Download BOSS DR12: Clustering of galaxies &Dark Matter halos Sergio Rodríguez-Torres

BOSSDR12:Clusteringof
galaxies&DarkMatter
halos
SergioRodríguez-Torres
Instituto deFísica Teoría – UniversidadAutónoma deMadrid
SnowPAC – GalaxyHaloconnection
Snowbird,Utah
Outline
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Motivation
BaryonOscillationSpectroscopicSurvey(BOSS)
HaloAbundanceMatching
MultiDark simulation&Ingredientsofthemodel
BOSSclustering:ModelvsData
OtherHAMimplementations
Summary
Motivation
SDSSDR93Dmap
MultiDark PlanckSimulation
Motivation
• Finding links between the
DM and the Galaxy
distributions.
• Increasing the knowledge
of the galaxy formation
physics.
• Different methods to
connect DM halos and
galaxies.
SDSSDR93Dmap
Motivation
• Finding links between the
DM and the Galaxy
distributions.
• Increasing the knowledge
of the galaxy formation
physics.
• Different methods to
connect DM halos and
galaxies.
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Mock Galaxy catalogs
Covariance matrices
Prepare new surveys
New
data
requires
increasing the resolution
and the precision of
mocks
SDSS-III
• SDSS-IIIconsistsinfoursurveys:
Ø BOSS:redshiftsurvey(LargeScale
Structure)
Ø SEGUE-2:Opticalspectroscopic
survey(Milkyway)
Ø APOGEE:Infraredspectroscopic
survey(MilkyWay)
Ø MARVELS:Multi-objectradial
velocityplanetsearch
• Startedin2008andfinishedin2014withthefinal
datarelease12.
BaryonOscillationSpectroscopic
Survey(BOSS)
• MapLRGandQuasarsinthe
lowredshiftregion.
• Detectionofthebaryonic
acousticoscillations.
• 10000squaredegrees
• ~1.5millionsofluminous
galaxies
• Redshift0.15to0.75
Andersonetal.2014
CMASS/LOWZ
• LOWZ:brightestand
reddestgalaxiesatlow
redshift(0.15-0.43),
extendingtheSDSS-I/IILRG.
• CMASS:Designedtoselect
galaxiesathighredshift
(0.43-0.75),mostofthem
LRG
GalaxyclusteringofBOSS
• Goal: Construct a light-cone for the full CMASS-NGC
sample
• Assign galaxies to dark matter halos
• Stellar mass function
• Fix the linear bias of our galaxy population to
reproduce observations
• Incompleteness of the sample
• Fiber collisions
• Selection function of the sample (Angular and
radial)
Methods
• HydroSimulations
ØComputationallyexpensive
• Semi-AnalyticalModels(SAM)
ØLargeNumberofparameters
• HaloOccupationDistribution(HOD)
• Oneofthemostcommonmethods
• ProbabilitytofindNgalaxiesinahosthalowithmassM
• ~5parameterstofixtheclustering
• HaloAbundanceMatching
• Matchtheobservedluminosity/stellarmassfunction
withthehalodistribution
HaloAbundanceMatching
HaloAbundanceMatching
• Scatter between DM halos
and galaxies should be
constraint from the data
• Direct impact on the
clustering
• Velocity
dispersion
–
stellar mass (luminosity)
• Circular velocity – stellar
mass (luminosity)
HaloAbundanceMatching
Reddicketal.,2013
HaloAbundanceMatching
Weapplyscatterto
thecircularVelocity
new
Vpeak
= (1 + N (0, ))Vpeak
Newvelocitydistribution
Sortnewvelocitiesanddoa
monotonic matchusing
stellarmassdistribution
• Basicassumption:Massivegalaxies
followmassivehalos
Ingredientsofthemodel
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GalaxyCatalog
Darkmattersimulation
ObservedStellarmassfunction
Stellarmassdistribution
Surveyfeatures:Masks,selectionfunction
Fibercollisions
MultiDark suitesimulations
Klypin etal.2015
TheBigMultiDark PlanckSimulation
• 2.5Gpc/h,3840^3
• 20snapshotsbetweenredshift
0.43-0.7
• RockStar halofinder(Satellites
andcentrals)
• PlanckCosmology
www.multidark.org
StellarMassFunction
Portsmouth DR12 SM catalogs
(Maraston et al. 2013)
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Compele Stellar Mass catalog at
low mass
StellarMassIncompleteness
Ø Once galaxies are assigned to the dark matter halos it is
necessary to take into account the incompleteness of the
sample.
Reproducingselectionfunctionand
geometry
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Angularmask
Angularcompleteness
Radialselectionfunction
Vetomasks
Randomgeneration
FiberCollisions
Guo,Hong.etal.2012
• Aproblemofusingfibersisthatthefinitesizeofthe
fiberplugspreventstwofibersfrombeingplacedtoo
closetooneanotheronthesameplate
62”istheminimumseparation
betweenfibers
Fixingthescatterparameter
2-ptcorrelationfunction
Remaining Systematics errors?
• Selectioneffects
• Dependency oftheintrinsic
scatterwithstellarmas
• Offcenteringgalaxies
• …
Quadrupole
RedshiftevolutionoftheCMASSsample
PowerSpectrum
3-ptcorrelationfunction
HaloMassandStellarMass
HaloOccupationDistribution
Summary
• We produced a galaxy catalog from simulations that reproduce
the stellar mass function and correlation function in
configuration space.
• The light-cone reproduces the survey geometry, radial
selection function, stellar mass incompleteness and fiber
collisions effect.
• HAM provides good predictions for 2-point and 3-point
statistics, using one single parameter.
• Halo occupation distribution and halo to stellar mass relation
are in agreement with previous works.
• Modification of the standard HAM can be a powerful tool to
study the clustering of incomplete population samples.
HAM:Alternative
implementations
• One single and constant parameter is not enough
to describe all observations.
• There are alternatives in order to handle this
problem of HAM such as velocity bias, age
matching, assembly bias, etc.
• Scatter can be different for central and satellites
halos, it’s possible as well control the fraction of
satellites in our sample.
ELG-HAM
• New surveys increase the data of ELG and QSO
• In order to prove cosmological models, it is
necessary to take into account the incompleteness
of those samples
• Using abundance matching with a probability
function it is possible to study the occupation
distribution of the sample (Favole et al. 2015)
!
!!!!!!Mmean=12.0,!fsat=0.225!
!!!!!!ELG!!
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!!!!!!Mmean=12.0,!fsat=0.225!
!!!!!!ELG!!
!
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Favole etal.2015
CurrentandFutureprojects
• Extend model to study incomplete samples as ELG
and QSO for eBOSS and future surveys
• Study our current method to populate galaxies
using intrinsic samples of galaxies.
Thankyou!