相关论文: New constraints on the HR 8799 planetary system fr…

Mid-infrared imaging traces the sub-micron and micron sized dust grains in protoplanetary disks and it offers constraints on the geometrical properties of the disks and potential companions, particularly if those companions have…

Radial velocity and transit methods are effective for the study of short orbital period exoplanets but they hardly probe objects at large separations for which direct imaging can be used. We carried out the international deep planet survey…

The multi planet system HR8799 is the first target observed with MIRI's coronagraphs as part of the MIRI-EC Guaranteed Time Observations exoplanets programme in Nov. 2022. We obtained deep observations in three coronagraphic filters from 10…

Direct imaging of exoplanetary systems is a powerful technique that can reveal Jupiter-like planets in wide orbits, can enable detailed characterization of planetary atmospheres, and is a key step towards imaging Earth-like planets. Imaging…

We place the first constraints on binary planets and exomoons from Doppler monitoring of directly imaged exoplanets. We model radial velocity observations of HR 8799 b, c, and d from Ruffio et al. (2021) and determine upper limits on the…

We analyzed the combined near-infrared spectrum of a star-planet system with thermal emission atmospheric models, based on the composition and physical parameters of the system. The main objective of this work is to obtain the inclination…

To date, infrared interferometry at best achieved contrast ratios of a few times $10^{-4}$ on bright targets. GRAVITY, with its dual-field mode, is now capable of high contrast observations, enabling the direct observation of exoplanets. We…

We obtained spectra, in the wavelength range \lambda = 995 - 1769 nm, of all four known planets orbiting the star HR 8799. Using the suite of instrumentation known as Project 1640 on the Palomar 5-m Hale Telescope, we acquired data at two…

HR\,8799 is a young planetary system composed of 4 planets and a double debris belt. Being the first multi-planetary system discovered with the direct imaging technique, it has been observed extensively since 1998. This wide baseline of…

Time-resolved photometry is an important new probe of the physics of condensate clouds in extrasolar planets and brown dwarfs. Extreme adaptive optics systems can directly image planets, but precise brightness measurements are challenging.…

We present direct imaging observations at wavelengths of 3.3, 3.8 (L',band), and 4.8 (M band) microns, for the planetary system surrounding HR 8799. All three planets are detected at L'. The c and d component are detected at 3.3 microns,…

The direct imaging of rocky exoplanets is one of the major science goals for upcoming large telescopes. The contrast requirement for imaging such planets is challenging. However, the mid-IR (InfraRed) regime provides the optimum contrast to…

The planetary system discovered around the young A-type HR8799 provides a unique laboratory to: a) test planet formation theories, b) probe the diversity of system architectures at these separations, and c) perform comparative…

The extrasolar planetary system around HR 8799 is the first multiplanet system ever imaged. It is also, by a wide margin, the highest mass system with >27 Jupiters of planetary mass past 25 AU. This is a remarkable system with no analogue…

Gas-giant planets emit a large fraction of their light in the mid-infrared ($\gtrsim$3$\mu$m), where photometry and spectroscopy are critical to our understanding of the bulk properties of extrasolar planets. Of particular importance are…

Using the Keck Planet Imager and Characterizer (KPIC), we obtained high-resolution (R$\sim$35,000) $K$-band spectra of the four planets orbiting HR 8799. We clearly detected \water{} and CO in the atmospheres of HR 8799 c, d, and e, and…

The discovery of three planetary companions around HR 8799 (Marois et al. 2008) marked a significant epoch in direct imaging of extrasolar planets. Given the importance of this system, we re-analyzed H band images of HR 8799 obtained with…

HR 8799 harbors arguably the first and best-studied directly-imaged planets. In this brief article, I describe how the HR 8799 planetary system is a benchmark system for studying the atmospheres, orbital properties, dynamical stability, and…

With about 700 confirmed extrasolar planets, it is time to move beyond discovery and towards characterization. Perhaps the most basic parameter of an extrasolar planet is its mass; however, this is very difficult to determine if the planet…

We present a pre-discovery H-band image of the HR 8799 planetary system that reveals all three planets in August 2007. The data were obtained with the Keck adaptive optics system, using angular differential imaging and a coronagraph. We…