32 citations · 46 across the 5 of their papers we have counts for
6 papers
Evidence for neutron capture in heavy-metal hot subdwarfs: Far-UV spectroscopy of EC22536-5304 and LSIV-14 116
M. Dorsch, C. S. Jeffery, J. Deprince +8
Most hot subdwarfs (sdO/B) are low-mass core-helium-burning stars formed through binary interaction. A subgroup of intermediate He-rich sdOBs shows extreme heavy-metal (Z>30) enric…
TESS Observations of Stochastic Low-frequency Variability in Extreme Helium Stars
Courtney L. Crawford, C. Simon Jeffery, May G. Pedersen +4
Extreme helium stars (EHes) are low-mass hydrogen-deficient stars thought to be the products of double white dwarf mergers. Despite prolonged ground-based observations, there is no…
A 500 pc volume-limited sample of hot subluminous stars I. Space density, scale height, and population properties
H. Dawson, S. Geier, U. Heber +25
We present the first volume-limited sample of spectroscopically confirmed hot subluminous stars out to 500 pc, defined using the accurate parallax measurements from the {\em Gaia}…
Subaru and Swift observations of V652 Herculis: resolving the photospheric pulsation
C. S. Jeffery, D. Kurtz, H. Shibahashi +4
High resolution spectroscopy with the Subaru High Dispersion Spectrograph, and Swift ultraviolet photometry are presented for the pulsating extreme helium star V652\,Her. Swift pro…
Variable Stars
G. Handler, K. R. Pollard, M. S. Cunha +10
This is the triennial report of IAU Commission 27, mostly presenting a review of recent advances in the field.
Extreme helium stars: non-LTE matters Helium and hydrogen spectra of the unique objects V652 Her and HD144941
N. Przybilla, K. Butler, U. Heber +1
Quantitative analyses of low-mass hydrogen-deficient (super-)giant stars - so-called extreme helium stars - to date face two major difficulties. First, theory fails to reproduce th…