1 / 16

Study Systematics on the ICM metallicity measurements

Study Systematics on the ICM metallicity measurements. Elena Rasia Chandra Fellow Physics Department, University of Michigan, Ann Arbor. In collaboration with Mazzotta P., Moscardini L., Borgani S., Dolag K., Ettori S., Tornatore L., Bourdin H. (submitted ApJ).

bono
Download Presentation

Study Systematics on the ICM metallicity measurements

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Study Systematics on the ICM metallicity measurements Elena Rasia Chandra Fellow Physics Department, University of Michigan, Ann Arbor In collaboration with Mazzotta P., Moscardini L., Borgani S., Dolag K., Ettori S., Tornatore L., Bourdin H. (submitted ApJ) Columbus, Great Lakes Cosmology, June, 1st 2007

  2. Abell 2390 & MS2137.3-2353 Abell 1689 VIEWPOINT OF COSMIC WEB LABORATORIES OF THE ICM PHYSICS CLUSTERS OF GALAXIES Key quantities: Hydro-properties Gas density Temperature Pressure metals Key quantity: MASS http: //www.astro.unipd.it/~cosmo/ Dolag, Meneghetti, Moscardini, Rasia, Bonaldi, 06

  3. X-MASRasia et al. 07 Gardini et al. 04 See also: Mazzotta, et al 05, Rasia et al. 05, Rasia et al.06

  4. MILLENIUM SIMULATION WITH GAS 4000 Mpc/h X 62.5 Mpc/h Non-cooling simulation (Pearce, Gazzola et al., in prep) Preheating simulation In collaboration with R. Stanek (PI), Gus Evrard and Brian Nord - see talk by Gus Evrard. • Scaling relations and Covariance between M - Tx, fICM, YSZ, Lx …

  5. SIMULATIONS 275 Mpc Courtesy of Klaus Dolag Color: Temperature Borgani et al. 04 Metalicity treatment: Tornatore et al.07

  6. Galaxy Clusters as Laboratories for Stellar Evolution and History Sun like star Massive star

  7. CLUSTERS AS LABORATORIES FOR THE STELLAR EVOLUTION AND HISTORY http://chandra.harvard.edu/photo/2006/crab/index.html http://imagine.gsfc.nasa.gov/Images/icons/adv_snr.gif 1987A SN II irr CRAB NEBULAE SN II Chandra Comparison of Type Ia Supernova Remnants http://chandra.harvard.edu/photo/2007/kepler/index.html

  8. CLUSTERS AS LABORATORIES FOR THE STELLAR EVOLUTION AND HISTORY SNe IA PROGENITORS: white dwarf accreting matter from a nearby companion star Iron (major contributor), Silicon SNe II PROGENITORS: massive stars (with mass greater than 8 Msun ) -elements,as Oxygen, Magnesium, Silicon • [/Fe] gives indication of (SN Ia/ SN II) • [Si/Fe] gives indication of yields of SN Ia

  9. Silicon Profiles free frozen 6-9 keV 2-3 keV 1-2 keV Silicon profiles are well recovered for all the clusters in the sample

  10. Oxygen & Magnesium Profile free frozen 8-12 keV 6-9 keV For systems with T < 5 keV, we perfectly recover Oxygen. Magnesium is difficult to detect at all temperatures. Large and hot systems show a systematic overestimate of Oxygen and Magnesium lines.

  11. Interpretation: Oxygen and Magnesium At high temperatures, Oxygen and Magnesium are very weak. For both elements, slight changes in the continuum produce large deviation on the lines’ emissivity measurements. Plasma @ 8 keV Multi temperature nature of the plasma

  12. Iron profile 8-12 keV free frozen 2-3 keV Overestimate of Iron only for the cluster at temperature of 2-3 keV. Good agreement for hotter and colder systems. 1-2 keV

  13. Interpretation: Iron profile 1keV 4keV A 2-3 keV object is a combination of temperature: those larger than 2.5/3 give a large contribution to the Fe-K lines; those smaller, to the Fe-L lines => both groups of lines are pumped up by different-temperature plasmas

  14. Consequences • The systematic overestimate of Fe for systems of 2-3 keV can reduce the significance of the bump of Baumgartner et al. plot • Attention has to be paid to different • [/Fe] ratios… • and to their interpretation Baumgartner et al. 05

  15. KEY POINTS • Clusters are fantastic laboratories both for studying cosmology and for understanding the physics of the Intra Cluster Medium • Necessity of X-MAS to compare Simulations and Observations 1:1 • Simulations are now very powerful: large cosmological boxes are simulated with sophisticated physics.

  16. SUMMARY ON METALLICITY i) Silicon, ii) Oxygen for clusters cooler than 6 keV, iii) Iron for both cold systems (T < 2 keV) and hot systems (T > 4 keV) ARE WELL RECOVERED Due to the multi-temperature nature of plasma in clusters, the measurement of elements that have weak emission compared to the continuum IS NOT A SOLID AND ROBUST ESTIMATE Iron estimate for systems of 2-3 keV can likely be biased towards higher values since this is a critical temperature range where we mix together plasma presenting either strong Fe-L or strong Fe-K lines.

More Related