AXIS Mirror Assembly (AMA) William W. Zhang NASA Goddard Space Flight Center

Transcription

1 AXIS Mirror Assembly (AMA) William W. Zhang NASA Goddard Space Flight Center William W. Zhang AXIS Mtg at UMD 1

2 Next Generation X-ray Optics Team K.D. Allgood 1, M.P. Biskach 1, J. Bonafede 1, K.W. Chan 2, M. Hlinka 1, J.D. Kearney 1, L.D. Kolos, J.R. Mazzarella 1, G. Matthews 3, R.S. McClelland 1, H. Mori 2, A. Numata 1, T. Okajima, L.G. Olsen, R.E. Riveros 2, T.T. Saha, P.M. Solly 1, W.W. Zhang NASA Goddard Space Flight Center 1 Stinger Ghaffarian Technologies, Inc. 2 University of Maryland, Baltimore County 3 ATA Aerospace, LLC Collaboration with MIT, MPE, and OAB is beginning. Funded by NASA through GSFC/IRAD, ROSES/APRA, and ROSES/SAT. William W. Zhang AXIS Mtg at UMD 2

3 The Meta-Shell Approach Metashells Mirror Segment s Assembl y Heritage from Chandra, XMM-Newton, Suzaku, & NuSTAR. William W. Zhang AXIS Mtg at UMD 3

4 How to Build a Meta-Shell? Animation by Britt Griswold and Jay Friedlander 4

5 Visualizing AMA 0.4m 1.8 m Primaries Secondaries Stray-light baffles Thermal Baffles & Spider web Mass: ~450 kg William W. Zhang AXIS Mtg at UMD 5

6 Key Parameters of AMA Parameters Focal length Inner diameter Outer diameter No. of meta-shells 6 9 m 0.3 m 1.7 m No. of mirror shells 298 No. of mirror segments 16,568 Mass of AMA, incl. stray-light baffles, thermal baffles, and mounting structures Unobstructed FOV diameter Effective areas, not accounting for detector QE 454 kg 10 arc-mins 7,700 cm 1 kev 1,626 cm 6 kev 184 cm 12 kev Values William W. Zhang AXIS Mtg at UMD 6

7 PSF vs. Off-Axis-Angle Flat Focal Surface Optimal Focal Surface Reality will be somewhere between these two extremes. William W. Zhang AXIS Mtg at UMD 7

8 AMA Top Level Error Budget Fabrication Meta-Shell Construction Integration of Meta-shells to AMA Ground to Orbit Effects Coating 0.10 Alignment 0.10 Bonding 0.10 Alignment 0.10 For a pair of mirrors. Based on normal incidence mea coating, and on x-ray measurement. This number for a pair of primary and secondary mirr mirror settling. Based on Hartmann measurement co This number for a pair of mirrors, including applicatio to bonding. Based on finite elment analysis and mode measurement using x-rays. This number respresents the ability to orient and tran Based on optical Hartmann measurement and fiducia Attachment 0.10 Based on optical alignment verification and end-to-en Launch shift 0.10 Gravity release 0.10 Based on finite element analysis and modeling suppo term stability. Based on finite element analysis and modeling which measurement of large numbers of trials of individual respect to gravity. On-orbit thermal 0.10 Based on thermal modeling and analysis. On Orbit Performance (RSS) 0.33 This is the on-axis performance of XMA on orbit. Add the final obervatory-level PSF. William W. Zhang AXIS Mtg at UMD 8

9 Four Technical Elements Mirror fabrication Grind and polish Finish with an ion-beam Coating Sputter iridium with a magnetron Eliminate stress Alignment Fine-tune the heights of spacers Settle the mirror into alignment with acoustics Bonding Bond the mirror to its four spacers with adhesive William W. Zhang AXIS Mtg at UMD 9

10 Technology Status Mirror fabrication Consistently making 0.6 mirrors Expect to reach 0.2 or better by 2019 Coating Doing ~1 At least two different methods are being investigated, one at GSFC and the other at MIT Alignment Doing ~1 or slightly better Expect to reach 0.5 by late 2018 and 0.2 by 2019 Bonding Doing ~1 or slightly better Expect to reach 0.5 by later 2018 and 0.2 by 2019 William W. Zhang AXIS Mtg at UMD 10

11 Recent X-ray Test Result Secondary Mirror Primary Mirror Silicon Plate Two uncoated mono-crystalline silicon mirrors aligned and bonded on a silicon platform Full illumination with Ti-K X-rays (4.5 kev) William W. Zhang AXIS Mtg at UMD 11

12 Three Prongs of Development Single-Pair Modules (TRL-4) Multiple-Pair Modules (TRL-5) Meta-Shells (TRL-6) Objectives: 1. Debug and verify mirror fabrication process. 2. Debug and verify the basic elements of alignment & bonding procedures. Timeline: 2017: 3 HPD 2018: 1 HPD 2019: 0.5 PD 2020: ~0.2 HPD Objectives: 1. Debug and verify coalignment process. 2. Conduct environmental tests: vibration, thermal vacuum, and acoustic. Timeline: 2018: 3 HPD 2019: 1 HPD 2020: 0.5 HPD 2022: ~0.2 HPD Objectives: 1. Debug and verify every step of meta-shell manufacturing process. 2. Validate production schedule and cost estimates. Timeline: 2019: 3 HPD 2020: 1 HPD 2022: 0.5 HPD 2024: ~0.2 HPD William W. Zhang AXIS Mtg at UMD 12

13 Cost of Making AMA Part of a credible case for AXIS must include a reasonable cost estimate for making AMA. We must provide concrete empirical evidence for the cost estimating professionals to arrive at a reasonable number. Here is the beginnings of documenting a case: Each mirror substrate production costs $2000 in labor, and $2000 in material and equipment. Each mirror costs $1000 in labor to align and bond and $1000 in equipment and material. AXIS s ~20,000 mirror segments cost: $120M Each meta-shell costs $5M to test and quality. AXIS s 6 meta-shells cost $30M to test and qualify. The alignment and integration of the 6 meta-shells costs $20M AMA cost: $120M + $30M + $20M = $170M. William W. Zhang AXIS Mtg at UMD 13