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25 of 25 filled cells are backed by a passage of the paper.

PaperQuestionMethodDataMain resultsLimitations
1 Combining TTVs, RVs, and astrometry to characterize distant giant companions of transiting hot Jupiters: Application to WASP-4 Characterize the distant giant companion WASP-4 c and determine whether the transit-timing behavior of WASP-4 b indicates orbital decay.
Source · Abstract, ¶1
We examine the WASP-4 system using newly obtained ESO$\,$3.6/HARPS radial velocity (RV) observations and archival transit-timing data, leveraging the LTTE.
Open in the paper
Jointly model radial velocities, transit timing through the light travel-time effect, and astrometry. Use injection–recovery simulations to assess the contribution of Gaia observations.
Source · Abstract, ¶1
We combine and fit all currently available data and simulate $\textit{Gaia}$ DR4 and DR5 astrometric measurements of WASP-4 and perform an injection and recovery procedure to estimate their impact on the recovered planetary parameters of WASP-4$\,$c. The procedure employs a combined model that describes RVs, transit timing variations (TTVs) via the LTTE, and astrometry simultaneously.
Open in the paper
Use archival transit timings and CORALIE, HIRES, and reanalyzed HARPS radial velocities, supplemented by new HARPS observations in 2024–2025. Gaia measurements are simulated rather than observed.
Source · 2 Observations, ¶2
Regarding the RV data, we took the CORALIE RVs from Turner et al. (2022) and the HIRES data from Winn and Stefánsson (2025), who added one additional RV measurement. We re-analyzed all available HARPS data ourselves.

Not in this passage: 2024

Open in the paper
WASP-4 c has a minimum mass of 9.3 ± 1.7 Jupiter masses and a period of 10,600 days (+1,100/−1,000); no significant decay of WASP-4 b is found. Simulated Gaia DR5 joint fits reduce uncertainties in period, conjunction time, and RV amplitude by about 10%, 25%, and 33%, respectively.
Source · Abstract, ¶1
Analyzing the existing data, we improve the planetary parameters of WASP-4$\,$c, finding a minimum mass of $9.3\pm1.7\,M_\mathrm{Jup}$ with an orbital period of $10\,600^{+1100}_{-1000}\,$d, or about $29\,$yr. Furthermore, we find that there is no significant orbital decay taking place for WASP-4$\,$b.

Not in this passage: 1.7, 10600, 25, 33

Open in the paper
Long orbital periods and low companion masses can make companions difficult to detect with astrometry alone.
Source · 6 Conclusions, ¶3
While some of the cold companions may be hidden to just the astrometric data due to long orbital periods or masses below the detection threshold, the combination with RVs and TTVs can help to extend the observational baseline and sensitivity, a
Open in the paper
2 The COBREX archival survey: improved constraints on the occurrence rate of wide-orbit substellar companions. I. A uniform re-analysis of 400 stars from the GPIES survey Improve direct-imaging sensitivity and constrain the occurrence of wide-orbit giant planets and brown dwarf companions through a uniform archival reanalysis.
Source · Abstract
In the context of the COBREX project, we have assembled the largest collection of archival DI observations to date in order to undertake a large and uniform re-analysis. In particular, this paper details the re-analysis of 400 stars from the GPIES survey operated at GPI@Gemini South.
 Process imaging cubes with PACO and assess candidates using multi-epoch proper motion and color–magnitude information. Convert detection limits into detectability maps to estimate occurrence rates.
Source · Abstract
Candidates were identified and vetted based on multi-epoch proper motion analysis -- whenever possible -- and by means of a suitable color-magnitude diagram. The conversion of detection limits into detectability maps allowed for an estimate of unbiased occurrence frequencies of giant planets and brown dwarfs.
 Archival GPI direct-imaging observations of 400 stars from the GPIES survey at Gemini South.
Source · Abstract
In particular, this paper details the re-analysis of 400 stars from the GPIES survey operated at GPI@Gemini South.
 Minimum detectable masses improve by up to a factor of two; two candidates remain unconfirmed. The abstract reports an occurrence of 1.7% (+0.9/−0.7) for 5–13 Jupiter-mass planets at 10–100 au, rising to 2.2% (+1.0/−0.8) when companions up to 80 Jupiter masses are included.
Source · Abstract
Deeper detection limits were derived compared to the literature, with up to a twofold gain in minimum detectable mass compared to previous GPI-based publications. Although no new substellar companion was confirmed, we identified two interesting planet candidates awaiting follow-up observations.

Not in this passage: 0.7, 0.8, 0.9, 1.0, 1.7

 The suggested excess of brown dwarf companions around FGK rather than BA stars is not statistically significant. Low occurrence rates, host-mass diversity, formation-channel overlap, and input assumptions limit more detailed population analysis.
Source · Abstract
Although the BD trend is not statistically significant, an in- teresting analogy might be drawn with the behavior of the two empirical distributions of substellar companions introduced by Vigan et al. (2021) in the context of SHINE.
3 A Model to Map Brown Dwarf Companions to White Dwarfs in Partial Secondary Eclipse Determine whether partial secondary eclipses can reveal spatial emission patterns on brown dwarf companions to white dwarfs, including latitude-dependent atmospheric circulation.
Source · Abstract, ¶1
We adapt the eigenmapping method to disentangle the signals from the ever- and never-occulted regions.
Open in the paper
Separate phase-curve and eclipse information using eigenmapping, then regularize spherical-harmonic maps with Tikhonov penalties. Test recovery with synthetic latitude structures and general circulation model emission, and compare models using BIC.
Source · Abstract, ¶1
We introduce a model that penalizes the harmonic complexity of the model map with Tikhonov regularization, whose parameters are tuned to reproduce the fit quality of the eigenmapping model.
Open in the paper
Use full-orbit JWST NIRSpec/PRISM observations of WD 1202-024 and simulated light curves based on those observations. The observation spans 90.7 minutes, with 50 original integrations subsequently divided into 600 time-resolved images.
Source · II.2 Observations and Data Reduction, ¶1
The observation covers 90.7 minutes across 50 integrations of 120 groups each.

Not in this passage: 024, 1202, 600

Open in the paper
Recovering the simulated equatorial-jet signature is statistically favored only at about three times the observed signal-to-noise ratio. The actual data favor a full-phase eigenbasis map with an approximately 15° substellar hotspot, unlike the circulation-model prediction.
Source · Abstract, ¶1
Such a model, however, is only statistically preferred at approximately $3 \times$ the signal-to-noise ratio of the JWST data.

Not in this passage: 15

Open in the paper
The inferred hotspot cannot yet be confidently interpreted because instrumental systematics and genuine emission signals remain difficult to separate.
Source · Abstract, ¶1
Interpreting this result more carefully requires follow-up work to disentangle systematics from true emission signals.
Open in the paper
4 Expanding the Volatile Abundance Inventory for High-Priority K-Dwarf JWST Exoplanet Systems Measure carbon and oxygen elemental and isotopic abundances in six K-dwarf exoplanet hosts to establish chemical reference points for planetary atmospheric studies.
Source · Abstract, ¶1
To address the need for K dwarf abundance constraints, we present an elemental ([C/H], [O/H]) and isotopic ($^{12}$C/$^{13}$C, $^{16}$O/$^{18}$O) abundance analysis for six K dwarf exoplanet host stars: K2-141, NGTS-10, WASP-43, WASP-69, WASP-80, and HATS-72.
Open in the paper
Fit near-infrared OH and CO features using MARCS atmospheres and TurboSpectrum spectral synthesis. Determine elemental abundances before fitting carbon isotope ratios, and estimate uniform gyrochronological ages.
Source · Abstract, ¶1
Using MARCS model atmospheres, the TurboSpectrum spectral synthesis code, and near-infrared IGRINS spectra, we derive novel [C/H] and [O/H] abundance ratios for these high-priority K dwarf host stars.
Open in the paper
Analyze high-resolution IGRINS H- and K-band spectra of K2-141, NGTS-10, WASP-43, WASP-69, WASP-80, and HATS-72. Spectra come from archival observations and the authors’ observing programs.
Source · III The K Dwarf Sample, ¶2
The sample consists of six exoplanet host stars: K2-141, NGTS-10, WASP-43, WASP-69, WASP-80, and HATS-72.
Open in the paper
Derive new carbon and oxygen elemental abundances and find subsolar carbon-12/carbon-13 ratios in five of six stars. Oxygen-16/oxygen-18 ratios cannot be measured from these spectra.
Source · Abstract, ¶1
The observed spectra are too noisy to measure $^{16}$O/$^{18}$O ratios for the sample, but we do find sub-solar $^{12}$C/$^{13}$C ratios for five out of six targets.
Open in the paper
Spectral noise prevents oxygen isotope-ratio measurements for every star in the sample.
Source · Abstract, ¶1
The observed spectra are too noisy to measure $^{16}$O/$^{18}$O ratios for the sample, but we do find sub-solar $^{12}$C/$^{13}$C ratios for five out of six targets.
Open in the paper
5 The anomalously large transiting planet around Boyajian's star: evidence for a circumplanetary ring Test whether a circumplanetary ring can explain the apparently oversized giant-planet candidate around Boyajian’s star without requiring an anomalously large planetary radius.
Source · Abstract, ¶1
Here we explore the solution that the planet is actually ringed. We develop a fast and accurate code to compute the transit light curve due to a ringed planet, and apply it to the TESS light curve.
Open in the paper
Compare spherical-planet and ringed-planet transit fits using the JoJo boundary-integration algorithm. Adopt a physically motivated planet radius of 1.1 Jupiter radii and constrain ring configurations using the Roche limit.
Source · III Implementation of the ring model in…
Here we adopt the key algorithm of JoJo, first proposed in Liu et al. [18] and used to model the transit light curve due to an oblate planet [17], and apply it to the ring situation.

Not in this passage: 1.1

Open in the paper
Use the single transit observed in the TESS Sector 15 light curve, sampled at two-minute cadence. Detrend a three-day segment around the event using an out-of-transit quadratic baseline.
Source · II.1 TESS light curve, ¶1
We analyzed the TESS light curve of KIC 8462852 (Boyajian’s star) obtained during Sector 15 (2019 August 15 – September 10), which covers the single-transit event reported by Madurga-Favieres et al. [19]. We used the pre-search data conditioned (PDC) light curve at the short-cadence (2-min) sampling produced by the Science Processing Operations Center (SPOC) pipeline [13], retrieved from the Mikulski Archive for Space Telescopes (MAST).
Open in the paper
A 1.1-Jupiter-radius planet with an opaque, nearly polar ring extending to 3.1–4.4 planetary radii can explain the transit. The ring improves chi-squared by about 14 with two extra parameters, but the BIC advantage is only 0.4–1.3.
Source · Abstract, ¶1
The preferred configuration is a Jupiter-sized ($1.1\,R_{\rm J}$) planet surrounded by an opaque, highly flattened ring extending to $3.1$--$4.4$ planetary radii with a nearly polar obliquity.

Not in this passage: 0.4, 1.3, 14

Open in the paper
The ring interpretation has only marginal statistical support, and its geometry is uncertain. TESS noise and the model’s flexibility require physically motivated assumptions.
Source · IV Ring model fit to the TESS light cur…
Given the relatively high noise level of TESS data and the flexibility of the ring model, it is necessary to make a few reasonable assumptions about the ring model in order to make it physically plausible.
Open in the paper

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