and it's a brown dwarf orbiting a

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the katene a half thousand Kelvin white

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dwarf

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these two are in 70ish minute orbits

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around 25,000 kelvin white dwarfs

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certainly they're moving exactly fast

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around something that's very very hot

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and as you might expect if we look at

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the rest of the spectra if we have it

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then we get all sorts of other emission

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lines now the thing i think is

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particularly interesting about this is

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when we came to look at other emission

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lines and trying to determine what's

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going on in the Brandel atmosphere

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it became quite clear that we were not

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getting the same emission features from

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all the brown dwarfs and it was not the

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most irradiated brown dwarf that was

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giving us the most emission features

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which came as a little bit of a surprise

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to me though WD 137

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well known object has all of these

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species in it this is an LA to office at

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the end of the alta T transition

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sequence white dwarf 16 1/2 thousand

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Kelvin thousand 14 minute period this

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object with the crazy name only has

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these emission features but both sets of

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actuator spectral we're not missing any

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sort of emission features here due to

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wavelength coverage it's orbiting a much

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hotter white dwarf in a much shorter

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period we see much less stuff the main

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difference is the spectral type of the

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brand wars so in an epoch in telephone

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number here it's an l-3 dwarf it's much

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more cloudy than the l8 where the clouds

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have started to disperse in some way so

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this I found quite interesting those you

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who study clouds may not found that as

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sort of knew as I did but we then found

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that of the tan white dwarf and albino

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is known there are only three there are

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eclipsing and this guy was the options

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particularly infrared to actually

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directly detect the dark side of the

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brown dwarf

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these things tightly not and there are

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about xx ish magnitude in the HM the

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cave and so they are detectable compared

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to extra points where this Germany isn't

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the case and I apologize for the

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slightly ratty data our Hawkeye time was

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not taking as good as conditions we'd

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like but what we ended up with

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essentially our brightness temperatures

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based on the night side these are the

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maximum the minimum day and night side

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temperatures the average day night so

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temperatures have a difference of about

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100 Kelvin for this object however when

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we compare that to you

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effective temperatures for the day in

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the night side we come out with sort of

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temperatures of about thirty thousand

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fourteen thousand Kelvin

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now the subject in particular CSS 1411

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should be the brown dwarf should be a

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tea Dorf we have good masses from where

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your velocity z' we have eclipses that

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we know it's radius it's not

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particularly young there's nothing

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particularly weird about it and it

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should have an effective temperature of

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about 800 Kelvin now looking at our

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light curve modeling and all the other

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information we've got there's no way we

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can bump that temperature up to 1300

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Kelvin by simply pouring in here on the

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day side I like have models as I'm sure

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most of your like live models have since

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of absorb parameter that deals with the

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amount of flux that comes in and whether

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it gets me irradiated or circulates

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around the object and this is our 8090

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percent CG in the cab and so we

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physically can't stick anymore he don't

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suspend or heat it up to this

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temperature so we were left wondering

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what on earth might be going on and our

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suggestion was perhaps that what we see

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is effectively a said nicely temperature

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isn't a temperature it's that we have an

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artificial flux sort of boosting if you

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like due to the UVA radiation from the

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white dwarf so we've got some sort of

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photochemistry going on here whether

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it's something like

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hc+ whether it's HT for essence maybe

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it's something we haven't heard of we're

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not sure but we think this might be

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happening frustratingly this object is

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towards the faint end of what we can do

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is they're getting spectra of it and

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they in the infrared isn't really

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possible at 19th Agnes you this is

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difficult for us it's a James Webb wait

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but the results we get are similar to

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what we got for W do 1 through 7 so this

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isn't eclipsing but we have extremely

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good light curves in about five wave

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fans and we can subtract the white dwarf

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contribution my gloss don't vary in

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general so we can subtract the white

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dwarf contribution and calculate the day

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of the night side temperature from the

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reflection effect that we see and using

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Jonathan for tonie's models here for a

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radiative brown dwarfs we found our best

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fitting model is the black line at the

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bottom

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to the dayside points which are these

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solid points the Nightside points of the

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big squares down at the bottom here and

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the model fit quite well to the data the

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model has circulation all the way around

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the brown dwarf and it didn't have a IO

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in it which was something we were

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looking at at the time however you can

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see these two points here this at the

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cabe and this it's four point five

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micron again these are the points here

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are too bright compared to what they

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should be for the model and again if you

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were going to look for something like HD

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plus or a steeped resonance these are

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the way fans where you would expect to

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see it so again we're left with the

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suggestion that the UV from the white

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dwarf is causing some sort of glow or

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boosting within these wave mounts and

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this is this is my great question at the

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moment and unfortunately I'm left

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waiting for spectra four point five

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microns which is James Webb and so we

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can actually try and determine what's

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going on here okay so that's sort of my

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my plug for irradiated brown dwarfs of

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why they're interesting how do they fit

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in with exoplanets so this is a figure I

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have reproduced from the work of Comet

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check at AU and I apologize if I've

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mispronounced your name there so these

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are a bunch of no exoplanets with

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equilibrium temperature versus this

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eight absorbed parameter which is the

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black assumption the day- the ninth

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divided by the de daytime practice

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temperature and you can see that

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actually has 14 11 the eclipsing system

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it's quite nicely down here almost on a

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nice straight line with everything else

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W do 137 is sort of almost on a line

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below somewhere hanging out with happy

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70 which is everybody's other favourite

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weirdo X upon M so I I've shown this

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because I think it's interesting to show

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you that these brown dwarfs are not that

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different from extra finance despite the

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fact

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that they have higher masses and

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slightly different radii I'm curious if

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you have exchanges when we have better

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data smaller error balls and more points

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on here I'm and hopefully more brown

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dwarfs on here as well thank you

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okay so I'm going to finish up talking

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about the mass radius relation for these

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objects so this is the irradiated mass

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radius relationship radio - brown dwarf

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mass radius relationship so mass on the

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bottom Brown will raise on the side and

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these are all the known irradiated brown

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00:11:52,460 --> 00:11:50,010
dwarfs around main sequence stars and

276
00:11:55,520 --> 00:11:52,470
the two where we have actual measured

277
00:11:58,040 --> 00:11:55,530
radii around white dwarfs so the two

278
00:12:00,830 --> 00:11:58,050
white dwarf ones are here interestingly

279
00:12:03,110 --> 00:12:00,840
enough they sit within the so-called

280
00:12:05,930 --> 00:12:03,120
mass gap for these brown dwarfs around

281
00:12:08,290 --> 00:12:05,940
the main sequence stars and in fact most

282
00:12:14,140 --> 00:12:08,300
of the brown dwarfs around white dwarfs

283
00:12:18,920 --> 00:12:16,850
this perhaps isn't massively surprising

284
00:12:21,380 --> 00:12:18,930
because if we're looking for them we're

285
00:12:25,010 --> 00:12:21,390
looking for brand offs around white

286
00:12:26,600 --> 00:12:25,020
dwarfs in general then if they are

287
00:12:28,070 --> 00:12:26,610
brighter in the infrared

288
00:12:29,390 --> 00:12:28,080
they are easier for us to see which

289
00:12:33,410 --> 00:12:29,400
tends to mean there's a higher mass

290
00:12:35,930 --> 00:12:33,420
earlier special type objects okay so the

291
00:12:37,460 --> 00:12:35,940
other thing that's quite interesting to

292
00:12:40,520 --> 00:12:37,470
look at this so we've got these are the

293
00:12:44,180 --> 00:12:40,530
model it's about barracks models so 100

294
00:12:46,520 --> 00:12:44,190
million years one big year five years

295
00:12:48,950 --> 00:12:46,530
and ten good years at the bottom and

296
00:12:50,630 --> 00:12:48,960
brown dwarfs all tend to about the same

297
00:12:54,140 --> 00:12:50,640
radius as they age they cool as they

298
00:12:56,540 --> 00:12:54,150
also generate objects so these objects

299
00:12:58,250 --> 00:12:56,550
would be what a brand will person would

300
00:13:01,430 --> 00:12:58,260
sort of refer to as having feel to

301
00:13:03,470 --> 00:13:01,440
gravity in general none of the stars

302
00:13:05,300 --> 00:13:03,480
these plants are around are regarded as

303
00:13:08,180 --> 00:13:05,310
young because it me not 100 million

304
00:13:10,490 --> 00:13:08,190
years old so these are the inflated

305
00:13:13,220 --> 00:13:10,500
objects I believe that one there is Cal

306
00:13:15,950 --> 00:13:13,230
plumby and pretty much everything else

307
00:13:17,000 --> 00:13:15,960
isn't inflated these two might be but

308
00:13:19,160 --> 00:13:17,010
they have working great error bars

309
00:13:21,920 --> 00:13:19,170
they're Koro objects and hopefully I

310
00:13:23,930 --> 00:13:21,930
guess path is going to provide more

311
00:13:26,000 --> 00:13:23,940
information on these and hopefully

312
00:13:29,000 --> 00:13:26,010
better early I constraints there

313
00:13:32,980 --> 00:13:29,010
interestingly that also active the two

314
00:13:35,120 --> 00:13:32,990
of the only active hosts on this figure

315
00:13:37,070 --> 00:13:35,130
but the other thing you'll notice is

316
00:13:38,840 --> 00:13:37,080
that basically the things that are

317
00:13:41,930 --> 00:13:38,850
inflated as a low-mass objects they're

318
00:13:43,760 --> 00:13:41,940
not the higher mass objects okay so how

319
00:13:47,510 --> 00:13:43,770
does this work out when you actually

320
00:13:50,980 --> 00:13:47,520
think about the orbits the host star

321
00:13:53,990 --> 00:13:50,990
temperature how does that help if at all

322
00:13:57,490 --> 00:13:54,000
okay so bear with me on my delightfully

323
00:14:00,470 --> 00:13:57,500
coloured figure here so the color

324
00:14:02,960 --> 00:14:00,480
hopefully you can see it refers to the

325
00:14:05,660 --> 00:14:02,970
temperature of the host star the small

326
00:14:08,420 --> 00:14:05,670
red dots in general are the M dwarfs the

327
00:14:11,660 --> 00:14:08,430
big blue ones are the white dwarfs and

328
00:14:13,610 --> 00:14:11,670
the size of the dot is proportional to

329
00:14:15,380 --> 00:14:13,620
the amount of flux the brown dwarf is

330
00:14:17,120 --> 00:14:15,390
receiving at the surface so this takes

331
00:14:19,550 --> 00:14:17,130
into account the size of the host star

332
00:14:23,780 --> 00:14:19,560
the temperature of the host star and the

333
00:14:26,120 --> 00:14:23,790
period so looking at this you can see

334
00:14:27,470 --> 00:14:26,130
that there are there's quite a few here

335
00:14:29,810 --> 00:14:27,480
that are getting a fair amount of

336
00:14:31,460 --> 00:14:29,820
irradiation but this one is telling

337
00:14:34,850 --> 00:14:31,470
about the same amount and that objects

338
00:14:36,530 --> 00:14:34,860
not massively inflated object at all

339
00:14:38,840 --> 00:14:36,540
between this M dwarf well okay it's got

340
00:14:41,210 --> 00:14:38,850
a large error bars but do you believe

341
00:14:42,380 --> 00:14:41,220
that's yeah it's getting a lot less

342
00:14:45,230 --> 00:14:42,390
irradiation than everything else it's

343
00:14:47,000 --> 00:14:45,240
not inflated this brown dwarf orbiting

344
00:14:49,940 --> 00:14:47,010
the white dwarf is getting a huge amount

345
00:14:53,180 --> 00:14:49,950
of irradiation and it's not inflated so

346
00:14:55,220 --> 00:14:53,190
it appears to me looking at this and I'm

347
00:14:57,890 --> 00:14:55,230
willing to be corrected and take input

348
00:14:59,270 --> 00:14:57,900
from people on this that the dominant

349
00:15:00,500 --> 00:14:59,280
factor as to whether you can inflate

350
00:15:02,600 --> 00:15:00,510
your brown dwarf orbiting a main

351
00:15:04,010 --> 00:15:02,610
sequence star is simply the mass of the

352
00:15:06,440 --> 00:15:04,020
brown dwarf it doesn't appear to be

353
00:15:08,330 --> 00:15:06,450
hugely correlated to the amount of

354
00:15:10,160 --> 00:15:08,340
irradiation you're pumping into that

355
00:15:13,580 --> 00:15:10,170
brown dwarf it's to do with the mass the

356
00:15:15,440 --> 00:15:13,590
burned off itself okay so I'm going to

357
00:15:17,950 --> 00:15:15,450
finish up here and hopefully I've

358
00:15:21,080 --> 00:15:17,960
convinced you we can directly observe

359
00:15:23,270 --> 00:15:21,090
aronia to runoff atmospheres and that

360
00:15:25,100 --> 00:15:23,280
from admittedly the two objects were

361
00:15:26,660 --> 00:15:25,110
looking at at the moment that doesn't

362
00:15:29,150 --> 00:15:26,670
appear to be a clear link between more

363
00:15:31,730 --> 00:15:29,160
UVA radiation and more emission features

364
00:15:34,700 --> 00:15:31,740
in the brand or Fatma sphere and that a

365
00:15:35,930 --> 00:15:34,710
hotter shorter period doesn't equate

366
00:15:38,300 --> 00:15:35,940
more emission lines in the ground or

367
00:15:39,650 --> 00:15:38,310
Fatma sphere and that more radiation

368
00:15:43,010 --> 00:15:39,660
doesn't necessarily indicate more

369
00:15:44,660 --> 00:15:43,020
relation the Randolph either and it does

370
00:15:46,460 --> 00:15:44,670
appear at the moment that in the two

371
00:15:47,960 --> 00:15:46,470
brand also you have data for UVA mission

372
00:15:50,210 --> 00:15:47,970
is linked to or brightening in the cabe

373
00:15:52,550 --> 00:15:50,220
and although we need more data or more

374
00:15:55,100 --> 00:15:52,560
objects admittedly it's a little tricky

375
00:15:58,160 --> 00:15:55,110
when you've only got nine before we can

376
00:16:21,620 --> 00:15:58,170
confirm this in wood detail so I will

377
00:16:22,760 --> 00:16:21,630
finish there thank you very much okay so

378
00:16:27,350 --> 00:16:22,770
I'll start with the question while we

379
00:16:30,560 --> 00:16:27,360
find the other mic so the the case where

380
00:16:32,510 --> 00:16:30,570
you were comparing the elements that we

381
00:16:34,640 --> 00:16:32,520
see in the brown dwarfs and you and you

382
00:16:37,700 --> 00:16:34,650
said that the cloudy or brown dwarfs

383
00:16:39,260 --> 00:16:37,710
show less elements is that just because

384
00:16:40,490 --> 00:16:39,270
you're masking the spectral features

385
00:16:41,870 --> 00:16:40,500
behind clouds or is it because you're

386
00:16:46,400 --> 00:16:41,880
actually sequestering those elements

387
00:16:48,800 --> 00:16:46,410
into cloud particles marvelous to be

388
00:16:50,390 --> 00:16:48,810
honest really I really don't know you

389
00:16:51,920 --> 00:16:50,400
talk to crystianna helling a lot about

390
00:16:53,720 --> 00:16:51,930
this and I know she's not here yet

391
00:16:56,450 --> 00:16:53,730
because her flight doesn't get in she

392
00:16:59,000 --> 00:16:56,460
won't be here till about 11:00 but we

393
00:17:02,600 --> 00:16:59,010
with WD 157 what we solve a whole range

394
00:17:04,310 --> 00:17:02,610
of elements we suspected there might be

395
00:17:05,990 --> 00:17:04,320
some sort of almost like a chromis fear

396
00:17:09,320 --> 00:17:06,000
and the brand off and that was what we

397
00:17:13,250 --> 00:17:09,330
were seeing for epoch two one two two

398
00:17:15,590 --> 00:17:13,260
telephone number we were less sure we

399
00:17:18,380 --> 00:17:15,600
were surprised we saw much less but it

400
00:17:19,730 --> 00:17:18,390
is a much cloudier object and I will

401
00:17:22,430 --> 00:17:19,740
admit at this point that clouds and not

402
00:17:23,960 --> 00:17:22,440
to my thing so I'm to be honest with you

403
00:17:27,320 --> 00:17:23,970
I'm not really sure there was another

404
00:17:29,960 --> 00:17:27,330
object that shows emission which is a

405
00:17:32,630 --> 00:17:29,970
later type I think it's an elf six and

406
00:17:35,990 --> 00:17:32,640
that system also shows evidence of

407
00:17:37,190 --> 00:17:36,000
having been polluted by rocky material

408
00:17:39,950 --> 00:17:37,200
so there's been some sort of planetary

409
00:17:42,350 --> 00:17:39,960
system there as well but again that

410
00:17:45,260 --> 00:17:42,360
doesn't show it doesn't even show the

411
00:17:48,320 --> 00:17:45,270
same elements as epic - hunty - it shows

412
00:17:51,680 --> 00:17:48,330
different ones so at the moment might

413
00:17:53,470 --> 00:17:51,690
yeah where I am is basically we need a

414
00:17:55,779 --> 00:17:53,480
lot more of these where

415
00:17:57,639 --> 00:17:55,789
a lot more different special types and

416
00:17:59,350 --> 00:17:57,649
levels of irradiation to really have any

417
00:18:04,360 --> 00:17:59,360
sort of idea of being able to say what's

418
00:18:05,620 --> 00:18:04,370
going on so Sarah yeah you'll alluded to

419
00:18:07,480 --> 00:18:05,630
the photochemistry and this keeps coming

420
00:18:10,649 --> 00:18:07,490
up so I just like to continue this theme

421
00:18:13,509 --> 00:18:10,659
so for the case of the the mysterious

422
00:18:14,980 --> 00:18:13,519
absent emission lines I'm just wondering

423
00:18:18,190 --> 00:18:14,990
whether the photochemistry itself would

424
00:18:20,769 --> 00:18:18,200
just drive the disappearance of the

425
00:18:22,840 --> 00:18:20,779
neutrals or the singly ionized species

426
00:18:26,049 --> 00:18:22,850
which are responsible for these sodium

427
00:18:27,460 --> 00:18:26,059
is very susceptible yeah I ins ation and

428
00:18:30,610 --> 00:18:27,470
so wouldn't surprise me if there's just

429
00:18:35,399 --> 00:18:30,620
no neutral sodium available for emission

430
00:18:37,330 --> 00:18:35,409
in the D lines and then related to that

431
00:18:39,580 --> 00:18:37,340
something perhaps you thought about I

432
00:18:42,129 --> 00:18:39,590
haven't even wrap my head around this

433
00:18:44,950 --> 00:18:42,139
yet dissociation of actually some of the

434
00:18:47,950 --> 00:18:44,960
molecules responsible for opacity in

435
00:18:50,590 --> 00:18:47,960
these objects in addition to the issues

436
00:18:55,029 --> 00:18:50,600
of clouds so the the titanium vanadium

437
00:18:57,519 --> 00:18:55,039
oxides will ionize at some point and I

438
00:18:59,830 --> 00:18:57,529
wonder if that could somehow modulate

439
00:19:02,590 --> 00:18:59,840
the temperature structure and the

440
00:19:04,690 --> 00:19:02,600
thermal budget and maybe related to

441
00:19:06,940 --> 00:19:04,700
something you've seen in the KP out of

442
00:19:10,180 --> 00:19:06,950
mission yeah so that was something we

443
00:19:12,879 --> 00:19:10,190
looked into a little bit with wgo a 137

444
00:19:14,649 --> 00:19:12,889
particularly the Tattaglia mach side his

445
00:19:16,360 --> 00:19:14,659
warming up when we originally looked at

446
00:19:19,539 --> 00:19:16,370
the dayside nights our temperatures we

447
00:19:21,610 --> 00:19:19,549
sort of went okay is this is it's a

448
00:19:23,019 --> 00:19:21,620
temperature inversion this is what

449
00:19:25,600 --> 00:19:23,029
everybody has been saying should happen

450
00:19:27,310 --> 00:19:25,610
in exoplanets and then we sort of looked

451
00:19:28,779 --> 00:19:27,320
at it a little bit more detail we looked

452
00:19:30,639 --> 00:19:28,789
at the models we looked at the

453
00:19:33,129 --> 00:19:30,649
temperature pressure scale heights from

454
00:19:35,110 --> 00:19:33,139
jonathan and marks models and we sort of

455
00:19:37,240 --> 00:19:35,120
came to the conclusion that that really

456
00:19:40,480 --> 00:19:37,250
wasn't likely to be the case for this

457
00:19:43,450 --> 00:19:40,490
object here and that photochemistry was

458
00:19:45,310 --> 00:19:43,460
possibly the most likely thing that's

459
00:19:47,470 --> 00:19:45,320
going on I mean ideally we need face

460
00:19:48,970 --> 00:19:47,480
with all spectroscopy in the cave and at

461
00:19:51,730 --> 00:19:48,980
three point six and four point five

462
00:19:55,720 --> 00:19:51,740
microns but even at you know with a

463
00:19:58,720 --> 00:19:55,730
two-hour period and that objects 15th

464
00:20:01,149 --> 00:19:58,730
magnitude that's still really tough to

465
00:20:02,740 --> 00:20:01,159
get short enough cadence in your

466
00:20:04,659 --> 00:20:02,750
spectroscopy in the infrared to actually

467
00:20:08,840 --> 00:20:04,669
get something sensible out of there it's

468
00:20:15,260 --> 00:20:12,410
hi Sara nice a I'm this may be a naive

469
00:20:16,580 --> 00:20:15,270
question and but do you consider it's

470
00:20:18,590 --> 00:20:16,590
impossible to have a reflected light

471
00:20:23,030 --> 00:20:18,600
from these objects and does that add to

472
00:20:26,750 --> 00:20:23,040
your anomalously deep so and I'm willing

473
00:20:29,390 --> 00:20:26,760
to be corrected but when I talk when I

474
00:20:34,610 --> 00:20:29,400
talk to people over the horrible static

475
00:20:36,290 --> 00:20:34,620
that I'm currently the suggestion has

476
00:20:39,590 --> 00:20:36,300
been that the reflection like mainly is

477
00:20:44,030 --> 00:20:39,600
going to show up in the optical and I

478
00:20:45,980 --> 00:20:44,040
have sent my like curve 2wd r17 to mark

479
00:20:47,600 --> 00:20:45,990
Molly at some point last summer and he

480
00:20:49,570 --> 00:20:47,610
was going to have something look look at

481
00:20:52,010 --> 00:20:49,580
that in particularly to look at the

482
00:20:53,720 --> 00:20:52,020
reflected light reflected light from

483
00:20:55,160 --> 00:20:53,730
clouds there anything whether anything

484
00:20:58,280 --> 00:20:55,170
like that's going on so these things

485
00:21:01,610 --> 00:20:58,290
vary at the 1 to 3 percent level in the

486
00:21:04,060 --> 00:21:01,620
optical and it's almost 30 ish percent

487
00:21:05,930 --> 00:21:04,070
by the time you get to the cave and okay

488
00:21:10,580 --> 00:21:05,940
I'm not sure that answered you

489
00:21:19,790 --> 00:21:10,590
necessarily okay actually I would ask a

490
00:21:21,169 --> 00:21:19,800
question so I was interested in the

491
00:21:23,210 --> 00:21:21,179
dayside night side and we have a

492
00:21:25,790 --> 00:21:23,220
contrast putt so a parameter that's

493
00:21:28,970 --> 00:21:25,800
relevant for irradiated groundworks

494
00:21:31,190 --> 00:21:28,980
that's not so much an issue for for hot

495
00:21:34,160 --> 00:21:31,200
Jupiters is the ratio of the flux coming

496
00:21:35,810 --> 00:21:34,170
out of the interior to the illumination

497
00:21:37,549 --> 00:21:35,820
that is just right what extent can you

498
00:21:39,470 --> 00:21:37,559
estimate the flux coming out of the

499
00:21:41,419 --> 00:21:39,480
interior from the age from the

500
00:21:44,590 --> 00:21:41,429
equilibrium temperature we do we just

501
00:21:47,510 --> 00:21:44,600
not know that I have no idea but I might

502
00:21:51,760 --> 00:21:47,520
pick on Jonathan and see if Jonathan

503
00:21:56,270 --> 00:21:54,169
mean I don't know off the top of my head

504
00:21:57,980 --> 00:21:56,280
but yeah if we have a mass and a decent

505
00:22:03,860 --> 00:21:57,990
age then you should be able to constrain

506
00:22:23,940 --> 00:22:03,870
the flux from interior pretty well not

507
00:22:36,970 --> 00:22:32,890
yeah yeah so you could you could if we

508
00:22:41,680 --> 00:22:36,980
take the the spectral type at face value

509
00:22:44,230 --> 00:22:41,690
if you like and use albedo etc for non

510
00:22:47,560 --> 00:22:44,240
aeration systems then yeah I guess you

511
00:22:53,380 --> 00:22:47,570
could you for work about food look into

512
00:22:55,430 --> 00:22:53,390
it I will have a think about that thanks