SZ/X-ray Joint Analysis of the ICM with APEX-SZ Data

Transcription

1 SZ/X-ray Joint Analysis of the ICM with APEX-SZ Data Kaustuv Basu (MPIfR Bonn / Universität Bonn) kbasu@mpifr-bonn.mpg.de with Martin Nord Yu-Ying Zhang Florian Pacaud & the APEX-SZ collaboration 1

2 The APEX-SZ Experiment Telescope 12 m ALMA prototype, located at 5100 m altitude in the Chilean Altiplano 8m Receiver 300 pixel TES bolometer, PI instrument on APEX, commissioned in Spring resolution, 0.4 deg 150 GHz About 7% sky time compared to SPT/ACT (often in bad weather!) 2

3 APEX-SZ Targeted Observations Bullet Cluster (Halverson et al. 2009) XMM J Data analysis & images by M. Nord (Ph.D. thesis, see also Nord et al. 2009) 3

4 Study of the Cluster Outskirts R 2500 (~ 0.3 R 200 ) ~ 0.5 Mpc X-Ray Strong Lensing R 200 ~ 1.5 Mpc SZ Effect Weak Lensing R 500 (~ 0.7 R 200 ) ~ 1.0 Mpc SZE ne Te X-Ray SZ Effect Weak Lensing Simulations by: Roncarelli, Ettori et al

5 Physics at the Cluster Outskirts Departure from thermodynamic equilibrium in the cluster outskirts (Te < Tgas) Rudd & Nagai 2009 Gas clumping creates opposite biases for the X-ray spectroscopic and SZ temperatures RXC J2228.6: Jia, Boehringer et al over-prediction of density ( SZ) 12 Mpc under-prediction of temperature 5

6 ICM Temperature De-projection X-ray ne 2 Λ(Te) SZE ne Te (SZE) observed ΔT(θ) (SZE) n e (r) T e (r) Abel's integral inversion to de-project density & temperature 6

7 De-projecting without Parametric Models We are trying out other methods of de-projection The only assumption for ICM modeling is spherical symmetry De-projection of the SZ map = the radial pressure profile! Fit here isothermal β GNFW Ameglio, Borgani et al. 2007, 2009 A2204: Basu et al

8 Multi-Frequency Observation of A2163 APEX-SZ XMM-Newton APEX-SZ + XMM-Newton = First non-parametric modeling (Nord, KB, Pacaud et al. 2009, A&A, 506, 623) Temp profile Gas fraction 8

9 Multi-Frequency Observation of A2163 APEX-SZ LABOCA 350 GHz APEX-SZ (150 GHz) + LABOCA (350 GHz) imaging of A2163 (Nord, KB, Pacaud et al. 2009, A&A, 506, 623) (y0,vr) constraints with new data 9

10 ICM Temperature De-projection Abell 2204 Archetypal relaxed cluster Basu, Zhang, Sommer et al., 2010, A&A arxiv: X-ray image with SZ contours SZ image with X-ray contours X-ray (XMM) SZE (Apex) 10

11 ICM Temperature De-projection Abell 2204 Archetypal relaxed cluster Basu, Zhang, Sommer et al., 2010, A&A arxiv: X-ray image with SZ contours SZ image with X-ray contours Density Temperature 11

12 ICM Temperature Analysis SZ SZ demonstration of falling gas temperature in the cluster outskirts Chandra Simulations ASCA Statistical + Systematics Statistical Projected ( spectroscopic-like ) temperature and re-calibrated Chandra (88 ks) measurement 12

13 Mass Modeling with the HSE Assumption of spherical symmetry and Hydrostatic Equilibrium Gas fraction in A2204 Cosmic fb Results for A2204 (Basu, Zhang et al. 2010) Total mass WMAP (Afshordi ea. 07) Gas mass Compare the fgas profile in A2204 (CC) with A2163 (merger) A

14 Comparison with the Lensing Mass XMM+Subaru, 5 relaxed Zhang et al Ongoing optical observation with the Wide Field Imager (B,V,R bands) at the La Silla 2.2 m telescope A2204 In works: Comparison of weak lensing and SZ/X-ray hydrostatic masses at large radii for APEX-SZ clusters (M.Klein, KB ea., in prep) 14

15 ICM Entropy profiles K = Te ne 2/3 Entropy is a fundamental indicator of heating/cooling in the ICM (it remains unchanged during adiabatic processes) Chandra (Sanders et al. 2008) Entropy at the cluster outskirts with Suzaku: George et al. 2009, Bautz et al. 2009, Kawaharada et al. 2010,.. Entropy profile in A2204 Basu, Zhang, Sommer et al. 2010, A&A 15

16 SZ confirmation of Entropy Floor Entropy comparison from SZ/X-ray imaging data Cavagnolo et al Difference of entropy in the central ~200 kpc Central entropies from Chandra data, taken from K. Cavagnolo s ACCEPT site Basu, Zhang, Sommer et al. 2010, A&A 16

17 Summary & Outlook Analysis of the intra-cluster medium (ICM) with resolved SZE maps have become a reality (some way to catch up with the sophistication and depth of the X-ray spectral analysis). We have performed non-parametric X-ray/SZE modeling of ICM properties in two clusters out to r 200. Stacking analysis in progress. Using APEX-SZ and XMM imaging data we were able to verify the existence of entropy floors in clusters, and also measure the decreasing gas temperature at the cluster outskirts (independently of X-ray spectroscopy). With better control of SZE statistical and X-ray background uncertainties, we can measure gas temperature beyond r 200 with available instruments. 17