Personal shout out to my fellow #exoplaneteers who toot conferences. Being removed by a 17 hour flight from most meetings means this is how I get the download on all the crazy cool stuff you are up to! You're true champions of #DEIA #SEHR2023@bibianaprinoth

To finish my reporting from #SEHR2023, here is our karaoke list from yesterday 🎤 🎶

Given the crazy amount of ESPRESSO data for these observations (thanks #ESO ❤️) we can measure orbital parameters but also peak emission offsets. The data supports the global depletion scenario. Other species seem unaffected.

Also space + ground-based are complementary. #SEHR2023

Testing local condensation vs. global depletion!

Observations with ESPRESSO show that Ti-bearing species are also depleted from the nightside —> global depletion.

Note that because of this being emission, we are highly sensitive to the temperature. With or without TiO, the depth of e.g. Fe absorption changes, such that you need a lower temp. without TiO to match the depth. #SEHR2023

Titanium seems to be depleted, as also shown by other groups. This means this becomes a story about condensation. But where? How do condensates mix? Locally at the terminator? Or on the nightside?

To answer this, we need to look at the dayside too. #SEHR2023

Another lovely planet, my favourite one, WASP-189 b, shows differences in signal strength over the course of the transit, and a detection of TiO. If you wanna know more about this, please reach out. I am working on that ☺️

Jens’ puts out the big question: Is this the time to do retrievals?

We move on to WASP-121 b, Jens’ favourite planet. It has a long story of VO / TiO, with VO being the stronger absorber if both are present. Interestingly, the temperature drives the presence.

#SEHR2023

Nic (Jens’ PhD student) continued with the deep search of elements all over the periodic table, detecting Ba+ and Tb+. These are very heavy elements. And one may wonder what this tells us about the formation/evolution of this planet. #SEHR2023

Next up, we have Jens Hoeijmakers about “Metals and more: high-resolution spectroscopy of ultra-hot Jupiters”

Transmission spectroscopy made easy ;) My supervisor reuses my slides. Love it 😅

In contrast to colder planets, in UHJs, we actually look at atoms and ions as dominant absorbers (besides H/He of course). It doesn’t mean that they are not there, but we can look “easily” for atoms and ions.

#SEHR2023

Katy now makes a link to high-res. Here comes the HITRAN/ExoMol discussion: using the high accuracy data from HITRAN measured in the lab to push the accuracy of calculated (theoretical) #ExoMol line lists. Together with a team of high-school students (ORBYTS) she collected transitions from many publications for a molecule and pushed the accuracy. Super cool project! I love! #SEHR2023

Katy makes the link to line lists: When the data was initially analysed in 2014, the AlO line list was not updated. It got updated in 2015, so the reanalysis showed a better match. Similarly, for another planet, there is evidence for CrH obtained with an updated line list. Katy introduced the #ExoMolOP database which is suitable for low- to medium-res observations. #SEHR2023

The lines as they come out of line list calculations don’t have a shape yet, because they don’t account for pressure/temperature broadening yet. For Hot Jupiters, H/He is the dominating broadener in their atmospheres. For colder planets, this is done by (more) complex molecules. #SEHR2023

Next up we have Katy Chubb about “using a variety of molecules in exoplanet atmosphere studies” ✨

1) How do we know what the spectra of molecules look like?

We can measure their spectra in the lab, or we can calculate the spectra from quantum methods. This way we get line lists so we can calculate the cross-sections (sooooo I wish this talk would’ve been one of the first ones…)

#SEHR2023

This whole #conference is eye-opening and scares the **** out of me. I don’t feel like I understand anything anymore 😅🫣 #astrodon #SEHR2023

TiO and VO. I am scared. Apparently V has huge hyperfine structure, which is not the case for Ti. So once the hyperfine-resolved line list is out, the VO line list is expected to be more accurate and thus better to use when doing cross-correlations. At least that’s how I understood this 🫠 #SEHR2023

Okay, so I need to out down my thoughts here:

I feel like I have no chance of choosing “the right line list” as a consumer. So I am wondering: How do I decide? What is right? What is wrong? How right/wrong am I? Help? 😭

#ExoMolHD includes an uncertainty column that tells you which lines to use, and which we shouldn’t. This means we should regenerate our templates we use to do cross-correlations with. Noted.

#SEHR2023

Next up, we have Jonathan Tennyson on the “Use of the #ExoMol database of high accuracy spectroscopy of exoplanets”

To my understanding, one of the major differences between ExoMol and HITRAN/HITEMP is that ExoMol is purely computational, while HITRAN/HITEMP is empirical. Correct me if I am wrong, please 😅

This means that there is no right or wrong on what to use. Right?

#SEHR2023

For my science, HITEMP provides empirical line lists which can be used to detect molecules in the atmospheres of exoplanets. They are not the only “providers” though and the way I understood it, there is no right or wrong on which one to use… 🤔 #SEHR2023

There are plenty of more updates that I won’t mention here. Go check out www.hitran.org if you’re interested. ✨

We move on to HITEMP (basically a part of HITRAN, but with many more lines because this is needed for hot planets). There are 8 molecules in HITEMP.

#SEHR2023

Line lists seem to be linked to food… what is the line shape “diet”? 😂

The latest addition is the molecule CH3CN. So you see, the molecules get more and more complex.

For Ozone, the latest update resulted in improved consistency between different wavelength regions.

HITRAN offers broadening parameters for key planetary molecules in HITRAN2020. #SEHR2023

Next up we have Robert Hargreaves about “HITRAN and HITEMP data for high resolution exoplanet spectroscopy”

Both HITRAN and HITEMP are databases for molecular spectroscopic parameters. The latest release is called HITRAN2020 and contains a lot of useful info, and also increased accuracy, new additions and expanded spectral coverage.

#SEHR2023