Oct 18, 2017
Spectroscopic monitoring binaries in young moving groups to get dynamical masses for determining their ages
This monitoring program aims to measure the ages of the youngest stars in the universe closest to us. By weighing them and comparing their mass and brightness to models, we can infer just how old (or young) they are. Using the SALT High resolution Spectrograph, we are able to probe these young stars and measure there compositions, thereby estimating the formation mechanisms occurring for these objects. With this knowledge we able then able to fits models to the data and make assumptions on how planets are formed.
Spectroscopic Observations of the Hill Sphere Transit in star Beta Pictoris
South Africa is a growing community of astronomers working on one of many subsets of astronomy like searching for exoplanets. South Africa has premier observing facilities and is an advantaged astronomical observing site due to its incredible dark skies, geographical location, and range of facilities. It provides a unique window on the southern skies covering the gap between observatories in Australia and South America to provide 24 hour coverage of astronomical objects. In addition, access to the Southern African Large Telescope High Resolution Spectrograph (SALT-HRS) in Sutherland provide access explore the Universe and solar systems similar to us. For this project, the ability to coverage this observing window as well as access to the spectroscopic capabilities with SALT will allow a detailed study of any disk that will be detected in the Beta Pictoris system. Exoplanets and the discovery of worlds around other stars are exciting. Discovering a ring system, such as Saturn, around another star is not only an opportunity to discover how our solar system formed, but a chance to help explain how our Universe works. Furthermore, with the opportunity of observing a bright object, schools and amateur astronomers can be engaged to provide additional monitoring of the objects. This will increase the impact of the overall project and provide ways to engage the public in this exciting project and inspire the next generation of scientist.
Preparing for LADUMA: SALT Redshift Measurements
“Laduma” (literally, “it thunders” in the Zulu language) is the unique exclamation used by South Africans to celebrate a goal scored in football (soccer). We have chosen LADUMA as our survey’s name to highlight the unique investment South Africa is making in the construction and operation of MeerKAT as well as our ambitious goal of detecting neutral hydrogen in emission out to redshifts > 1. SALT will be making spectroscopic observations to assist this goal by measuring the distance for hundreds of star forming galaxies
Systematic radial velocity monitoring of likely intermediate period post-AGB binaries
We are searching for binary stars in some of the most beautiful stellar remnants in the Galaxy.
Spectroscopic characterisation of faint Kepler 2 White Dwarfs
White Dwarfs are the end state for 97% of stars including the Sun. Observations of White Dwarfs by NASA’s exoplanet mission, Kepler, show many are unexpectedly variable on timescales of hours and days. What causes this variability? Our project is to characterise White Dwarfs observed by Kepler. One suggestion is that these stars are being polluted by rocky material from asteroids in old planetary systems. Discovery of planets and/or evidence of rocky debris around White Dwarfs will provide the first clues as to the evolution of planetary systems (including our own) at the end stages of a stars’ life.
Oct 17, 2017
Probing open questions about active galactic nuclei with spectropolarimetry
The accretion of material onto supermassive black holes in the centers of galaxies creates a unique, extreme, and complex environment. Because these active galactic nuclei (AGN) may have important impacts on the evolution of galaxies, as well as inform our understanding of how black holes grow and evolve, disentengling their structure (which is not resolved in images) is critical. We plan to use observations of polarized, scattered light from these sources to answer fundamental questions about several observational classes of AGN, including those with powerful outflows and those that may have recently “turned off”.
Nature of galaxies associated with strong MgII absorbers
This program is for identifying high-z galaxies responsible for Mg II absorption seen in the spectra of distant QSOs.
Unveiling powerful “hidden” black holes: redshifts and characteristics of WISE-selected obscured quasars
We are searching for powerful, supermassive black holes in galaxies that are hidden behind dense obscuring clouds of gas and dust and so have been mysterious and difficult find in the past. New infrared observations with the Wide-Field Infrared Survey Explorer (WISE) satellite have allowed us to observe the “heat” from dust heated up by the radiation coming from these powerful black holes, and so identify many thousands of possible hidden supermassive black holes. Observations with SALT will allow us to confirm that these are really black holes, by looking for telltale fluorescent light produced by the black hole lighting up the gas in the their galaxy, and will tell us how far away in the Universe these objects are.
HRS study of long-period eclipsing binaries: towards the true mass-luminosity relation
Study of long-period eclipsing binaries
Oct 15, 2017
Counting symbiotic stars in nearby galaxies
Search for new symbiotic stars in nearby galaxies.