A Primer on SZ Surveys

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A Primer on SZ Surveys. Gil Holder. Institute for Advanced Study. Outline. Sunyaev-Zel’dovich effect Upcoming surveys What’s next?. Optical Image of Cl 0016+16 (Clowe et al. 2000). ~ 7’. ~ 2 h -1 Mpc. Hot Gas in Cl 0016+16. (Reese). kT ~ 7.5 keV. Sunyaev-Zel’dovich Effect. I. - PowerPoint PPT Presentation

Text of A Primer on SZ Surveys

  • A Primer on SZ SurveysGil HolderInstitute for Advanced Study

  • OutlineSunyaev-Zeldovich effectUpcoming surveysWhats next?

  • Optical Image of Cl 0016+16(Clowe et al. 2000)~ 7~ 2 h-1 Mpc

  • kT ~ 7.5 keVHot Gas in Cl 0016+16(Reese)

  • Sunyaev-Zeldovich EffectCMBHot electronsCMB+IOptical depth: ~ 0.01Fractional energy gain per scatter: ~ 0.01

  • SZ Observables IAlong a line of sight:DEPENDS ONLY ON CLUSTER PROPERTIES !!!!Independent of redshiftTemperature weighted electron column densityUnique spectral signature

  • Non-Thermal SpectrumAbell 2163

    Data from 3 experiments

  • SZ Observables IIIntegrated effect from cluster: proportional to total thermal energy of electrons Temperature weighted electron inventory angular diameter distance, not luminosity distance

  • SZ Observables IIIIn reasonable units ( i.e., 1/h):Assume a virial relation:uncertainties come in mass limit as ^(0.6)

  • SZE RegularityCentral decrement vs Mass 40% scatterAverage SZ flux vs Mass 10% scatterMetzler ; astro-ph/9812295dTo

  • Searching for Galaxy Clusters Small area; very deep - AMI, AMIBA, BOLOCAM, SZA Large area; relatively shallow - ACBAR, PLANCK Large area; very deep - ACT, SPT

  • Mass LimitsFluxes at 30 GHzPLANCKSZA

  • ForegroundsCMB need good angular resolution and/or good spectral resolution; problem at all SZ frequenciesRadio point sources need good angular resolution for frequencies 200 GHzRadio halos and ghosts could be a problem at frequencies < 15 GHz

  • SZASurvey 10 square degrees to a few uK at resolution of 2-3 arcminutes at 30 GHzExpected mass limit ~Follow up catalog at 90 GHz for high resolution (
  • Example: RXJ1347-1145X-ray (colours)SZ (contours)SZ onlyReese

  • CMB contamination?? clusters are clearly at a different spatial scale close amplitudes means beam dilution catches up fast !!!Roughly 1 deg x 1deg labels are uK

  • Cosmology With the SZAHolder, Haiman & Mohr 2001

  • Dark Energy With the SZA 12 square degrees assume NO systematic errors assume redshifts measured to z=2

  • PLANCKSurvey the full sky to a few uK at resolution of 5-10 arcminutes at many frequenciesExpected mass limit ~Cluster detections will be unresolved point sources with SZE-like spectra1000 50000 clusters expected

  • Cosmology With PlanckBlack: all z

    Red: z

  • SPT/ACT/???Survey ~1000 square degrees to a few uK at resolution of 1-2 arcminutes at several frequenciesExpected mass limit ~Most powerful for cosmology5000 200000 clusters expected

  • Cosmology with the SPTHolder, Haiman & Mohr 2001

  • dN/dz for SPT

  • Dark Energy With the SPT Also sensitive to time dependent equation of state(Weller, Battye & Kneissl 2001)

  • Possible Plan of ActionUse AMI/AMIBA/BOLOCAM/SZA to define a significant SZE-selected sampleFollow up at many wavelengths: optical, X-ray, radio, cm, mm (including SZA!)Do a very large, deep survey for precise measurements of cosmological parameters

  • On the HorizonuK imaging between 30-400 GHz with arcminute resolution -- SPT, ACT, dedicated interferometers, ALMA, etc.New science opportunities & challenges -- peculiar velocities, -- spectral SZ -- CMB lensing

  • Peculiar Velocities (Kinetic SZ)Pure redshift, blueshift => thermal spectrumArcminutes scales => CMB ~ 1 uK -- CMB noise contribution = 10 km/s (0.01/)Other contamination: 50 km/s ? (Fischer & Lange 1993)

  • Relativistic Corrections

  • Lensing of the CMBTypical CMB gradient -- 15 uK/arcminTypical deflection angle -- ~ 0.1-1 arcmin(Seljak and Zaldarriaga )

  • SummaryNew cluster surveys coming soonDetailed follow-up will be required of some sample of SZE-selected clustersAmbitious survey machines in proposal stages could be extremely powerful

  • Gallery of SZ ImagesZ=0.83Z=0.14

  • Holder & Carlstrom 2001Green: shift in matter density by 10%

  • Counting Galaxy ClustersMass functionVolume element(Jenkins, Press-Schechter)Mass limit

  • Self-Similar EvolutionHolder & Carlstrom 2001

  • Effects of Gas EvolutionHolder & Carlstrom 2001

  • Angular Power Spectrum of SZ SourcesHolder & Carlstrom 2001