XEUS mirror calibration:

Transcription

1 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, March

2 Image section: the last 30 m XEUS Workshop, ESA, ESTEC, Noordwijk, March

3 Image section: the last 12 m XEUS Workshop, ESA, ESTEC, Noordwijk, March

4 Silicon pore optics elements standard silicon wafer, 6.5 cm size etching, ribs + membranes (0.17 mm) remaining pores: pitch 1.0 mm horizontal, 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, March

5 PANTER: XOU-1 2 HPOs combined via bracket XOU XEUS Workshop, ESA, ESTEC, Noordwijk, March

6 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, March

7 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, March

8 PANTER: Petal with XOU-2 and XOU-3 XEUS Workshop, ESA, ESTEC, Noordwijk, March

9 Petal: schematic and real XEUS Workshop, ESA, ESTEC, Noordwijk, March

10 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, March

11 Thin lens equation: focal image location at PANTER 1 g + 1 b = 1 f b = f g g f Example: g = m (8 m in front of detector plane) f = 20 m b = m f = 35 m b = 48.8 m f = 50 m b = 84 m g = l b b = l ( f ) l (l > 4f) Example: l = m (current distance detector plane X-ray source) f = 20 m b = m f = 35 m b = n.a. XEUS Workshop, ESA, ESTEC, Noordwijk, March

12 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, March

13 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 = 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, March

14 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: µm expected plate distance from kink angle with divergent beam: 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, March

15 Achieved/ongoing improvements at PANTER new dedicated CCD camera for PANTER ( TRoPIC) 1 frame store CCD (erosita, 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: kev (even more flexible) erosita: pixels ( 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, March

16 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, March

17 PANTER: main building XEUS Workshop, ESA, ESTEC, Noordwijk, March

18 PANTER: 25 m from detector plane XEUS Workshop, ESA, ESTEC, Noordwijk, March

19 PANTER: optics locations XEUS Workshop, ESA, ESTEC, Noordwijk, March

20 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 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, March

21 PANTER: main building: grey area XEUS Workshop, ESA, ESTEC, Noordwijk, March

22 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, March

23 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, March

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