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Variable Emission from a Gaseous Disc around a Metal-Polluted White Dwarf (2015)
Conference Proceeding
Wilson, D. J., Gaensicke, B. T., Koester, D., Raddi, R., Breedt, E., Southworth, J., & Parsons, S. G. (2015). Variable Emission from a Gaseous Disc around a Metal-Polluted White Dwarf. In Vol. 493 – 19th European Workshop on White Dwarfs

We present the discovery of a variable gaseous disc around the metal-polluted DA white dwarf SDSS J1617+1620. Time-series spectroscopy obtained during the period 2006-2014 has shown the appearance of very strong double-peaked Ca ii 8600Å emission lin... Read More about Variable Emission from a Gaseous Disc around a Metal-Polluted White Dwarf.

DEBCat: A Catalog of Detached Eclipsing Binary Stars (2015)
Conference Proceeding
Southworth, J. (2015). DEBCat: A Catalog of Detached Eclipsing Binary Stars. In Astronomical Society of the Pacific Conference Series

Detached eclipsing binary star systems are our primary source of measured physical properties of normal stars. I introduce DEBCat: a catalogue of detached eclipsing binaries with mass and radius measurements to the 2% precision necessary to put usefu... Read More about DEBCat: A Catalog of Detached Eclipsing Binary Stars.

MUCHFUSS: Status and Highlights (2014)
Conference Proceeding
Geier, S., Kupfer, T., Barlow, B. N., Schaffenroth, V., Furst, F., Heuser, C., …Napiwotzki, R. (2014). MUCHFUSS: Status and Highlights.

The MUCHFUSS project aims at finding sdBs with massive compact companions. Here we report on the current status of our spectroscopic and photometric follow-up campaigns and present some highlight results. We derive orbital solutions of seven new sdB... Read More about MUCHFUSS: Status and Highlights.

Observational Studies of Transiting Extrasolar Planets (2014)
Conference Proceeding
Southworth, J. (2014). Observational Studies of Transiting Extrasolar Planets. In Living Together: planets, host stars and binaries (321 -336)

The study of transiting extrasolar planets is only 15 years old, but has matured into a rich area of research. I review the observational aspects of this work, concentrating on the discovery of transits, the characterization of planets from photometr... Read More about Observational Studies of Transiting Extrasolar Planets.

Mapping the Star Formation in Orion A/L1641 (2014)
Conference Proceeding
Pillitteri, I., Wolk, S. J., Megeath, S. T., Allen, L., Bally, J., Gagné, M., …Stauffer, J. (2014). Mapping the Star Formation in Orion A/L1641. In The Labyrinth of Star Formation (291-293). https://doi.org/10.1007/978-3-319-03041-8_56

First phases of the process of star formation are characterized by excess in infrared and high X-ray emission. With Spitzer and XMM-Newton we have surveyed the Orion A part relative to the filamentary cloud Lynds 1641 (L1641). Furthermore, an extende... Read More about Mapping the Star Formation in Orion A/L1641.

Discovery of the Closest Hot Subdwarf Binary with White Dwarf Companion (2013)
Conference Proceeding
Geier, S., Marsh, T. R., Dunlap, B. H., Barlow, B. N., Schaffenroth, V., Ziegerer, E., …Napiwotzki, R. (2013). Discovery of the Closest Hot Subdwarf Binary with White Dwarf Companion. In 18th European White Dwarf Workshop (EUROWD12) (373)

We report the discovery of an extremely close, eclipsing binary system. A white dwarf is orbited by a core He-burning compact hot subdwarf star with a period as short as ≃ 0.04987 d making this system the most compact hot subdwarf binary discovered s... Read More about Discovery of the Closest Hot Subdwarf Binary with White Dwarf Companion.

The Chemical Evolution of Heavy Elements in Globular Clusters (2013)
Conference Proceeding
Shingles, L. J., Karakas, A. I., & Hirschi, R. (2013). The Chemical Evolution of Heavy Elements in Globular Clusters. . https://doi.org/10.1017/s1743921313007059

We present preliminary results from a chemical evolution model that tracks the composition of heavy elements beyond iron in a globular cluster. The heavy elements can be used as tracers of the nucleosynthetic events that defined the formation and evo... Read More about The Chemical Evolution of Heavy Elements in Globular Clusters.

HSTEP -- Homogeneous Studies of Transiting Extrasolar Planets (2012)
Conference Proceeding
Southworth, J. (2012). HSTEP -- Homogeneous Studies of Transiting Extrasolar Planets. . https://doi.org/10.1017/S174392131301332X

I give a summary of the HSTEP project: an effort to calculate the physical properties of the known transiting extrasolar planets using a homogeneous approach. I discuss the motivation for the project, list the 83 planets which have already been studi... Read More about HSTEP -- Homogeneous Studies of Transiting Extrasolar Planets.

Eclipsing Binary Stars: the Royal Road to Stellar Astrophysics (2012)
Conference Proceeding
Taylor. (2012). Eclipsing Binary Stars: the Royal Road to Stellar Astrophysics. In Proceedings of the workshop "Orbital Couples: Pas de Deux in the Solar System and the Milky Way" (51-58)

Russell (1948) famously described eclipses as the "royal road" to stellar astrophysics. From photometric and spectroscopic observations it is possible to measure the masses and radii (to 1% or better!), and thus surface gravities and mean densities,... Read More about Eclipsing Binary Stars: the Royal Road to Stellar Astrophysics.

The impact of reduced mass loss rates on the evolution of massive stars (2008)
Conference Proceeding
Hirschi, R. (2008). The impact of reduced mass loss rates on the evolution of massive stars.

Mass loss is a very important aspect of the life of massive stars. After briefly reviewing its importance, we discuss the impact of the recently proposed downward revision of mass loss rates due to clumping (difficulty to form Wolf-Rayet stars and pr... Read More about The impact of reduced mass loss rates on the evolution of massive stars.

Developments in physics of massive stars (2007)
Conference Proceeding
Meynet, G., Ekström, S., Maeder, A., Hirschi, R., Georgy, C., & Beffa, C. (2007). Developments in physics of massive stars. . https://doi.org/10.1017/S1743921308020449

New constraints on stellar models are provided by large surveys of massive stars, interferometric observations and asteroseismology. After a review of the main results so far obtained, we present new results from rotating models and discuss compariso... Read More about Developments in physics of massive stars.

Rotating massive stars @ very low Z: high C and N production (2006)
Conference Proceeding
Hirschi, R. (2006). Rotating massive stars @ very low Z: high C and N production. . https://doi.org/10.1063/1.2234385

Two series of models and their yields are presented in this paper. The first series consists of 20 Mo models with varying initial metallicity (solar down to $Z=10^{-8}$) and rotation (Vini=0-600 km/s). The second one consists of models with an initia... Read More about Rotating massive stars @ very low Z: high C and N production.

Pre-suprenova evolution of rotating massive stars (2005)
Conference Proceeding
Hirschi, R., Meynet, G., Maeder, A., & Goriely, S. (2005). Pre-suprenova evolution of rotating massive stars. . https://doi.org/10.1007/3-540-26633-X_28

The Geneva evolutionary code has been modified to study the advanced stages (Ne, O, Si burnings) of rotating massive stars. Here we present the results of four 20 solar mass stars at solar metallicity with initial rotational velocities of 0, 100, 200... Read More about Pre-suprenova evolution of rotating massive stars.

Young stars and their circumstellar disks in the Sigma Orionis cluster (2004)
Conference Proceeding
M. Oliveira, J., D. Jeffries, R., Th. van Loon, J., & J. Kenyon, M. (2004). Young stars and their circumstellar disks in the Sigma Orionis cluster. In Open Issues in Local Star Formation (55–62). https://doi.org/10.1007/1-4020-2600-5_6

The sigma Orionis cluster is a young association evolving under the disruptive influence of its massive O-star namesake. We are analysing this cluster as part of a program to characterise the influence of O-stars on the early stages of stellar evolut... Read More about Young stars and their circumstellar disks in the Sigma Orionis cluster.

Eclipsing binaries in open clusters (2003)
Conference Proceeding
Southworth, J., Maxted, P., & Smalley, B. (2003). Eclipsing binaries in open clusters.

Accurate physical parameters have been determined for two early-type detached eclipsing binaries in the open cluster h Persei (NGC 869). Masses accurate to 1.5% are derived from high-resolution spectroscopy and radii accurate to 4--6% have been obtai... Read More about Eclipsing binaries in open clusters.

Evolution and Nucleosynthesis of Massive Stars
Conference Proceeding
Meynet, G., Maeder, A., Choplin, A., Takahashi, K., Ekström, S., Hirschi, R., …Eggenberger, P. (2017). Evolution and Nucleosynthesis of Massive Stars. . https://doi.org/10.7566/jpscp.14.010401

Massive stars are rapid nuclear reactors that play a key role in injecting new synthesized elements in the interstellar medium. Depending on the strengths of the stellar winds on the efficiency of mixing processes, the masses and the chemical composi... Read More about Evolution and Nucleosynthesis of Massive Stars.

Production Uncertainties of p-Nuclei in the γ-Process in Massive Stars Using a Monte Carlo Approach
Conference Proceeding
Rauscher, T., Nishimura, N., Hirschi, R., Cescutti, G., Murphy, A. S. J., & Heger, A. (2017). Production Uncertainties of p-Nuclei in the γ-Process in Massive Stars Using a Monte Carlo Approach. In Proceedings of the 14th International Symposium on Nuclei in the Cosmos (NIC2016). https://doi.org/10.7566/jpscp.14.010509

Proton-rich nuclei, the so-called p-nuclei, are made in photodisintegration processes in outer shells of massive stars in the course of the final supernova explosion. Nuclear uncertainties in the production of these nuclei have been quantified in a M... Read More about Production Uncertainties of p-Nuclei in the γ-Process in Massive Stars Using a Monte Carlo Approach.

The curious case of Betelgeuse
Conference Proceeding
van Loon, J. T. (2023). The curious case of Betelgeuse. In The Sixteenth Marcel Grossmann Meeting On Recent Developments in Theoretical and Experimental General Relativity, Astrophysics, and Relativistic Field Theories (In 4 Volumes). https://doi.org/10.1142/9789811269776_0289

Betelgeuse is the nearest red supergiant, one of the brightest stars in our sky, and statistically speaking it would be expected to be “typical”. Yet it exhibits many features that seem “curious”, to say the least. For instance it has a high proper m... Read More about The curious case of Betelgeuse.