A5053135782- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astro and Planetary Science
- Astrophysics and Star Formation Studies
- Gamma-ray bursts and supernovae
- Geophysics and Gravity Measurements
- Astronomical Observations and Instrumentation
- Space Exploration and Technology
- Pulsars and Gravitational Waves Research
- Atmospheric and Environmental Gas Dynamics
- Atmospheric Ozone and Climate
- Geomagnetism and Paleomagnetism Studies
- Magnetic Properties of Alloys
- Calibration and Measurement Techniques
- Spectroscopy and Laser Applications
- Planetary Science and Exploration
- High-pressure geophysics and materials
- Adaptive optics and wavefront sensing
- Scientific Research and Discoveries
- Solar and Space Plasma Dynamics
- Characterization and Applications of Magnetic Nanoparticles
- Spacecraft and Cryogenic Technologies
- Scientific Computing and Data Management
- Solidification and crystal growth phenomena
- Health Policy Implementation Science
Space Science Institute
2019-2022
Space Telescope Science Institute
2017-2020
Planetary Systems (United States)
2019
Max Planck Institute for Astronomy
2018
University of Arizona
2016-2017
University of Maryland, College Park
2012-2015
California Institute of Technology
2014
Pontificia Universidad Católica de Chile
2014
Kitt Peak National Observatory
2012
22q11 Ireland
2012
Results from the Kepler mission indicate that occurrence rate of small planets ($<3$ $R_\oplus$) in habitable zone nearby low-mass stars may be as high 80%. Despite this abundance, probing conditions and atmospheric properties on any habitable-zone planet is extremely difficult has remained elusive to date. Here, we report detection water vapor likely presence liquid icy clouds atmosphere $2.6$ $R_\oplus$ K2-18b. The simultaneous mid-atmosphere K2-18b particularly intriguing because receives...
HAT-P-20b is a giant metal-rich exoplanet orbiting star. We analyze two secondary eclipses of the planet in each 3.6 and 4.5 μm bands Warm Spitzer. have developed simple, powerful, radically different method to correct intra-pixel effect for Spitzer data, which we call pixel-level decorrelation (PLD). PLD corrects very effectively, but without explicitly using—or even measuring—the fluctuations apparent position stellar image. illustrate validate using synthetic real data comparing results...
ABSTRACT GJ 1214b is the most studied sub-Neptune exoplanet to date. Recent measurements have shown its near-infrared transmission spectrum be flat, pointing a high-altitude opacity source in exoplanet's atmosphere, either equilibrium condensate clouds or photochemical hazes. Many photometric observations been reported optical by different groups, though simultaneous spanning entire regime are lacking. We present an (4500–9260 Å) of 14 bins, measured with Magellan /IMACS repeatedly over...
The short period ($0.94$-day) transiting exoplanet WASP-19b is an exceptional target for transmission spectroscopy studies, due to its relatively large atmospheric scale-height ($\sim 500$ km) and equilibrium temperature 2100$ K). Here we report on six precise spectroscopic Magellan/IMACS observations, five of which the full optical window from $0.45-0.9μ$m one targeting $0.4-0.55μ$m blue-optical range. Five these datasets are consistent with a spectrum without any significant spectral...
The James Webb Space Telescope (JWST) presents the opportunity to transform our understanding of planets and origins life by revealing atmospheric compositions, structures, dynamics transiting exoplanets in unprecedented detail. However, high-precision, timeseries observations required for such investigations have unique technical challenges, prior experience with Hubble, Spitzer, other facilities indicates that there will be a steep learning curve when JWST becomes operational. In this...
The James Webb Space Telescope (JWST) will likely revolutionize transiting exoplanet atmospheric science, due to a combination of its capability for continuous, long duration observations and larger collecting area, spectral coverage, resolution compared existing space-based facilities. However, it is unclear precisely how well JWST perform which myriad instruments observing modes be best suited studies. In this article, we describe prefatory Early Release Science (ERS) Cycle 1 program that...
We observed the transiting super-Earth exoplanet GJ1214b using warm Spitzer at 4.5 μm wavelength during a 20 day quasi-continuous sequence in 2011 May. The goals of our long observation were to accurately define infrared transit radius this nearby super-Earth, search for secondary eclipse, and other planets habitable zone GJ1214. here report results from monitoring GJ1214b, including reanalysis previous observations by Désert et al. In total, we analyze 14 transits μm, 3 3.6 7 new...
We report 78 secondary eclipse depths for a sample of 36 transiting hot Jupiters observed at 3.6- and 4.5 microns using the Spitzer Space Telescope. Our results 27 these planets are new, include highly irradiated worlds such as KELT-7b, WASP-87b, WASP-76b, WASP-64b, important targets JWST WASP-62b. find that WASP-62b has slightly eccentric orbit e cos(omega) = 0.00614+/- 0.00064, we confirm eccentricity HAT-P-13b WASP-14b. The remainder individually consistent with circular orbits, but...
We observe two secondary eclipses of the strongly irradiated transiting planet WASP-33b, in Ks band at 2.15 μm, and one eclipse each 3.6 μm 4.5 using Warm Spitzer. This orbits an A5V δ-Scuti star that is known to exhibit low-amplitude non-radial p-mode oscillations about 0.1% semi-amplitude. detect stellar all our infrared data, also night observations J (1.25 μm) out eclipse. The oscillation amplitude, bands except Ks, same as optical. However, (2.15 have twice amplitude (0.2%) seen...
GJ 1214b is the most studied sub-Neptune exoplanet to date. Recent measurements have shown its near-infrared transmission spectrum be flat, pointing a high-altitude opacity source in exoplanet's atmosphere, either equilibrium condensate clouds or photochemical hazes. Many photometric observations been reported optical by different groups, though simultaneous spanning entire regime are lacking. We present an (4500–9260 Å) of 14 bins, measured with Magellan/IMACS repeatedly over three...
We obtained J-, H-, and JH-band photometry of known extrasolar planet transiting systems at the 2.1 m Kitt Peak National Observatory Telescope using FLAMINGOS infrared camera between 2008 October 2011 October. From derived light curves we have extracted midtransit times, transit depths durations for these events. The precise times help improve orbital periods also constrain transit-time variations systems. For most cases published system parameters successfully accounted our observed curves,...
High-precision eclipse spectrophotometry of transiting terrestrial exoplanets represents a promising path for the first atmospheric characterizations habitable worlds and search life outside our solar system. The detection planets nearby late-type M-dwarfs could make this approach applicable within next decade, with soon-to-come general facilities. In context, we previously identified GJ 1214 as high-priority target transit search, probability planet orbiting M4.5 dwarf would be...
Atmospheric temperature and planetary gravity are thought to be the main parameters affecting cloud formation in giant exoplanet atmospheres. Recent attempts understand have explored wide regions of equilibrium temperature-gravity parameter space. In this study, we instead compare case two planets with nearly identical ($T_\mathrm{eq}$ $\sim 1050 \, \mathrm{K}$) ($g \sim 10 \mathrm{m s}^{-1})$. During $HST$ Cycle 23, collected WFC3/G141 observations planets, WASP-67 b HAT-P-38 b. b, mass...
Transmission spectroscopy provides a window to study exoplanetary atmospheres, but that is fogged by clouds and hazes. Clouds haze introduce degeneracy between the strength of gaseous absorption features planetary physical parameters such as abundances. One way break via statistical studies. We collect all published HST/WFC3 transit spectra for 1.1-1.65 $\mu$m water vapor absorption, perform on potential correlations feature parameters. fit observed with template calculated each planet using...
As part of the PanCET program, we have conducted a spectroscopic study WASP-79b, an inflated hot Jupiter orbiting F-type star in Eridanus with period 3.66 days. Building on original WASP and TRAPPIST photometry Smalley et al (2012), examine HST/WFC3 (1.125 - 1.650 $\mu$m), Magellan/LDSS-3C (0.6 1 $\mu$m) data, Spitzer data (3.6 4.5 $\mu$m). Using from all three instruments, constrain water abundance to be --2.20 $\leq$ log(H$_2$O) --1.55. We present these results along atmospheric retrieval...
Abstract We present observations of WASP-63b by the Hubble Space Telescope (HST) as part “A Preparatory Program to Identify Single Best Transiting Exoplanet for James Webb ( JWST ) Early Release Science (ERS).” is one community targets under consideration ERS program. a spectrum derived from single observation HST Wide Field Camera 3 in near-infrared. engaged groups across transiting exoplanet participate analysis data and results each. Extraction transmission several independent analyses...
Optical, reflected light eclipse observations provide a direct probe of the exoplanet scattering properties, such as from aerosols. We present here photometric, WASP-43b using HST WFC3/UVIS instrument with F350LP filter (346-822nm) encompassing entire optical band. This is first light, photometric UVIS in scanning mode; we further detail our extraction and analysis pipeline Arctor. Our curve for WASP-43 b derived 3-{\sigma} upper limit 67 ppm on depth, which implies that has very dark...
The James Webb Space Telescope (JWST) offers unprecedented sensitivity, stability, and wavelength coverage for transiting exoplanet studies, opening up new avenues measuring atmospheric abundances, structure, temperature profiles. Taking full advantage of JWST spectroscopy planets from 0.6 to 28 μm, however, will require many observations with a combination the NIRISS, NIRCam, NIRSpec, MIRI instruments. In this white paper, we discuss NIRCam mode (not yet approved or implemented) that can...
The interpretation of astronomical photometry, astrometry, and orbit determination data depends on accurately consistently identifying the center target object's photometric point spread function in presence noise. We introduce a new technique, called least asymmetry, which is designed to find about distribution most symmetric. This addition commonly used techniques Gaussian fitting light, was tested against synthetic datasets under realistic ranges noise gain. With subpixel accuracy, we...
Stellar activity is one of the main obstacles to high-precision exoplanet observations and has motivated extensive studies in detection characterization problems. Most efforts focused on unocculted starspots optical transit spectrophotometry, while impact starspot crossings assumed be negligible near-infrared. Here, we present \textit{HST}/WFC3 active star WASP-52, hosting an inflated hot Jupiter, which a possible occultation signal. By using this data set as benchmark, investigated whether...
KIC 12557548 b is first of a growing class intriguing disintegrating planet candidates, which lose mass in the form metal rich vapor that condenses into dust particles. Here, we follow up two perplexing observations system: 1) transits appeared shallower than average 2013 and 2014 2) parameters derived from high resolution spectrum star differed other results using photometry low spectroscopy. We observe 5 system with 61-inch Kuiper telescope 2016 show they are consistent Kepler spacecraft...
Transiting exoplanets orbiting active stars frequently occult starspots and faculae on the visible stellar disc. Such occultations are often rejected from spectrophotometric transits, as it is assumed they do not contain relevant information for study of exoplanet atmopsheres. However, can provide useful constraints to retrieve temperature features their effect transmission spectra. We analyse capabilities James Webb Space Telescope in determination spectra occulted starspots, despite its...