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Nucleosynthesis Calculations from Core-Collapse Supernovae (2008)
Presentation / Conference Contribution
(2008, July). Nucleosynthesis Calculations from Core-Collapse Supernovae. Presented at 10th Symposium on Nuclei in the Cosmos, Mackinac Island, Michigan, USA

We review some of the uncertainties in calculating nucleosynthetic yields, focusing on the explosion mechanism. Current yield calculations tend to either use a piston, energy injection, or enhancement of neutrino opacities to drive an explosion. We s... Read More about Nucleosynthesis Calculations from Core-Collapse Supernovae.

Complete nucleosynthesis calculations for low-mass stars from NuGrid (2008)
Presentation / Conference Contribution
(2008, July). Complete nucleosynthesis calculations for low-mass stars from NuGrid. Presented at 10th Symposium on Nuclei in the Cosmos, Mackinac Island, Michigan, USA

Many nucleosynthesis and mixing processes of low-mass stars as they evolve from the Main Sequence to the thermal-pulse Asymptotic Giant Branch phase (TP-AGB) are well understood (although of course important physics components, e.g. rotation, magneti... Read More about Complete nucleosynthesis calculations for low-mass stars from NuGrid.

Pushing the precision limit of ground-based eclipse photometry (2008)
Book Chapter
(2008). Pushing the precision limit of ground-based eclipse photometry. In Transiting Planets (IAU S253)

Until recently, it was considered by many that ground-based photometry could not reach the high cadence sub-mmag regime because of the presence of the atmosphere. Indeed, high frequency atmospheric noises (mainly scintillation) limit the precision th... Read More about Pushing the precision limit of ground-based eclipse photometry.

A survey for low mass spectroscopic binary stars in the young clusters around sigma Orionis and lambda Orionis (2008)
Journal Article
(2008). A survey for low mass spectroscopic binary stars in the young clusters around sigma Orionis and lambda Orionis. Monthly Notices of the Royal Astronomical Society, 2210-2224. https://doi.org/10.1111/j.1365-2966.2008.13008.x

We have obtained multi-epoch, high-resolution spectroscopy of 218 candidate low-mass stars and brown dwarfs in the young clusters around sigma Ori and lambda Ori. We find that 196 targets are cluster members based on their radial velocity, the equiva... Read More about A survey for low mass spectroscopic binary stars in the young clusters around sigma Orionis and lambda Orionis.

Disc-Magnetosphere interactions in Cataclysmic Variable Stars (2007)
Journal Article
(2007). Disc-Magnetosphere interactions in Cataclysmic Variable Stars. Proceedings of the International Astronomical Union, https://doi.org/10.1017/S1743921307009684

I review, from an observational perspective, the interactions of accretion discs with magnetic fields in cataclysmic variable stars. I start with systems where the accretion flows via a stream, and discuss the circumstances in which the stream forms... Read More about Disc-Magnetosphere interactions in Cataclysmic Variable Stars.

A new AMS facility in Caserta/Italy (2007)
Journal Article
(2007). A new AMS facility in Caserta/Italy. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 14 -17. https://doi.org/10.1016/j.nimb.2007.01.139

A new AMS system has been installed at Center for Isotopic Research on Cultural and Environmental Heritage (CIRCE) in Caserta/Italy. It was built by National Electrostatics Corp. Middleton, WI/USA, and arrived at CIRCE in the middle of January 2005;... Read More about A new AMS facility in Caserta/Italy.

Testing convection in stellar models using detached eclipsing binaries (2006)
Presentation / Conference
(2006, August). Testing convection in stellar models using detached eclipsing binaries. Presented at IAUS 239 (Convection in Astrophysics), Prague

The fundamental properties of detached eclipsing binary stars can be measured very accurately, which could make them important objects for constraining the treatment of convection in theoretical stellar models. However, only four or five pieces of in... Read More about Testing convection in stellar models using detached eclipsing binaries.

The lithium depletion boundary in NGC 2547 as a test of pre-main-sequence evolutionary models (2005)
Journal Article
Jeffries, R. D., & Oliveira, J. M. (2005). The lithium depletion boundary in NGC 2547 as a test of pre-main-sequence evolutionary models. Monthly Notices of the Royal Astronomical Society, 358(1), 13 -29. https://doi.org/10.1111/j.1365-2966.2005.08820.x

Intermediate resolution spectroscopy from the ESO Very Large Telescope is analysed for 63 photometrically selected low-mass (0.08-0.30 Msun) candidates of the open cluster NGC 2547. We have confirmed membership for most of these stars using radial ve... Read More about The lithium depletion boundary in NGC 2547 as a test of pre-main-sequence evolutionary models.

Yields of rotating stars at solar metallicity (2004)
Journal Article
Hirschi, R., Meynet, G., & Maeder, A. Yields of rotating stars at solar metallicity. https://doi.org/10.1051/0004-6361%3A20041554. Manuscript submitted for publication

We present a new set of stellar yields obtained from rotating stellar models at solar metallicity covering the massive star range (12-60 solar masses). The stellar models were calculated with the latest version of the Geneva stellar evolution code de... Read More about Yields of rotating stars at solar metallicity.

Some updates on the role of magnetic fields in cataclysmic variables (2004)
Journal Article
Hellier, C. (2004). Some updates on the role of magnetic fields in cataclysmic variables

In this review talk I cover some recent developments in understanding the role that magnetic fields play in cataclysmic variables. I discuss the recent DNO--QPO unification models; the disk--magnetosphere boundary; some issues concerning the soft bla... Read More about Some updates on the role of magnetic fields in cataclysmic variables.

An L'-band survey for circumstellar discs around low-mass stars in the young σ Orionis cluster (2004)
Journal Article
Jeffries, R., Oliveira, J., & Van Loon, J. (2004). An L'-band survey for circumstellar discs around low-mass stars in the young σ Orionis cluster. Monthly Notices of the Royal Astronomical Society, 347(4), 1327 -1336. https://doi.org/10.1111/j.1365-2966.2004.07315.x

We present new K- and L'-band imaging of a representative sample of members of the young 3-5 Myr old sigma Orionis cluster. We identified objects with (K-L') excess by analysing colour-colour diagrams and comparing the observations with empirical mai... Read More about An L'-band survey for circumstellar discs around low-mass stars in the young σ Orionis cluster.

Cool stars in NGC 2547 and pre-main-sequence lithium depletion (2003)
Journal Article
Jeffries, R., Oliveira, J., Barrado y Navascués, D., & Stauffer, J. (2003). Cool stars in NGC 2547 and pre-main-sequence lithium depletion. Monthly Notices of the Royal Astronomical Society, 343(4), 1271-1284. https://doi.org/10.1046/j.1365-8711.2003.06768.x

We present the results of a spectroscopic survey of X-ray selected, low-mass candidate members of the young open cluster NGC 2547. Using a combination of photometry, spectroscopic indices and radial velocities we refine our candidate list and then us... Read More about Cool stars in NGC 2547 and pre-main-sequence lithium depletion.

X-ray spectroscopy and variability of the luminous quasar PDS 456
Thesis
Matzeu, G. X-ray spectroscopy and variability of the luminous quasar PDS 456. https://keele-repository.worktribe.com/output/409748

In this thesis I present contemporary X-ray observations of the “Rosetta Stone” of black hole winds, the luminous quasar PDS 456. I perform a detailed analysis of a recent, long Suzaku campaign in 2013 (of ~ 1 Ms duration) where the X-ray flux was un... Read More about X-ray spectroscopy and variability of the luminous quasar PDS 456.

Electron-induced secondary electron emission spectroscopy of surfaces
Thesis
Harris, P. Electron-induced secondary electron emission spectroscopy of surfaces. https://keele-repository.worktribe.com/output/412914

An introduction to the subject of secondary electron emission, characteristic energy loss and Auger electron spectroscopy is given, together with a brief survey of some relevant published work. An apparatus consisting of a 3600 retarding field spectr... Read More about Electron-induced secondary electron emission spectroscopy of surfaces.

Time-resolved studies of the crystallisation and dehydration of lactose and other hydrates using synchrotron x-ray and neutron powder diffraction techniques
Thesis
Swann, N. J. Time-resolved studies of the crystallisation and dehydration of lactose and other hydrates using synchrotron x-ray and neutron powder diffraction techniques. https://keele-repository.worktribe.com/output/409716

In-situ time-resolved synchrotro11 x-ray and neutron powder diffraction tC'c:hniques have bc(-'n applied to the study of solid stat<' structural t.ransi tions within the organic. polymorphic molecular systems of lactose. trehalose and t heophylline....

Evolution of electron capture supernova progenitors: new models, improved nuclear physics and hydrodynamic mixing uncertainties
Thesis
Evolution of electron capture supernova progenitors: new models, improved nuclear physics and hydrodynamic mixing uncertainties. https://keele-repository.worktribe.com/output/405119

Electron capture supernovae (EC-SNe) are the deaths of approximately 8-10M stars. In this thesis, the evolution of 8-12M stars is calculated using the MESA stellar evolution code. The aims of this thesis are to produce the most advanced and up-to-dat... Read More about Evolution of electron capture supernova progenitors: new models, improved nuclear physics and hydrodynamic mixing uncertainties.