162 citations · 686 across the 11 of their papers we have counts for
10 papers
Atmospheric Temperature Inversions and He I 5876 Core Profile Structure in White Dwarfs
Beth Klein, Simon Blouin, Diego Romani +7
We report distinctive core profiles in the strongest optical helium line, He I 5876, from high-resolution high-sensitivity observations of spectral type DB white dwarfs. By analyzi…
The Chemical Composition of an Extrasolar Kuiper-Belt-Object
S. Xu, B. Zuckerman, P. Dufour +3
The Kuiper Belt of our solar system is a source of short-period comets that may have delivered water and other volatiles to Earth and the other terrestrial planets. However, the di…
Evidence for Gas from a Disintegrating Extrasolar Asteroid
S. Xu, M. Jura, P. Dufour +1
We report high-resolution spectroscopic observations of WD 1145+017 -- a white dwarf that recently has been found to be transitted by multiple asteroid-sized objects within its tid…
A Young White Dwarf with an Infrared Excess
S. Xu, M. Jura, B. Pantoja +4
Using observations of Spitzer/IRAC, we report the serendipitous discovery of excess infrared emission from a single white dwarf PG 0010+280. At a temperature of 27,220 K and a cool…
A Pilot Search for Evidence of Extrasolar Earth-analog Plate Tectonics
M. Jura, B. Klein, S. Xu +1
Relative to calcium, both strontium and barium are markedly enriched in Earth's continental crust compared to the basaltic crusts of other differentiated rocky bodies within the so…
Elemental Compositions of Two Extrasolar Rocky Planetesimals
S. Xu, M. Jura, D. Koester +2
We report Keck/HIRES and HST/COS spectroscopic studies of extrasolar rocky planetesimals accreted onto two hydrogen atmosphere white dwarfs, G29-38 and GD 133. In G29-38, 8 element…
26Al in the Early Solar System: Not so Unusual After All
M. Jura, S. Xu, E. D. Young
Recently acquired evidence shows that extrasolar asteroids exhibit over a factor of 100 variation in the iron to aluminum abundance ratio. This large range likely is a consequence…
Extrasolar Refractory-Dominated Planetesimals: an Assessment
M. Jura, S. Xu
Previously published observations of 60 externally-polluted white dwarfs show that none of the stars have accreted from intact refractory-dominated parent bodies composed mainly of…
Two Extrasolar Asteroids with Low Volatile-Element Mass Fractions
M. Jura, S. Xu, B. Klein +2
Using ultraviolet spectra obtained with the Cosmic Origins Spectrograph on the Hubble Space Telescope, we extend our previous ground-based optical determinations of the composition…
Water Fractions in Extrasolar Planetesimals
M. Jura, S. Xu
With the goal of using externally-polluted white dwarfs to investigate the water fractions of extrasolar planetesimals, we assemble from the literature a sample that we estimate to…