A rapidly spinning supermassive black hole at the centre of NGC?1365. (2013)
Journal Article
(2013). A rapidly spinning supermassive black hole at the centre of NGC?1365. Nature, 449 - 451. https://doi.org/10.1038/nature11938

Broad X-ray emission lines from neutral and partially ionized iron observed in active galaxies have been interpreted as fluorescence produced by the reflection of hard X-rays off the inner edge of an accretion disk. In this model, line broadening and... Read More about A rapidly spinning supermassive black hole at the centre of NGC?1365..

Intrinsic magnetism in nanosheets of SnO2: A first-principles study (2013)
Journal Article
Abreu Da Silva Morbec. (2013). Intrinsic magnetism in nanosheets of SnO2: A first-principles study. Journal of Magnetism and Magnetic Materials, 104 -108. https://doi.org/10.1016/j.jmmm.2012.10.017

We propose intrinsic magnetism in nanosheets of SnO2, based on first-principles calculations. The electronic structure and spin density reveal that p orbitals of the oxygen atoms, surrounding Sn vacancies, have a non-itinerant nature which gives birt... Read More about Intrinsic magnetism in nanosheets of SnO2: A first-principles study.

Band-gap profiling by laser writing of hydrogen-containing III-N-Vs (2012)
Journal Article
Martelli, F., Patanè, A., Rubini, S., Balakrishnan, N., Pettinari, G., Makarovsky, O., Turyanska, L., Fay, M., De Luca, M., Polimeni, A., & Capizzi, M. (2012). Band-gap profiling by laser writing of hydrogen-containing III-N-Vs. Physical review B: Condensed matter and materials physics, https://doi.org/10.1103/PhysRevB.86.155307

We show that the dissociation of the N-H complex in hydrogenated III-N-Vs can be laser activated at temperatures that are significantly smaller than those (>200?°C) required for thermal dissociation due to a resonant photon absorption by the N-H comp... Read More about Band-gap profiling by laser writing of hydrogen-containing III-N-Vs.

Eclipsing Binary Stars: the Royal Road to Stellar Astrophysics (2012)
Presentation / Conference Contribution
Taylor. (2011, October). Eclipsing Binary Stars: the Royal Road to Stellar Astrophysics. Presented at Pas De Deux conference 2011, Observatoire de Paris, France

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.

Homogeneous studies of transiting planets (2011)
Presentation / Conference Contribution
Southworth, J. (2011, July). Homogeneous studies of transiting planets. Presented at IAUS 282: From Interacting Binaries to Exoplanets: Essential Modeling Tools, Tatranska Lomnica

The derived physical properties of the known transiting extrasolar planetary systems come from a variety of sources, and are calculated using a range of different methods so are not always directly comparable. I present a catalogue of the physical pr... Read More about Homogeneous studies of transiting planets.

Laser writing of the electronic activity of N- and H-atoms in GaAs (2011)
Journal Article
Martelli, F., Rubini, S., Balakrishnan, N., Patanè, A., Makarovsky, O., Polimeni, A., & Capizzi, M. (2011). Laser writing of the electronic activity of N- and H-atoms in GaAs. Applied Physics Letters, 021105 - 021105. https://doi.org/10.1063/1.3610464

We use a focussed laser beam to control the electronic activity of N- and H-atoms in a dilute nitride Ga(AsN)/GaAs quantum well. Our approach yields submicron resolution in the spatial manipulation of the electronic properties and can provide an alte... Read More about Laser writing of the electronic activity of N- and H-atoms in GaAs.

Theoretical Study of Carbon Clusters in Silicon Carbide Nanowires (2011)
Journal Article
(2011). Theoretical Study of Carbon Clusters in Silicon Carbide Nanowires. Journal of Nanotechnology, 1 - 8. https://doi.org/10.1155/2011/203423

Using first-principles methods we performed a theoretical study of carbon clusters in silicon carbide (SiC) nanowires. We examined small clusters with carbon interstitials and antisites in hydrogen-passivated SiC nanowires growth along the [100] and... Read More about Theoretical Study of Carbon Clusters in Silicon Carbide Nanowires.

Boron and nitrogen impurities in SiC nanoribbons: anab initioinvestigation (2011)
Journal Article
Abreu Da Silva Morbec. (2011). Boron and nitrogen impurities in SiC nanoribbons: anab initioinvestigation. Journal of Physics: Condensed Matter, 205504 - 205504. https://doi.org/10.1088/0953-8984/23/20/205504

Using ab initio calculations based on density-functional theory we have performed a theoretical investigation of substitutional boron and nitrogen impurities in silicon carbide (SiC) nanoribbons. We have considered hydrogen terminated SiC ribbons wit... Read More about Boron and nitrogen impurities in SiC nanoribbons: anab initioinvestigation.

NuGrid: s process in massive stars (2009)
Presentation / Conference Contribution
Hirschi, R., Frischknecht, U., Pignatari, M., Thielemann, F.-K., Bennett, M., Diehl, S., Fryer, C., Herwig, F., Hungerford, A., Magkotsios, G., Rockefeller, G., Timmes, F., & Young, P. (2008, July). NuGrid: s process in massive stars. Poster presented at 10th Symposium on Nuclei in the Cosmos, Mackinac Island, Michigan, USA

The s-process production in massive stars at very low metallicities is expected to be negligible due to the low abundance of the neutron source 22Ne, to primary neutron poisons and decreasing iron seed abundances. However, recent models of massive st... Read More about NuGrid: s process in massive stars.

Exact and approximate relations for the spin-dependence of the exchange energy in high magnetic fields (2009)
Journal Article
(2009). Exact and approximate relations for the spin-dependence of the exchange energy in high magnetic fields. International Journal of Modern Physics B, 3004 - 3008. https://doi.org/10.1142/S0217979209062712

The exchange energy of an arbitrary collinear-spin many-body system in an external magnetic field is a functional of the spin-resolved charge and current densities. Within the framework of density-functional theory (DFT), we show that the dependence... Read More about Exact and approximate relations for the spin-dependence of the exchange energy in high magnetic fields.

Massive Stars as Cosmic Engines through the Ages (2008)
Journal Article
Hirschi, R. (2008). Massive Stars as Cosmic Engines through the Ages. Proceedings of the International Astronomical Union, 3-16. https://doi.org/10.1017/S1743921308020292

Some useful developments in the model physics are briefly presented, followed by model results on chemical enrichments and WR stars. We discuss the expected rotation velocities of WR stars. We emphasize that the (C+O)/He ratio is a better chemical in... Read More about Massive Stars as Cosmic Engines through the Ages.

Contribution of the second Landau level to the exchange energy of the three-dimensional electron gas in a high magnetic field (2008)
Journal Article
(2008). Contribution of the second Landau level to the exchange energy of the three-dimensional electron gas in a high magnetic field. Physical review B: Condensed matter and materials physics, https://doi.org/10.1103/PhysRevB.78.085107

We derive a closed analytical expression for the exchange energy of the three-dimensional interacting electron gas in strong magnetic fields, which goes beyond the quantum limit (L=0) by explicitly including the effect of the second, L=1, Landau lev... Read More about Contribution of the second Landau level to the exchange energy of the three-dimensional electron gas in a high magnetic field.

Spatial Distribution of Nucleosynthesis Products in Cassiopeia A: Comparison Between Observations and 3D Explosion Models (2008)
Presentation / Conference Contribution
(2008, July). Spatial Distribution of Nucleosynthesis Products in Cassiopeia A: Comparison Between Observations and 3D Explosion Models. Presented at 10th Symposium on Nuclei in the Cosmos, Mackinac Island, Michigan, USA

We examine observed heavy element abundances in the Cassiopeia A supernova remnant as a constraint on the nature of the Cas A supernova. We compare bulk abundances from 1D and 3D explosion models and spatial distribution of elements in 3D models with... Read More about Spatial Distribution of Nucleosynthesis Products in Cassiopeia A: Comparison Between Observations and 3D Explosion Models.

Difficulties in Probing Nuclear Physics: A Study of Ti and Ni (2008)
Presentation / Conference Contribution
Hungerford, A., Fryer, C. L., Timmes, F. X., Young, P., Bennett, M., Diehl, S., Herwig, F., Hirschi, R., Pignatari, M., Magkotsios, G., & Rockefeller, G. (2008, July). Difficulties in Probing Nuclear Physics: A Study of Ti and Ni. Paper presented at 10th Symposium on Nuclei in the Cosmos, Mackinac Island, Michigan, USA

The nucleosynthetic yield from a supernova explosion depends upon a variety of effects: progenitor evolution, explosion process, details of the nuclear network, and nuclear rates. Especially in studies of integrated stellar yields, simplifications re... Read More about Difficulties in Probing Nuclear Physics: A Study of Ti and Ni.

44Ti and 56Ni in core-collapse supernovae (2008)
Presentation / Conference Contribution
Magkotsios, G., Timmes, F. X., Wiescher, M., Fryer, C. L., Hungerford, A., Young, P., Bennett, M., Diehl, S., Herwig, F., Hirschi, R., Pignatari, M., & Rockefeller, G. (2008, July). 44Ti and 56Ni in core-collapse supernovae. Paper presented at 10th Symposium on Nuclei in the Cosmos, Mackinac Island, Michigan, USA

We investigate the physical conditions where 44Ti and 56Ni are created in core-collapse supernovae. In this preliminary work we use a series of post-processing network calculations with parametrized expansion profiles that are representative of the w... Read More about 44Ti and 56Ni in core-collapse supernovae.

Developments in physics of massive stars (2007)
Presentation / Conference Contribution
Meynet, G., Ekström, S., Maeder, A., Hirschi, R., Georgy, C., & Beffa, C. Developments in physics of massive stars. Presented at Symposium S250: Massive Stars as Cosmic Engines

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.

The ultra-compact binary candidate KUV 23182+1007 is a bright quasar (2007)
Journal Article
Southworth, J., Schwope, A., Gaensicke, B., & Schreiber, M. (2007). The ultra-compact binary candidate KUV 23182+1007 is a bright quasar. arXiv,

KUV 23182+1007 was identified as a blue object in the Kiso UV Survey in the 1980s. Classification-dispersion spectroscopy showed a featureless continuum except for a strong emission line in the region of He II 4686 A. This is a hallmark of the rare A... Read More about The ultra-compact binary candidate KUV 23182+1007 is a bright quasar.

Very low metallicity massive star models: Pre-SN evolution and primary nitrogen production (2006)
Journal Article
Hirschi, R. (2006). Very low metallicity massive star models: Pre-SN evolution and primary nitrogen production. Astronomy & Astrophysics, 461(2), 571 - 583. https://doi.org/10.1051/0004-6361%3A20065356

Two series of models were computed. The first series consists of 20 solar mass models with varying initial metallicity (Z=0.02 down to Z=10^{-8}) and rotation (V_{ini}=0-600 km/s). The second one consists of models with an initial metallicity of Z=10... Read More about Very low metallicity massive star models: Pre-SN evolution and primary nitrogen production.

Kinematic structure in the young σ Orionis association (2006)
Journal Article
Jeffries, R., Maxted, P., Oliveira, J., & Naylor, T. (2006). Kinematic structure in the young σ Orionis association. Monthly Notices of the Royal Astronomical Society, 371(1), L6 - L10. https://doi.org/10.1111/j.1745-3933.2006.00196.x

We have used precise radial velocity measurements for a large number of candidate low-mass stars and brown dwarfs, to show that the young Sigma Ori ``cluster'' consists of two spatially superimposed components which are kinematically separated by 7 k... Read More about Kinematic structure in the young σ Orionis association.

Eclipsing Binaries in Open Clusters (2006)
Journal Article
Southworth, J., & Viggo Clausen, J. (2006). Eclipsing Binaries in Open Clusters. Astrophysics and Space Science, 304, Article 199–202. https://doi.org/10.1007/s10509-006-9110-3

Detached eclipsing binaries are very useful objects for calibrating theoretical stellar models and checking their predictions. Detached eclipsing binaries in open clusters are particularly important because of the additional constraints on their age... Read More about Eclipsing Binaries in Open Clusters.