Cosmic Momentum Field and Matter Cosmic Momentum Field and Matter FluctuationFluctuation

Study of Matter through Motions of GalaxiesStudy of Matter through Motions of Galaxies

2005. 5. 252005. 5. 25Changbom Park Changbom Park

(Korea Institute for Advanced Study)(Korea Institute for Advanced Study)

KIAS 050525KIAS 050525

Peculiar velocity vPeculiar velocity vpecpec

= Total velocity – Hubble expansion velocity (true distance)= Total velocity – Hubble expansion velocity (true distance)

Cosmic Velocity & Momentum FieldsCosmic Velocity & Momentum Fields

p = (p = (ρρ//ρρbb)v = (1+)v = (1+δδ) v &) v &

MotivationsMotivations

1. Mass fluctuation field1. Mass fluctuation field

2. Biasing (mass vs galaxy fields)2. Biasing (mass vs galaxy fields)

3. LSS free of redshift space distortions3. LSS free of redshift space distortions

4. Gravitational Instability4. Gravitational Instability

Our Local UniverseOur Local Universe

Overall PlanOverall PlanGalaxy Distance using redshift-independent Galaxy Distance using redshift-independent

distance indicatorsdistance indicators

xx & v & vrr((xx) of galaxies) of galaxies

PPρρ(k) &(k) & PPpp(k)(k)

ΩΩmm1.21.2 PPρρ(k) & (k) & ΩΩmm

0.60.6/b/b

‘‘Total’ Matter Distribution Total’ Matter Distribution Cosmological ModelsCosmological Models

Peculiar velocity vPeculiar velocity vpecpec

= Total velocity – Hubble expansion velocity (true distance)= Total velocity – Hubble expansion velocity (true distance)

Why should this work?Why should this work?

Distance IndicatorsDistance Indicators

* Tully-Fisher Relation : SpiralsSpirals (Luminosity – Circular Velocity)

* Dn-σ Relation : EllipticalsEllipticals (Diameter – Velocity dispersion)

(Distance error of ~ 20%)(Distance error of ~ 20%)

1. 1. Mark IIIMark III: ~3300 galaxies. TF & D: ~3300 galaxies. TF & Dnn--σσ indicators indicators AA82 + 7S88 + HMCL90-91-92 + W91PP + MAT92 + W91CL + CF92-93-9682 + 7S88 + HMCL90-91-92 + W91PP + MAT92 + W91CL + CF92-93-96

2. 2. SFISFI: 1216 Sbc~Sc galaxies: 1216 Sbc~Sc galaxies

SCISCI: ~800 galaxies in 24 clusters: ~800 galaxies in 24 clusters

3. 3. ENEARfENEARf: ~1400, T =<-2. B<14.5, cz < 7000km/s: ~1400, T =<-2. B<14.5, cz < 7000km/s

ENEARcENEARc: ~500, E & S0 galaxies in 28 clusters: ~500, E & S0 galaxies in 28 clusters

EFAREFAR: 736 early types in 85 clusters: 736 early types in 85 clusters

4. 4. KLUN+KLUN+: 6229 galaxies. cz<8000km/s: 6229 galaxies. cz<8000km/s

ObservationsObservations

Momentum Momentum FieldField

Momentum PS (prediction)

≈ Observed Momentum PS

β estimation73.0,27.0 m

72.0,0463.0 hb

p = (1+p = (1+δδ) v) v

SFI Galaxy SampleSFI Galaxy Sample Giovanelli et al. (1997)

1289 Spiral Galaxies with I-band Tully-Fisher Distance

SFI Main Galaxies + MAT Sample (δ < – 45º region, D ≥ 1.7')

661 Galaxies with D ≥ 1.7'

ENEAR Galaxy SampleENEAR Galaxy Sample1145 early-type galaxies with Dn-σ distances (mB<=14.5, cz <= 7000 km/s)

• 261 Groups/Clusters (734 gals)

• 364 Field Galaxies

merging (625 objects; |b|>15º)

Measuring Density & Momentum PSMeasuring Density & Momentum PS

jjrjj

j jr

jxkiexvwxWw

kp

)()(1)(

Fourier Transform

Power Spectrum

Density and Momentum Power SpectraDensity and Momentum Power Spectra

100 Mock Obs. (ENEAR)

Estimating Estimating ββ==ΩΩ0.60.6/b/b

2/10 )/)(/(

gPPHk P

At linear regime (>~ 80 h-1Mpc)

At quasi-linear regime (>~ 40 h-1Mpc)

)()()( predicobs kkPkP pp

ENEAR

SFI resultsENEAR

ENEAR vs SFIENEAR vs SFI

SFI

1:07.1: SFIENEAR bb

Comparison with Other ResultsComparison with Other Resultsββ E,SE,S σσ 88ΩΩmm

0.60.6 DataData MethodMethod Ref.Ref.0.460.46+0.06+0.06 -0.05-0.05 0.880.88 ENEARENEAR Mom. PSMom. PS This StudyThis Study

0.49 0.49 +0.08+0.08 -0.05-0.05 0.560.56 SFISFI Mom. PSMom. PS This StudyThis Study

0.500.50 ENEAR, IRAS PSCzENEAR, IRAS PSCz OMEOME Nusser et al. (2001)Nusser et al. (2001)

0.510.51 ENEARENEAR CFCF Borgani et al. (2000a)Borgani et al. (2000a)

1.101.10 ENEARENEAR MLML Zaroubi et al. (2001)Zaroubi et al. (2001)

0.60.6 SFI, IRAS 1.2 JySFI, IRAS 1.2 Jy OMEOME Da Costa et al. (1998)Da Costa et al. (1998)

0.420.42 SFI, IRAS PSCzSFI, IRAS PSCz VELMODVELMOD Branchini et al. (2001)Branchini et al. (2001)

0.820.82 SFISFI MLML Freudling et al. (1999)Freudling et al. (1999)

0.30.3 SFISFI CFCF Borgani et al. (2000b)Borgani et al. (2000b)

0.630.63 SFISFI MLML Silberman et al. (2001)Silberman et al. (2001)

0.510.51 0.560.56 MATMAT Mom. PSMom. PS Park (2000)Park (2000)

0.510.51 SFI+ENEAR, PSCzSFI+ENEAR, PSCz UMV (v-v)UMV (v-v) Zaroubi et al. (2002)Zaroubi et al. (2002)

0.570.57 SFI+ENEAR, PSCzSFI+ENEAR, PSCz UMV (d-d)UMV (d-d) Zaroubi et al. (2002)Zaroubi et al. (2002)

0.400.40 SNIa, IRAS 1.2 JySNIa, IRAS 1.2 Jy χ2χ2 fit fit Riess et al. (1997)Riess et al. (1997)

0.550.55 SNIa, PSCzSNIa, PSCz χ2χ2 fit fit Radburn-Smith et al. (200Radburn-Smith et al. (2004)4)

Future WorksFuture Works

1. All sky deep sample 1. All sky deep sample

2. Theories applicable to noisy but large samples 2. Theories applicable to noisy but large samples (2dF, SDSS, etc.) (2dF, SDSS, etc.)

3. Accurate distance estimator3. Accurate distance estimator

4. Cluster galaxy survey4. Cluster galaxy survey

5. Well-defined survey5. Well-defined survey

Era of Mass Era of Mass Fluctuation Fluctuation

Exploration !Exploration !