Publications (33)
A Keck Adaptive Optics Search for Young Extrasolar Planets
Denise Kaisler, Ben Zuckerman, Eric Becklin +1
Adaptive optics, large primary mirrors, and careful selection of target stars are the keys to ground-based imaging of extrasolar planets. Our near-IR survey is capable of identifyi…
The nearby, young, isolated, dusty star HD 166191
Adam Schneider, Inseok Song, Carl Melis +4
We report an in-depth study of the F8-type star HD 166191, identified in an ongoing survey for stars exhibiting infrared emission above their expected photospheres in the Wide-fiel…
Oxygen fugacities of extrasolar rocks: Evidence for an Earth-like geochemistry of exoplanets
Alexandra E. Doyle, Edward D. Young, Beth Klein +2
Oxygen fugacity is a measure of rock oxidation that influences planetary structure and evolution. Most rocky bodies in the Solar System formed at oxygen fugacities approximately fi…
Hunting the Coolest Dwarfs: Methods and Early Results
Adam Schneider, Carl Melis, Inseok Song +1
We present the methods and first results of a survey of nearby high proper motion main sequence stars to probe for cool companions with the Gemini camera at Lick Observatory. This…
Oumuamua Is Not a Probe Sent to our Solar System by an Alien Civilization
Ben Zuckerman
Oumuamua, the first known object of extrasolar origin seen to enter our Solar System, has multiple unusual characteristics that, taken together, are very difficult to explain with…
Keck adaptive optics observations of TW Hydrae Association members
Bruce Macintosh, Claire Max, Ben Zuckerman +7
Adaptive optics (AO) on 8-10 m telescopes is an enormously powerful tool for studying young nearby stars. It is especially useful for searching for companions. Using AO on the 10-m…
Identifying Nearby, Young, Late-type Stars by Means of Their Circumstellar Disks
Adam Schneider, Inseok Song, Carl Melis +2
It has recently been shown that a significant fraction of late-type members of nearby, very young associations (age <10 Myr) display excess emission at mid-IR wavelengths indicativ…
A Giant Planet Candidate Transiting a White Dwarf
Andrew Vanderburg, Saul A. Rappaport, Siyi Xu +61
Astronomers have discovered thousands of planets outside the solar system, most of which orbit stars that will eventually evolve into red giants and then into white dwarfs. During…
The bulk composition of exo-planets
Boris Gaensicke, John Debes, Patrick Dufour +7
Priorities in exo-planet research are rapidly moving from finding planets to characterizing their physical properties. Of key importance is their chemical composition, which feeds…
An emerging and enigmatic spectral class of isolated DAe white dwarfs
Abbigail K. Elms, Pier-Emmanuel Tremblay, Boris T. Gänsicke +9
Two recently discovered white dwarfs, WDJ041246.84754942.26 and WDJ165335.21100116.33, exhibit H and H Balmer line emission similar to stars in the emerging DAHe clas…
The Wide Brown Dwarf Binary Oph 1622-2405 and Discovery of A Wide, Low Mass Binary in Ophiuchus (Oph 1623-2402): A New Class of Young Evaporating Wide Binaries?
Laird M. Close, Ben Zuckerman, Inseok Song +10
We imaged five objects near the star forming clouds of Ophiuchus with the Keck Laser Guide Star AO system. We resolved Allers et al. (2006)'s #11 (Oph 16222-2405) and #16 (Oph 1623…
Extent of Excess Far Infrared Emission around Luminosity Class III Stars
Sungsoo S. Kim, Ben Zuckerman, Murray Silverstone
With the Infrared Space Observatory, we conducted 3x3-pixel imaging photometry of twelve luminosity class III stars, which were previously presumed to have dust particles around th…
The Gemini Planet Imager view of the HD 32297 debris disk
Gaspard Duchene, Malena Rice, Justin Hom +60
We present new -band scattered light images of the HD 32297 edge-on debris disk obtained with the Gemini Planet Imager (GPI). The disk is detected in total and polarized intensi…
A Machine-Learning Compositional Study of Exoplanetary Material Accreted Onto Five Helium-Atmosphere White Dwarfs with
Mariona Badenas-Agusti, Siyi Xu, Andrew Vanderburg +8
We present the first application of the Machine Learning (ML) pipeline to determine the physical parameters and photospheric composition of five metal-polluted H…
Astro 2020 Science White Paper: Evolved Planetary Systems around White Dwarfs
Boris Gaensicke, Martin Barstow, Amy Bonsor +25
Practically all known planet hosts will evolve into white dwarfs, and large parts of their planetary systems will survive this transition - the same is true for the solar system be…
Shallow Ultraviolet Transits of WD 1145+017
Siyi Xu, Na'ama Hallakoun, Bruce Gary +16
WD 1145+017 is a unique white dwarf system that has a heavily polluted atmosphere, an infrared excess from a dust disk, numerous broad absorption lines from circumstellar gas, and…
Young Stars Near Earth: The Octans-Near Association and Castor Moving Group
Ben Zuckerman, Laura Vican, Inseok Song +1
All cataloged stellar moving groups and associations with ages <100 Myr and within 100 pc of Earth have Galactic space motions (UVW) situated in a "good box" with dimensions ~20 km…
Debris Disk Results from the Gemini Planet Imager Exoplanet Survey's Polarimetric Imaging Campaign
Thomas M. Esposito, Paul Kalas, Michael P. Fitzgerald +62
We report the results of a -year direct imaging survey of 104 stars to resolve and characterize circumstellar debris disks in scattered light as part of the Gemini Planet…
New Members of the Scorpius Centaurus Complex and Ages of its sub-regions
Inseok Song, Ben Zuckerman, Mike Bessell
We have spectroscopically identified about 100 G-, K- and M-type members of the Scorpius Centaurus complex. To deduce the age of these young stars we compare their Li 6708 abso…
The Early Evolution of Stars and Exoplanet Systems: Exploring and Exploiting Nearby, Young Stars (an Astro2020 Science White Paper)
Joel H. Kastner, Katelyn Allers, Brendan Bowler +12
Our knowledge of the population of young (age <=750 Myr) stars that lie within ~120 pc of the Sun is rapidly accelerating. The vast majority of these nearby, young stars can be pla…
Resolving debris discs in the far-infrared: early highlights from the DEBRIS survey
DEBRIS Collaboration, Brenda Matthews, Bruce Sibthorpe +30
We present results from the earliest observations of DEBRIS, a Herschel Key Programme to conduct a volume- and flux-limited survey for debris discs in A-type through M-type stars.…
Spectroscopic Observations of the Galex Nearby Young Star Survey Sample. 1. Nearby Moving Group Candidates
Navya Nagananda, Laura Vican, Ben Zuckerman +3
The GALEX Nearby Young Star Search (GALNYSS) yielded the identification of more than 2000 late-type stars that, based on their ultraviolet and infrared colors and pre-Gaia proper m…
First Resolved Scattered-Light Images of Four Debris Disks in Scorpius-Centaurus with the Gemini Planet Imager
Justin Hom, Jennifer Patience, Thomas M. Esposito +57
We present the first spatially resolved scattered-light images of four debris disks around members of the Scorpius-Centaurus (Sco-Cen) OB Association with high-contrast imaging and…
Minimal conditions for survival of technological civilizations in the face of stellar evolution
Brad Hansen, Ben Zuckerman
The ease of interstellar rocket travel is an issue with implications for the long term fate of our own and other civilizations and for the much-debated number of technological civi…
The International Deep Planet Survey II: The frequency of directly imaged giant exoplanets with stellar mass
Raphael Galicher, Christian Marois, Bruce Macintosh +8
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 b…
Fomalhaut b: Independent Analysis of the Hubble Space Telescope Public Archive Data
Raphael Galicher, Christian Marois, Ben Zuckerman +1
The nature and even the existence of a putative planet-mass companion ("Fomalhaut b") to Fomalhaut has been debated since 2008. In the present paper we reanalyze the multi-epoch AC…
Ejection of material --"Jurads" -- from post main sequence planetary systems
Brad Hansen, Ben Zuckerman
We show that the rate of pollution of white dwarfs by asteroidal material implies a concomitant rate of material ejection that can contribute significantly to the population of int…
The Ultra Cool Brown Dwarf Companion of WD 0806-661: Age, Mass, and Formation Mechanism
David R. Rodriguez, Ben Zuckerman, Carl Melis +1
We have combined multi-epoch images from the Infrared Side Port Imager on the CTIO 4-meter telescope to derive a 3-sigma limit of J=21.7 for the ultra cool brown dwarf companion to…
The Minimum Jeans Mass, Brown Dwarf Companion IMF, and Predictions for Detection of Y-type Dwarfs
Ben Zuckerman, Inseok Song
Cool L- and T-type objects were discovered first as companions to stars in 1988 and 1995, respectively. A certain example of the yet cooler Y-type spectral class (Teff <~ 500K?) ha…
Exocometary Science
Luca MatrÃ, Quentin Kral, Kate Su +20
Evidence for exocomets, icy bodies in extrasolar planetary systems, has rapidly increased over the past decade. Volatiles are detected through the gas that exocomets release as the…
SONS: The JCMT legacy survey of debris discs in the submillimetre
Wayne S. Holland, Brenda C. Matthews, Grant M. Kennedy +32
Debris discs are evidence of the ongoing destructive collisions between planetesimals, and their presence around stars also suggests that planets exist in these systems. In this pa…
Keck/NIRC2 '-Band Imaging of Jovian-Mass Accreting Protoplanets around PDS 70
Jason J. Wang, Sivan Ginzburg, Bin Ren +42
We present '-band imaging of the PDS 70 planetary system with Keck/NIRC2 using the new infrared pyramid wavefront sensor. We detected both PDS 70 b and c in our images, as well…
Silicate mineralogy and bulk composition of exoplanetary material in polluted white dwarfs
Laura K. Rogers, Amy Bonsor, Ãrika Le Bourdais +10
White dwarf planetary systems uniquely link the bulk elemental composition of exoplanetary material to the mineralogy as photospheric abundances can be compared to circumstellar du…