Observations

Mar 18, 2019

Spectroscopic investigations of Cepheids and stars belonging to Galactic open clusters and associations

2018-2-MLT-004

Spectroscopic investigations of Cepheids and stars belonging to Galactic open clusters and associations

Reverberation mapping of low luminosity active galactic nuclei

2018-1-SCI-037

Probing the inner structure of AGN through reverberation mapping technique.

HRS HS-mode commissioning

2018-2-COM-001

Getting the HRS tuned up for exoplanet science

Mar 17, 2019

Asymmetry is Destiny: Wolf-Rayet Binary Stars as GRB Progenitors

2018-2-MLT-005

This program aims to use the recently-commissioned high-precision spectropolarimetry mode of RSS to probe the prodigious mass-loss from certain massive evolved stars known as Wolf-Rayet stars which are in binary systems. These objects are possible progenitors of Gamma-Ray Bursts, which are the most energetic explosions yet known, and can be seen across the entire known universe.

Spectroscopic investigations of Cepheids and stars belonging to Galactic open clusters and associations

2018-2-MLT-004

Spectroscopic investigations of Cepheids and stars belonging to Galactic open clusters and associations

SALT Spectroscopy of Gaia Hypervelocity Stars

2018-2-SCI-027

Following fast-moving stars found by Gaia. @_sublunar_ @kenjshen

HRS HS-mode commissioning

2018-2-COM-001

Getting the HRS tuned up for exoplanet science

Mar 16, 2019

Follow-up of interesting binaries and high-order multiple systems uncovered with the Gaia-ESO Survey

2018-1-MLT-009

Stellar multiplicity is ubiquitous in galaxies because stars are born in clusters or associations rather than in an isolated way. Around 50% of stars similar to the Sun have companions and this fraction increases for high mass stars. Multiple stellar systems, when detected by the radial velocity method using spectrographs, are called spectroscopic binaries.This program is dedicated to the follow-up of the most interesting spectroscopic binaries discovered within the Gaia-ESO Survey. It will provide a better insight on stellar multiplicity (and the way stars form in groups) as well as on stellar evolution and interaction between closeby companions.

HRS spectroscopy to unveil the parameters of giants in yellow symbiotic systems

2018-2-SCI-021

We propose to obtain high resolution (R~40000) high S/N (~>50) spectra for 20 of so called yellow symbiotic systems using HRS spectrograph in MR mode. The aim of the proposal is to use the red arm HRS spectra to measure abundances of chemical elements using the spectral synthesis. We will employ the method of standard LTE analysis with use of a hydrostatic model atmospheres. We will also look for possible abundance anomalies due to, e.g., former mass transfer pollution. We will use new information about orbital parameters and Gaia DR2 distances to revise and put new constraints on the physical parameters (temperature, luminosity, abundances) of these giants. It seems be very likely that these objects may turn out to have significantly larger diameters, and so be located at longer distances, be significantly colder and more luminous – the bright giants rather than a normal giants.

Symbiotic stars – important tracers of late evolutionary stages III

2018-1-MLT-005

We propose a large spectroscopic monitoring of a sample of Magellanic symbiotic stars composed of cold red giant stars and hot white dwarfs, which challenge the binary star evolution models because they do not predict their existence. Our proposed observations will allow us to measure the masses of the two stars in the binary system. They will also help us to understand the formation and evolution of these theoretically impossible although existing binaries.