1. THE OUTSKIRTS OF THE NGC 5044 GROUP
FABIO GASTALDELLO
INAF-IASF MILAN
D. BUOTE, F. BRIGHENTI, W. MATHEWS, D. ECKERT, M. ROSSETTI, S. MOLENDI, S. GHIZZARDI, S. DE GRANDI, S. ETTORI

2. WHY DO WE CARE ?
OUTSKIRTS OF GALAXY GROUPS ARE LESS WELL EXPLORED THAN CLUSTERS (SUN+09 AT LEAST TO R2500, ONLY 7 AT R500, MEDIAN COVERAGE IN THE OUTERMOST ANNULUS 42%)
THEY ARE MOST AFFECTED BY NON-GRAVITATIONAL PROCESSES SO THEY ARE AN EXCELLENT VENUE TO STUDY THOSE IN PARALLEL WITH CLUSTERS
ABUNDANCE IS EVEN MORE KEY: GIVEN THAT MUCH OF THE EMISSION IN THE KeV BAND IS DUE THE Fe-L SHELL, YOU HAVE ABUNDANCE-NORMALIZATION DEGENERACY IF YOU DON’T GET THAT RIGHT (AND THAT IS AFFECTING PRETTY MUCH EVERYTHING: MASS, ENTROPY, …)
NGC 5044 IS THE PERSEUS OF GROUPS

3. WHAT WE KNOW ABOUT METALS
SUN 12

4. WHAT WE KNOW ABOUT METALS
JOHNSON+11

5. WHAT SUZAKU EXPLORED
SASAKI+14

6. WHAT SUZAKU EXPLORED
SASAKI+14

7. WHAT WE HAVE DONE WITH XMM
BUOTE+04

8. WHAT WE HAVE DONE WITH XMM
BUOTE+04

9. WHAT WE HAVE DONE WITH XMM

10. WHAT WE HAVE DONE WITH XMM

11. WHAT WE HAVE DONE WITH XMM

12. COULD BE SLOSHING ?
GASTALDELLO+09,+13 DAVID+09
O’SULLIVAN+14

13. Beyond the (cool) cores: large scale sloshing in the ICM
Mpc-scale cold fronts have been discovered in the outskirts of A2142 (Rossetti+13), Perseus (Simionescu+12), RXJ (Walker+14). Are they a peculiar feature of these three systems or a common feature of clusters ?
A85 XMM residual map
Systematic search of excesses in the residual maps with ROSAT/PSPC images: 5 other systems show large scale (>400 kpc) features
Large scale excesses confirmed with deeper new XMM-Newton observations
Are there cold fronts ?
Large scale excess
Small scale
known cold fronts
Subclusters
Subclusters
Stay tuned! Rossetti et al. in prep.

14. SI/Fe RATIO IN GROUPS

15. THE CASE OF NGC 2300
RASMUSSEN+06
RASMUSSEN & PONMAN 07

16. SUMMARY
ABUNDANCE MISTERY IN NGC 500 NEEDS TO BE SOLVED WITH A COMPLETE XMM MOSAIC
AS A MORE GENERAL APPROACH A SAMPLE OF BRIGHT NEARBY GROUPS NEED TO BE ABSORBED TO CONSTRAIN BOTH THERMODYNAMICAL AND CHEMICAL PROPERTIES
SUZAKU NO LONGER IN OPERATION, CHANDRA WITH LOW ENERGY RESPONSE AFFECTED BY A CONTAMINANT, XMM WILL NEED TO BE EXPLOITED