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Soft X-ray and X-ray multilayers for Chinese Telescopes Zhanshan Wang Institute of Precision Optical Engineering (IPOE) School of Physics Science and Engineering Tongji University, Shanghai 200092, China Outline Soft X-ray Polarimetry with LAMP Multilayers for LAMP X-ray Timing and Polarization(XTP) project Depth-graded multilayers for XTP Summary and outlook In the late 1970’s Chinese Academy of Sciences launched a X-ray telescope project and in the early 1980’s, it was cancelled. There were nearly no any experience in China on making grazing incidence X-ray telescopes In 2004, the plan for exploring Moon was started. In 2007, a EUV telescope worked on the Moon was planned. On Dec. 2, 2013, the EUV telescope was launched and now is in the orbit. [email protected] for He-II , [email protected] for He-I A EUV telescope on the moon 30.4nm imaging of magnetosphere 58.4nm light from ionsphere [email protected] for He-II , [email protected] for He-I 1 periodic Mg/SiC multilayer aperiodic Mg/SiC dual-function multilayer [email protected],[email protected] (a) Reflectivity 0.1 0.01 1E-3 1E-4 20 30 40 50 Wavelength (nm) 60 70 Soft X-ray Polarimetry with LAMP Lightweight Asymmetry and Magnetism Probe (LAMP) LAMP is in the framework of a small satellite unpolarized E polarized Soft X-ray Polarimetry with LAMP Science with LAMP • Pulsars – To measure the geometry of B-field – To constrain the equation of state – Be able to identify “bare quark stars” • Relativistic jets in Blazars – To measure the B-field in the X-ray jet • Black hole binaries and active galactic nuclei – To measure the disk inclination and help constrain BH spin Multilayers for LAMP Soft X-ray Y Using multilayer mirrors working at ~250 eV Parabolic Surface θ Camera p/2 P Surface A O Total collection area : 1300cm2 201.39 40° 286.03 X 50° Multilayers for LAMP Multilayers for LAMP The incident angle is different at different positions of the surface incidence angle(degree) 52 50 field:0 degree 48 46 44 42 At central field, the incident 40 angle is in the range from 40 38 200 220 240 260 X-coordinate(mm) 280 300 to 50 degrees Multilayers for LAMP 1 3.91 3.27 3.32 3.37 3.43 3.48 3.55 3.61 3.68 3.75 3.83 Cr/C multilayer Reflectivity 0.1 0.01 N=120 1E-3 D=3.27-3.91nm 1E-4 Rs=23%~26%~31% 1E-5 at =0.45-0.4-0.3nm 1E-6 1E-7 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 Incidence Angle(deg) Multilayers for LAMP 0.010 0.27% Magnetron Sputtering Target size 125mm450mm D/D 0.005 0.000 -0.005 -0.010 0 20 40 60 80 100 120 X position (mm) 140 160 180 200 Multilayers for LAMP Near-normal Incidence Reflectance Cr/C multilayers,D=2.3nm 0.14 N=250 N=300 0.12 Reflectance, R (a.u.) Reflectance, R E=8.05keV N=150 N=200 N=250 0.10 0.08 0.06 0.04 0.02 N=300 0.00 44.2 0 1 N=200 N=150 2 3 4 44.4 44.6 44.8 45.0 45.2 45.4 Wavelength, (angstrom) Grazing Incidence Angle, (degree) Multilayers for LAMP, D=3.27-3.91nm period is larger than that at normal incident The multilayers were made for LAMP and are waiting for polarization measurements X-ray Timing and Polarization(XTP) project The X-ray Timing and Polarization (XTP) mission, proposed by IHEP, is currently being developed in China to explore some main physical problems by observing the Black Holes and other compact objects. X-ray Timing and Polarization(XTP) project X-ray rut ruo rub rlt rlo rlb f Optical axis Lp Lh 2g Focal plane detector E=2-30 keV, f=4m Primary Secondary It is very important to increase sensitivity in this energy band Lp Segmented and highly nested conical approximation to a Wolter I geometry Depth-graded multilayers for XTP Design of depth-graded multilayers Key parameters X-ray rut ruo rub rlt rlo Emax=30 keV f Optical axis Lp Lh 2g Primary Lp rlb Secondary Focal plane detector f =4m Bilayer thickness = 2.5 nm Bragg Law: 2dsin = Depth-graded multilayers for XTP Design of depth-graded multilayers Merit functions Keys of design Optimized algorithms Starting structures Merit functions: m M F [ R s ( j ) R 0 ]2 j 1 Rs(j): reflectivity of each photon energy point R0 : reflectivity target value Depth-graded multilayers for XTP Design of depth-graded multilayers Optimized algorithms 1 simulated annealing algorithm SA is a global optimization algorithm However, slow convergence and long calculation time Some modifications a) Using more sophisticated new solution generation mechanism How to determine the new multilayer structure b) Annealing schedule in an optimized layer-thickness range How to optimize: which way The good results can be obtained in short time Depth-graded multilayers for XTP Design of depth-graded multilayers Optimized algorithms 2 Random search method Thickness of each layer: random change Some good results: long time 3 Local optimized algorithms Short time, sometimes good results Design results: starting structures Depth-graded multilayers for XTP Design of depth-graded multilayers Starting structures 1 Power law progression of bilayer thicknesses 2 Multilayer stacks with a varieties of periods Depth-graded multilayers for XTP Design of depth-graded multilayers Table. Design parameters of XTP Focal length 4m Outer Diameter 170 mm Inner Diameter 60 mm Mirror length 20 cm Mirror thickness Number of nested shells Energy range: 2-30 keV 0.2 mm 62 Depth-graded multilayers for XTP Design of depth-graded multilayers Number of groups Grazing incident angles 2 groups 0.20°, 0.30° 4 groups 0.15°, 0.20°, 0.25°, 0.30° 6 groups 0.15°, 0.18°, 0.21°, 0.24°, 0.27°, 0.30° 8 groups 0.15°, 0.17°, 0.19°, 0.21°, 0.23°, 0.25°, 0.27°, 0.30° 10 groups 0.15°, 0.16°, 0.17°, 0.18°, 0.20°, 0.22°, 0.24°, 0.26°, 0.28°, 0.30° 12 groups 0.15°, 0.16°, 0.17°, 0.18°, 0.19°, 0.20°, 0.21°, 0.22°, 0.24°, 0.26°, 0.28°, 0.30° 14 groups 0.15°, 0.16°, 0.17°, 0.18°, 0.19°, 0.20°, 0.21°, 0.22°, 0.23°, 0.24°, 0.25°, 0.26°, 0.28°, 0.30° 16 groups 0.15°, 0.16°, 0.17°, 0.18°, 0.19°, 0.20°, 0.21°, 0.22°, 0.23°, 0.24°, 0.25°, 0.26°, 0.27°, 0.28°, 0.29°, 0.30° Depth-graded multilayers for XTP Design of depth-graded multilayers Depth-graded multilayers for XTP Design of depth-graded multilayers Depth-graded multilayers for XTP Fabrication of supermirrors Magnetron Sputtering systems X-ray Timing and Polarization(XTP) project There are mainly two ways to build highly segmented nested optics The main process for making depth-graded multilayers is different between NuSTAR and Astro-H The depth-graded multilayers used in NuSTAR were deposited on slumped glass shells The depth-graded multilayers used in Astro-H were deposited on cylindrical glass mandrels X-ray Timing and Polarization(XTP) project New Magnetron Sputtering Coater Deposition on slumped glass shells on cylindrical glass mandrels Depth-graded multilayers for XTP XE-100 atomic force microscope D1 X-ray diffractometer made by Bede Company X-ray reflectometer in SR Depth-graded multilayers for XTP Depth-graded multilayers for XTP Comparison of different designs Depth-graded multilayers for XTP Correction of the deposition rate Depth-graded multilayers for XTP Schematic of replication of a multilayer Depth-graded multilayers for XTP The reflectivity of a multilayer after replication The reflectivity of a multilayer before replication Depth-graded multilayers for XTP Primary results about performance of depth-graded multilayers with power law progression of bilayer thicknesses W/Si multilayer Thickness distribution Grazing angle =0.3degrees Depth-graded multilayers for XTP Primary results about performance of depth-graded multilayers with power law progression of bilayer thicknesses W/Si multilayer Thickness distribution Grazing angle =0.35degrees Depth-graded multilayers for XTP Primary results about performance of depth-graded multilayers with power law progression of bilayer thicknesses W/Si multilayer Thickness distribution Grazing angle =0.4degrees Summary and outlook The LAMP and XTP multilayer mirrors have been designed and primarily fabricated. The primary experimental results were obtained Improving the performance of mirrors and making prototype for LAMP Improving the performance of mirrors and making prototype of a telescope for XTP Acknowledgements • IPOE multilayer group, Tongji University, China • BSRF Soft X-ray Group,China (M.Q.Cui, L.J.Sun, J. Zhu) • NSRL Spectral Radiation Standard and Metrology (H.J.Zhou) Strategic Priority Research Program on Space Science, the Chinese Academy of Sciences Natural Science Foundation of China National 863 High Technology Program