TheCosmologicalandSolarLithiumProblemsAndtheneedformodelsofnon-standardtransportmechanismsinsidestars
JorgeMeléndez Dep.Astronomia,Univ.SãoPaulo
ThenucleiofthelightelementsweresyntheGzedinthefirstminutesaIertheBigBangFinalabundancesdependonbaryondensityη10
credits: NASA
CosmicMicrowaveBackground
A(Li)=2.67dex (Li/H=4.6510-10)PredictedprimordialLiabundance:
Cyburtetal.2016
Planck(previouslyWMAP)
Baryondensityη10=6.10±0.04 (Planck2015)
Spite&Spite(1982)
RelicLiobservedinmetal-poorstars([Fe/H]<-1)
Wavelength
RelaGveFlux
Asplundetal.(2006)
Stars(Li=2.0–2.25)
Aokietal.(2009)
2.7
Lithiuminstars:Triangles:Asplundetal2006Squares:Bonifacioetal.2007FilledCircles:Aokietal.2009
CMB+BBN
CosmologicalLiproblemPlanck+BBN(Li=2.67)
Discrepancyofabout0.5dex(factorof3)!
SoluGon:newphysics/cosmology?-Fengetal.(2003):superweaklyinterac:ngmassivepar:cledarkma>ersignalsfromtheearlyUniverse-Jedamziketal.(2004):Didsomethingdecay,evaporate,orannihilateduringbigbangnucleosynthesis?-Cocetal.(2007):Coupledvaria:onsoffundamentalcouplingsandprimordialnucleosynthesis-Erkenetal.(2012):AxionDarkMa>erandCosmologicalParameters-Mosquera&Civitarese(2014):SterileneutrinosandBigBangNucleosynthesisinthe3+1scheme-Satoetal.(2017)Asolu:ontoLiproblembylong-livedstau
NewphysicscouldsolvetheLiproblemAsplundetal.(2006)paperhas~350citaGons
StellarsoluGon:Atomicdiffusion?
FromourmodelswithdiffusionwederivethattheaverageLiabundancealongtheSpiteplateauisaboutafactorof2lowerthantheprimordialone.Asaconsequence,thederivedprimordialLiabundancewouldbeconsistentwithahighHeandlowdeuteriumBBN;thisimpliesahighcosmologicalbaryondensityasinferredfromtheanalysesofthecosmicmicrowavebackground.
PreWMAP!
StellarsoluGon:Atomicdiffusion+grad+turbRichardetal.(2005)computedstellarmodelsincludingdiffusion+radiaGveacceleraGon+turbulence
Atleast0.2dexreducGoninstellar7Li
Fuetal.2015
StellarsoluGon:Atomicdiffusion+grad+overshooGng+PMStreatment
?Fuetal.2015
Fieldstarsshowthatmoremodelsareneeded
Meléndezetal.(2010),updated
ComparisonoffieldhalostarswithmodelsbyRichardetal.(2005)
Meléndezetal.(2010),updated
LidepleGoninstarsseemsmetallicitydependent
-2.5 < [Fe/H] < -2.0
-3.0 < [Fe/H] < -2.5
Moremodelsareneeded!Meléndezetal.,inprep.
ApJ2012
NGC6397[Fe/H]=-2.1
SignaturesofatomicdiffusionintheglobularclusterNGC6397
Nordlanderetal.2012
Thesolarlithiumproblem
• ThesolarLiisabout160Gmeslowerthaninmeteorites.
• Liburnsat2.5106K;belowtheconvectionzone:nodepletioninthephotosphere!
www.kgs.ku.edu/
ESO
Solartwins:StarsliketheSunwithin100KineffecGvetemperature,andwithin0.1dexinluminosityand[Fe/H]àmassastheSunàsimilarstellarevoluGon
IshardtostudylithiumRe
laGveFlux Al
Fe
Fe
AlFe
Fe
Fe FeFe
Li
FeFeFe
Fe
Ca
Si
Si
Fe
Fe
Fe
Wavelength(Å)
R=110000S/N=500-1000
Sun
HIP102152
Lithiumdecreasesforoldersolartwins
Carlos,Nissen&Melendez(2016)
Moststarsfollowalithium–agecorrelaGon,includingstarswithplanets
16CygB(planethost)isnormalinLi.Perhaps16CygAaccretedaplanet
Whichisthe“correct”model?
Asweaddmoredataandimprovetheages,itseemsthatnoneofthemodelsreproducethesolartwins
Carlos,Meléndez,Spinaetal.,inprep.
GCEworsensagreement?
GalacGcarchaeologyusingsolartwinsfromHARPS
Bedell,Bean,Meléndezetal.,submived
ArethesetrendsonlyduetodifferentenrichmentchannelsofsupernovaIa&II?OralsodifferenGalatomicdiffusion?
AretheabundanceraGosrelevantforbuildingexoplanetsindependentofage?
Bedell,Bean,Meléndezetal.,submived
Solartwins(bluepoints)suggesthighchemicalhomogeneityinC/O&Mg/Si.
HowaretheraGosaffectedbyatomicdiffusion?
C/O
Mg/Si
Howspecialisourplanetarysystem?
Smallpart(597-603nm)ofsolartwin&Sun’sspectra
ExampleofMagellanspectraof11solartwinsandtheSun(totalspectralcoverage3350A-1μm)
Meléndezetal.2009,ApJ,704,L66
Oursolarsystemisnothostbyatypical‘Sun’
Δ abundance: Sun-<twins>vs.atomicnumberZSuntypical:Δ =0Sunweird:Δ ≠0
Meléndezetal.2009
~ 0.08 dex ~ 20% CorrelaGonishighlysignificantprobability~10-9tohappenbychanceIt’smostlikelytowinthelo>ery
Sun’sanomaliesarestronglycorrelatedtothedustcondensaGontemperatureoftheelements!
Volatile elements
Dust condensation temperature (K)
Meléndez,Asplund,Gustafsson,Yong2009,ApJLe>ers
ThelateaccretedgasintheconvecGon
zonewasdeficientinrefractoriesThemissing
refractoriesmaybelockedintherockyplanetsandrockycoresofgiantplanets
Meléndezetal.2009
Timescaleproblemforplanetsignatures?InthestandardsolarmodeltheconvecGon
zoneshrinkstocurrentvalueaIerdiskisgone
Mamajek2009StandardsolarmodelSerenelli2011
Baraffe&Chabrier2010
MoreworkneededonaccreGonhistoryoftheearlySunandcomposiGonofaccretedmaterial
EpisodicaccreGon
Meléndezetal.2009
Areopenclusterschemicallyhomogeneous?
arXiv:1803.04461v1
M67:aboutsolarageandsolarmetallicity
SignaturesofatomicdiffusioninM67
Soutoetal.arXiv:1803.04461v1
Liu,Asplund,Yongetal.,inprep.
MoreevidencesofatomicdiffusioninM67
Turnoffstars
Subgiantstars
MoreevidencesofatomicdiffusioninM67
Liu,Asplund,Yongetal.,inprep.
Moreonchemicalhomogeneityofopenclusters:Pleiades.Analysisof5twinsstarsshowchemicalanomalies.Planetsignatures?When?Spinaetal.,submived
TucciMaiaetal.submived):starwithoutplanet(16CygA)is~0.03dexmoremetal-rich
Twinstarsinbinariescanalsobechemicalhomogeneousduetoplanets
16Cyg
Anotherbinarysystemwithabundancedifferences:XO-2.Bothstarshostplanets
Ramírezetal.2015.SeealsoTeskeetal.2015;Biazzoetal.2015
0.6MJ>0.3MJ+>1.4MJ
Teskeetal.2016
Conclusions
• ExtensivecalculaGonsofnon-standardstellarmodelsareurgentlyneededfordifferentapplicaGons,suchasthecosmologicalandsolarlithiumproblems,GalacGcchemicalevoluGon,asteroseismology,andtheplanet-starconnecGon
• ThenoGonofchemicalhomogeneityadoptedbychemicaltaggingischallengedbytheeffectsofatomicdiffusionandplanets
Sunswithwhitedwarfcompanions
Schirbeletal.2015
Dust from AGB star?
Schirbeletal.2015
SignaturesofformerAGBstar
Schirbeletal.2015Yisnotwell-reproducedbytheAGBmodels
Diverseabundancesignaturesunveiledinthesolartwin18Sco
asolartwinyoungerthantheSunandrichinrefractories,s-processandr-processelements
UsingUVspectraobtainedattheVLT/ESO
18Sco(brightestsolartwin,V=5.5)UVES+VLTR=110000(red)R=65000(blue)
Richinsilverandothern-captureelements
Richin
refractorye
lements
Age=2.9Gyr
Meléndezetal.2014,ApJ791,14August10,2014
SubtracGngTcondtrend
Meléndezetal.2014,ApJ
observations
AGB model (Amanda Karakas)
18Sco(brightestsolartwin,V=5.5)UVES+VLTR=110000S/N=800
Sr
Yb
Mo
Ru
Pd
Ag
YZr
Ba
La
Ce
Pr
NdSm
Eu
Gd
Dy
PerfectagreementbetweenresidualabundancesandpredicGonsfromtheSSr-processfracGons
Meléndezetal.2014,ApJ
Actually TWO lithium problems (Asplund et al. 2006): too much Li-6, too little Li-7
Asplund et al. (2006)
Li-6
Li-7 Expected primordial lithium
Lithiuminextremelymetal-poorstarsusingHIRESatKeck(10meter)
Stellar spectrum observed with Keck (exposure time of 5 hours)
Asplund&Melendez(2008)
hvp://www.aanda.org/arGcles/aa/abs/2013/06/aa21406-13/aa21406-13.html
3D+NLTEforLiandotherelements
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