XEUS mirror calibration: The PANTER X-ray Test Facility: accommodation of optics with long focal lengths etc., Wolfgang Burkert, Gisela Hartner, Bernd Budau XEUS Workshop, ESA, ESTEC, Noordwijk, 05-06 March 2008 1
Image section: the last 30 m XEUS Workshop, ESA, ESTEC, Noordwijk, 05-06 March 2008 2
Image section: the last 12 m XEUS Workshop, ESA, ESTEC, Noordwijk, 05-06 March 2008 3
Silicon pore optics elements standard silicon wafer, 6.5 cm size etching, ribs + membranes (0.17 mm) remaining pores: pitch 1.0 mm horizontal, 0.775 mm vertical plates stacked on top of each other HPO (High-resolution Pore Optics) 2 HPOs combined via bracket XOU (X-ray Optical Unit): one HPO-P and one HPO-H (Wolter-I approximation) can be mounted into a petal (e.g. 1/16 of full ring) (formally) focal length of 50 m XEUS Workshop, ESA, ESTEC, Noordwijk, 05-06 March 2008 4
PANTER: XOU-1 2 HPOs combined via bracket XOU XEUS Workshop, ESA, ESTEC, Noordwijk, 05-06 March 2008 5
HPO-105-uc: EPIC-pn slit mask measurements: pores PN: mandrel at top, unclamped, slit centered on open pore area XEUS Workshop, ESA, ESTEC, Noordwijk, 05-06 March 2008 6
HPO-105-uc: EPIC-pn slit mask measurements: plates PN: mandrel at top, unclamped, slit centered on plate front side, illumination: exit part of plate n and entry part of plate n + 1 XEUS Workshop, ESA, ESTEC, Noordwijk, 05-06 March 2008 7
PANTER: Petal with XOU-2 and XOU-3 XEUS Workshop, ESA, ESTEC, Noordwijk, 05-06 March 2008 8
Petal: schematic and real XEUS Workshop, ESA, ESTEC, Noordwijk, 05-06 March 2008 9
Petal: XOU-2 and XOU-3 alignment slit mask, plate 1.5, height difference can be explained by petal rotation center XEUS Workshop, ESA, ESTEC, Noordwijk, 05-06 March 2008 10
Thin lens equation: focal image location at PANTER 1 g + 1 b = 1 f b = f g g f Example: g = 123.6 m (8 m in front of detector plane) f = 20 m b = 23.86 m f = 35 m b = 48.8 m f = 50 m b = 84 m g = l b b = l ( 2 1 1 4f ) l (l > 4f) Example: l = 131.6 m (current distance detector plane X-ray source) f = 20 m b = 24.60 m f = 35 m b = n.a. XEUS Workshop, ESA, ESTEC, Noordwijk, 05-06 March 2008 11
PANTER: XOU-4 plate distances single HPO-H (left) and double (right) reflections determine distance of plates and derive focusing efficiency XEUS Workshop, ESA, ESTEC, Noordwijk, 05-06 March 2008 12
XOU-4: wedged plates and focusing focal length f adjusted via kink angle β = 1 2 arctan(r/f): f = r/ tan(2β). error in HPO alignment of XOU: deviation from nominal value β 0 = 1 2 arctan(r/f 0) similarly for uncertainties in king angle measurement finite source distance (g = 123.6 m) moves image location further away reduces the focusing effect ( focused image size x) at measurement distance of d = 8.0 m thin lens equation 1/g + 1/b = 1/f x = 1 d/b = 1 d/f (g f)/g XEUS Workshop, ESA, ESTEC, Noordwijk, 05-06 March 2008 13
XOU-4: wedged plates and focusing: plate distance geometric plate distance (pitch): 775 µm measured plate distance: 713 µm expected plate distance from kink angle with parallel beam: d = 8 m, d/b p: 661.3 µm expected plate distance from kink angle with divergent beam: 711.5 µm measured plate distance consistent with reduced focusing (within measurement accuracy) confirmed/explained by BESSY/PANTER measurements of kink angle and divergent beam set-up XEUS Workshop, ESA, ESTEC, Noordwijk, 05-06 March 2008 14
Achieved/ongoing improvements at PANTER new dedicated CCD camera for PANTER ( TRoPIC) 1 frame store CCD (erosita, 19.2 19.2 mm 2 FOV) smaller pixel size: 75 µm sub-pixel resolution! thicker wafer: 450 µm QE at high energies graded shield, low background improved low-energy resolution energy band pass: 0.1 120 kev (even more flexible) erosita: 384 384 pixels (28.8 28.8 mm 2 FOV): spare model will take TRoPIC s role later (replacement, addition) extend range along optical axis: focus search (focal depth), out-of-focus imaging XEUS Workshop, ESA, ESTEC, Noordwijk, 05-06 March 2008 15
PANTER: parallel beam (CDS) preparing parallel beam set-up (CDS telescope as condensor) invert set-up with X-ray source in chamber XEUS Workshop, ESA, ESTEC, Noordwijk, 05-06 March 2008 16
PANTER: main building XEUS Workshop, ESA, ESTEC, Noordwijk, 05-06 March 2008 17
PANTER: 25 m from detector plane XEUS Workshop, ESA, ESTEC, Noordwijk, 05-06 March 2008 18
PANTER: optics locations XEUS Workshop, ESA, ESTEC, Noordwijk, 05-06 March 2008 19
Upgrade of PANTER: other calibration campaigns main constraint: erosita readiness (2011): Spektr-X-G launch date must not be influenced: facility shall not be broken too long by upgrades erosita FM (2009/10): cleanliness requirements also for other items at PANTER perform facility upgrade 2008/09 Options at PANTER: upgrade in future build another chamber (+ clean room) at about 20 25 m from focal plane instrumentation: this could accommodate translation/rotation stages and corresponding optics (of long focal lengths) significant changes to facility layout: new building XEUS Workshop, ESA, ESTEC, Noordwijk, 05-06 March 2008 20
PANTER: main building: grey area XEUS Workshop, ESA, ESTEC, Noordwijk, 05-06 March 2008 21
Options at PANTER: upgrade in future build another chamber (+ clean room + pumps etc.) as extension to current chamber: removable tube (50 cm diameter) to new chamber, flange already present at door of chamber, erosita/tropic detector in new chamber, could also be used for an end-to-end test (SIMBOL-X) mount optics in current chamber at 8m position. less significant changes in facility layout Options at PANTER: upgrade in future similar to previous idea, but extend complete chamber (3.5 m), entrance at side XEUS Workshop, ESA, ESTEC, Noordwijk, 05-06 March 2008 22
Summary and Conclusions Silicon pore optics have been successfully measured and analysed at PANTER Wedged plates do focus consistent with expectations Focal plane instrumentation well-suited, covers wide range of observational parameters: large FOV, high count rates, low background, energy resolution and band pass, etc. prepare for future missions: erosita, SIMBOL-X, XEUS: parallel beam, chamber,... XEUS Workshop, ESA, ESTEC, Noordwijk, 05-06 March 2008 23