SIMBOLX OPTICS SIMBOLX Giovanni Pareschi INAF Osservatorio Astronomico
SIMBOL-X OPTICS SIMBOL-X Giovanni Pareschi INAF - Osservatorio Astronomico di Brera Upper Spider Case Shell Lower Spider “The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X Poster presentation related to the SX optics implementation • Basso et al. , “The relation between the weight and the quality image in a X-ray telescope, with a particular regard to Simbol-X” • Vernani, et al. , “Feasibility study for the manufacturing of the multilayer x-ray optics for Simbol-X” • Cotroneo et al, “Simbol-X mirror module design scientific optimization” • Basso et al, “The problem of the calibration of SIMBOL-X X-ray telescope” • Spiga et al. , “ The scattering caused by microrougnhess in the Simbol-X multilayer coated optics” • Romaine, et al, ”Multilayer coated hard X-ray mirrors based on Ni electroformed mirror shells” “The SIMBOL-X optics”, Bologna, 14 May 2007
OUTLINE SIMBOL-X • Designing of the Simbol-X optics • The technology for the optics fabrication • Remarks on the calibration issue “The SIMBOL-X optics”, Bologna, 14 May 2007
Top-level scientific requirements SIMBOL-X Energy band: ~0. 5 – ≥ 80 ke. V Field of view (at 30 ke. V): ≥ 12’ (diameter) On-axis effective area: ≥ 100 cm 2 ≥ 1000 cm 2 ≥ 600 cm 2 ≥ 300 cm 2 ≥ 100 cm 2 ≥ 50 cm 2 Detectors background < 2 10 -4 cts s-1 cm-2 ke. V-1 HED < 3 10 -4 cts s-1 cm-2 ke. V-1 LED On-axis sensitivity ≤ 10 -14 c. g. s. (~0. 5 µCrab), 10 -40 ke. V band, 3 s, 1 Ms, Line sensitivity at 68 ke. V < 3 10 -7 ph cm-2 s-1 (3 s, 1 Ms) Angular resolution ≤ 20”(HPD), E < 30 ke. V ≤ 40”(HPD) @ E = 60 ke. V (goal) Spectral resolution E/ E = 40 -50 at 6 -10 ke. V E/ E = 50 at 68 ke. V (goal) Absolute timing accuracy 100 µs (50 µs goal) Absolute pointing reconstruction ~ 3 (radius, 90%) (2” goal) Mission duration 3 years including commissioning and calibrations (2 years of scientific program) + provision for a possible 2 year extension Total number of pointings “The SIMBOL-X optics”, Bologna, 14 May 2007 at 0. 5 ke. V at 2 ke. V at 8 ke. V at 30 ke. V at 70 ke. V at 80 ke. V (goal) > 1000 (first 3 years, nominal mission) 500 (during the possible 2 year mission extension)
SX Flux Sensitivity SIMBOL-X “The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X Advantages of focusing optics versus direct-view detectors HEW = Half Energy Width = circle where 50 % of focused photons is contained r. HEW = FL * HEW [rad] Moreover: much better imaging capabilities! B =background flux, Tint = integration time, DE = integration bandwidth “The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X Angular resolution for past & future Hard X-ray Experiments Experiment Year “Imaging” technique SAX-PDS 1996 Rocking collimator INTEGRAL-IBIS 2002 Coded mask 720 arcsec (mask pitch) HEFT (baloon) 2005 Multilayer optics > 90 arcsec HEW NEXT 2013? Multilayer Optics 90 -60 arcsec HEW SIMBOL-X 2013? Multilayer Optics 15 -20 arcsec HEW “The SIMBOL-X optics”, Bologna, 14 May 2007 Angular resolution > 3600 arcsec (collimator pitch)
IMAGING (I) SIMBOL-X Osservazione XMM dello stesso campo tra 0. 1 e 10 ke. V “The SIMBOL-X optics”, Bologna, 14 May 2007
IMAGING (II) SIMBOL-X 10’ 50” HPD; eq. 2 Crab 10’ 1’ 10’ 30”HPD Eq. 2 Crab 15”HPD Eq. 0. 2 Crab “The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X The focusing problem in the hard X-ray region (> 10 ke. V) Wolter I geometry Aeff F 2 x qc 2 x R 2 At photon energies > 10 ke. V the cut-off angles R = reflectivity for total reflection are very small also for heavy L = mirror height q = incidence angle metals F = focal length the geometrical areas with usual focal lengths (> 10 m) are in general negligible but “The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X Focal Length Vs. Diameters for SIMBOL-X and other X-ray telescopes Multilayers 0. 6 o he s! t s pe r e ff co o s e e r l u t L te c e it g F h rc lon a t t h n g e li em F l n p o ti im a o rm ty t o i F n e u Th port op “The SIMBOL-X optics”, Bologna, 14 May 2007 Aeff F 2 x qc 2 x R 2
Design Constraints SIMBOL-X • FOCAL LENGTH: ≥ 19 m (due to formation flight parameters) • DETECTOR SIZE: 7 +/1 cm (Size of the LED wafer + lateral ditering) • NUMBER OF MIRROR SHELLS: ≤ 100 • MAXIMUM DIAMETER: 70 cm (i. e. as XMM) • MINIMUM DIAMETER: ≥ 25 cm (to allow the multilayer deposition “post facto”) • MASS TO AREA RATIO: a reliable number in line with angular resolution of at least 20 arcsec HEW • MASS: not larger than 480 (TBD) including structure “The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X Baseline Design SIMBOL-X Baseline detector size “The SIMBOL-X optics”, Bologna, 14 May 2007
Optics design SIMBOL-X • Heritage from XMM–Newton : nickel shells obtained by electroforming replication method; low mass obtained via a reduced thickness of shells • Coating : multi-layer Pt/C needed for requirement on large FOV and on sensitivity up to > 80 ke. V Focal length : 20 m Shell diameters : 30 to 70 cm Shell thickness : 0. 2 to 0. 6 mm Number of shells : 100 N. B. I: The optics module will have both sides covered with thermal blankets N. B. II: a proton diverter will be implemented “The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X Mirror shell production by Ni electroforming replication Beppo. SAX ESA credits Jet-X/Swift XMM-Newton “The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X Existing Coating Facilities at INAFOAB & Media Lario Techn. “The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X Thickness Vs. Diameter trend for Nireplicated optics HPD = 15 arcsec Year: 1994 Thin JET-X shell : 25 arcsec “The SIMBOL-X optics”, Bologna, 14 May 2007 HPD = 15 arcsec Year: 1999
Wall thickness/diameter trade-off F SIMBOL-X D w R A M/Acol Radial force for a thin shell. Exponent ‘z’=3 Edge moment for a thin shell. Exponent ‘z’=1 S M/Acol XMM computed f=7. 5 rescaling to the m correct focal length (20 m) 12” B Jet. X 1 shell f=3. 5 m HEW 25” Mass including structure ≈480 kg “The SIMBOL-X optics”, Bologna, 14 May 2007 Thicknesses ~ 2 times less than XMM
SIMBOL-X The use of stiffening rings for handling and integration of thin mirror shells Upper Spider Case Section of the ring Shell Lower Spider “The SIMBOL-X optics”, Bologna, 14 May 2007
Integration procedure SIMBOL-X Double grooves clips (DGC) Temporary spider Internal shaft (IS) Temporary spider must give stiffness to the upper side of the entire set of shells and must be removed after gluing of all the shells on the upper spider. DGC IS . . . Gluing of first set of DGC. Temporary IS can be used to apply control devises Removing of stiffening rings Positioning of second shell and gluing of second set of DGC Repeated for N shell “The SIMBOL-X optics”, Bologna, 14 May 2007 Gluing of N shells on the upper spider and removing all DGC Removing temporary IS
Multilayer deposition system SIMBOL-X C Pt Deposition of the multilayer film onto the internal surface of a replicated mirror shell (development activity carried out so far in collaboration with the Harvard-Smithsonian Cf. A) particularly well suited for Simbol-X, since based on large diameter optics “The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X Multilayer coated Ni mirror shells tested at Panter CREDITS: Panter/MPE “The SIMBOL-X optics”, Bologna, 14 May 2007
The long focal length calibration issue SIMBOL-X Simbol-X position * Possible Simbol-X position in the Panter facility for calibrations Fraction of the measured EA in double reflection for different lengths of the X-ray facility (as sourcedetector distance) for Simbol-X. The PANTER facility case corresponds approximately to the red line case. “The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X Test of very long focal length optics (20 - 30 m) in pencil beam setup with more than 1 shell Horizontal rotation correction Axial spin Comparators used to monitor the optic position during the optic spinning WM Vertical tilt correction FM Lateral correction Scheme of the manipulator: the possible movements/adjustments of the optical module are indicated “The SIMBOL-X optics”, Bologna, 14 May 2007
Programmatic points SIMBOL-X • By the end of the Phase a is planned to develope and calibrate a couple of multi-shell prototypes, caled down of a factor 2 wrt Simbol. X (Focal Length = 10 m, max diameter = 35 cm) • It is planned the development of a diamond-turning facility for the madrel fabrication • In Phase B a fully representative demonstrator will be developed and calibrated “The SIMBOL-X optics”, Bologna, 14 May 2007
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