determination of the hubble constant from x-ray and sunyaev-zeldovich effect observations of...
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DETERMINATION OF THE HUBBLE CONSTANT FROM X-RAYAND SUNYAEV-ZELDOVICH EFFECT OBSERVATIONS OF
HIGH-REDSHIFT GALAXY CLUSTERS
MAX BONAMENTE – UNIVERSITY OF ALABAMA IN HUNTSVILLEMARSHALL JOY – NASA MSFC
SAM LAROQUE, JOHN CARLSTROM – UNIVERSITY OF CHICAGO
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Sunyaev-Zel'dovich Effect Observations
OVRO
BIMA
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T CMB= f x ,TeT CMB∫T ne
k BT emec
2dl
Observable: Temperature decrement
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t al. (
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Clusters of similar mass have a redshift-independent SZE effect
X-ray Observations
Have SZE/X-ray available for 38 clusters, z=0.14-0.89 (Bonamente et al. 2006, ApJ 647, 25; LaRoque et al. 2006 ApJ 652, 917)
S X=1
4 1 z 4∫ ne2 ee dl
Observables: Surface brightness
CHANDRA (with BIMA decrement contours overlaid)
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T CMB= f x ,TeT CMB∫T ne
k BT emec
2dl
S X=1
4 1 z 4∫ ne2 ee dl
How to measure distances with X-ray and SZE observations
dl= d ⋅D A
Without assumptions on cosmological parameters, one can derive simultaneouslydistance DA and density ne of the emitting/scattering gas
Main advantages of this method: Independent of Cepheid calibration (no standard candles needed) Reaches high redshift (z~1)
Joint use of X-ray and SZE observations
CLUSTER Z CLUSTER ZCL 0016+1609 0.541 ABELL 1689 0.183ABELL 68 0.255 RX J1347.5-1145 0.451ABELL 267 0.230 MS 1358.4+6245 0.327ABELL 370 0.375 ABELL 1835 0.252MS 0451.6-0305 0.550 MACS J1423.8+2404 0.545MACS J0647.7+7015 0.584 ABELL 1914 0.171ABELL 586 0.171 ABELL 1995 0.322MACS J0744.8+3927 0.686 ABELL 2111 0.229ABELL 611 0.288 ABELL 2163 0.202ABELL 665 0.182 ABELL 2204 0.152ABELL 697 0.282 ABELL 2218 0.176ABELL 773 0.217 RX J1716.4+6708 0.813ZW 3146 0.291 ABELL 2259 0.164MACS J1115.2+5320 0.458 ABELL 2261 0.224MS 1054.5-0321 0.826 MS 2053.7-0449 0.583MS 1137.5+6625 0.784 MACS J2129.4-0741 0.570MACS J1149.5+2223 0.544 RX J2129.7+0005 0.235ABELL 1413 0.142 MAC J2214.9-1359 0.450CL J1226.9+3332 0.890 MACS J2228.5+2036 0.412MACS J1311.0-0310 0.490
SZE/X-ray sample
Models of the gas distribution
Use three models for the intra-cluster medium: (1) Simple isothermal beta model (2) Isothermal beta model with 100 kpc cut (3) Non-isothermal, hydrostatic equilibrium model with arbitrary temperature
profile and double-beta model density distribution:
Use a MCMC method, in which model parameters are used to predict the observables: surface brightness; temperature profile; SZE decrement;
then compare with the observations in order to do parameter estimation.
n e r= ne0 [ f ⋅1rr c1
2 −3 /21− f ⋅1rr c2
2 −3 / 2 ]
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on
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t al.
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) Examples of non isothermal modeling of intra-cluster
medium
SURFACE BRIGHTNESS
TEMPERATURE PROFILE
Hubble diagram (DA vs. z) for hydrostatic equilibrium model
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M=0.3, =0.7
H 0=76.9±3.43.9±8.0
10.02=31.6
M=0.3, =0.7
M=1.0, =0.0
H 0=76.9±3.43.9±8.0
10.02=31.6
H 0=73.7 ±3.84.6±7.6
9.5 2=53.9
H 0=77.6±4.34.8±8.2
10.12=53.1
H 0=67.1±3.64.5±8.0
10.02=32.5
“ [The SCDM fits] ... have the same quality as that for the currently favored CDM cosmology, indicating that cluster distances alone can not yet effectively constrain the energy density parameters...” (Bonamente et al. 2006)
Comparison of Hubble diagrams for all 3 models
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Other methods to measure the Hubble constant
Cepheid calibration of secondary distance indicators: Freedman et al. (2001)
H 0=72±3±7
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Cepheid calibration of supernovae type Ia (requires absolute calibrationof peak luminosity): Riess et al. (2004, 2005)
H 0=73±4±5
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iess
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20
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Indirect measurement from WMAP: Spergel et al (2007)
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perg
el et
al. (
20
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“ The CMB data do not directly measure H0; however , by measuring mH02
[...] the CMB produces a determination of H0 if we assume a simple flat CDM model” (Spergel et al. 2007)
After about 80 years, it all seems to hang together for the Hubble constant ...
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Summary:
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2006
CEPHEIDS SZE
Cepheid-based and SZE-based agree on Hubble constant , current uncertainty is 10-15%