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COLD FRONTS IN CLUSTERS AND THE PECULIAR VELOCITY OF THEIR BCGs. FABIO GASTALDELLO INAF-IASF MILAN & UC IRVINE M. MESSA S. GHIZZARDI, M. ROSSETTI, D. ECKERT, S. DE GRANDI, S. MOLENDI. PECULIAR VELOCITY OF BCGs AND X-RAY THERMODYNAMICAL STATE / PRESENCE OF CFs
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COLD FRONTS IN CLUSTERS AND THE PECULIAR VELOCITY OF THEIR BCGs FABIO GASTALDELLO INAF-IASF MILAN & UC IRVINE M. MESSA S. GHIZZARDI, M. ROSSETTI, D. ECKERT, S. DE GRANDI, S. MOLENDI
PECULIAR VELOCITY OF BCGs AND X-RAY THERMODYNAMICAL STATE / PRESENCE OF CFs • THE IMPORTANCE OF ASSESSING SUBSTRUCTURES FOR THE ESTIMATES OF PECULIAR VELOCITIES: THE CASE OF A2626 OUTLINE
COZIOL+09 452 ABELL CLUSTERS W/ MORE THAN 10 MEMBERS VP OF BCG CAVAGNOLO+09 241 CLUSTERS K0 AS INDICATOR OF THERMODYNAMICAL STATE PECULIAR VELOCITIES OF BCGs AND X-RAY STATE CROSS-MATCH OF X-RAY PEAK AND BCG POSITION. ONLY IN EXTREME MERGERS (A754, A3376) LARGE SEPARATION. RESULTING SAMPLE OF 54 OBJECTS FG, Messa, et al. in prep
NCC CC PECULIAR VELOCITIES OF BCGs AND X-RAY STATE
VP OF BCGs AND X-RAY STATE KENDALL TEST: 93.2% KS TEST 97.7 %
ABELL 2626 82 MEMBERS CLEAR DETECTION OF SUBSTRUCTURES ALREADY IN MOHR+96 IT HOSTS A MINI RADIO HALO (GITTI+04) PEAK 1 CAVEAT: SUBSTRUCTURES ! PEAK 2 vcl: 17307 km/s 16533 km/s Vp: 802 km/s 27 km/s σv: 1057 km/s 658 km/s kT=2.9 keV
With CF NO CF VPEC OF BCGs AND X-RAY STATE A133 176 A1644 29 A1795 238 A496 55 A2029 61 A2052 185 A2199 156 CENTAURUS 125 A4059 27 A85 43 A478 340 A1068 127 A2107 187 A2556 85 A2626 802 27 A2717 107 A3112 215 A3581 31 ESO 3060170 20 MKW3S 27 A1361 204 A2667 382
COZIOL+09: “A large fractions of BCGs have significant peculiar velocity. This has one immediate consequence, which is that most clusters harboring a dominant galaxy are not dynamically relaxed” VAN DEN BOSCH+05: “The brightest galaxy in a dark matter halo is expected to reside at rest at the centre of the halo. In this paper, we test this `Central Galaxy Paradigm' (CGP) using group catalogues extracted from the Two-Degree Field Galaxy Redshift Survey (2dFGRS) and the Sloan Digital Sky Survey (SDSS). VPEC OF BCGs We show that the CGP is only consistent with the data in haloes with M < 1013 Msun, while in more massive haloes the data indicate a non-zero offset between the brightest galaxy and the satellites. This indicates that either central galaxies reside at the minimum of the dark matter potential, but that the halo itself is not yet fully relaxed, or, that the halo is relaxed, but that the central galaxy oscillates in its potential well.
VPEC OF BCGs Van den Bosch+05
MIRALDA-ESCUDE’+95: “The fact that cD galaxies often have large peculiar velocities relative to the average of the cluster galaxies has been used as an argument against their identification as cluster centers: however, clusters are continuously merging, and their density peaks do not need to coincide with their centers of mass. Substructure will cause the density peaks to move, in response to the gravitational forces of the infalling material” VPEC OF BCGs Abell 383 Richard+11
OFF-AXIS MERGERS INDUCING COLD FRONTS CAN EXPLAIN SPEEDING BCGs ALSO IN RELAXED CLUSTERS: NEEDS FURTHER INVESTIGATION TAKING CARE OF POSSIBLE SUBSTRUCTURES • PECULIAR VELOCITIES OF BCGs FITS NATURALLY IN A HIERARCHICAL PICTURE OF STRUCTURE FORMATION AND SLOSHING/COLD FRONTS ARE AND X-RAY SIGNATURE SUMMARY
COLD FRONTS AND METALS ANISOTROPIES IN ZW 1742+3306 STEFANO ETTORI OBSERVATORY OF BOLOGNA F. GASTALDELLO, M. GITTI, E. O’SULLIVAN, M. GASPARI, F. BRIGHENTI, L. DAVID, A. EDGE
AGN METAL OUTFLOWS Kirkpatrick+11
AGN METAL OUTFLOWS Kirkpatrick+11
AGN METAL OUTFLOWS Kirkpatrick+11
SLOSHING CAN’T DO IT ... Roediger+11
VERY STRUCTURED COLD FRONT IN ZW1742: KH INSTABILITY • ANISOTROPY IN THE METAL DISTRIBUTION: AGN MOST LIKELY, HOWEVER CAN SLOSHING DO IT ? SUMMARY