About

Markus Rabus, Assistant Professor at the Universidad Católica de la Santísima Concepción in the Departamento de Matemática y Física Aplicadas.

My research

I am interested in understanding the physics of low-mass objects, from cool dwarf stars to planets, with a strong focus on time-domain wide-field projects. In addition to my research interests in astrophysics, I am interested in data-intensive astronomy.

Rubin Observatory

Currently, I am assessing the performance of the LSST pipeline in crowded fields, therefore I analyze DECam images with the Rubin pipeline. During the early commissioning phase, I will participate in the assement of the photometric and astrometric quality of the Rubin data. My aim is to understand the different noise components and correlations present in the data set, like e.g., systematic noise in the time series. I am interested in evaluating the astrometric errors and understanding their limitations with respect to high proper motion objects and detection. I am leading the In-Kind Contributions to Rubin Observatory System Integration, Test, and Commissioning Efforts: “Observing support and science validation of time series photometry” and I am Co-I for commissioining effort “Science validation for astrometry”

Exoplanets and Browns dwarfs

Exoplanets can be detected in different ways. My primary research focuses on the transit and the microlensing method. Both will initially detect a planet candidate photometrically. In a transiting planet system, the exoplanet will leave a signature in the light curves as it crosses our view of the host star. Stellar microlensing events will show anomalies in the presence of a planet. In 2010, I joined the MiNDSTEp project (Microlensing Network for the Detection of Small Terrestrial Exoplanets). Using the Danish 1.5m telescope at La Silla and the Lucky Cam imager, the we are tracking microlensing events in real time. Brown dwarfs are interesting because they can show variabilities in their flux due to weather patterns. Changes in their astrometric position can indicate an undetected companion.

Very-low mass stars

The estimation of parameters and properties of an exoplanet are connected to the stellar host. Understanding the stellar physics and inferring precise stellar parameters is therefore essential. These late-type stars pose a challenge as their physical parameters cannot be modeled very well, i.e., models under-predict the stellar radius and over-predict the effective temperature.