The perspective of X-ray galaxy clusters with the XIFU/Athena instrument Nicolas Clerc IRAP Toulouse, France AtomDB workshop 17, Athens, GA November 3rd 17
Clusters of galaxies ; large-scale structure Coherent model of structure formation Primordial fluctuations grow in expanding universe: Dark matter? Accelerated expansion? Emergence of cosmic web? (Planck) CMB = Primordial fluctuations Clusters of galaxies form last: Nature, origin of 1st structures? Physical mechanisms entering their formation? Galaxies form stars, cluster and change: Co-evolution of galaxy cluster components? Dark matter Gas density (simulation z= today )
Clusters of galaxies Massive objects 113 115 Msol 1 1 galaxies (~ 5 %) Hot gas (~15 %) s ~ 1 km s-1 CDM Last to form in the cosmic web Rare ~1- Mpc-3 Sizes ~ Mpc Representative content Hot gas = low-density plasma Highly ionized (e.g. Fe XXV line) Temperatures 17-8 K ~1 atom / liter e- mean free path ~ kpc Abundances.3 Z sol
Clusters of galaxies ; hot gas Sanders et al. (1) Perseus cluster Massive objects 113 115 Msol 1 1 galaxies (~ 5 %) Hot gas (~15 %) s ~ 1 km s-1 CDM Last to form in the cosmic web Rare ~1- Mpc-3 Sizes ~ Mpc Representative content Hot gas = low-density plasma Highly ionized (e.g. Fe XXV line) Temperatures 17-8 K ~1 atom / liter e- mean free path ~ kpc Abundances.3 Z sol
Clusters of galaxies ; hot gas Gravity Pressure hydro. Bulk motions Cooling (X) Pressure turb. Sanders et al. (1) Perseus cluster Massive objects 113 115 Msol 1 1 galaxies (~ 5 %) Hot gas (~15 %) s ~ 1 km s-1 CDM Last to form in the cosmic web Rare ~1- Mpc-3 Sizes ~ Mpc Representative content Hot gas = low-density plasma Highly ionized (e.g. Fe XXV line) Temperatures 17-8 K ~1 atom / liter e- mean free path ~ kpc Abundances.3 Z sol
Böhringer & Werner Thermal emission from the ICM Bremsstrahlung emission (continuum) + lines X-ray images give density distribution (squared) Morphology, shocks, cold fronts... Spectral shape provide temperature, metallicity Enrichment, cool-cores, feedback processes... And velocities, turbulent motions (e.g. Hitomi)
Large samples (13 15) upcoming X-ray surveys of increasing depth and sky coverage Courtesy MPE, erosita_de, XMM-XXL Galaxy clusters tracing the large-scale structure on Gpc scales NC et al. (1) ; NC+ in prep.
The Hot and Energetic Universe ATHENA Advanced Telescope for High Energy Astrophysics nd large class mission by ESA within its Cosmic Vision Programme To address the science themes of the Hot and Energetic Universe NASA GSFC Illustris simulation How does ordinary matter assemble into the structures we observe today? How do black holes grow and shape the Universe?
Athena and the X-IFU instrument Athena Mass ~7 tons Angular resolution 5 Power -8 kw Lifetime 5 yr (+5 yr) Effective area > 1. m @ 1 kev Orbit L Launch 8 Mirror technology Silicon Pore Optics
The X-ray Integral Field Unit X-IFU is the cryogenic high-resolution X-ray spectrometer for Athena It is developed under the leadership of IRAP and CNES (France) by a worldwide consortium Major contributions from Netherlands and Italy Belgium, Finland, Germany, Poland, Spain, Switzerland Japan and the US X-IFU Spectral resolution.5 ev (E<7 kev) Energy range.-1 kev Pixel size ~ 5 Field-of-view Hexagon Equiv. 5 arcmin Ø Non X-ray background < 5.1-3 cts/s/cm/kev Detector 38 TES
X-IFU science: broad & outstanding XIFU will measure the physical properties of hot plasmas Velocity, turbulence, metal abundances, ionization, density, temperature 3-D mapping of bulk motions, broadening and chemical composition XIFU will detect weak emission/absorption lines E.g. warm-hot intergalactic medium ( missing baryons ) XIFU detailed view on the physics of the hot and energetic Universe Metals and plasma diagnostics using lines AGN feedback processes and winds/outflows, black hole spins Stellar outflows, solar wind charge exchange... Barret et al. (1)
X-IFU cluster science
X-IFU cluster science Matter assembly through cosmic times Feedback processes Chemical enrichment Discovery science Pointecouteau, Reiprich et al. 13 ; Barret et al. 1 Ettori, Pratt, de Plaa, Eckert et al. 13
Address X-IFU science performances Assess the ability of the XIFU to recover actual complex physical information and meet the science requirements Case study of the assembly of structures Turbulence and bulk motions within clusters of galaxies Chemical enrichment of the ICM and evolution End-to-end simulations of representative datasets Encompass major complexities and richness of the data Optimize future observational strategies Work by Etienne Pointecouteau, Edoardo Cucchetti, Phillipe Peille, Veronica Biffi, Elena Rasia, Klaus Dolag, Stefano Borgani, Joern Wilms, François Pajot, Thien Lam Trong, Didier Barret, NC.
Simulation chain Cluster extracted from numerical simulations of structure formation Input is not existing in current observed datasets Input/output comparison 1 Emission model (b)vapec SIXTE1 simulation of the XIFU array [telescope+instrument transfer function] http://www.sternwarte.uni-erlangen.de/research/sixte/index.php Spatial binning following surface brightness + requirement of S/N per bin Full band spectral fitting in each bin with free parameters: temperature, redshift, abundances O, Si, Fe, broadening
Simulated mosaic
Temperature map (continuum) T (kev) 13 1 11 DEC (arcmin) 1 9 8 Measured Temperature (kev) 1 Silicon abundance ( Si/Si ) red =1.57 1 1 8.5..5 7 8 9 Input Temperature (kev) 1 11 7 RA (arcmin) Courtesy E. Cucchetti, E. Pointecouteau, P. Peille et al.
Bulk motions (line shift) Vbulk (km/s).15.1 Measured Redshift DEC (arcmin) Bulk motion speed (km/s) red =.8.155.15.15.1.135.13 5 5.13.135.1.15 Input Redshift.15.155.1 RA (arcmin) Courtesy E. Cucchetti, E. Pointecouteau, P. Peille et al.
O/Oʘ...5.5.3...3..1 RA (arcmin).1 Si/Siʘ RA (arcmin).8.7 DEC (arcmin) DEC (arcmin). Silicon abundance ( Si/Si ) DEC (arcmin)..5..3 Silicon abundance (Si/Si ) Fe/Feʘ Silicon abundance (Si/Si ) Courtesy E. Cucchetti, E. Pointecouteau, P. Peille et al. Element abundances..1 RA (arcmin) Pointecouteau, Reiprich et al. 13
Giant leap in sensitivity
More to end-to-end simulations Toy-models Emissivity Controlled input parameters (e.g. density profiles, turbulence level, temperature distribution, etc.) Separability of difficulties to ease development of hyperspectral analysis methods Velocity Analytic approaches Capture main characteristics of line measurement Fast derivation of statistical uncertainties (e.g. Kolmogorov spectrum sample variance, etc.) Line profile
Conclusions Athena mission is the next generation X-ray observatory from Europe. X-IFU: a technical challenge, a revolutionary instrument, a new window for breakthrough science. XARM will provide breakthrough insights and may lead to redefine science objectives Importance of simulations, modeling, data analysis tools and accurate atomic data Broad range of science, including baryonic matter assembly in the largest cosmic objects: clusters of galaxies. The X-IFU consortium works to build the best instrument to answer the needs of the community.
Thank you!