I propose to prospective Diploma students, Master students, or short-stay interns various research projects related to brown dwarfs. The Max Planck Institute for Astronomy also invites students to conduct Miniforschung projects. The working conditions at the MPIA are excellent, and offers a stimulating look into world-class research.

New cool brown dwarfs will reveal the chemistry and dynamics of ultra-cool atmospheres, similar to those of exoplanets. They are our best laboratory to study the atmospheres of those objects which are always much fainter than their parent star, and hard to observe. Building a better brown dwarf statistics will also allow to determine the brown dwarf mass function and Solar neighbourhood population (proposal).

You will reduce imaging data using existing (and tested) pipelines, and interpret the results. At least three months.

When a nearby star or brown dwarf passes close to the line of sight of a distant star (within a few arcsecondes) it produces a shift in the position of the background star of a few dozen to hundred of microarcsecondes, in reach of upcoming interferometers such as VLTI's PRIMA or LINC-NIRVANA on the LBT, that will gives a direct (model-independent) mass measurement. Using existing high-quality position and proper motion catalogues, you'll search for targets for these new machines: objects that we expect will produce a microlensing signal, that we will later monitor to measure their mass.

You will search in large databases using (partly existing) scripts, and select the most interesting targets. At least 3 months in total.

Mass function and formation history: It is not possible to directly reconstruct the mass function of brown dwarfs based on their luminosity function, because of the age-mass degenacy of the (cooling) brown dwarfs. Instead, we have to perform a simulation of the Solar neighbourhood brown dwarf population using existing cooling (structure), spectroscopic (atmospheric) models and a star formation history. The simulation wil then be compared to existing and forthcoming brown dwarf samples-a crucial contribution to a long-term research (proposal).

You will write the simulation and if time allows compare it to existing data sets. At least 4 months. Requires some computing (programming) knowledge.