55 citations · 174 across the 11 of their papers we have counts for
11 papers
A Comprehensive Study of the Dust Declines in R Coronae Borealis Stars
Courtney L. Crawford, Jamie Soon, Geoffrey C. Clayton +4
The R Coronae Borealis (RCB) variables are rare, hydrogen-deficient, carbon-rich supergiants known for large, erratic declines in brightness due to dust formation. Recently, the nu…
Modelling Hydrogen-deficient Carbon stars in MESA -- The effects of total mass and mass ratio
Courtney L. Crawford, Nikita Nikultsev, Geoffrey C. Clayton +3
Hydrogen-deficient Carbon (HdC) stars are rare, low-mass, chemically peculiar, supergiant variables believed to be formed by a double white dwarf (DWD) merger, specifically of a Ca…
HdC and EHe stars through the prism of Gaia DR3: 3D distribution and Gaia's chromatic PSF effects
P. Tisserand, C. L. Crawford, J. Soon +3
Upon its release the Gaia DR3 catalogue has led to tremendous progress in multiple fields of astronomy by providing the complete astrometric solution for nearly 1.5 billion sources…
HdC and EHe stars through the prism of Gaia DR3: Evolution of RV amplitude and dust formation rate with effective temperature
P. Tisserand, C. L. Crawford, J. Soon +3
The Gaia DR3 release includes heliocentric radial velocity measurements and velocity variability indices for tens of millions of stars observed over 34 months.In this study, we uti…
TESS observations of the Pleiades cluster: a nursery for delta Scuti stars
Timothy R. Bedding, Simon J. Murphy, Courtney Crawford +8
We studied 89 A- and F-type members of the Pleiades open cluster, including five escaped members. We measured projected rotational velocities (v sin i) for 49 stars and confirmed t…
A Spectral Classification System for Hydrogen-deficient Carbon Stars
Courtney L. Crawford, Patrick Tisserand, Geoffrey C. Clayton +6
Stellar spectral classification has been highly useful in the study of stars. While there is a currently accepted spectral classification system for carbon stars, the subset of Hyd…
Peculiar Hydrogen-deficient Carbon Stars: Strontium-Rich Stars and the s-Process
Courtney L. Crawford, Patrick Tisserand, Geoffrey C. Clayton +1
Context: R Coronae Borealis (RCB) variables and their non-variable counterparts, the dustless Hydrogen-Deficient Carbon (dLHdC) stars have been known to exhibit enhanced s-processe…
The dawn of a new era for dustless HdC stars with GAIA eDR3
P. Tisserand, C. L. Crawford, G. C. Clayton +7
Decades after their discovery, only four hydrogen-deficient carbon (HdC) stars were known to have no circumstellar dust shell. This is in complete contrast to the 130 known G…
R Coronae Borealis Star Evolution: Simulating 3D Merger Events to 1D Stellar Evolution Including Large Scale Nucleosynthesis
Bradley Munson, Emmanouil Chatzopoulos, Juhan Frank +4
R Coronae Borealis (RCB) stars are rare hydrogen-deficient carbon-rich variable supergiants thought to be the result of dynamically unstable white dwarf mergers. We attempt to mode…
Modeling R Coronae Borealis Stars: Effects of He-Burning Shell Temperature and Metallicity
Courtney L. Crawford, Geoffrey C. Clayton, Bradley Munson +2
The R Coronae Borealis (RCB) stars are extremely hydrogen-deficient carbon stars which produce large amounts of dust, causing sudden deep declines in brightness. They are believed…
The Age of the Galactic Stellar Halo from Gaia White Dwarfs
Mukremin Kilic, P. Bergeron, Kyra Dame +3
We use 156 044 white dwarf candidates with significant parallax measurements from the Gaia mission to measure the velocity dispersion of the Galactic disc; $(σ_U,σ_V,σ_W)…