UA cloudflare authentication

 

Mass dependent galaxy transformation mechanisms in the complex environment of SuperGroup Abell 1882

dc.contributorKeel, W. C.
dc.contributorButa, Ronald James
dc.contributorYun, Min S.
dc.contributorIrwin, Jimmy A.
dc.contributorToale, Patrick A.
dc.contributorTownsley, Dean M.
dc.contributor.advisorButa, Ronald James
dc.contributor.authorSengupta, Aparajita
dc.contributor.otherUniversity of Alabama Tuscaloosa
dc.date.accessioned2017-03-01T16:54:00Z
dc.date.available2017-03-01T16:54:00Z
dc.date.issued2013
dc.descriptionElectronic Thesis or Dissertationen_US
dc.description.abstractWe present our data and results from panchromatic photometry and optical spectrometry of the nearest (extremely rich) filamentary large scale structure, SuperGroup Abell 1882. It is a precursor of a cluster and is an inevitable part of the narrative in the study of galaxy transformations. There has been strong empirical evidence over the past three decades that galaxy environment affects galaxy properties. Blue disky galaxies transform into red bulge-like galaxies as they traverse into the deeper recesses of a cluster. However, we have little insight into the story of galaxy evolution in the early stages of cluster formation. Besides, in relaxed clusters that have been studied extensively, several evolutionary mechanisms take effect on similar spatial and temporal scales, making it almost impossible to disentangle different local and global mechanisms. A SuperGroup on the other hand, has a shallower dark-matter potential. Here, the accreting galaxies are subjected to evolutionary mechanisms over larger time and spatial scales. This separates processes that are otherwise superimposed in rich cluster-filament interfaces. As has been found from cluster studies, galaxy color and morphology tie very strongly with local galaxy density even in a complex and nascent structure like Abell 1882. Our major results indicate that there is a strong dependence of galaxy transformations on the galaxy masses themselves. Mass- dependent evolutionary mechanisms affect galaxies at different spatial scales. The galaxy color also varies with radial projected distance from the assumed center of the structure for a constant local galaxy density, indicating the underlying large scale structure as a second order evolutionary driver. We have looked for clues to the types of mechanisms that might cause the transformations at various mass regimes. We have found the thoroughly quenched low mass galaxies confined to the groups, whereas there are evidences of intermediate-mass quenched galaxies even in the far outskirts. However, unlike what we observe in this system, ideally would we expect the dwarf galaxies with their shallow potentials to be more vulnerable than more massive galaxies, and hence be quenched earlier. We propose harassment and/or ram-pressure stripping as the mechanism that might lead to the quenched galaxies near or inside the high density, high velocity dispersion region in and near the groups; and mergers as the mechanism for the intermediate mass quenched galaxies at the low density, low velocity dispersion outskirts. We also identify a starburst population preferentially occurring within the filaments, at least a subset of which must be progenitors of the quenched galaxies at the core of Abell 1882. This also indicates a higher degree of preprocessing within the filaments as compared to that of the field.en_US
dc.format.extent137 p.
dc.format.mediumelectronic
dc.format.mimetypeapplication/pdf
dc.identifier.otheru0015_0000001_0001432
dc.identifier.otherSengupta_alatus_0004D_11684
dc.identifier.urihttps://ir.ua.edu/handle/123456789/1896
dc.languageEnglish
dc.language.isoen_US
dc.publisherUniversity of Alabama Libraries
dc.relation.hasversionborn digital
dc.relation.ispartofThe University of Alabama Electronic Theses and Dissertations
dc.relation.ispartofThe University of Alabama Libraries Digital Collections
dc.rightsAll rights reserved by the author unless otherwise indicated.en_US
dc.subjectAstrophysics
dc.titleMass dependent galaxy transformation mechanisms in the complex environment of SuperGroup Abell 1882en_US
dc.typethesis
dc.typetext
etdms.degree.departmentUniversity of Alabama. Department of Physics and Astronomy
etdms.degree.disciplinePhysics
etdms.degree.grantorThe University of Alabama
etdms.degree.leveldoctoral
etdms.degree.namePh.D.

Files

Original bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
file_1.pdf
Size:
7.88 MB
Format:
Adobe Portable Document Format