Merge pull request #9 from FormingWorlds/tl/l14-figure-swaps-2026-04-24

L14: Mulders 2024 true source identified + Lichtenberg 2025 mass-radius

Author: timlichtenberg

book/14_synthesis/figures/lichtenberg2025_mass_radius.avif

@@ -109,11 +109,11 @@ Compact multi-planet systems with four or more transiting planets interior to 1.
 
 The mass-radius diagram offers a complementary view ({numref}`fig:l14:massrad`). Plotting bulk density implied by mass and radius for the planets in the solar system and for the exoplanets where both quantities are known, one sees that the rocky planets cluster along a narrow track set by the equation of state of silicate mantles and iron cores, while the larger planets spread out into the volatile-rich and the gas-dominated regimes. The solar system terrestrials sit firmly on the "Earth-like" composition curve. Many close-in exoplanet super-Earths sit on the same curve too, indicating that the population of bare rocky cores is real, but a substantial subset of slightly larger planets sits *above* the rocky line, indicating that they retain significant volatile envelopes that swell their radii relative to a pure-rock composition.
 
-```{figure} figures/wordsworth2022_mass_radius.avif
+```{figure} figures/lichtenberg2025_mass_radius.avif
 :name: fig:l14:massrad
-:width: 80%
+:width: 95%
 
-Mass-radius diagram for solar system rocky planets and small exoplanets, with theoretical equation-of-state tracks for compositions ranging from pure iron through Earth-like rocky to pure water. The solar system terrestrials sit on the Earth-like curve. The exoplanets above that curve are inferred to retain volatile envelopes, the most common interpretation being H/He on top of a rocky core (the "sub-Neptune" population). Reproduced from {cite:t}`Wordsworth2022`.
+Mass-radius diagram for rocky and small exoplanets from {cite:t}`Lichtenberg2025` Fig. 2. Data points are observed exoplanets with measured masses and radii, colour-coded by equilibrium temperature into **temperate** (blue), **bistable** (light blue), **lava** (red), and **rock-vapour** (orange) regimes; symbol shape marks **high-priority** atmospheric-characterisation targets (diamonds) and lower-priority targets (circles). Labelled planets include TRAPPIST-1 b through h, GJ 367 b, GJ 1132 b, GJ 486 b, K2-18 b, K2-141 b, LHS 1140 b, L 98-59 b/c/d, GJ 1252 b, LTT 1445 A b, and several TOI targets. Theoretical equation-of-state tracks range from **100% Fe** (bottom) through **Earth-like** rocky and **100% MgSiO$_3$**, with volatile-rich tracks for **Earth-like + 50 wt% H$_2$O**, **magma ocean + 0.1 wt%** or **5.4 wt% H$_2$O**, and a **gas-dwarf birth + H/He boil-off** curve that bounds the potential sub-Neptune population (shaded at upper left). Solar-system terrestrials sit on the Earth-like curve; exoplanets above it either retain volatile envelopes (H/He, water, or melt-water mixtures) or are otherwise reshaped by magma-ocean outgassing and photoevaporation. Reproduced from {cite:t}`Lichtenberg2025`.
 ```
 
 ### "Is the solar system rare?"
@@ -130,11 +130,11 @@ What we can say with confidence is that the inner solar system is *atypical* rel
 
 The reverse statement, that planet *occurrence rates depend strongly on stellar type*, is by now well established. {numref}`fig:l14:mulders-occurrence` shows the close-in (period $< 50$ days) small-planet occurrence rate as a function of stellar effective temperature, compiled from a decade of Kepler, K2, and ground-based surveys: rocky and sub-Neptune-sized planets are roughly twice as common around early M dwarfs as around F and G dwarfs, and the trend continues into the late M regime. Whether this trend reflects formation efficiency in lower-mass disks or detection bias in different survey samples is still being debated, but the headline conclusion, that "Earth-sized planets are not rare around low-mass stars", is robust.
 
-```{figure} figures/mulders2018_occurrence_vs_teff.avif
+```{figure} figures/mulders2024_occurrence_vs_teff.avif
 :name: fig:l14:mulders-occurrence
 :width: 80%
 
-Average number of close-in planets per star (orbital period less than 50 days) as a function of host-star effective temperature, compiled from a representative subset of Kepler, K2, and M-dwarf transit and radial-velocity surveys (Howard+12, Mulders+15, Hardegree-Ullman+19, Yang+20, He+21, Sabotta+21, Bergsten+22, Ment & Charbonneau23). The occurrence rate rises by about a factor of 2 from F dwarfs ($\sim 6500$ K) to early M dwarfs ($\sim 3500$ K), then drops slightly toward the latest M types where the surveys are smallest and the most uncertain. The takeaway is that small close-in planets are most common around the most numerous class of stars in the galaxy. Composite figure compiled for this course from the cited literature; the headline demographic trend is reviewed in {cite:t}`Bergsten2022`.
+Overview of planet occurrence rates as a function of host-star effective temperature, for planets between $1$–$4\,\Rearth$ on orbital periods $P < 50$ days, from {cite:t}`Mulders2024` Fig. 5. Rates were re-scaled assuming uniform occurrence in $\log P$ and $\log R$ for cross-study comparison. Plotted data are compiled from Howard+12, Mulders+15, Hardegree-Ullman+19, Yang+20, He+21, Sabotta+21, {cite:t}`Bergsten2022`, and Ment & Charbonneau 23 (see {cite:t}`Mulders2024` for full references). Across all studies, planet occurrence increases by roughly a factor of 2 from F dwarfs ($\sim 6500$ K) to early M dwarfs ($\sim 3500$ K); a break appears toward late M dwarfs, but those surveys sample only very short periods ($< 10$ d) so the late-M values are lower limits. The headline message is that small, close-in planets are most common around the most numerous class of stars in the galaxy. Reproduced from {cite:t}`Mulders2024`.
 ```
 
 

…ures/mulders2018_occurrence_vs_teff.avif …ures/mulders2024_occurrence_vs_teff.avifbook/14_synthesis/figures/mulders2018_occurrence_vs_teff.avif renamed to book/14_synthesis/figures/mulders2024_occurrence_vs_teff.avif book/14_synthesis/figures/mulders2018_occurrence_vs_teff.avif renamed to book/14_synthesis/figures/mulders2024_occurrence_vs_teff.avif

@@ -527,6 +527,17 @@ @article{Lichtenberg2021
     url     = {https://ui.adsabs.harvard.edu/abs/2021Sci...371..365L/abstract}
 }
 
+@article{Lichtenberg2025,
+    author  = {Lichtenberg, Tim and Shorttle, Oliver and Teske, Johanna and Kempton, Eliza M.-R.},
+    title   = {Constraining exoplanet interiors using observations of their atmospheres},
+    journal = {Science},
+    volume  = {390},
+    pages   = {eads3360},
+    year    = {2025},
+    doi     = {10.1126/science.ads3360},
+    url     = {https://ui.adsabs.harvard.edu/abs/2025Sci...390S3660L/abstract}
+}
+
 @article{Grewal2019,
     author  = {Grewal, Damanveer S. and Dasgupta, Rajdeep and Sun, Chenguang and Tsuno, Kyusei and Costin, Gelu},
     title   = {Delivery of carbon, nitrogen, and sulfur to the silicate {Earth} by a giant impact},
@@ -4869,19 +4880,21 @@ @article{Bergsten2022
     url           = {https://ui.adsabs.harvard.edu/abs/2022AJ....164..190B/abstract}
 }
 
-@incollection{Mulders2018,
+@incollection{Mulders2024,
     author        = {Mulders, Gijs D.},
     title         = {Exoplanet Populations and their Dependence on Host Star Properties},
     booktitle     = {Handbook of Exoplanets},
+    edition       = {2nd},
     editor        = {Deeg, Hans J. and Belmonte, Juan Antonio},
-    publisher     = {Springer International Publishing},
-    year          = {2018},
-    pages         = {153},
-    doi           = {10.1007/978-3-319-55333-7_153},
+    publisher     = {Springer},
+    address       = {Cham},
+    year          = {2024},
+    doi           = {10.1007/978-3-319-30648-3_153-2},
     eprint        = {1805.00023},
     archivePrefix = {arXiv},
     primaryClass  = {astro-ph.EP},
-    url           = {https://ui.adsabs.harvard.edu/abs/2018haex.bookE.153M/abstract},
+    note          = {Updated chapter with arXiv v2 revisions as of 4 March 2024},
+    url           = {https://link.springer.com/rwe/10.1007/978-3-319-30648-3_153-2}
 }
 
 @article{Niemann1998,

book/14_synthesis/figures/wordsworth2022_mass_radius.avif

@@ -1044,3 +1044,13 @@ Final two active §M6 items closed via a continuation of the Tim-in-the-loop scr
 **Tooling**: added `tmp_images/` to `.gitignore` so that transient screenshot uploads during paywalled-figure sessions can never be accidentally committed.
 
 All §M6 items that require action are now closed on main. Remaining full-course-review residue: **L14 Mulders true source** (interim Bergsten2022 caption applied in PR #4; the actual composite source is still unknown and likely blocked on Tim's archive) and **L4 content expansion** (meta-review recommendation #5, discretionary).
+
+### 7.9 L14 figure swaps 2026-04-24: Mulders 2024 true source identified + Lichtenberg 2025 Science mass-radius
+
+Final clean-up round on two L14 figures.
+
+**L14 mulders-occurrence figure — TRUE SOURCE IDENTIFIED**: after a systematic search through candidate papers (Mulders 2018 Handbook v1, Bergsten+Pascucci+Mulders 2022, Bergsten+Pascucci+Hardegree-Ullman+Fernandes+Christiansen+Mulders 2023, Hardegree-Ullman et al. Scaling K2 VIII 2025, Pascucci APAC 2024 presentation), the actual source turned out to be **Mulders 2024 Fig. 5** — the *updated v2* of the Handbook of Exoplanets chapter (arXiv:1805.00023v2, submitted 4 March 2024; Springer 2nd edition DOI 10.1007/978-3-319-30648-3_153-2). Mulders himself compiled the literature compilation for the 2024 revision, listing all 8 studies in his Fig. 5 caption that match our figure's legend exactly (Howard+12, Mulders+15, Hardegree-Ullman+19, Yang+20, He+21, Sabotta+21, Bergsten+22, Ment & Charbonneau 23). Action: renamed bib key `Mulders2018` -> `Mulders2024` with the updated DOI and edition metadata; renamed figure file `mulders2018_occurrence_vs_teff.avif` -> `mulders2024_occurrence_vs_teff.avif`; updated the L14 `{figure}` directive and the caption to cite `Mulders2024` as the direct source (no longer an anonymous "compiled for this course" composite). The PR #4 interim `Bergsten2022` anchor citation is kept as a secondary in-caption cite because that paper is one of the data sources.
+
+**L14 fig:l14:massrad — swapped Wordsworth 2022 -> Lichtenberg 2025 Science (Fig. 2)**: the old `wordsworth2022_mass_radius.avif` was replaced with Fig. 2 from `Lichtenberg, Shorttle, Teske, Kempton 2025 Science 390, eads3360` ("Constraining exoplanet interiors using observations of their atmospheres", DOI 10.1126/science.ads3360). The new figure shows mass-radius with planets colour-coded by equilibrium temperature (temperate/bistable/lava/rock-vapour), symbol-shape-coded by atmospheric-characterisation priority (high/low), and seven EOS compositional tracks (100% Fe, Earth-like, Earth-like + 50 wt% H2O, magma ocean + 0.1 or 5.4 wt% H2O, 100% MgSiO3, and gas-dwarf birth + H/He boil-off). Much richer pedagogical content than the old Wordsworth 2022 figure. New bib entry `Lichtenberg2025` added (ADS-verified bibcode 2025Sci...390S3660L). Old `wordsworth2022_mass_radius.avif` deleted from disk; `Wordsworth2022` bib entry retained because it is still cited for the L14 tidal-couplings figure and in L5.
+
+L14 figure count unchanged (30 figures); no drift in course-wide figure numbering.