Capabilities and Science Drivers for an X-ray Surveyor Mission Harvey Tananbaum (SAO) On behalf of the X-ray Surveyor community The Universe in High-resolution X-ray Spectra August 20, 2015 X-ray Surveyor Strawman Mission Concept • MSFC ACO Team Led by Randall Hopkins & Andrew Schnell • Strawman definition: Spacecraft, instruments, optics, orbit, radiation environment, launch vehicle and costing • Performed under the guidance of an informal mission concept team comprised by: J. A. Gaskin (MSFC), A. Vikhlinin (SAO), M. C. Weisskopf (MSFC), H. Tananbaum (SAO), S. Bandler (GSFC), M. Bautz (MIT), D. Burrows (PSU), A. Falcone (PSU), F. Harrison (Cal Tech), R. Heilmann (MIT), S. Heinz (Wisconsin), C.A. Kilbourne (GSFC), C. Kouveliotou (GWU), R. Kraft (SAO), A. Kravtsov (Chicago), R. McEntaffer (Iowa), P. Natarajan (Yale), S.L. O’Dell (MSFC), A. Ptak (GSFC), R. Petre (GSFC), B.D. Ramsey (MSFC), P. Reid (SAO), D. Schwartz (SAO), L. Townsley (PSU) The Strawman X-ray Surveyor Concept is a Successor to Chandra • Angular resolution at least as good as Chandra • Much higher photon throughput than Chandra Incorporates relevant prior (Con-X, IXO, AXSIO) development and Chandra heritage Limits most spacecraft requirements to Chandra-like Achieves Chandralike cost ($2.95B for Phase B through Launch) Optics & Instruments • High-resolution telescope • X-ray Microcalorimeter Imaging Spectrometer • High Definition Imager • Critical Angle Transmission Grating Concept Payload for: Feasibility Mass Power Mechanical Costing NOT THE FINAL CONFIGURATION Chandra X-Ray Surveyor Relative effective area (0.5 – 2 keV) 1 (HRMA + ACIS) 50 Angular resolution (50% power diam.) 0.5” 0.5” 4 Ms point source sensitivity (erg/s/cm2) 5x10-18 3x10-19 Field of View with < 1” HPD (arcmin2) 20 315 Spectral resolving power, R, for point sources 1000 (1 keV) 160 (6 keV) 5000 (0.2-1.2 keV) 1200 (6 keV) Spatial scale for R>1000 of extended sources N/A 1” Wide FOV Imaging 16’ x 16’ (ACIS) 22’ x 22’ 30’ x 30’ (HRC) Light-Weight, Sub-Arcsecond Optics • Build upon segmented optics approaches for Con-X, IXO, AXSIO - The segmented optics approach for IXO was progressing and a ~10″ angular resolution was demonstrated • Follow multiple technology developments for the reflecting surfaces Fabrication Alignment & Mounting Integration Optics – Specifications & Performance • Wolter-Schwarzschild optical scheme • 292 nested shells, 3m outer diameter, segmented design • 50×more effective area than Chandra Angular Resolution Versus Off-axis Angle E < 2 keV Short segments and WolterSchwarzschild design yields excellent wide-field performance. • 16x larger solid angle for sub- arcsecond imaging • 800x higher survey speed at the CDFS limit Chandra Surveyor - Flat surface - Optimum Adjustable Optics – Piezoelectric (SAO/PSU) Deposited actuator layer Outer electrode segment X-ray reflecting coating • • • • • • Micron-level corrections induced with <10V applied to 5–10 mm cells No reaction structure needed High yield — exceeds >90% in a university lab High uniformity — ~5% on curved segments demonstrated Uniform stress from deposition can be compensated by coating Row/column addressing • Implies on-orbit correction feasible • 2D response of individual cells is a good match to that expected Differential Deposition (MSFC/RXO) 7.1″ to 2.9″ (HPD – 2 reflections) in two passes Calculated HPD Profile pre- & post- correction 8 pre-correction post1-correction post2-correction arc seconds 500 Angstroms Angstroms 1000 0 -500 -1000 -1500 -2000 HPD (arcseconds) 1500 mm along surface 0 20 40 60 80 100 mm 120 140 160 180 7 6 pre-correction post1-correction post2-correction 7.08 7.1 5 4 3.68 3 3.7 2 1 0 2.87 2.9 Black Holes: From Birth to Today’s Monsters What is their origin? How do they co-evolve with galaxies and affect environment? Black Holes: What is the Nature of Their Seeds? Light seeds: Pop III star remnants, MBH~102 M☉ Collapse of nuclear star cluster, MBH~103 M☉ Massive seeds: Direct collapse of supermassive star or a quasi-star object, MBH~105 M☉ What is their origin? Sustained super-Eddington growth to MBH~104 M☉ Nature of Black Hole Seeds — First Accretion Light in the Universe Simulated 2x2 arcmin deep fields with JWST, X-ray Surveyor, and ATHENA • JWST will detect ~2×106 gal/deg2 at its sensitivity limit (Windhorst et al.). This corresponds to 0.03 galaxies per 0.5″ X-ray Surveyor beam (not confused), and 3 galaxies per ATHENA 5″ beam (confused). • Each X-ray Surveyor source will be associated with a unique JWST-detected galaxy. Limiting sensitivity, ~1×10-19 erg/s/cm2, corresponds to LX ~ 1×1041 erg/s or MBH ~ 10,000 M☉ at z=10 —well within the plausible seed mass range. • X-ray confusion limit for ATHENA is 2.5×10-17 erg/s/cm2 (5× worse than current depth of CDFS). Corresponds to MBH ~ 3×106 M☉ at z=10 — above seed mass range. Confusion in O&IR id’s further increases the limit (MBH~107 M☉ at z=8 per ATHENA Cycles of Baryons In and Out of Galaxies Generation of hot ISM in young star-forming regions. How does hot ISM push molecular gas away and quench star formation? How did the “universe of galaxies” emerge from initial conditions? Structure of Cosmic Web through X-ray observations of hot IGM in emission Galaxy Formation: The Nature of Feedback T~100,000 K T<10,000 K T>1,000,000 K 150 kpc Simulated 500 kpc box around a Milky Way type galaxy. ~ 40% of baryons are converted to stars, ~ 60% ejected outside ~ 30% observable in UV absorption ~ 30% heated to X-ray temperatures — unique feedback signature Required observations: detect and characterize hot halos around Milky Way-size galaxies to z~1. Required capability: ~ 100× sensitivity & angular resolution to separate diffuse emission from bright central sources What Physics is Behind the Structure of Astronomical Objects? Plasma physics, gas dynamics, relativistic flows in astronomical objects: •Plasma flows in Solar system, stellar winds & ISM via charge exchange •Supernova remnants •Neutron star (EOS) and particle acceleration in pulsar wind nebulae •Jet-IGM interactions •Hot-cold gas interfaces in galaxy clusters and Galactic ISM •Off-setting radiative cooling in clusters, groups & galaxies •… Required capability: high-resolution spectra and resolving relevant physical scales Capability Leap: High Throughput X-ray Gratings Spectroscopy Chandra HETG spectrum of NGC 3783. Note the wealth of emission and absorption lines with λ>~10Å (E<~1 keV) X-ray Surveyor gratings will provide R≈5000 and 4000 cm2 effective area: 250× throughput and 5× resolving power compared to Chandra Physics of the “New Worlds”, e.g: •Star-planet interactions & atmospheres of “hot Jupiters” •Stellar coronae, winds, & dynamos in sub-stellar regime Neutron star photospheres Inner workings of the black hole central engine, e.g: •spectroscopy of outflows •tidal disruption events (50× throughput and 20× resolving power compared to XMM Newton) New Capability: Add 3rd Dimension to the Data X-ray microcalorimeter will provide high-resolution, high throughput spectroscopy with 1 arcsec pixels — detailed kinematics, chemistry & ionisation state of hot plasmas Plasma Physics with Detailed 3D Tomography Unsharp mask image ripples with thin (< 1″) interfaces Chandra image of Perseus cluster: energy output from SMBH balances radiative cooling. Sound waves (in-plane motions) in viscous plasma (Fabian et al 2003)? Turbulence (line of sight motions) in stratified atmosphere (Zhuravleva et al 2015)? Athena X-ray Surveyor Key Goals: • Sensitivity (50× better Key Goals: •Microcalorimeter spectroscopy (R≈1000) •Wide, medium-sensitivity surveys Area is built up at the expense of coarser angular resolution (10× worse) & sensitivity (5× worse than Chandra) • • than Chandra) R≈1000 spectroscopy on 1″ scales, adding 3rd dimension to data R≈5000 spectroscopy for point sources ✓ Area Chandra is built up while preserving Chandra angular resolution (0.5″) ✓ 16× field of view with sub-arcsec imaging X-Ray Surveyor Science Workshop •Location: National Museum of the American Indian, Washington, D.C. •Date: October 6, 7, 8th •Website: http://cxc.harvard.edu/cdo/ xray_surveyor/ •Registration: $100 •Format: Invited + Contributed + Posters + Breakout Sessions Science Organizing Committee Jessica A. Gaskin (MSFC), Martin C. Weisskopf (MSFC), Harvey Tananbaum (SAO), Alexey Vikhlinin (SAO), Fabbiano Giuseppina (SAO), Christine Jones (SAO), Eric Feigelson (PSU), Neil Brandt (PSU), Leisa Townsley (PSU), Dave Burrows (PSU), Priya Natarajan (Yale), Maxim Markevitch (GSFC), Andrey Kravtsov (Chic.), Steve Allen (Stanford), Sebastian Heinz (Wisc.), Chryssa Kouveliotou (GWU), Roger Romani (Stanford), Feryal Ozel (Ariz.), Richard Mushotzky (UMD), Mike Nowak (MIT), Rachel Osten (STSCI) 2020 Decadal Prioritization • NASA Astrophysics Division white paper: Planning for the 2020 Decadal Survey • Provided an Initial list of missions drawn from 2010 Decadal Survey and 2013 Astrophysics Roadmap that includes the X-ray Surveyor • The three NASA Program Analysis Groups (PAGs) to coordinate community discussion to review and update list of missions • PAG reports will be sent to the Astrophysics Subcommittee and then to the Astrophysics Division for selection of mission concepts to study • Will result in a call for Science and Technology Definition Teams and assignment of lead NASA Center for each study http://cor.gsfc.nasa.gov/copag/rfi/ X-ray Surveyor • Scientifically compelling: frontier science from Solar system to first accretion light in Universe; revolution in understanding physics of astronomical systems • Leaps in Capability: large area with high angular resolution for 1-2 orders of magnitude gains in sensitivity, field of view with subarcsec imaging, high resolution spectroscopy for point-like and extended sources • Feasible: Chandra-like mission with regards to cost and complexity with the new technology for optics and instruments already at TRL3 and proceeding to TRL6 before Phase B Unique opportunity to explore new discovery space and expand understanding of how the Universe works and how it came to look the way we see it