Directly to content
  1. Publishing |
  2. Search |
  3. Browse |
  4. Recent items rss |
  5. Open Access |
  6. Jur. Issues |
  7. DeutschClear Cookie - decide language by browser settings

Stucture of the obscured Galactic disk with pulsating variables

Hajdu, Gergely

[img] PDF, English - main document
Download (10MB) | Lizenz: Creative Commons LizenzvertragStucture of the obscured Galactic disk with pulsating variables by Hajdu, Gergely underlies the terms of Creative Commons Attribution 4.0

Citation of documents: Please do not cite the URL that is displayed in your browser location input, instead use the DOI, URN or the persistent URL below, as we can guarantee their long-time accessibility.

Abstract

Bright pulsating variables, such as Cepheids and RR Lyrae, are prime probes of the structure of both the young and old stellar components of the Milky Way. However, the far side of the Galactic disk has not yet been mapped using such variables as tracers, due to the severe extinction caused by foreground interstellar dust. In this thesis, the near-infrared light curves from the VISTA Variables in the Vía Láctea survey are utilized to penetrate these regions of high extinction and thus discover thousands of previously “hidden” Cepheid and RR Lyrae variables. The analysis of the light curves of RR Lyrae variables, was performed with a newly developed fitting algorithm, and their metallicities determined from their near-infrared light-curve shapes, using a newly developed method. These photometric metal abundances, combined with their positions within the Galactic disk, lend support to theories of an early, inside-out formation of the Galactic disk. The newly discovered Cepheids were classified into the old (Type II) and young (Classical) subtypes. A new near-infrared extinction law was determined using the Type II Cepheids, taking advantage of their concentration around the Galactic center. The distribution of the Classical Cepheids in the Galactic disk follows both the Galactic warp and the flare of the Galactic disk at large Galactocentric radii. A first attempt has been made to connect the current locations of the Classical Cepheids to the spiral arm structure of the Milky Way.

Item Type: Dissertation
Supervisor: Catelan, Prof. Dr. Márcio
Place of Publication: Heidelberg; Santiago de Chile
Date of thesis defense: 6 August 2019
Date Deposited: 15 Nov 2019 09:14
Date: 2019
Faculties / Institutes: The Faculty of Physics and Astronomy > Dekanat der Fakultät für Physik und Astronomie
Subjects: 520 Astronomy and allied sciences
Controlled Keywords: Fotometrie, Stellarastronomie, Milchstraßensystem
Uncontrolled Keywords: RR Lyrae Cepheid Variable stars Verändliche Sterne
About | FAQ | Contact | Imprint |
OA-LogoDINI certificate 2013Logo der Open-Archives-Initiative