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Publié par | technische_universitat_munchen |
Publié le | 01 janvier 2009 |
Nombre de lectures | 9 |
Langue | English |
Poids de l'ouvrage | 3 Mo |
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TechnischeUniversit¨atMu¨nchen,PhysikDepartment,T30d
MaxPlanckInstitutfu¨rPhysik(WernerHeisenbergInstitut)
Dissertation
Thelong-livedstauasathermalrelic
JosefPradler
Vollsta¨ndigerAbdruckdervonderFakulta¨tfu¨rPhysikderTechnischenUniversita¨t
Mu¨nchenzurErlangungdesakademischenGradeseines
DoktorsderNaturwissenschaften(Dr.rer.nat.)
genehmigtenDissertation.
Vorsitzender:Univ.-Prof.Dr.L.Oberauer
Pru¨ferderDissertation:1.Univ.-Prof.Dr.A.Ibarra
2.Univ.-Prof.Dr.W.F.L.Hollik
DieDissertationwurdeam23.06.2009beiderTechnischenUniversita¨tMu¨ncheneinge-
reichtunddurchdieFakulta¨tfu¨rPhysikam20.07.2009angenommen.
ii
mmauSyr
TheresultspresentedinthisthesishaveinpartalreadybeenpublishedinRefs.[1,2,
3,4,5]listedoverleaf(pagev).WeconsiderphysicsbeyondtheStandardModelwhich
impliestheexistenceaoflong-livedelectromagneticallychargedmassiveparticlespecies
(CHAMP)whichwedenotebyX±.Wediscussindetailtheuniquesensitivitytheearly
Universeexhibitsonthemerepresenceandonthedecayofsuchaparticle.ACHAMP
canberealizedinsupersymmetric(SUSY)extensionsoftheStandardModel.Wecarry
outadetailedstudyofgravitino(Ge)darkmatterscenariosinwhichthelighterscalar
tau(stau,e1)isthelightestStandardModelsuperpartnersothate1=X.Wealso
provideathoroughinvestigationofthethermalfreeze-outprocessofe1.
Thethesisisdividedintothreeparts:
PartI:Inthispartweconsideragenericbutweak-scaleCHAMP.InChapter1we
setthestageforthecominginvestigationsbyshortlyreviewingtheframeworkofBig
BangNucleosynthesis(BBN),byworkingoutthetypicalCHAMPfreeze-outabundance,
andbyreviewingthestringentconstraintsarisingfromsuchadecayingcomponent
during/afterBBN.WealsotakeacriticallookattheBBNconstraintsarisingfrom
thehadronicdecaymodesofanarbitraryexotic.Inparticular,wedeveloponarened
treatmentoftheCoulombstoppingmechanismofchargedhadrons.
InChapter2wediscussthephysicswhichemergeswhenthelightelementsfusedin
BBNarecapturedbyXatthetimeofprimordialnucleosynthesis.Sincetheassociated,
moststrikingeectswereonlydiscoveredrecently,weprovideadetailedexpositionof
thetopic.Inparticular,weexplicitlyshowhowtoobtaintheratesforboundstate
formationwhichcarryanitechargeradiuscorrectionofthenucleus.Intheremainder
ofthischapter,whichisbasedon[4],wefocusonthecatalyticproductionof6Liand
9Be.There,wealsodiscusstheissueofapotentiallate-timecatalysisduetoproton-
CHAMPboundstates.UponsolutionofthefullsetofBoltzmannequationsweobtain
stringentconstraintsontheprimordialpresenceoflong-livedXfromoverproduction
of6Li.Moreover,settinganupperlimitontheabundanceofprimordial9Beallowsus
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vi
toconstrainthisscenarioalsofromcatalytic9Beproduction.
PartII:ThesecondpartisdevotedtoscenariosinwhichGeisthelightestsupersym-
metricparticle(LSP)ande1isthenext-to-lightestSUSYparticle(NLSP).InChapter3
wefocusonthegravitinoLSPasadarkmattercandidate.Werecollecttheresultson
thermalgravitinoproduction,considerexplicitlythepost-inationaryreheatingprocess,
andobtainanupdateontheupperboundonthereheatingtemperatureoftheUniverse
fromthermalproduction.
InChapter4wethenfocusongravitinodarkmatterscenariosinwhiche1isthe
NLSP.Thischapterresemblesmanyoftheresultsoftheresearchpapers[1,2,3,4].We
constrainthegravitino-stauscenariobyincorporatingtheBBNboundsfrome1-decays
previouslyobtainedintheliterature.Inaddition,theconcreterealizationofthelong-
livedCHAMPscenarioallowsustoemployourresultsonthecatalyticproductionof
9Beand6Li.IntheframeworkoftheconstrainedminimalsupersymmetricStandard
Model(CMSSM)ae1NLSPcanbenaturallyaccommodated.There,weshowthatthe
novelcatalyticeectsseverelyconstrainthereheatingtemperatureoftheUniverseand
potentiallyimplyveryheavysuperparticlemassspectrawhichwillbehardtoprobeat
theupcomingLargeHadronCollider(LHC)experiments.Wealsoconsiderexplicitly
thepossibilityofanon-standardcosmologicalevolutionandcheckfortheviabilityof
thermalleptogenesis.
PartIII:Chapter5constitutesthenalpartofthisthesisandisbasedon[5].There,
wetakeanin-depthlookintothechemicaldecouplingprocessofthelong-livede1from
theprimordialplasma.Thequantityofinterestisthethermalfreeze-outabundanceof
thestau.WeidentifyitsdependenceonthecrucialSUSYparametersandalsoshow
thatitsensitivelydependsonthedetailsoftheHiggssector.Stauannihilationintonal
stateHiggsesaswellasresonantannihilationviatheheavyCPevenHiggsbosoncan
substantiallydepletethedecouplingyield.Remarkably,wendthesefeaturesarealready
realizedintheCMSSM.Inthoseregionsoftheparameterspaceeventhemostrestrictive
boundsfromthethermalcatalysisofBBNreactionscanpotentiallyberespected.We
discusstheimplicationsforthegravitino-stauscenario.
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Theresultsobtainedinthisthesishaveinpartalreadybeenpublishedinthefollowing
references:
[1]ConstraintsontheReheatingTemperaturein
GravitinoDarkMatterScenarios
J.PradlerandF.D.Steen
Phys.Lett.B648,224(2007)[arXiv:hep-ph/0612291]
[2]ImplicationsofCatalyzedBBNintheCMSSMwith
GravitinoDarkMatter
J.PradlerandF.D.Steen
Phys.Lett.B666,181(2008)[arXiv:0710.2213]
[3]CBBNintheCMSSM
J.PradlerandF.D.Steen
Eur.Phys.J.C56,287(2008)[arXiv:0710.4548]
[4]ConstraintsonSupersymmetricModelsfromCatalytic
PrimordialNucleosynthesisofBeryllium
M.Pospelov,J.Pradler,andF.D.Steen
JCAP0811,020(2008)[arXiv:0807.4287]
[5]ThermalRelicAbundancesofLong-LivedStaus
J.PradlerandF.D.Steen
Nucl.Phys.B809,318(2009)[arXiv:0808.2462]
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Acknowledgements
IwouldrstliketoexpressmygratitudetowardsmyresearchadvisorFrankDaniel
SteenattheMaxPlanckInstituteforPhysics(MPI)forhiscontinuoussupport,col-
laboration,andforthemanyinterestingdiscussionswehad.Ifurtherthankhimforthe
coordinationoftheInternationalMaxPlanckResearchSchoolfromwhereIalsohave
receivedmyfunding.IamthankfultotheMPIforprovidinganoptimalplacetowork,
inparticular,tothesecretaryRositaJurgeleitforherfriendlyhelpandtoThomasHahn
forhiscomputersupport.
IwouldliketothankAlejandroIbarraforbeingmyocialadvisorattheTechnical
UniversityMunichandthusforprovidingtheacademicframeworktomyPhDstudies.
Forhissupport,advice,andforholdingtogethertheenjoyableatmosphereintheMPI
“AstroparticleGroup”IamgratefultoGeorgRaelt.
ManyinsightsoftherstpartIowetoMaximPospelovwhomIalsowouldliketothank
forhisinvitationtotheUniversityofVictoria.IamgratefultoGarySteigmanforhis
friendlyexplanationsduringhisvisitinMunich.SimonEidelman,TilmanPlehnand
StefanHofmannIwantthankfortheirgeneraladvice.
ManythankstothefriendswhichIhadthechancetomeetattheMPI,inparticular,
toSteveBlanchet,KoushikDutta,FlorianHahn-Woernle,MaxHuber,andFelixRust.
FortheirfriendshipIamalsomostgratefultoUlrichMattandErikHo¨rtnagl.
Iamdeeplyindebtedtomyfamily,foremosttomyparents,fortheirunconditional
loveandsupportandtoIrinaBavykinaforallherunderstanding,encouragement,and
patienceoverthelastthreeyears.
TothememoryofFlorianKunz.
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Contents
Summary
Acknowledgements
IBBNwithalong-livedCHAMP
iii
iiv
1
1BBNandparticledecays3
1.1PrimordialnucleosynthesisafterWMAP...................3
1.2BBNasaprobeforNewPhysics.......................4
1.3TypicalCHAMPabundances.........................7
1.4ParticledecaysduringBBN..........................11
1.5AcriticallookathadronicconstraintsforT.100keV...........14
1.5.1Energytransferinbinarycollisions..................15
1.5.2Hadron-electronscattering.......................17
1.5.3Cutoconsiderationsforchargedparticles..............19
1.5.4DiscussiononCoulombstopping...................22
1.ALorentztransformations............................25
2BoundstatesandcatalysisofBBN27
2.1Basicboundstateproperties.........................27
2.2Wavefunctionsoftherelativemotion....................29
2.2.1Discretespectrum...........................30
2.2.2Continuousspectrum..........................34
ix
xContents
2.3Formationofboundstates...........................37
2.3.1Photo-dissociationandrecombinationcrosssection.........39
2.4Nuclearreactionswithboundstatesandtheircatalysis...........41
2.4.1Catalysisof6Liproduction......................43
2.4.2Catalysisof9Beproduction......................46
2.5Chargeexchangereactionsandlatetimecatalysis.............49
2.5.1Relaxationafterchargeexchange...................55
2.6ConstraintsontheXlifetimeandabundance...............57
IIThegravitino-stauscenario
16
3Gravitinosasaprobefortheearliestepochs63
3.1Thegravitino-stauscenario..........................63
3.2Supergravityandbasicpropertiesofthegravitino..............64
3.3Thermalgravitinoproductionandreheating.................65
3.3.1Reheatingphase............................69
3.4ConstraintsonT...............................71
R
4ThestauastheNLSP75
4.1Genericconstraintsonthegravitino-stauscenario..............75
4.2Thegravitino-stauscenariointheCMSSM.................82
4.2.1Lowerlimitonm..........................83
2/14.2.2UpperboundonT..........................86
R4.2.3ExemplaryparameterscansintheCMSSM.............87
4.2.4Late-timeentropyproduction.....................93
4.2.5Viabilityofthermalleptogenesis...................97
IIIThelong-livedstauasathermalrelic
5Thermalrelicstauabundances
101
103
Contentsxi
5.1Staumixingandmasseigenstates.......................105
5.2Calculationofthethermalrelicstauabundance...............106
5.3Dependenceofst