“the simbol-x optics”, bologna, 14 may 2007 simbol-x simbol-x optics simbol-x optics giovanni...
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“The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X SIMBOL-X OPTICSSIMBOL-X OPTICS
Giovanni PareschiINAF - Osservatorio Astronomico di Brera
Lower Spider
Upper Spider
Case
Shell
“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
SIMBOL-X
OUTLINEOUTLINE
• 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
SIMBOL-X
Top-level scientific requirementsTop-level scientific requirementsEnergy band: ~0.5 – ≥ 80 keV
Field of view (at 30 keV): ≥ 12’ (diameter)
On-axis effective area:
≥ 100 cm2 at 0.5 keV≥ 1000 cm2 at 2 keV≥ 600 cm2 at 8 keV≥ 300 cm2 at 30 keV≥ 100 cm2 at 70 keV≥ 50 cm2 at 80 keV (goal)
Detectors background< 210-4 cts s-1cm-2keV-1 HED< 310-4 cts s-1cm-2keV-1 LED
On-axis sensitivity ≤ 10-14c.g.s.(~0.5 µCrab), 10-40 keV band, 3 1Ms,
Line sensitivity at 68 keV < 3 10-7 ph cm-2 s-1 (3 1Ms)
Angular resolution≤ 20”(HPD), E < 30 keV≤ 40”(HPD) @ E = 60 keV (goal)
Spectral resolutionE/E = 40-50 at 6-10 keVE/E = 50 at 68 keV (goal)
Absolute timing accuracy 100 µs (50 µs goal)
Absolute pointing reconstruction ~ 3 (radius, 90%) (2” goal)
Mission duration3 years including commissioning and calibrations (2 years of scientific program) + provision for a possible 2 year extension
Total number of pointings> 1000 (first 3 years, nominal mission) 500 (during the possible 2 year mission extension)
“The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X
SX Flux Sensitivity
“The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X
Advantages of focusing optics versus Advantages of focusing optics versus direct-view detectorsdirect-view detectors
ETA
BnF
eff
int
min2
ETA
BnF
eff
HEWr
***5.0
**
int
min
Moreover: much better imaging capabilities!B =background flux, Tint = integration time, E = integration bandwidth
rHEW = FL * HEW [rad]
HEW = Half Energy Width = circle where 50 % of focused photons is contained
“The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X
Angular resolution for past & future Hard Angular resolution for past & future Hard X-ray ExperimentsX-ray Experiments
ExperimentExperiment YearYear ““Imaging” Imaging” techniquetechnique
Angular Angular resolutionresolution
SAX-PDS 1996 Rocking collimator
> 3600 arcsec(collimator pitch)
INTEGRAL-IBIS 2002 Coded mask 720 arcsec(mask pitch)
HEFT (baloon) 2005 Multilayer optics > 90 arcsec HEW
NEXT 2013? Multilayer Optics
90-60 arcsecHEW
SIMBOL-X 2013? Multilayer Optics
15-20 arcsecHEW
“The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X
IMAGING (I)IMAGING (I)
Osservazione XMM dello stesso campo tra 0.1 e 10 keV
“The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X
IMAGING (II)IMAGING (II)
1’
50” HPD; eq. 2Crab
30”HPDEq.2Crab
15”HPDEq.0.2Crab
10’
10’
10’
“The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X
The focusing problem in the hard X-ray The focusing problem in the hard X-ray region (> 10 keV)region (> 10 keV)
Ecrit
but
Wolter I geometry
F = focal length R = reflectivity
L = mirror height = incidence angle
Aeff F2 x c2 x R2
At photon energies > 10 keV the cut-off angles for total reflection are very small also for heavy metals
the geometrical areas with usual focal the geometrical areas with usual focal lengths (> 10 m) are in general lengths (> 10 m) are in general negligiblenegligible
“The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X
0.6 o
Focal Length Vs. Diameters for SIMBOL-X Focal Length Vs. Diameters for SIMBOL-X and other X-ray telescopes and other X-ray telescopes
Multilayers
Aeff F2 x c2 x R2
Ecrit
The Formatio
n Flight architecture offers th
e
The Formatio
n Flight architecture offers the
opportunity to im
plement long FL telescopes!
opportunity to
implement lo
ng FL telescopes!
“The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-XDesign ConstraintsDesign Constraints
• 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
SIMBOL-X Baseline DesignSIMBOL-X Baseline Design
Baseline
detector size
“The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X
Optics designOptics design
Focal length : 20 mShell diameters : 30 to 70 cmShell thickness : 0.2 to 0.6 mm Number of shells : 100
• 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 keV
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 Mirror shell production by Ni electroforming replicationreplication
BeppoSAX
Jet-X/Swift
XMM-Newton
ESA credits
“The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X
Existing Coating FacilitiesExisting Coating Facilities at INAF- at INAF-OAB & Media Lario Techn.OAB & Media Lario Techn.
“The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X
HPD = 15 arcsecYear: 1994 HPD = 15 arcsec
Year: 1999
Thin JET-X shell : 25 arcsec
Thickness Vs. Diameter trend for Ni-Thickness Vs. Diameter trend for Ni-replicated opticsreplicated optics
“The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X
Wall thickness/diameter trade-offWall thickness/diameter trade-off
z
kHHEW
1
A
B
XMM f=7.5m
JetX 1shell f=3.5m
S
M/Acol
computed rescaling to the correct focal length (20m)
HEW
M/Acol
12” 25”
z
d
tHEW
Mass including structure ≈480 kg
Radial force for a thin shell. Exponent ‘z’=3
R
w
F
3
3
tE
RFwHEW
tE
rMHEW 0
Edge moment for a thin shell. Exponent ‘z’=1
Thicknesses ~ 2 times less than XMM
“The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X
Lower Spider
Upper Spider
Case
ShellSection of the ring
The use of stiffening rings for handling The use of stiffening rings for handling and integration of thin mirror shellsand integration of thin mirror shells
“The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X
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.
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
ISDGC
. . . . .
Gluing of N shells on the upper spider and removing all DGC
Removing temporary IS
Temporary spiderDouble grooves clips (DGC)
Internal shaft (IS)
Integration procedureIntegration procedure
“The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X
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 CfA) particularly well suited for Simbol-X, since based on large diameter optics
Pt
C
Multilayer deposition systemMultilayer deposition system
“The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X
Multilayer coated Ni mirror shells Multilayer coated Ni mirror shells tested at Pantertested at Panter
CREDITS: Panter/MPE
“The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X
The long focal length calibration issueThe long focal length calibration issue
Possible Simbol-X position in the Panter facility for calibrations
*Simbol-X position
Fraction of the measured EA in double reflection for different lengths of the X-ray facility (as source-detector 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) Test of very long focal length optics (20 - 30 m) in pencil beam setup with more than 1 shellin pencil beam setup with more than 1 shell
Horizontal rotation correction
Lateral correction
FM
WM
Comparators used to monitor the optic position during the optic spinning
Vertical tilt correction
Axial spin
Scheme of the manipulator: the possible movements/adjustments of the optical module are indicated
“The SIMBOL-X optics”, Bologna, 14 May 2007
SIMBOL-X
Programmatic pointsProgrammatic points
• 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