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Webster Cash University of Colorado MAXIM The Micro-Arcsecond X-ray Imaging Mission Collaborators • Ann Shipley, Randy McEntaffer, Steve Osterman at CU • Keith Gendreau, Nick White – Goddard • Marshall Joy – Marshall • Dennis Gallagher, Mike Leiber – Ball • The Maxim Team – http://maxim.gsfc.nasa.gov Maxim Heritage • 1995 – Future Concepts for X-ray Astronomy Chosen by Competition – Tananbaum, White, Gorenstein, Cash • 1996 – Leicester Meeting -- Observatories for 21st Century – Con-X and Xeus emerged as leaders – First Public Presentation on X-ray Interferometry (Deeper into 21st) • 1998 – Formation of Maxim Committee – Reviewed Feasibility – Set Imaging of Black Hole as Long Term Goal • 1999 – Creation of Fringes – Support from NASA Institute for Advanced Concepts • 2000 – Support from SEU and Decadal Committee Galaxies 22 AGN Jets SNR 18 Log Diameter (cm) Galactic Extra-Galactic Star Clusters 20 Clusters of Galaxies Interstellar 16 AGN BLR Sne 14 Interacting Binaries 12 Compact XRB Orbits Stellar Coronae 10 AGN Event Horizons GRB Afterglow CV XRB Disks 8 6 NS Disks 0 1 2 3 4 5 6 Log Distance (pc) 7 8 9 10 10 9 Clocks Earth GPB 8 Jupiter Orbit Binary Pulsar Log(Rc2/GM) 7 Eclipse Sun LIGO 6 5 Lens Galaxies 4 Sirius B 3 2 VLBI BLR M87 Maxim Pathfinder Strong Gravity 1 Event Horizon 0 6 4 2 0 Crab CygX-1 Maxim SgrA*/M87 LISA Con-X -2 -4 -6 Log Resolution (arcsec) -8 -10 -12 Capella 0.1” Capella 0.01” Capella 0.001” Capella 0.0001” Capella 0.00001” Capella 0.000001” AR Lac Simulation @ 100mas NASA/Dana Berry AGN Accretion Disk Simulations @ 0.1mas Courtesy of C. Reynolds, U. Maryland Need Resolution and Signal If we are going to do this, we need to support two basic capabilities: • Signal • Resolution X-ray Sources Are Super Bright Example: Mass Transfer Binary 1037ergs/s from 109cm object That is ~10,000L from 10-4A = 108 B where B is the solar brightness in ergs/cm2/s/steradian Brightness is a conserved quantity and is the measure of visibility for a resolved object Note: Optically thin x-ray sources can have very low brightness and are inappropriate targets for interferometry. Same is true in all parts of spectrum! Artist’s impression of Cyg X-1 (NASA) My Impression Status of X-ray Optics • Modest Resolution – 0.5 arcsec telescopes – 0.5 micron microscopes • Severe Scatter Problem – Mid-Frequency Ripple • Extreme Cost – Millions of Dollars Each – Years to Fabricate Pathlength Tolerance Analysis at Grazing Incidence A1 B1 sin B2 B1cos2 A2 OPD B1 B 2 B1 A1 & A2 in Phase Here B2 1 cos2 2 sin sin If OPD to be < /10 then 20 sin C d Baseline S2 S1 d focal 20 sin cos 20 sin 2 A Simple X-ray Interferometer Flats Detector Wavefront Interference =s (where s is fringe spacing) s d/L L s d Optics Each Mirror Was Adjustable From Outside Vacuum System was covered by thermal shroud X-ray Fringes 0.5keV Gendreau, October 2002 1.25keV Cash et al March 1999 Flats Held in Phase Sample Many Frequencies As More Flats Are Used Pattern Approaches Image 2 12 4 8 16 32 On the left is the probability distribution function for two sources in the same field of view. The central source has an energy half that of the source that is displaced to the lower left. The image on the right shows 9000 total events for this system with the lower energy source having twice the intensity of the higher energy source. Even though the higher energy source is in the first maxima of the other, the two can still be easily distinguished. Clockwise from upper left: Probability distribution; 100 photons randomly plotted; 9000 photons; and 5000 photons. Stars Simulation with Interferometer Sun with SOHO Maxim “The Black Hole Imager” 200 M CONSTELLATION BORESIGHT 10 KM COLLECTOR SPACECRAFT (32 PLACES EVENLY SPACED) CONVERGER SPACECRAFT 5000 KM DETECTOR SPACECRAFT 0.1mas Resolution 10,000cm2 Effective Area 0.4-7.0 keV Maxim Pathfinder 100mas Resolution 100cm2 Effective Area 0.4-2.0keV + 6keV Two Spacecraft Formation Flying at 450km Separation MAXIM Pathfinder Stowed – Internal Metrology Not Shown MAXIM Pathfinder in Deployed Configuration Primary and Secondary Optical Ring Layout Detailed View of Primary and Secondary Optical Rings Effect of Tilt 0.25 0.1 Percent encircled energy 0.12 0.1 Percent encircled energy Percent encircled energy 0.12 0.08 0.06 0.04 0.08 0.06 0.04 0.02 0.02 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 Angular distance from peak (mas) -6 -4 -2 0.15 0.1 0.05 0 0 0 0.2 0.1 0.2 0.3 0.4 0.5 0.6 Angular distance from peak (mas) 0.7 -3 -3 -2 -2 -1 -1 0 0 1 1 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 Angular distance from peak (mas) 0 2 2 2 4 3 3 6 -3 -6 -4 -2 0 2 4 Angular coordinates (mas) 6 -2 -1 0 1 2 Angular coordinates (mas) 3 -3 -2 -1 0 1 2 Angular coordinates (mas) 3 MAXIM Structural Dynamics Model -4 Magnitude response TF (lbf input/rad output) 10 -6 10 -8 10 -10 10 -12 10 0 10 1 2 10 10 • Frequency response curve shows first 50 structural modes • Damping of 0.5% assumed for all modes • Transfer function from RW force inputs to x and y tilt (2 curves) at focal plane - only largest TF in tip/tilt shown. • Thermal, RW and thruster disturbances to structural stability 3 10 Frequency (Hz) First 5 Structural Mode Shapes Tackling Full Maxim --- The Periscope Configuration Keeps beam pointed in constant direction like thin lens To focus Parallel to Source Direction Reduces Sensitivity to Baseline Each Periscope in the array is held to /20sin 10m Periscopes allow for delay in each channel. Can sample full UV plane. focus Integrated Mission Design Center Goddard Space Flight Center Delta IV 5m X 14.3m fairing Delta IV Heavy 5m X 19.1m fairing Propulsion/Hub SpaceCraft Sta. 7600 Delta IV 5m X 14.3m fairing Sta. 4300 Hub SpaceCraft/Detector SpaceCraft C.G. Sta. 2500 Sta. 1550 Propulsion/Hub SpaceCraft P/L Sta. 0.00 5/22/2017 40 Mission Sequence 1 km Science Phase #1 Low Resolution Launch Science Phase #2 High Resolution 200 km 20,000 km Transfer Stage Component Layout Detector Solar Array (4.5 m2) Comm Antenna (Ground/SpaceCraft 0.5 m) Thermal Shade (2.3 m2) Comm Antenna Comm Antenna (S/C to S/C 0.3 m) (Ground/SpaceCraft 0.5 m) CCD Electronics LOS laser receiver CCD Camera Hub/Detector Sensor Configuration Hub S/C Laser Beacon illuminates Detector S/C Super Star Tracker centers on Laser Beacon Detector S/C Super gyros hold inertial attitude Laser Detector measures range by time-of-flight of reflected laser beam Normal Star Tracker places Laser Beacon against fixed stars Coarse Ranging by omni RF comm link Reflector Cube reflects laser beam back to Hub for ranging Status: X-ray Interferometry in NASA Planning McKee-Taylor Report National Academy Decadal Review of Astronomy Released May 19, 2000 Prominently Recommends Technology Development Money for X-ray Interferometry Structure and Evolution of the Universe (SEU) Roadmap Major Goal of the “Beyond Einstein” Initiative Near Term Technology Program “X-ray Roadmap” to Image a Black Hole Imaging ROSAT Einstein Chandra 1000 times finer imaging Optimize MAXIM Parameters 100-1000 cm2 0.5 arc sec Constellation-X MAXIM Pathfinder 100 cm2 2 m baseline 100 marc sec Spectroscopy ASCA RXTE Do they exist? XMM Astro-E Where are they? 2000 Million times finer imaging MAXIM 1000 cm2 100-1000 m baseline 100 nas 3 m2 Indirect imaging via spectroscopy Conditions in the inner disk 2008 Spectrally Resolved X-ray Interferometry Demonstration Black hole Imager! 2014 2020