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[{"key": "dc.contributor.author", "value": "Snellman, Tomas", "language": null, "element": "contributor", "qualifier": "author", "schema": "dc"}, {"key": "dc.date.accessioned", "value": "2014-01-30T10:03:32Z", "language": "", "element": "date", "qualifier": "accessioned", "schema": "dc"}, {"key": "dc.date.available", "value": "2014-01-30T10:03:32Z", "language": "", "element": "date", "qualifier": "available", "schema": "dc"}, {"key": "dc.date.issued", "value": "2013", "language": null, "element": "date", "qualifier": "issued", "schema": "dc"}, {"key": "dc.identifier.other", "value": "oai:jykdok.linneanet.fi:1307415", "language": null, "element": "identifier", "qualifier": "other", "schema": "dc"}, {"key": "dc.identifier.uri", "value": "https://jyx.jyu.fi/handle/123456789/42892", "language": "", "element": "identifier", "qualifier": "uri", "schema": "dc"}, {"key": "dc.description.abstract", "value": "Yksi raskasionit\u00f6rm\u00e4yksen ominaisuuksista on syntyv\u00e4n matalaenergisen hiukkasvirran ep\u00e4isotrooppisuus. T\u00e4m\u00e4 ep\u00e4isotrooppisuus karakterisoidaan useimmiten Fourierin sarjakehitelm\u00e4n ja sen kertoimien avulla. \r\n\r\nT\u00e4ss\u00e4 ty\u00f6ss\u00e4 tutkin kahta puolta hiukkasvirrassa. Ensimm\u00e4inen on tunnistettujen hiukkasten virta ja niin sanottu kvarkkilukuskaalaus. RHIC-kiihdyttimell\u00e4 on huomattu, ett\u00e4 skaalaamalla hadronien ja mesonien havaitut isotrooppisuuskertoimet kvarkkiluvuilla erot eri hiukkasten v\u00e4lill\u00e4 h\u00e4vi\u00e4v\u00e4t l\u00e4hes kokonaan. T\u00e4m\u00e4n tulkittiin tarkoittavan sit\u00e4, ett\u00e4 hiukkasvirran kehitykseen vaikuttaa l\u00e4hinn\u00e4 t\u00f6rm\u00e4yksen partoninen vaihe ja hadronisaation j\u00e4lkeisell\u00e4 vaiheella ei ole vaikutusta.\r\n\r\nToinen puoli tutkimuksessani on hiukkasvirran muuttuminen t\u00f6rm\u00e4yksest\u00e4 toiseen ja havaittujen Fourier-kertoimien jakauma. Kokeelliset menetelm\u00e4t kuitenkin v\u00e4\u00e4rist\u00e4v\u00e4t jakaumia. V\u00e4\u00e4ristymien poistamiseen k\u00e4yt\u00e4n bayesilaista menetelm\u00e4\u00e4, jota kokeilin ensin yksinkertaisella Monte Carlo -simulaatiolla. \r\n\r\nT\u00e4m\u00e4n ty\u00f6n olen suorittanut tutkimalla AMPT-mallilla tuotettua LHC-energiaa vastaavaa t\u00f6rm\u00e4ysdataa keskeisyydelt\u00e4\u00e4n erilaisissa t\u00f6rm\u00e4yksiss\u00e4. AMPT on hybridimalli, joka k\u00e4ytt\u00e4\u00e4 Monte Carlo -menetelm\u00e4\u00e4 raskasionit\u00f6rm\u00e4yksen simulointiin. Havaitsin, ett\u00e4 AMPT-malli LHC-energialla ei noudata kvarkkilukuskaalausta. Esit\u00e4n my\u00f6s tulokset Fourier-kertoimien jakaumista. Monte Carlo -testin perusteella uskon, ett\u00e4 toisen asteen kertoimien jakauma vastaa todellista jakaumaa koko tutkitussa datassa. Kolmannen asteen kertoimien kohdalla bayesilainen menetelm\u00e4 sen sijaan toimii ainoastaan keskeisimmiss\u00e4 t\u00f6rm\u00e4yksiss\u00e4, joissa signaali on vahvin.", "language": "fi", "element": "description", "qualifier": "abstract", "schema": "dc"}, {"key": "dc.description.abstract", "value": "In this thesis I study two aspects related to anisotropic flow coefficients v2 and v3 in heavy-ion collisions. The study is done for Pb-Pb collisions at \u221asNN = 2.76 TeV using data simulated by A MultiPhase Transport (AMPT) model. First I study flow of identified charged particles, pions, kaons and protons. At RHIC in Au-Au collisions at \u221asNN = 200 GeV it has been observed that scaling v2 of identified hadrons with the number of quarks and plotting it as a function of transverse kinetic energy KET produces almost perfect scaling between different particle species. This was taken as an indication that flow is mainly generated in the partonic phase and is not strongly affected by the hadronic phase. However, in Pb-Pb col- lisions at \u221asNN = 2.76 TeV in LHC the scaling has been observed to break down. AMPT model uses a simple quark coalescence model, which was used to explain the scaling at RHIC energies. Because of the scaling breakdown at LHC the coalescence model has been challenged in the field. In my studies I have observed that AMPT does not produce perfect quark number scaling, even though it would be expected because of the coalescence model.\r\nAnother aspect studied here is event-by-event flow. Event-by-event flow is connected to the fluctuations in the initial collisions. Only recently the field has started to study fluctuations and event-by-event flow. I will show distributions of event-by-event flow coefficients in the AMPT model. In addition to the true fluctuations the distributions have a significant smearing component from limited resolution resulting from finite multiplicity in a single event. I will use a data-driven unfolding method based on an iterative Bayesian procedure to remove the smearing effects. I will test the procedure in a toy Monte Carlo simulation to test its performance and apply it to AMPT data. I have observed that based on the Monte Carlo the procedure works for v2 in general and for v3 in central collisions.", "language": "en", "element": "description", "qualifier": "abstract", "schema": "dc"}, {"key": "dc.description.provenance", "value": "Submitted using Plone Publishing form by Tomas Snellman (towisnel) on 2014-01-30 10:03:31.060559. Form: Pro gradu -lomake (1 tekij\u00e4) (https://kirjasto.jyu.fi/julkaisut/julkaisulomakkeet/pro-gradu-lomake-1-tekijae). JyX data:", "language": "en", "element": "description", "qualifier": "provenance", "schema": "dc"}, {"key": "dc.description.provenance", "value": "Submitted by jyx lomake-julkaisija (jyx-julkaisija@noreply.fi) on 2014-01-30T10:03:32Z\r\nNo. of bitstreams: 2\r\nURN:NBN:fi:jyu-201401301166.pdf: 7942301 bytes, checksum: b648bc4d55943d600689fd8e72d48009 (MD5)\r\nlicense.html: 4928 bytes, checksum: 4cd13f5b5c1d9bd26452bade19a2ec33 (MD5)", "language": "en", "element": "description", "qualifier": "provenance", "schema": "dc"}, {"key": "dc.description.provenance", "value": "Made available in DSpace on 2014-01-30T10:03:32Z (GMT). No. of bitstreams: 2\r\nURN:NBN:fi:jyu-201401301166.pdf: 7942301 bytes, checksum: b648bc4d55943d600689fd8e72d48009 (MD5)\r\nlicense.html: 4928 bytes, checksum: 4cd13f5b5c1d9bd26452bade19a2ec33 (MD5)\r\n Previous issue date: 2013", "language": "en", "element": "description", "qualifier": "provenance", "schema": "dc"}, {"key": "dc.format.extent", "value": "1 verkkoaineisto (71 sivua)", "language": null, "element": "format", "qualifier": "extent", "schema": "dc"}, {"key": "dc.format.mimetype", "value": "application/pdf", "language": null, "element": "format", "qualifier": "mimetype", "schema": "dc"}, {"key": "dc.language.iso", "value": "eng", "language": null, "element": "language", "qualifier": "iso", "schema": "dc"}, {"key": "dc.rights", "value": "In Copyright", "language": "en", "element": "rights", "qualifier": null, "schema": "dc"}, {"key": "dc.subject.other", "value": "raskasioni", "language": null, "element": "subject", "qualifier": "other", "schema": "dc"}, {"key": "dc.title", "value": "Identified charged particle flow and unfolding event-by-event flow in heavy ion collisions", "language": null, "element": "title", "qualifier": null, "schema": "dc"}, {"key": "dc.type", "value": "master thesis", "language": null, "element": "type", "qualifier": null, "schema": "dc"}, {"key": "dc.identifier.urn", "value": "URN:NBN:fi:jyu-201401301166", "language": null, "element": "identifier", "qualifier": "urn", "schema": "dc"}, {"key": "dc.type.dcmitype", "value": "Text", "language": "en", "element": "type", "qualifier": "dcmitype", "schema": "dc"}, {"key": "dc.type.ontasot", "value": "Pro gradu -tutkielma", "language": "fi", "element": "type", "qualifier": "ontasot", "schema": "dc"}, {"key": "dc.type.ontasot", "value": "Master\u2019s thesis", "language": "en", "element": "type", "qualifier": "ontasot", "schema": "dc"}, {"key": "dc.contributor.faculty", "value": "Matemaattis-luonnontieteellinen tiedekunta", "language": "fi", "element": "contributor", "qualifier": "faculty", "schema": "dc"}, {"key": "dc.contributor.faculty", "value": "Faculty of Sciences", "language": "en", "element": "contributor", "qualifier": "faculty", "schema": "dc"}, {"key": "dc.contributor.department", "value": "Fysiikan laitos", "language": "fi", "element": "contributor", "qualifier": "department", "schema": "dc"}, {"key": "dc.contributor.department", "value": "Department of Physics", "language": "en", "element": "contributor", "qualifier": "department", "schema": "dc"}, {"key": "dc.contributor.organization", "value": "University of Jyv\u00e4skyl\u00e4", "language": "en", "element": "contributor", "qualifier": "organization", "schema": "dc"}, {"key": "dc.contributor.organization", "value": "Jyv\u00e4skyl\u00e4n yliopisto", "language": "fi", "element": "contributor", "qualifier": "organization", "schema": "dc"}, {"key": "dc.subject.discipline", "value": "Teoreettinen fysiikka", "language": "fi", "element": "subject", "qualifier": "discipline", "schema": "dc"}, {"key": "dc.subject.discipline", "value": "Theoretical Physics", "language": "en", "element": "subject", "qualifier": "discipline", "schema": "dc"}, {"key": "dc.date.updated", "value": "2014-01-30T10:03:33Z", "language": "", "element": "date", "qualifier": "updated", "schema": "dc"}, {"key": "dc.type.coar", "value": "http://purl.org/coar/resource_type/c_bdcc", "language": null, "element": "type", "qualifier": "coar", "schema": "dc"}, {"key": "dc.rights.accesslevel", "value": "openAccess", "language": "fi", "element": "rights", "qualifier": "accesslevel", "schema": "dc"}, {"key": "dc.type.publication", "value": "masterThesis", "language": null, "element": "type", "qualifier": "publication", "schema": "dc"}, {"key": "dc.subject.oppiainekoodi", "value": "4024", "language": null, "element": "subject", "qualifier": "oppiainekoodi", "schema": "dc"}, {"key": "dc.subject.yso", "value": "fysiikka", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "hiukkaset", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "ionit", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.format.content", "value": "fulltext", "language": null, "element": "format", "qualifier": "content", "schema": "dc"}, {"key": "dc.rights.url", "value": "https://rightsstatements.org/page/InC/1.0/", "language": null, "element": "rights", "qualifier": "url", "schema": "dc"}, {"key": "dc.type.okm", "value": "G2", "language": null, "element": "type", "qualifier": "okm", "schema": "dc"}]
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