Diffuser-assisted Photometric Follow-up Observations of the Neptune-sized Planets K2-28b and K2-100b

Abstract

We present precision transit observations of the Neptune-sized planets K2-28b and K2-100b, using the Engineered Diffuser on the ARCTIC imager on the ARC 3.5m Telescope at Apache Point Observatory. K2-28b is a $R_p=2.56R_{\oplus }$ mini-Neptune transiting a bright (J=11.7) metal-rich M4 dwarf, offering compelling prospects for future atmospheric characterization. K2-100b is a $R_p=3.45R_{\oplus }$ Neptune in the Praesepe Cluster and is one of few planets known in a cluster transiting a host star bright enough ($V=10.5$) for precision radial velocity observations. Using the precision photometric capabilities of the diffuser/ARCTIC system, allows us to achieve a precision of $105_{-37}^{+87}$ppm, and $38_{-11}^{+21}$ppm in 30 minute bins for K2-28b, and K2-100b, respectively. Our joint-fits to the K2 and ground-based light-curves give an order of magnitude improvement in the orbital ephemeris for both planets, yielding a timing precision of 2min in the JWST era. Although we show that the currently available broad-band measurements of K2-28b's radius are currently too imprecise to place useful constraints on K2-28b's atmosphere, we demonstrate that JWST/NIRISS will be able to discern between a cloudy/clear atmosphere in a modest number of transit observations. Our light-curve of K2-100b marks the first transit follow-up observation of this challenging-to-observe transit, where we obtain a transit depth of $819\pm 50\mathrm{ppm}$ in the SDSS $i^{\prime }$ band. We conclude that diffuser-assisted photometry can play an important role in the TESS era to perform timely and precise follow-up of the expected bounty of TESS planet candidates.

arXiv comment14 pages, 4 figures, submitted to AAS journals

References in corpus (70)

• Astropy: A Community Python Package for Astronomy
• emcee: The MCMC Hammer
• The NumPy array: a structure for efficient numerical computation
• Analytic Lightcurves for Planetary Transit Searches
• The K2 Mission: Characterization and Early results
• Cosmic-Ray Rejection by Laplacian Edge Detection
• The California-Kepler Survey. III. A Gap in the Radius Distribution of Small Planets
• batman: BAsic Transit Model cAlculatioN in Python
• A box-fitting algorithm in the search for periodic transits
• Prevalence of Earth-size planets orbiting Sun-like stars
• On detecting terrestrial planets with timing of giant planet transits
• DHP Framework: Digital Health Passports Using Blockchain -- Use case on international tourism during the COVID-19 pandemic
• EXOFAST: A fast exoplanetary fitting suite in IDL
• Architecture of Kepler's Multi-transiting Systems: II. New investigations with twice as many candidates
• AstroImageJ: Image Processing and Photometric Extraction for Ultra-Precise Astronomical Light Curves (Expanded Edition)
• AstroImageJ: Image Processing and Photometric Extraction for Ultra-Precise Astronomical Light Curves
• A Closely-Packed System of Low-Mass, Low-Density Planets Transiting Kepler-11
• Probabilistic Forecasting of the Masses and Radii of Other Worlds
• A Framework for Prioritizing the TESS Planetary Candidates Most Amenable to Atmospheric Characterization
• The Mass-Radius Relation for 65 Exoplanets Smaller than 4 Earth Radii
• The Transiting Exoplanet Survey Satellite: Simulations of planet detections and astrophysical false positives
• Improving the Efficiency of Markov Chain Monte Carlo for Analyzing the Orbits of Extrasolar Planets
• Characterizing transiting exoplanet atmospheres with JWST
• Terrestrial Planet Occurrence Rates for the Kepler GK Dwarf Sample
• PandExo: A Community Tool for Transiting Exoplanet Science with JWST & HST
• Binning is sinning: morphological light-curve distortions due to finite integration time
• A Revised Exoplanet Yield from the Transiting Exoplanet Survey Satellite (TESS)
• Probabilistic Mass-Radius Relationship for Sub-Neptune-Sized Planets
• EVEREST: Pixel Level Decorrelation of K2 Light curves
• The Habitable-Zone Planet Finder: A Stabilized Fiber-Fed NIR Spectrograph for the Hobby-Eberly Telescope
• Transit Timing Observations from Kepler. VIII Catalog of Transit Timing Measurements of the First Twelve Quarters
• Zodiacal Exoplanets In Time (ZEIT) I: A Neptune-sized planet orbiting an M4.5 dwarf in the Hyades Star Cluster
• Scientific Discovery with the James Webb Space Telescope
• Zodiacal Exoplanets in Time (ZEIT) IV: seven transiting planets in the Praesepe cluster
• EXPRES: A Next Generation RV Spectrograph in the Search for Earth-like Worlds
• On Correlated-noise Analyses Applied To Exoplanet Light Curves
• Trends in Atmospheric Properties of Neptune-Size Exoplanets
• An ultra-short period rocky super-Earth with a secondary eclipse and a Neptune-like companion around K2-141
• SPIRou: the near-infrared spectropolarimeter/high-precision velocimeter for the Canada-France-Hawaii telescope
• Spitzer Observations Confirm and Rescue the Habitable-Zone Super-Earth K2-18b for Future Characterization
• Exo-Transmit: An Open-Source Code for Calculating Transmission Spectra for Exoplanet Atmospheres of Varied Composition
• Towards Space-like Photometric Precision from the Ground with Beam-Shaping Diffusers
• Atmospheric Scintillation in Astronomical Photometry
• A Versatile Technique to Enable sub-milli-Kelvin Instrument Stability for Precise Radial Velocity Measurements: Tests with the Habitable-zone Planet Finder
• WASP-8b: Characterization of a Cool and Eccentric Exoplanet with Spitzer
• Ground-based optical transmission spectroscopy of the small, rocky exoplanet GJ 1132b
• K2 Discovers a Busy Bee: An Unusual Transiting Neptune Found in the Beehive Cluster
• Improving the Accuracy of Planet Occurrence Rates from Kepler using Approximate Bayesian Computation
• Thermal Emission of WASP-14b Revealed with Three Spitzer Eclipses
• astroplan: An Open Source Observation Planning Package in Python
• Planet Hunters. VIII. Characterization of 41 Long-Period Exoplanet Candidates from Kepler Archival Data
• Predicted Number, Multiplicity, and Orbital Dynamics of TESS M Dwarf Exoplanets
• Information Content Analysis for Selection of Optimal JWST Observing Modes for Transiting Exoplanet Atmospheres
• Two Small Planets Transiting HD 3167
• The discovery and mass measurement of a new ultra-short-period planet: EPIC~228732031b
• Two Small Transiting Planets and a Possible Third Body Orbiting HD 106315
• Ground-Based Submillimagnitude CCD Photometry of Bright Stars Using Snapshot Observations
• A Multi-Planet System Transiting the $V$ = 9 Rapidly Rotating F-Star HD 106315
• The K2-ESPRINT Project III: A Close-in Super-Earth around a Metal-rich Mid-M Dwarf
• Challenges to Constraining Exoplanet Masses via Transmission Spectroscopy
• Spitzer Observations of Exoplanets Discovered with The Kepler K2 Mission
• Know the Planet, Know the Star: Precise Stellar Densities from Kepler Transit Light Curves
• Ultra Short Period Planets in K2 with companions: a double transiting system for EPIC 220674823
• K2-114b and K2-115b: Two Transiting Warm Jupiters
• No Timing Variations Observed in Third Transit of Snow-Line Exoplanet Kepler-421b
• Confirmation of an exoplanet using the transit color signature: Kepler-418b, a blended giant planet in a multiplanet system
• Ground-based photometry of the 21-day Neptune HD106315c
• Angular correlation of the stellar scintillation on large telescopes
• Temperate super-Earths/mini-Neptunes around M/K dwarfs Consist of 2 Populations Distinguished by Their Atmospheres
• An Improved Transit Measurement for a 2.4 R_{Earth} Planet Orbiting A Bright Mid-M Dwarf K2$-$28

Cited by in corpus (17)

• The Habitable-zone Planet Finder Reveals A High Mass and a Low Obliquity for the Young Neptune K2-25b
• A sub-Neptune sized planet transiting the M2.5-dwarf G 9-40: Validation with the Habitable-zone Planet Finder
• Radial velocity confirmation of K2-100b: a young, highly irradiated, and low density transiting hot Neptune
• Diffuser-Assisted Infrared Transit Photometry for Four Dynamically Interacting \textit{Kepler} Systems
• Exploring Whether Super-Puffs Can Be Explained as Ringed Exoplanets
• Zodiacal Exoplanets in Time. X. The Orbit and Atmosphere of the Young "Neptune Desert"-Dwelling Planet K2-100b
• A warm Jupiter transiting an M dwarf: A TESS single transit event confirmed with the Habitable-zone Planet Finder
• The MOPYS project: A survey of 70 planets in search of extended He I and H atmospheres. No evidence of enhanced evaporation in young planets
• First Light of Engineered Diffusers at the Nordic Optical Telescope Reveal Time Variability in the Optical Eclipse Depth of WASP-12b
• The TEMPO Survey I: Predicting Yields of the Transiting Exosatellites, Moons, and Planets from a 30-day Survey of Orion with the Nancy Grace Roman Space Telescope
• Precovery of TESS Single Transits with KELT
• The unusual M-dwarf Warm Jupiter TOI-1899~b: Refinement of orbital and planetary parameters
• Detection capability of ground-based meter-sized telescopes for shallow exoplanet transits
• A Spectroscopic Analysis of a Sample of K2 Planet-Host Stars: Stellar Parameters, Metallicities and Planetary Radii
• Exoplanet Exploration Program Analysis Group (ExoPAG) Study Analysis Group (SAG) 17 Final Report Resources Needed for Planetary Confirmation and Characterization
• TYCHO -- Realistically Simulating Exoplanets within Stellar Clusters I: Improving the Monte Carlo Approach
• A Comparison of the Diffuser Method Versus the Defocus Method for Performing High-Precision Photometry with Small Telescope Systems