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dc.contributor.advisorDriver, Simon
dc.contributor.advisorRobotham, Aaron
dc.contributor.authorAlpaslan, Mehmet
dc.coverage.spatialxxv, 165 p.en_US
dc.date.accessioned2014-06-24T09:00:22Z
dc.date.available2014-06-24T09:00:22Z
dc.date.issued2014-06-25
dc.identifieruk.bl.ethos.605817
dc.identifier.urihttps://hdl.handle.net/10023/4906
dc.description.abstractI have investigated the properties of the large scale structure of the nearby Universe using data from the Galaxy and Mass Assembly survey (GAMA). I generated complementary halo mass estimates for all groups in the GAMA Galaxy Group Catalogue (G³C) using a modified caustic mass estimation algorithm. On average, the caustic mass estimates agree with dynamical mass estimates within a factor of 2 in 90% of groups. A volume limited sample of these groups and galaxies are used to generate the large scale structure catalogue. An adapted minimal spanning tree algorithm is used to identify and classify structures, detecting 643 filaments that measure up to 200 Mpc/h, each containing 8 groups on average. A secondary population of smaller coherent structures, dubbed `tendrils,' that link filaments together or penetrate into voids are also detected. On average, tendrils measure around 10 Mpc/h and contain 6 galaxies. The so-called line correlation function is used to prove that tendrils are real structures rather than accidental alignments. A population of isolated void galaxies are also identified. The properties of filaments and tendrils in observed and mock GAMA galaxy catalogues agree well. I go on to show that voids from other surveys that overlap with GAMA regions contain a large number of galaxies, primarily belonging to tendrils. This implies that void sizes are strongly dependent on the number density and sensitivity limits of the galaxies observed by a survey. Finally, I examine the properties of galaxies in different environments, finding that galaxies in filaments tend to be early-type, bright, spheroidal, and red whilst those in voids are typically the opposite: blue, late-type, and more faint. I show that group mass does not correlate with the brightness and morphologies of galaxies and that the primary driver of galaxy evolution is stellar mass.en_US
dc.language.isoenen_US
dc.publisherUniversity of St Andrews
dc.rightsCreative Commons Attribution-NonCommercial-ShareAlike 4.0 International
dc.rights.urihttp://creativecommons.org/licenses/by-nc-sa/4.0/
dc.subjectAstronomyen_US
dc.subjectExtragalactic astronomyen_US
dc.subjectGalaxy surveysen_US
dc.subjectLarge scale structureen_US
dc.subjectGalaxy groupsen_US
dc.subjectGalaxy evolutionen_US
dc.subjectMinimal spanning treesen_US
dc.subject.lccQB991.L37A6
dc.subject.lcshLarge scale structure (Astronomy)en_US
dc.subject.lcshGalaxiesen_US
dc.subject.lcshGalaxies--Evolutionen_US
dc.titleThe cosmic web unravelled : a study of filamentary structure in the Galaxy and Mass Assembly surveyen_US
dc.typeThesisen_US
dc.type.qualificationlevelDoctoralen_US
dc.type.qualificationnamePhD Doctor of Philosophyen_US
dc.publisher.institutionThe University of St Andrewsen_US


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Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International
Except where otherwise noted within the work, this item's licence for re-use is described as Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International