Aug 16, 2014

Searching for Old Novae IIIa


We are interested in the long-term behavior of erupting systems known as classical novae. They are often closely monitored during their eruptions and then mostly ignored after the eruption is over. We are using SALT to observe old novae and measure their current brightness, so we can see how it has changed over the years and decades, and compare it to theoretical models. In this proposal, we take advantage of SALT’s large size, which gives us the ability to look at very faint objects and measure their current brightness level.

Stellar and wind parameters of OB donor stars in HMXBS: spectroscopic survey with SALT


High mass X-ray binaries containing a supergiant OB donar star as some of the most active and exciting X-ray binares in existance.The donar stars large wind is accreted by the compact companion releasing large amounts of X-ray. Through a spectra study of these stars we can estimate the wind parameters and hence further understand the accretion process.

Aug 14, 2014

High resolution spectroscopy of V1369 Cen


In December 2013, a bright nova appeared in the southern hemisphere. For a whole month in December this object was visible with the naked eye near the southern cross. We aim to use SALT and its high resolution spectrograph to study the properties of the ejected material following this nova outburst.

Aug 12, 2014

The radial velocity survey for circumbinary planets around eclipsing binary stars


The program aims at searching for circumbinary exoplanets, so such planets beyond our Solar System which orbit two stars instead of one.

HRS observations of rapidly oscillating (roAp) stars


Waves inside some stars make their light to change periodically. These changes are called pulsations. By breaking down this variable light into colours, thereby forming a spectrum of a star we can learn many important aspects of a star. Our project studies the spectra of stars with surface temperature of between 6000 and 10000 degrees in order to study how the different elements of these stars are distributed in different layers of the surface layers of the star. This will ultimately allow us to learn in detail what role the magnetic field in these stars affect their structures.

Aug 11, 2014

Rapid oscillations in spectroscopically selected chemically peculiar stars


In this program we study chemically peculiar Ap stars which show overabundances of chemical elements like chromium and strontium. These stars also have very large overabundances of rare earth elements including praseodimium, neodimium, europium. Ap stars rotate more slow then normal stars with the same spectral type.These stars also have strong magnetic fields and some of them show pulsations with very short period.

A Precision Test of Low Mass Stellar Evolution Models


Jul 31, 2014

Why does it flare? The eccentric, heavyweight neutron star in IGR J17544-2619


I am studying a binary star, in which one of the massive companions has exploded, leaving behind a “neutron star”. This neutron star orbits the surviving companion every five days. Theory says that this orbit must be circular, but X-ray observations suggest that it should be eccentric (flattened). The aim of these observations is to figure out the real shape of the orbit.

Jul 30, 2014

Ionized Gas Kinematics for Obscured Quasars with Molecular Gas Measurements


We are studying the gas a galaxy that contains a powerful, “hidden” supermassive black hole at its center. The radiation from this black hole lights up the gas in the galaxy, much like a fluorescent lamp, and we are using SALT to study this fluorescent light. The light we observe with SALT will tell us about how the gas is rotating and moving around inside the galaxy, and help us determine what effects the black hole’s radiation might have on how the galaxy grows and forms stars over the history of the Universe.

Jul 28, 2014

Longevity of Dark Matter Substructures in Abell 3827


Our Universe matter content today is dominated by Dark Matter.If it is called dark matter, it is because we don’t know much about its nature.Abell 3827 is an exceptional massive galaxy cluster not too far from us. Its core is formed by four massive galaxies, that are still in the process of merging together.This configuration is really rare and makes Abell 3827 a primary target to study the evolution of dark matter.With these observations, we will be able to see where the stars (luminous matter) and the dark matter are situated with a really high accuracy.This is mandatory to understand the history of this rare and exceptional galaxy cluster, but not only ! By looking at the location of the stars compared to the dark matter, we will be able to derive clues on the properties of dark matter particles.