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Abstract:
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The studyofgalaxiesthroughhighredshiftsarekeytounderstandingthe
evolutionofgalaxiesthroughcosmictimes.Assuchobjectsareverydifficultto
observedirectly,theyaremainlyexaminedusingempiricallyderivedtoolssuchas
the numerouscorrelationsbetweentheirdifferentparametriccharacteristics,one
of thembeingthelinearrelationshipbetweenfar-infraredandradioemissionin
star-forming galaxies,namedtheFarInfrared-Radio(FIR)Correlation.Although
the correlationwasconsideredtobestableintermsoflinearity,recentworks,
whichincludegalaxiesathighredshifts(0 < z< 6), showedalargedeviation
from thecorrelationinthesesystems.Thegoalofthisdoctoraldissertationis
an examinationofthephysicalprocessesthatleadtothiskindofbehavior.As
a possiblecauseofthisevolution,wewillassumeforthefirsttime,andexamine
interactionsbetweengalaxies(collisionsandcloseapproaches).Interactionsbe-
tweengalaxiesleadtotheformationofshockwavesonlargescalesthatcanlead
to changesintherelationshipbetweeninfraredandradioemissions.Ourhypoth-
esis wastestedinseveralstadiumsandthemainresultsareasfollows:1.We
developedmodelsoftheevolutionoftheFIRcorrelationwithredshiftasfunctions
of thegalaxyinteractionrate.Wetestedthemodelsonasampleofgalaxieswith
an alreadydeterminedmorphologyseparatelyfordiscgalaxiesandforgalaxies
that haverecentlybeenorarecurrentlyinteracting-irregulargalaxies.
2. Inasmallsampleof34galaxiesthatwetookfrompaperMiettinenetal.(2017),
it wasshownthatthereisanindicationthattheinteractionbetweengalaxiescan
beresponsiblefortheevolutionofthecorrelationwiththeredshift.
3. Thenextanalysiswasperformedonamuchlargersampleofstar-forming
galaxies takenfromCOSMOSfield,wherewedidnotfindanyevolutionofcorre-
lation withtheredshift.Also,itwasshownthatthemeanvalueofthecorrelation
parameter islowerinirregulargalaxiesthanindiskgalaxies.
Although recentobservationsindicatedanevolutionoftheFIRcorrelation
with redshift,theresultsofthisresearchfailedtoreproducethatevolutionand
showedthattheFIRcorrelationisstablewithredshift.However,itwasalso
shownthatduetotheinteractionofgalaxies,theevolutionoftheFIRcorrelation
is possibleiftherepresentationofinteractingsystemsinthesampleishigher. |