The environmental conditions in the center of the Milky Way galaxy (Central Molecular Zone; CMZ) are much more extreme than in the disk of the galaxy with molecular gas properties similar to those seen in galaxies at z~2. While the CMZ hosts several massive star clusters, the formation of stars from these dense molecular clouds and the feedback of these massive stars on the ISM is not well understood. I present in my thesis a case study of a few regions in the CMZ using VLA continuum and spectral line observations. I explore feedback eects of recent star formation (a young massive stellar cluster) on the surrounding ISM (molecular and ionized gas). Using the kinematic information of molecular and ionized gas, obtained dierent species of spectral lines, I will determine the line of sight geometry of the dierent gas components. I will then establish the relationship of these components to the larger structure of molecular gas in the CMZ.
Kinematics and evolution of massive star formation in the central molecular zone of the galactic center
Abstract
Details
- Title: Subtitle
- Kinematics and evolution of massive star formation in the central molecular zone of the galactic center
- Creators
- Natalie Butterfield - University of Iowa
- Contributors
- Cornelia Lang (Advisor)Robert Mutel (Committee Member)Steven Spangler (Committee Member)Kenneth Gayley (Committee Member)Farhad Yusef-Zadeh (Committee Member)
- Resource Type
- Dissertation
- Degree Awarded
- Doctor of Philosophy (PhD), University of Iowa
- Degree in
- Physics
- Date degree season
- Summer 2018
- DOI
- 10.17077/etd.id5w0xp4
- Publisher
- University of Iowa
- Number of pages
- xvi, 124 pages
- Copyright
- Copyright © 2018 Natalie Butterfield
- Comment
This thesis has been optimized for improved web viewing. If you require the original version, contact the University Archives at the University of Iowa: https://www.lib.uiowa.edu/sc/contact/.
- Language
- English
- Description illustrations
- illustrations (some color)
- Description bibliographic
- Includes bibliographical references (pages 120-124).
- Public Abstract (ETD)
The center of our galaxy (Central Molecular Zone; CMZ) harbors unusual physical properties that are not normally seen in the local universe. These unusual properties are typically only found in other galaxy centers and in early universe galaxies. The close proximity to the CMZ, at only ~25,000 light years away, allows astronomers to image individual gas clouds containing these unusual physical properties and investigate their characteristics.
Within the past decade new sensitive telescopes have conducted surveys of the CMZ. These surveys show an apparent connection between individual clouds and a large-scale gas structure. Astronomers have attempted to fit individual gas clouds to a possible larger gas structure (`streams'). However, several locations in the CMZ show multiple cloud components indicating that there may be multiple clouds along a single line-of-sight. Due to this complexity, modeling these clouds is difficult and assumptions in the 3D location of individual clouds can influence the model as a whole.
My thesis focuses on a few CMZ locations that contain multiple cloud components. I target these regions with higher resolution data to determine the cause of the complex velocity structure (i.e., kinematics). Using the data presented in this thesis, I disentangle the complex kinematics to construct a simple solution (e.g., an expanding shell) for the targeted region. I then compare the kinematics of the clouds to the modeled streams to determine how they relate to the larger gas structure. The results in my thesis provide a localized consistency check for several complex kinematic regions and presents additional detailed information that can be used in future orbital models.
- Academic Unit
- Physics and Astronomy
- Record Identifier
- 9983776877802771