APEX-Sunyaev-Zel dovich Observations

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1 APEX-Sunyaev-Zel dovich Observations Rüdiger Kneissl (ALMA / ESO) APEX: SZ-Camera, LABOCA Cluster Results with APEX SZ prospects with ALMA

2 The APEX-SZ Collaboration U.C. Berkeley / LBNL Brad Benson C.U. Boulder Hsiao-Mei Cho Amy Bender John Clarke Nils Halverson Daniel Ferrusca McGill University Bill Holzapfel Matt Dobbs Brad Johnson James Kennedy Zigmund Kermish Trevor Lanting Adrian Lee Onsala Space Martin Lueker Observatory Jared Mehl Cathy Horellou Tom Plagge Daniel Johansson Christian Reichardt Cardiff Paul Richards Peter Ade Dan Schwan Carole Tucker Helmuth Spieler ALMA/ESO(Santiago) Ben Westbrook Rüdiger Kneissl Martin White Oliver Zahn MPIfR Kaustuv Basu Rolf Guesten Ernst Kreysa Karl Menten Dirk Muders Martin Nord Bonn University Frank Bertoldi Matthias Klein Felipe Navarrette Florian Pacaud Reinhold Schaaf Martin Sommer MPE Hans Böhringer Gayoung Chon Rene Fassbender Robert Suhada

3 The Sunyaev-Zeldovich Effect Single Clusters Measures pressure along line of sight Peculiar velocities at high z Distances, H o, H(z) Cluster gas mass fractions, gas density and thermal structure, etc. Cluster Surveys "T SZ T CMB # $ n e T e dl integrated pressure = total thermal energy,, SZ redshift independence Measure growth of structure Cluster abundance and evolution are critically dependent on cosmology (dark energy)

4 Galaxy Cluster Science Galaxy Clusters Amy Bender talk Cluster Physics SZ Mass Calibration Cluster Cosmology Baryon, Dark Matter Density Temperature Distribution Ω m, σ 8, w(z),..

5 APEX-SZ overview APEX telescope: 12 meter ALMA prototype antenna 24 arc-min field of view 280 element TES Bolometer Array at 150 GHz 1 arc-min resolution 2D maps using circular scans up to 24 arc min diam. Probe to outskirts of low-z clusters Deep integrations with small footprints at ALMA location in Chile (Chajnantor in Atacama) high site, dry conditions multi-wavelength observations

6 The APEX-SZ Experiment PI instrument on APEX First light: December weeks/year observ. 280 TES Bolometer 150 GHz Demonstrates new technologies TES bolometers Frequency domain multiplexed readout Pulse-tube cooler to eliminate liquid cryogens NET ( ) µk CMB s 1/2 through better optical coupling ~1m

7 LABOCA on APEX Facility instrument since May 2007 provided by MPIfR 295 semiconducting composite 345 GHz higher resolution SZ: 18.6 arcsec beam with 11.4 arc-min FoV sensitivity per channel 75 mjy s1/2 observing modes: OTF, raster spiral, and now also fast photometry mode polarimeter planned

8 APEX-SZ Scan Strategy APEX => single cluster scans Circular drift scan pattern 20 circles, 5 second period arcmin/s scan speed No deadtime Constant ground pickup

9 Data Filtering and Transfer Function 0.2 Hz high pass filter removes low-frequency readout noise. Subtract cosecant(elev) + polynomial(t) (1 d.o.f. per circle) removes air mass signal and drift Remove spatial polynomial at each time step (Sayers et al.) Largely array average + tilt Data filtering is done to cluster simulated models (e.g. Beta) Accounts for transfer function Maps and radial profiles => transfer function corrected or source flagged

10 The APEX-SZ Bullet cluster (1E ) image 23 sigma detection Halverson et al no evidence for significant 150 GHz emission from GHz point source reported by Aztec. X-ray image with APEX-SZ (white contour and weaklensing (green contours) Jackknife noise map Mass-weighted SZ temperature = 10.8± 0.9 KeV

11 Bullet cluster model fit Beta model fit residual map Gas profile fit well by an isothermal elliptical beta model (adequate for sensitivity and resolution of these maps despite the complex nature of this system) Model parameters and gas-mass fraction consistent with those from X-ray data Zhang et al (2006): f gas = 0.161± (1.42 Mpc), Bradac et al (2006): f gas = 0.14±0.03 (4.9 x3.2 )

12 APEX-SZ and LABOCA imaging of A2163 APEX-SZ Nord et al LABOCA (345 GHz) + APEX-SZ + LABOCA

13 De-projected density and temperature profiles A2163: A merging cluster r 500 Isothermal Shaded region: xray (Squires et al., 1997) WMAP5 De-projected profile Consistent with XMM (Markevitch, Vikhlinin 2001) No parametric model such as Beta or Nagai, but inverse Abel transformation assuming spherical symmetry

14 A2204: A relaxed cluster Basu et al arxiv: r 500 r 200 APEX-SZ SZ profile SZ image with X-ray contours Temperature profile

15 Entropie A2204 Entropy is a fundamental property of the ICM, describing its history of heating and cooling Chandra 80 ks Abell 2163 Slope of the entropy profile near the cluster center determines the extent of non-gravitational heating Abell 2204

16 APEX 150 GHz Power Spectrum Reichardt et al sq degrees at 150 GHz, 12 µk RMS per 1 pixel Total Anisotropy < 105 µk 2 at 95%. σ 8 < 1.18 at 95% Accounting for non-gaussian statistics, Gaussian: σ 8 < 0.94 C l PS 1 x 10-5 µk 2 Agrees with Negrello prediction With BLAST 600 GHz data spectral index α= Agrees with MAMBO/SCUBA index, 2.65 Greve et al. (2004) Knox et al Dusty galaxies account for most power in APEX-SZ maps.

17 ALMA Atacama Large Millimeter/Submillimeter Array Three antennas at 5000m and six accepted Phase closure was the start of commissioning Jan 2010 Current bands are 3, 6, 7 & 9 Start of early science with 16 antennas in 2011 Completion of 66 antenna array in 2013 A world-wide Collaboration: +Chile

18 ALMA technical specifications

19 The population of sub-mm sources 5σ - 2h ALMA Knudsen et al ALMA simulation: Cluster SZ (red) and lensed submm sources (blue)

20 ALMA (Compact) Configurations

21 Simulated observation of a high-z cluster 90 GHZ Hydro-simulation of a merging cluster at z=1.5, each component with M = 1 x M. (courtesy of G. Tormen) ALMA ACA only ALMA sensitivity allows to get good images of high-z clusters in hours to day observations, also can probe non-thermal effects in cavities

22 Non-thermal electrons e.g Pfrommer et al 2005, Colafrancesco 2005, Scaife & Grainge 2010

23 The case for ALMA Band 1 (31-45 GHz) ALMA s excellent imaging quality should allow the mm-wave Sunyaev- Zeldovich (SZ) effect to be mapped in exquisite detail. Band 1 enables SZ imaging and together with band 2 enables detection of well-understood CO emission lines from the end of reionization. Estimated $7-10 M, technology straightforward, observing in higher PWV

24 Summary APEX-SZ is a 280 element 150 GHz bolometer array operating on the 12m APEX telescope Technology pathfinder role: TES bolometer array, multiplexed readout, no expendable cryogens. New SZ observations of the Bullet, A2163 and A2204 General consistency with expectations from x-ray. Future APEX-SZ Work Scaling relations -> cosmology calibration Detailed input to cluster modeling ALMA will offer unprecedented sensitivity and frequency range below 20 arc-sec scales for SZ imaging high-z clusters, pressure sub-structure sub-mm source environment, lensing