Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 16 of 16 for “"galactic structure"”.
-
Galactic Structure with Giant Stars
… Miras, as chronometers to study the evolution of Galactic structure over stellar age. I study red giants in the Magellanic Clouds, assign them photometric metallicities and map large scale trends both in their chemistry and proper motions. In Chapter 1 I provide an overview of the historical …
-
Fast galactic structure finding using graphics processing units
… used by astronomers to investigate large scale structure formation and galaxy evolution. Structure finding, that is, the discovery of gravitationally-bound objects such as dark matter halos, is a crucial step in many such simulations. During recent years, advancing computational capacity has …
-
An Analysis of Galactic Structure in the Direction of Aquila
Made available in DSpace on 2014-12-05T21:49:58Z (GMT). No. of bitstreams: 1 0002213.pdf: 2175686 bytes, checksum: ed2d7bede6f9ed1c08572cb78f0b9df9 (MD5) Previous issue date: 1950
-
An astrophysical investigation of four classical cepheid variable stars
… law and apply it to problems of galactic structure and extragalactic distances. The intrinsic brightness of these stars together with the fact that they can be observed in external galaxies has made them exceedingly useful in this way.
-
An astrophysical investigation of four classical cepheid variable stars
… law and apply it to problems of galactic structure and extragalactic distances. The intrinsic brightness of these stars together with the fact that they can be observed in external galaxies has made them exceedingly useful in this way.
-
The red clump stars as a distance indicator : review and application
… was primarily to determine the distance to the Galactic Centre using a new technique pioneered by Paczynski and Stanek (1998) that uses the red clump stars as a standard candle. This was made possible by the large number of stars simultaneously observed by the OGLE microlensing project which …
-
A new model of spiral galaxies based on propagating star formation.
… in the literature of either star formation or galactic structure, but the former concentrate on small-scale details, whilst the latter, if they include star formation at all, adopt a very simple approach, for example by assuming a power law relationship between the rate of star formation and …
-
The Universality of Intrinsic Flattening in Extragalactic Stellar Disks
… to constrain the intrinsic flattening, 𝑐/𝑎, of galactic disks. We use “dust-free” 3.6 𝜇m maps of 141 edge-on spiral galaxies from the Spitzer Survey of Stellar Structure in Galaxies (S4G) and its early-type galaxy extension to determine the intrinsic flattening of stellar disks. The proper …
-
Search and characterization of pulsars in southern globular clusters: new methodologies and results from an S-band survey
… and probes of the interstellar medium and Galactic structure. Globular clusters are particularly rich environments for pulsar studies. These dense stellar systems promote frequent dynamical interactions, leading to the formation of exotic systems such as millisecond pulsars in binaries. …
-
Iras oxygen- and carbon-rich miras close to the galactic plane
… to be Mira Variables and that lie close to the galactic plane: -7.0 3 < b < + 1° and 282.°5 < l < 285.°5. Over 1090 JHKL photometry modules were obtained for the sources. From the photometry the sample was shown to comprise 85 Miras, 12 of which had published periods. New periods were determined …
-
The THESAN Project: ionizing escape fractions of reionization-era galaxies
… by galaxies successfully escapes into the intergalactic medium. However, due to the scarcity of high-redshift observational data, the sources driving reionization remain uncertain. In this work we calculate the ionizing escape fractions (𝑓 subscript esc) of reionization-era galaxies from the …
-
A self contamination model for the formation of globular star clusters
… distribution can be used as probes of the early galactic structure. In particular, this model requires an increase in the typical globular cluster mass as one moves out from the galactic center; the masses of the halo clusters are examined, and they show considerable evidence for such a gradient. …
-
A self-contamination model for the formation of globular star clusters
… distribution can be used as probes of the early galactic structure. In particular, this model requires an increase in the typical globular cluster mass as one moves out from the galactic center; the masses of the halo clusters are examined, and they show considerable evidence for such a gradient. …
-
THE CEPHEIDS OF M33: DISTANCE AND METALLICITY EFFECTS THROUGH SLOAN FILTERS
… indicators on both interstellar and intergalactic scales, enabling accurate distance estimates and studies into galactic structure. Cepheids are found in many different environments and are therefore imparted with varying levels of metallicity. The difference in Cepheid metallicities may …
-
Models of the Galaxy and the massive spectroscopic stellar survey RAVE
… of galaxy formation and observational Galactic Astronomy are two fields of research that study the same objects from different perspectives. Simulations try to understand galaxies like our Milky Way from an evolutionary point of view while observers try to disentangle the current …
-
Chemical composition study of Galactic stellar substructures /
… groups stars and to compare the results with Galactic thin- and thick-disc dwarfs. The main atmospheric parameters and abundances of 21 chemical elements have been determined. The abundance pattern of programe stars has similar characteristics to those of the Galactic thick disc, which might …