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تسجيل مستخدم جديدA 5 Micron Image of beta Pictoris b at a Sub-Jupiter Projected Separation: Evidence for a Misalignment Between the Planet and the Inner, Warped Disk
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We present and analyze a new M detection of the young exoplanet beta Pictoris b from 2008 VLT/NaCo data at a separation of ~ 4 AU and a high signal-to-noise rereduction of L data taken in December 2009. Based on our orbital analysis, the planets orbit is viewed almost perfectly edge-on (i ~ 89 degrees) and has a Saturn-like semimajor axis of 9.50 (+3.93, -1.7) AU. Intriguingly, the planets orbit is aligned with the major axis of the outer disk (Omega ~ 31 degrees) but probably misaligned with the warp/inclined disk at 80 AU often cited as a signpost for the planets existence. Our results motivate new studies to clarify how $beta$ Pic b sculpts debris disk structures and whether a second planet is required to explain the warp/inclined disk.
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We present $H$-band observations of $beta$ Pic with the Gemini Planet Imagers (GPIs) polarimetry mode that reveal the debris disk between ~0.3 (~6 AU) and ~1.7 (~33 AU), while simultaneously detecting $beta$ Pic $b$. The polarized disk image was fit
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Our objective is to estimate the C/O ratio in the atmosphere of beta Pictoris b and obtain an estimate of the dynamical mass of the planet, as well as to refine its orbital parameters using high-precision astrometry. We used the GRAVITY instrument wi
th the four 8.2 m telescopes of the Very Large Telescope Interferometer to obtain K-band spectro-interferometric data on $beta$ Pic b. We extracted a medium resolution (R=500) K-band spectrum of the planet and a high-precision astrometric position. We estimated the planetary C/O ratio using two different approaches (forward modeling and free retrieval) from two different codes (ExoREM and petitRADTRANS, respectively). Finally, we used a simplified model of two formation scenarios (gravitational collapse and core-accretion) to determine which can best explain the measured C/O ratio. Our new astrometry disfavors a circular orbit for $beta$ Pic b ($e=0.15^{+0.05}_{-0.04}$). Combined with previous results and with Hipparcos/GAIA measurements, this astrometry points to a planet mass of $M = 12.7pm{}2.2,M_mathrm{Jup}$. This value is compatible with the mass derived with the free-retrieval code petitRADTRANS using spectral data only. The forward modeling and free-retrieval approches yield very similar results regarding the atmosphere of beta Pic b. In particular, the C/O ratios derived with the two codes are identical ($0.43pm{}0.05$ vs $0.43^{+0.04}_{-0.03}$). We argue that if the stellar C/O in $beta$ Pic is Solar, then this combination of a very high mass and a low C/O ratio for the planet suggests a formation through core-accretion, with strong planetesimal enrichment.
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We present deep HST/STIS coronagraphic images of the Beta Pic debris disk obtained at two epochs separated by 15 years. The new images and the re-reduction of the 1997 data provide the most sensitive and detailed views of the disk at optical waveleng
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Using the Gemini Planet Imager (GPI) located at Gemini South, we measured the near-infrared (1.0-2.4 micron) spectrum of the planetary companion to the nearby, young star $beta$ Pictoris. We compare the spectrum obtained with currently published mode
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