Investigating substructures in stellar and gas kinematics of nearby galaxies

Supervisor: Dr. Sabine Thater

Co-supervisor: Jonelle Walsh (A&m University)

Contact information: sabine.thater@univie.ac.at 

Expected duration: 9 months

Project description & Goals:

Resolved stellar and gas kinematics of galaxies combined with dynamical models can provide important constraints on galaxy components that are not observable on their own, like the central black hole and dark matter. In this project, the student will analyse detailed optical and near-infrared stellar and gas kinematics maps after extracting them from integral-field spectroscopic observations. Stellar and gas kinematic maps sometimes have misaligned axes with the photometric axes  (e.g., https://arxiv.org/abs/1802.00014 ) which can give indications of the previous formation history of the galaxies. In this work, we will investigate the fraction of kinematic misalignment in a sample of 20 galaxies (of different mass ranges) and then analyse the kinematic maps with a python-version of  Kinemetry (https://arxiv.org/pdf/astro-ph/0512200.pdf ) to investigate underlying substructures in those maps like spirals or inflow to the central massive black hole in those galaxies. The data set is unique as we cover both the central regions of the galaxies with high resolution as well as larger scales of the galaxies. The student will be part of a large international collaboration, results of this work are planned to be published and later used in order to build dynamical models and measure central black hole masses.

 

 

Working plan & Milestones (including final thesis):

  1. Research the importance of stellar and gas kinematics on nearby galaxies. Get to know the galaxy sample, the observations and the method.
  2. Extract the stellar and gas kinematics from the optical and near-infrared integral field spectroscopic observations with pPXF (data reduction might be involved in a later stage, but is optional)
  3. Qualitative analysis of the extracted kinematics
  4. Quantitative analysis using Kinemetry and search for kinematic substructures
  5. Interpretation of the results with respect to galaxy evolution and write up thesis

Requirements / special skills: Interest in integral field spectroscopy, stellar kinematics. Some python (or equivalent IDL, C, R) coding and statistics would be helpful.

References:

https://arxiv.org/abs/1802.00014

https://arxiv.org/pdf/astro-ph/0512200.pdf