Publications (15)
Helium abundances and the helium isotope anomaly of sdB stars
S. Geier, U. Heber, H. Edelmann +5
Helium abundances and atmospheric parameters have been determined from high resolution spectra for a new sample of 46 bright hot subdwarf B (sdB) stars. The helium abundances have…
The optical afterglow of the short gamma-ray burst associated with GW170817
J. D. Lyman, G. P. Lamb, A. J. Levan +33
The binary neutron star merger GW170817 was the first multi-messenger event observed in both gravitational and electromagnetic waves. The electromagnetic signal began approximately…
The evolutionary status of Cataclysmic Variables: Eclipse modelling of 15 systems
M. McAllister, S. P. Littlefair, S. G. Parsons +13
We present measurements of the component masses in 15 Cataclysmic Variables (CVs) - 6 new estimates and 9 improved estimates. We provide new calibrations of the relationship betwee…
Illuminating Gravitational Waves: A Concordant Picture of Photons from a Neutron Star Merger
M. M. Kasliwal, E. Nakar, L. P. Singer +78
Merging neutron stars offer an exquisite laboratory for simultaneously studying strong-field gravity and matter in extreme environments. We establish the physical association of an…
Optical photometry and spectroscopy of the low-luminosity, broad-lined Ic supernova iPTF15dld
E. Pian, L. Tomasella, E. Cappellaro +37
Core-collapse stripped-envelope supernova (SN) explosions reflect the diversity of physical parameters and evolutionary paths of their massive star progenitors. We have observed th…
White paper: Gaia and the end states of stellar evolution
M. A Barstow, S. L. Casewell, S. Catalan +18
This is the product of a Gaia GREAT workshop on "Gaia and the end states of stellar evolution" held at the University of Leicester in April 2011.
Massive unseen companions to hot faint underluminous stars from SDSS (MUCHFUSS) - Analysis of seven close subdwarf B binaries
S. Geier, P. F. L. Maxted, R. Napiwotzki +12
The project Massive Unseen Companions to Hot Faint Underluminous Stars from SDSS (MUCHFUSS) aims at finding hot subdwarf stars with massive compact companions like massive white dw…
Total eclipse of the heart: The AM CVn Gaia14aae / ASSASN-14cn
H. C. Campbell, T. R. Marsh, M. Fraser +82
We report the discovery and characterisation of a deeply eclipsing AM CVn-system, Gaia14aae (= ASSASN-14cn). Gaia14aae was identified independently by the All-Sky Automated Survey…
Optical variability of the ultracool dwarf TVLM 513-46546: evidence for inhomogeneous dust clouds
S. P. Littlefair, V. S. Dhillon, T. R. Marsh +3
We present multi-colour photometry of the M8.5V ultracool dwarf "pulsar" TVLM 513-46546 (hereafter TVLM 513) obtained with the triple-beam photometer ULTRACAM. Data were obtained s…
Testing the planetary models of HU Aquarii
M. Bours, T. Marsh, E. Breedt +6
We present new eclipse observations of the polar (i.e. semi-detached magnetic white dwarf + M-dwarf binary) HU Aqr, and mid-egress times for each eclipse, which continue to be obse…
The 4 meter New Robotic Telescope project: an updated report
C. M. Gutiérrez, M. Torres, A. Oria +23
The New Robotic Telescope (NRT) is an international collaboration to build and operate a 4 m diameter fully robotic telescope. The telescope will take advantage of the superb atmos…
Hunting high and low: XMM monitoring of the eclipsing polar HU Aquarii
R. Schwarz, A. D. Schwope, J. Vogel +5
We want to study the temporal and spectral behaviour of HU Aqr in the X-ray domain during different accretion states. We obtained spectra and light curves from four different XMM-N…
A gravitational-wave standard siren measurement of the Hubble constant
B. P. Abbott, R. Abbott, T. D. Abbott +1308
The detection of GW170817 in both gravitational waves and electromagnetic waves heralds the age of gravitational-wave multi-messenger astronomy. On 17 August 2017 the Advanced LIGO…
On the evolutionary status of short period cataclysmic variables
S. P. Littlefair, V. S. Dhillon, T. R. Marsh +5
(Abridged) We present high-speed, three-colour photometry of seven short period (Porb <= 95 mins) eclipsing CVs from the Sloan Digital Sky Survey. We determine the system parameter…
Hot subdwarf stars in close-up view IV. Helium abundances and the He isotopic anomaly of subdwarf B star
S. Geier, U. Heber, H. Edelmann +5
Atmospheric parameters and helium abundances of 44 bright subdwarf B stars have been determined. More than half of our sample consists of newly discovered stars from the Edinburgh…