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X-RAY GROUPS WITH CHANDRA AND XMM: MASS, ENTROPY AND AGN HEATING. FABIO GASTALDELLO UC IRVINE & BOLOGNA D. BUOTE UCI P. HUMPHREY UCI L. ZAPPACOSTA UCI & TRIESTE J. BULLOCK UCI W. MATHEWS UCSC F. BRIGHENTI UCSC & BOLOGNA S. ETTORI BOLOGNA.
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X-RAY GROUPS WITH CHANDRA AND XMM: MASS, ENTROPY AND AGN HEATING FABIO GASTALDELLO UC IRVINE & BOLOGNA D. BUOTE UCI P. HUMPHREY UCI L. ZAPPACOSTA UCI & TRIESTE J. BULLOCK UCI W. MATHEWS UCSC F. BRIGHENTI UCSC & BOLOGNA S. ETTORI BOLOGNA
MASS PROFILES FOR A SAMPLE OF X-RAY BRIGHT AND RELAXED GROUPS • ENTROPY PROFILES FOR THE SAME SAMPLE. RELEVANT SCALE FOR BREAKDOWN OF SELF-SIMILARITY • AGN FEEDBACK IN AN INTERESTING OBJECTS • PRELIMINARY RESULTS ON A FLUX-LIMITED SAMPLE OUTLINE / MOTIVATION
Vikhlinin et al. 2006 Pointecouteau et al. 2005 • NFW a good fit to the mass profile • c-M relation is consistent with no variation in c and with the gentle decline with increasing M expected from CDM (α = -0.040.03, P05). Clusters X-ray results
THE PROJECT • Improve significantly the constraints on mass profiles and c-M relation by analyzing a wider mass range with many more systems, in particular obtaining accurate mass constraints on relaxed systems with 1012 ≤ M ≤ 1014 Msun • There were very few constraints on groups scale (1013 ≤ M ≤ 1014 Msun) • In Gastaldello et al. 2007 we selected a sample of 16 objects in the 1-3 keV range from the XMM and Chandra archives with the best available data
STARS GAS DM • After accounting for the mass of the hot gas, NFW + stars is the best fit model RESULTS MKW 4 NGC 533
No detection of stellar mass due to poor sampling in the inner 20 kpc or localized AGN disturbance RESULTS Buote et al. 2002 NGC 5044
c-M relation for groups We obtain a slope α=-0.2260.076, c decreases with M at the 3σ level
GAS FRACTIONS CLUSTERS GROUPS GASTALDELLO ET AL. 2007
COMPARISON WITH MASSIVE CLUSTERS AND GRAVITATIONAL SIMULATIONS PRATT ET AL. 2006
COMPARISON WITH MASSIVE CLUSTERS AND GRAVITATIONAL SIMULATIONS
AGN FEEDBACK IN GROUPS “UNFORTUNATELY, AGN HEATING IS NOT AS WELL STUDIED IN GROUPS AS IN CLUSTERS” (McNAMARA & NULSEN, ARAA). NGC 5044 IS BRIGHT AND NEARBY (z=0.009). IDEAL TARGET TO STUDY AGN FEEDBACK.
NGC 5044 AGAIN … CAON ET AL. 2000
DUST IN NGC 5044 TEMI, BRIGHENTI & MATHEWS 2007
Purely X-ray selected flux limited samples have been very effective in cluster studies (e.g.,Gioia+90,Edge+90,Rosati+95,Scharf+97,Vikhlinin+98,Romer+00,Bohringer+00) and they have follow-up studies with XMM or Chandra (REXCESS,400d2) • Groups have been historically selected in the optical band, only one pioneering study of 8 groups from the ROSAT NEP survey (Henry+95) • We used the NORAS catalogue: • 10h20m-14h region due to superior re-analysis • fx > 3x10-12 erg cm-2 s-1, completeness to better than 82% • Lx < 5x1043 erg s-1 • 15 objects, 5 in the archive, 10 observed with a Chandra LP (400ks, PI Buote) NOGS (NORAS GROUP SAMPLE)
NOGS (NORAS GROUP SAMPLE) A 1142 A 1185 A 1275 A 1377
NOGS (NORAS GROUP SAMPLE) NGC 5129 NGC 4104 A 1314 RXJ 022
NOGS (NORAS GROUP SAMPLE) A 1177 RGH 80
SUMMARY • DETAILED MASS PROFILES FOR A SAMPLE OF X-RAY BRIGHT GROUPS ARE WELL FITTED BY NFW+STARS. GAS FRACTIONS ARE LOWER AND WITH MORE SCATTER COMPARED TO CLUSTERS. • BROKEN POWER LAW BEHAVIOR OF ENTROPY PROFILES POINTS TO MORE IMPORTANT LOCAL MODIFICATIONS (AGN). • IT’S TIME TO STUDY AGN FEEDBACK IN GROUPS WITH MULTI-LAMBDA DATA. NGC 5044 CAN BE THE PERSEUS OF GROUPS. • RESULTS FOR A COMPLETE X-RAY SELECTED, FLUX LIMITED SAMPLE COMING SOON. IT’S IMPORTANT TO HAVE ALSO XMM DATA TO GO TO LARGE RADII.