A search for photometric variability in the young T3.5 planetary-mass companion GU Psc b

Abstract

We present a photometric $J$-band variability study of GU Psc b, a T3.5 co-moving planetary-mass companion (9-13$M_{\mathrm{Jup}}$) to a young ($\sim$150 Myr) M3 member of the AB Doradus Moving Group. The large separation between GU Psc b and its host star (42") provides a rare opportunity to study the photometric variability of a planetary-mass companion. The study presented here is based on observations obtained from 2013 to 2014 over three nights with durations of 5-6 hr each with the WIRCam imager at Canada-France-Hawaii Telescope. Photometric variability with a peak-to-peak amplitude of $4\pm 1$% at a timescale of $\sim$6 hr was marginally detected on 2014 October 11. No high-significance variability was detected on 2013 December 22 and 2014 October 10. The amplitude and timescale of the variability seen here, as well as its evolving nature, is comparable to what was observed for a variety of field T dwarfs and suggests that mechanisms invoked to explain brown dwarf variability may be applicable to low-gravity objects such as GU Psc b. Rotation-induced photometric variability due to the formation and dissipation of atmospheric features such as clouds is a plausible hypothesis for the tentative variation detected here. Additional photometric measurements, particularly on longer timescales, will be required to confirm and characterize the variability of GU Psc b, determine its periodicity and to potentially measure its rotation period.

arXiv comment17 pages, 12 figures

References in corpus (43)

• Precipitating Condensation Clouds in Substellar Atmospheres
• Rotation Periods of 34,030 Kepler Main-Sequence Stars: The Full Autocorrelation Sample
• A Giant Planet Candidate near a Young Brown Dwarf
• Validation of Kepler's Multiple Planet Candidates. III: Light Curve Analysis & Announcement of Hundreds of New Multi-planet Systems
• A self-consistent, absolute isochronal age scale for young moving groups in the solar neighbourhood
• The fast spin-rotation of a young extrasolar planet
• Clouds and Chemistry: Ultracool Dwarf Atmospheric Properties from Optical and Infrared Colors
• Weather on Other Worlds. II. Survey Results: Spots Are Ubiquitous on L and T Dwarfs
• Photometric Variability of the T2.5 Brown Dwarf SIMP J013656.5+093347; Evidence for Evolving Weather Patterns
• Brown Dwarfs and the TW Hya Association
• Discovery of Two T Dwarf Companions with the Spitzer Space Telescope
• A lithium depletion boundary age of 21 Myr for the Beta Pictoris moving group
• HST Spectral Mapping of L/T Transition Brown Dwarfs Reveals Cloud Thickness Variations
• Large Amplitude Variations of an L/T Transition Brown Dwarf: Multi-Wavelength Observations of Patchy, High-Contrast Cloud Features
• A global cloud map of the nearest known brown dwarf
• Strong Brightness Variations Signal Cloudy-to-Clear Transition of Brown Dwarfs
• Atmospheric dynamics of brown dwarfs and directly imaged giant planets
• Vertical Atmospheric Structure in a Variable Brown Dwarf: Pressure-dependent Phase Shifts in Simultaneous Hubble Space Telescope-Spitzer Light Curves
• BANYAN. IV. Fundamental parameters of low-mass star candidates in nearby young stellar kinematic groups - Isochronal Age determination using Magnetic evolutionary models
• Brown Dwarf Photospheres are Patchy: A Hubble Space Telescope Near-infrared Spectroscopic Survey Finds Frequent Low-level Variability
• Discovery of a wide planetary-mass companion to the young M3 star GU Psc
• Clouds in the Coldest Brown Dwarfs: FIRE Spectroscopy of Ross 458C
• A Combined VLT and Gemini Study of the Atmosphere of the Directly-Imaged Planet, beta Pictoris b
• The near-infrared spectral energy distribution of β Pictoris b
• Fast-evolving weather for the coolest of our two new substellar neighbours
• $ExtrasolarStorms$: Pressure-dependent Changes In Light Curve Phase In Brown Dwarfs From Simultaneous $Hubble$ and $Spitzer$ Observations
• Weather on the Nearest Brown Dwarfs: Resolved Simultaneous Multi-Wavelength Variability Monitoring of WISE J104915.57-531906.1AB
• Discovery of Rotational Modulations in the Planetary-Mass Companion 2M1207b: Intermediate Rotation Period and Heterogeneous Clouds in a Low Gravity Atmosphere
• The Brown dwarf Atmosphere Monitoring (BAM) Project I: The largest near-IR monitoring survey of L- & T-dwarfs
• An independent analysis of the brown dwarf atmosphere monitoring (BAM) data: large-amplitude variability is rare outside the L/T transition
• High-Cadence, High-Contrast Imaging for Exoplanet Mapping: Observations of the HR 8799 Planets with VLT/SPHERE Satellite Spot-Corrected Relative Photometry
• Spectral Variability from the Patchy Atmospheres of T and Y Dwarfs
• Temperature Fluctuations as a Source of Brown Dwarf Variability
• Variability in a Young, L/T Transition Planetary-Mass Object
• SIMP J013656.5+093347 is Likely a Planetary-Mass Object in the Carina-Near Moving Group
• Cloud structure of the nearest brown dwarfs: Spectroscopic variability of Luhman 16AB from the Hubble Space Telescope
• Cloud Atlas: Discovery of Patchy Clouds and High-amplitude Rotational Modulations In a Young, Extremely Red L-type Brown Dwarf
• The First Detection of Photometric Variability in a Y Dwarf: WISE J140518.39+553421.3
• A Monitoring Campaign for Luhman 16AB. I. Detection of Resolved Near-Infrared Spectroscopic Variability
• HN Peg B: A Test of Models of the L to T Dwarf Transition
• Neptune's Dynamic Atmosphere from Kepler K2 Observations: Implications for Brown Dwarf Light Curve Analyses
• Mapping Directly Imaged Giant Exoplanets
• PSYM-WIDE: a survey for large-separation planetary-mass companions to late spectral type members of young moving groups

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• Cloud Atlas: Hubble Space Telescope Near-Infrared Spectral Library of Brown Dwarfs, Planetary-mass companions, and hot Jupiters
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