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Multi-planet systems exhibit a diversity of architectures that diverge from the solar system and contribute to the topic of exoplanet demographics. Radial velocity (RV) surveys form a crucial component of exoplanet surveys, as their long observational baselines allow searches for more distant planetary orbits. This work provides a significantly revised architecture for the multi-planet system HD 134606 using both HARPS and UCLES RVs. We confirm the presence of previously reported planets b, c, and d with periods $12.0897^{+0.0019}_{-0.0018}$, $58.947^{+0.056}_{-0.054}$, and $958.7^{+6.3}_{-5.9}$ days, and masses $9.14^{+0.65}_{-0.63}$, $11.0\pm1$, and $44.5\pm2.9$ Earth masses respectively, with the planet d orbit significantly revised to over double that originally reported. We report two newly detected super-Earths, e and f, with periods $4.31943^{+0.00075}_{-0.00068}$ and $26.9^{+0.019}_{-0.017}$ days, and masses $2.31^{+0.36}_{-0.35}$ and $5.52^{+0.74}_{-0.73}$ Earth masses, respectively. In addition, we identify a linear trend in the RV time series, and the cause of this acceleration is deemed to be a newly detected sub-stellar companion at large separation. HD 134606 now displays four low mass planets in a compact region near the star, one gas giant further out in the Habitable Zone, an additional massive companion in the outer regime, and a low mass M dwarf stellar companion at large separation, making it an intriguing target for system formation/evolution studies. The location of planet d in the Habitable Zone proves to be an exciting candidate for future space-based direct imaging missions, whereas continued RV observations of this system are recommended for understanding the nature of the massive, long period companion., Comment: 23 pages, 10 figures, 4 tables, accepted for publication in the Astronomical Journal

The Transiting Exoplanet Survey Satellite (TESS) provides a continuous suite of new planet candidates that need confirmation and precise mass determination from ground-based observatories. This is the case for the G-type star TOI-1710, which is known to host a transiting sub-Saturn planet ($\mathrm{M_p}=$28.3$\pm$4.7$\mathrm{M}_\oplus$) in a long-period orbit (P=24.28\,d). Here we combine archival SOPHIE and new and archival HARPS-N radial velocity data with newly available TESS data to refine the planetary parameters of the system and derive a new mass measurement for the transiting planet, taking into account the impact of the stellar activity on the mass measurement. We report for TOI-1710b a radius of $\mathrm{R_p}$$=$5.15$\pm$0.12$\mathrm{R}_\oplus$, a mass of $\mathrm{M_p}$$=$18.4$\pm$4.5$\mathrm{M}_\oplus$, and a mean bulk density of $\rho_{\rm p}$$=$0.73$\pm$0.18$\mathrm{g \, cm^{-3}}$, which are consistent at 1.2$\sigma$, 1.5$\sigma$, and 0.7$\sigma$, respectively, with previous measurements. Although there is not a significant difference in the final mass measurement, we needed to add a Gaussian process component to successfully fit the radial velocity dataset. This work illustrates that adding more measurements does not necessarily imply a better mass determination in terms of precision, even though they contribute to increasing our full understanding of the system. Furthermore, TOI-1710b joins an intriguing class of planets with radii in the range 4-8 $\mathrm{R}_\oplus$ that have no counterparts in the Solar System. A large gaseous envelope and a bright host star make TOI-1710b a very suitable candidate for follow-up atmospheric characterization., Comment: Accepted for publication in A&A. 21 pages, 14 figures

Recent advances in multi-agent reinforcement learning (MARL) are enabling impressive coordination in heterogeneous multi-robot teams. However, existing approaches often overlook the challenge of generalizing learned policies to teams of new compositions, sizes, and robots. While such generalization might not be important in teams of virtual agents that can retrain policies on-demand, it is pivotal in multi-robot systems that are deployed in the real-world and must readily adapt to inevitable changes. As such, multi-robot policies must remain robust to team changes -- an ability we call adaptive teaming. In this work, we investigate if awareness and communication of robot capabilities can provide such generalization by conducting detailed experiments involving an established multi-robot test bed. We demonstrate that shared decentralized policies, that enable robots to be both aware of and communicate their capabilities, can achieve adaptive teaming by implicitly capturing the fundamental relationship between collective capabilities and effective coordination. Videos of trained policies can be viewed at: https://sites.google.com/view/cap-comm, Comment: Presented at the 7th Conference on Robot Learning (CoRL 2023), Atlanta, USA

Many complex robotic manipulation tasks can be decomposed as a sequence of pick and place actions. Training a robotic agent to learn this sequence over many different starting conditions typically requires many iterations or demonstrations, especially in 3D environments. In this work, we propose Fourier Transporter (FourTran) which leverages the two-fold SE(d)xSE(d) symmetry in the pick-place problem to achieve much higher sample efficiency. FourTran is an open-loop behavior cloning method trained using expert demonstrations to predict pick-place actions on new environments. FourTran is constrained to incorporate symmetries of the pick and place actions independently. Our method utilizes a fiber space Fourier transformation that allows for memory-efficient construction. We test our proposed network on the RLbench benchmark and achieve state-of-the-art results across various tasks., Comment: ICLR 2024

Pre-main sequence disk accretion is pivotal in determining the final stellar properties and the early conditions for close-in planets. We aim to establish the impact of internal (stellar mass) and external (radiation field) parameters on disk evolution in the Lagoon Nebula massive star-forming region. We employ simultaneous $u,g,r,i,H\alpha$ time series photometry, archival infrared data, and high-precision $K2$ light curves, to derive stellar, disk, and accretion properties for 1012 Lagoon Nebula members. Of all young stars in the Lagoon Nebula, we estimate $34\%-37\%$ have inner disks traceable down to $\sim 12$ $\mu$m, while $38\%-41\%$ are actively accreting. We detect disks $\sim$1.5 times more frequently around G/K/M stars than higher-mass stars, which appear to deplete their inner disks on shorter timescales. We find tentative evidence for faster disk evolution in the central regions of the Lagoon Nebula, where the bulk of the O/B population is located. Conversely, disks appear to last longer at its outskirts, where the measured fraction of disk-bearing stars tends to exceed those of accreting and disk-free stars. The derived mass accretion rates show a non-uniform dependence on stellar mass between $\sim 0.2-5$ $M_\odot$. In addition, the typical accretion rates appear to differ across the Lagoon Nebula extension, with values two times lower in the core region than at its periphery. Finally, we detect tentative density gradients in the accretion shocks, with lags in the appearance of brightness features as a function of wavelength that can amount to $\sim7\%-30\%$ of the rotation period., Comment: 30 pages, 11 figures, two tables; accepted for publication in The Astronomical Journal

Hot Jupiters were many of the first exoplanets discovered in the 1990s, but in the decades since their discovery, the mysteries surrounding their origins remain. Here, we present nine new hot Jupiters (TOI-1855 b, TOI-2107 b, TOI-2368 b, TOI-3321 b, TOI-3894 b, TOI-3919 b, TOI-4153 b, TOI-5232 b, and TOI-5301 b) discovered by NASA's TESS mission and confirmed using ground-based imaging and spectroscopy. These discoveries are the first in a series of papers named the Migration and Evolution of giant ExoPlanets (MEEP) survey and are part of an ongoing effort to build a complete sample of hot Jupiters orbiting FGK stars, with a limiting Gaia $G$-band magnitude of 12.5. This effort aims to use homogeneous detection and analysis techniques to generate a set of precisely measured stellar and planetary properties that is ripe for statistical analysis. The nine planets presented in this work occupy a range of masses (0.55 Jupiter masses (M$_{\rm{J}}$) $<$ M$_{\rm{P}}$ $<$ 3.88 M$_{\rm{J}}$) and sizes (0.967 Jupiter radii (R$_{\rm{J}}$) $<$ R$_{\rm{P}}$ $<$ 1.438 R$_{\rm{J}}$) and orbit stars that range in temperature from 5360 K $<$ Teff $<$ 6860 K with Gaia $G$-band magnitudes ranging from 11.1 to 12.7. Two of the planets in our sample have detectable orbital eccentricity: TOI-3919 b ($e = 0.259^{+0.033}_{-0.036}$) and TOI-5301 b ($e = 0.33^{+0.11}_{-0.10}$). These eccentric planets join a growing sample of eccentric hot Jupiters that are consistent with high-eccentricity tidal migration, one of the three most prominent theories explaining hot Jupiter formation and evolution., Comment: 35 pages, 7 tables, and 14 figures. Submitted to AAS Journals on 2023 Dec 28