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[{"key": "dc.contributor.advisor", "value": "Suhonen, Jouni", "language": "", "element": "contributor", "qualifier": "advisor", "schema": "dc"}, {"key": "dc.contributor.author", "value": "Hellgren, Matti", "language": "", "element": "contributor", "qualifier": "author", "schema": "dc"}, {"key": "dc.date.accessioned", "value": "2020-08-31T06:01:05Z", "language": null, "element": "date", "qualifier": "accessioned", "schema": "dc"}, {"key": "dc.date.available", "value": "2020-08-31T06:01:05Z", "language": null, "element": "date", "qualifier": "available", "schema": "dc"}, {"key": "dc.date.issued", "value": "2020", "language": "", "element": "date", "qualifier": "issued", "schema": "dc"}, {"key": "dc.identifier.uri", "value": "https://jyx.jyu.fi/handle/123456789/71547", "language": null, "element": "identifier", "qualifier": "uri", "schema": "dc"}, {"key": "dc.description.abstract", "value": "Tutkielmassa tarkasteltiin astrofysikaalisten neutriinojen sirontaa stabiileista jodi- ja\ncaesium ytimist\u00e4 127I and 133Cs, tarkoituksena arvioida kyseisten ytimien hy\u00f6dynt\u00e4misen\nmahdollisuutta neutriinojen havaitsemisessa. Ty\u00f6ss\u00e4 k\u00e4sitelt\u00e4v\u00e4t reaktiot\nkoostuivat elastisista ja ep\u00e4elastisista heikon neutraalin virran neutriino-ydin ja\nantineutriino-ydin sironnoista. Reaktioihin osallistuvina neutriinoina k\u00e4ytettiin\nsupernovar\u00e4j\u00e4hdyksiss\u00e4 alkunsa saaneita elektronin neutriinoja. Semileptonisten\nneutriino-ydin prosessien teoreettinen formalismi k\u00e4ytiin yksityiskohtaisesti l\u00e4pi, ja\nkeskeisimm\u00e4t yht\u00e4l\u00f6t johdettiin tarkasti. Ty\u00f6n kannalta oleellisin suure oli sironnan\nvaikutusala.\nTy\u00f6ss\u00e4 tarkasteltujen parittoman massaluvun ytimien mallintamisessa k\u00e4ytetty\nmalli oli MQPM, joka itsess\u00e4\u00e4n rakentuu BCS-mallin ja QRPA:n p\u00e4\u00e4lle. MQPM:n\nsoveltaminen parittoman massaluvun ytimien mallintamiseen tapahtui siten tekem\u00e4ll\u00e4\nensiksi BCS- ja QRPA-laskut parittomien ytimien vieress\u00e4 oleville parillis-parillisille\nreferenssiytimille (126Te, 128Xe, 132Xe and 134Ba), ja k\u00e4ytt\u00e4m\u00e4ll\u00e4 n\u00e4ist\u00e4 saatuja tuloksia\nhaluttujen MQPM-laskujen tekemiseen. Valitusta ydinmallista saatiin ytimien\ntilojen aaltofunktiot ja n\u00e4it\u00e4 vastaavat energiat, sek\u00e4 redusoidut neutraalin virran\nyhden kappaleen siirtym\u00e4tiheydet, joita k\u00e4ytettiin vaikutusalojen laskemisessa. Ty\u00f6n\nlopullisina tuloksina olivat energiakeskiarvoistetut kokonaisvaikutusalat, jotka saatiin\nintegroimalla kaksoisdifferentiaalinen vaikutusala kulmakoordinaattien yli, summaamalla\nytimen kaikkien mahdollisten lopputilojen yli, ja integroimalla lopuksi saatu\nvaikutusala ja neutriinojen energiaspektri energian yli. Neutriinojen energiaspektrille\nk\u00e4ytettiin muunnettua termist\u00e4 kahden parametrin Fermi-Dirac jakaumaa.\nTuloksina saatujen QRPA-spektrien yhteensopivuus vastaavien kokeellisten spektrien\nkanssa oli kohtalainen, kun taas MQPM-spektreiss\u00e4 oli muutamia poikkeavuuksia,\nerityisesti spektrien matalaenergiap\u00e4\u00e4ss\u00e4. N\u00e4ill\u00e4 oli minimaalinen vaikutus vaikutusaloihin,\njoiden tulokset olivat verrattavissa aiempien vastaavanlaisten tutkimuksien\ntulosten kanssa. Kaiken kaikkiaan saatuihin tuloksiin voidaan suhtautua varovaisen\noptimistisesti, vaikka ne ovatkin tutkimuskysymyksen kannalta prelimin\u00e4\u00e4risi\u00e4.\nMik\u00e4\u00e4n tuloksissa ei suoranaisesti viitannut siihen, ett\u00e4 tutkittuja ytimi\u00e4 ei voitaisi\nk\u00e4ytt\u00e4\u00e4 neutriinojen havaitsemisessa, mutta aiheeseen liityville jatkotutkimuksille on\ntarvetta, jotta kysymykseen voidaan vastata tyhjent\u00e4v\u00e4sti.", "language": "fi", "element": "description", "qualifier": "abstract", "schema": "dc"}, {"key": "dc.description.abstract", "value": "The scattering of astrophysical neutrinos off the stable Iodine and Caesium nuclei\n127I and 133Cs was studied to explore the possibility of utilizing them in neutrino\ndetection. The reactions considered in this work were elastic and inelastic weak\nneutral current neutrino-nucleus and antineutrino-nucleus scatterings. The neutrinos\nthat were included were of the e-flavour and had their origin in supernova core\ncollapse events. The theoretical formalism of semileptonic neutrino-nucleus processes\nwas reviewed in great detail, and several key equations were derived meticulously.\nThe primary quantity of interest was the scattering cross section.\nThe model used for the description of the two odd-A nuclei of interest was the\nMQPM, which is built upon the BCS model and QRPA. MQPM was thus applied to\nthe odd-A nuclei by first performing the BCS and QRPA calculations on even-even\nreference nuclei (126Te, 128Xe, 132Xe and 134Ba) adjacent to the odd-A nuclei, and\nthen using these results to run the MQPM calculations for the odd-A nuclei. The\nnuclear model provided the eigenfunctions and -energies of the nuclei and the reduced\nneutral current one-body transition densities which entered into the cross section\ncalculations. The ultimate results of this thesis were the energy averaged total cross\nsections, which were obtained by integrating the double differential cross section over\nthe angular coordinates, summing over all possible final nuclear states and folding\nthe cross section with the neutrino energy spectrum. The neutrino energy spectrum\nused was a modified two-parameter thermal Fermi-Dirac distribution.\nThe resulting theoretical QRPA spectra were in decent agreement with experimental\nresults, while the MQPM spectra had some discrepancies, particularly at the\nlow-energy end. These had minimal effect on the cross sections, which were found\nto be in line with earlier similar calculations. Overall, the results were cautiously\noptimistic, but preliminary. Nothing in them outright implied that the nuclei considered\nwould not be fit for neutrino detection, but further studies are needed for an\nexhaustive assessment of their suitability for such a role.", "language": "en", "element": "description", "qualifier": "abstract", "schema": "dc"}, {"key": "dc.description.provenance", "value": "Submitted by Paivi Vuorio (paelvuor@jyu.fi) on 2020-08-31T06:01:05Z\nNo. of bitstreams: 0", "language": "en", "element": "description", "qualifier": "provenance", "schema": "dc"}, {"key": "dc.description.provenance", "value": "Made available in DSpace on 2020-08-31T06:01:05Z (GMT). No. of bitstreams: 0\n Previous issue date: 2020", "language": "en", "element": "description", "qualifier": "provenance", "schema": "dc"}, {"key": "dc.format.extent", "value": "128", "language": "", "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": "MQPM", "language": "", "element": "subject", "qualifier": "other", "schema": "dc"}, {"key": "dc.subject.other", "value": "QRPA", "language": "", "element": "subject", "qualifier": "other", "schema": "dc"}, {"key": "dc.subject.other", "value": "BCS", "language": "", "element": "subject", "qualifier": "other", "schema": "dc"}, {"key": "dc.subject.other", "value": "caesium", "language": "", "element": "subject", "qualifier": "other", "schema": "dc"}, {"key": "dc.title", "value": "Neutral current supernova neutrino-nucleus scattering off 127I and 133Cs", "language": "", "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-202008315677", "language": "", "element": "identifier", "qualifier": "urn", "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": "Jyv\u00e4skyl\u00e4n yliopisto", "language": "fi", "element": "contributor", "qualifier": "organization", "schema": "dc"}, {"key": "dc.contributor.organization", "value": "University of Jyv\u00e4skyl\u00e4", "language": "en", "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": "yvv.contractresearch.funding", "value": "0", "language": "", "element": "contractresearch", "qualifier": "funding", "schema": "yvv"}, {"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": null, "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": "", "element": "subject", "qualifier": "oppiainekoodi", "schema": "dc"}, {"key": "dc.subject.yso", "value": "sironta", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "jodi", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "ydinfysiikka", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "hiukkasfysiikka", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "neutriinot", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "supernovat", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "scattering (physics)", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "iodine", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "nuclear physics", "language": null, "element": "subject", "qualifier": "yso", 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