X-ray imaging of synchrotrons & lab sources. Janos Kirz

Transcription

1 X-ray imaging of synchrotrons & lab sources Janos Kirz EuXFEL 11/2017

2 W. C. Röntgen 1895 Origins Nov 8 first observation Nov 9 Dec 27 experimentation, write-up Dec 28 manuscript submitted Sitzungsberichte der Physikalischen-medizinischen Gesellschaft zu Würzburg See bones in hand shadowgraphs Instant sensation around the world Radiology absorption contrast Works well for bone fracture air vs fluid in lung tooth decay

3 3D Imaging: CAT scans 3D imaging based on many projections 1979 Nobel prize Godfrey Hounsfield & Allan McLeod Cormack Resolution: several mm Limitations: breathing, beating heart, digestion,

4 Better radiology? Hundreds of images: high radiation dose! Absorption contrast in soft tissue poor To reduce dose improve contrast! Extract phase shift from interference pattern Bonse-Hart interferometer Appl. Phys. Lett 6, 155 (1965) Phase contrast tomography A. Momose et al. Nature Med. 2, 473 (1996)

5 Interferometry without crystals Grating-based phase measurement Using Talbot (1836) effect (self-image) A. Momose et al. Jpn. J Appl. Phy. 42, L866 (2003) Spring-8 source for coherence Object distorts Moire pattern Talbot-Lau interferometer Third grating for use with ordinary X-ray tube F. Pfeiffer et al. Nature Phys. 2, 258 (2006) Intensive development worldwide

6 Absorption & Phase contrast F. Pfeiffer et al. Nature Phys. 2, 258 (2006)

7 Application to mammography Phase contrast Absorption contrast (From Konica Minolta)

8 X-ray micro-tomography-als Lots of Math

9 Microtomography Simple projection onto detector Resolution: ~ 1-5 µm Commercial microscopes Lab sources or synchrotrons Zeiss (formerly XRADIA) Brucker (formerly Skyscan) 3D Studies of bone structure, seeds, small animals

10 Examples of Grapevine Xylem

11 Get insights in insect flight control Investigate the biomechanics underlying flight manoeuvres and gaze shifts à CT following the dynamics of 100+ Hz wing beat! Need: single-shot propagation-based phase contrast high-speed X-ray tomographic microscopy SLS beam Requires: Coherence and Flux BRIGHTNESS So, this is a perfect task for a synchrotron! S. M. Walker et al. P{LOS Biology 12, e (2014) 11

12 Toward higher resolution Microscopes with zone plate optics Resolution ~ 20 nm (50 nm in 3D) Radiation damage becomes limitation! Cryo preserves morphology Instruments at BESSY II ALS ALBA

13 Cryo Soft X-ray Tomography of Cells at the MISTRAL beamline E. Pereiro et al. J. Synchr. Rad. 16, (2009) reconstructed slice 1 µm A. SorrenBno et al. J. Synchr. Rad. 22, (2015)

14 The ultimate challenge Radiation damage in biological samples Frozen hydrated state of protein Howells et al. JESRP 170, 4 (2009) Resolution limit? Inverse fourth power law of dose vs resolution: Dose ~ 1/resolution-size 4

15 Scanning X-ray diffracbon microscopy Ptychography with a focused X-ray probe J. Rodenburg Pilatus 2M Reconstruct bith amplitude and phase P. Thibault, M. Dierolf, A. Menzel, O. Bunk, C. David, F. Pfeiffer, Science, 321, (2008). 15

16 Frozen hydrated unstained brain tissue Locate, extract and further study intact hallmarks of Parkinson disease Large volumes High resolubon As close to nabve state as possible (no staining) Sarah Shamoradian Quickly biopsy-punched, infiltrated with cryo protectant, mounted on pin and gradually frozen Trimmed with cryo ultramicrotome Cryo transferred to OMNY ~ 80 micron at the base, ~ 100 nm 3D resolubon 446 projecbons 17 hour measurement Shamoradian et al., Sci. Rep (2017) Page 16

17 3D Elemental mapping by XRF 3D scan as for tomography Record fluorescence spectrum for each point Perform tomographic recontstruction for each element

18 3D elemental microtomography of Cyclotella meneghiana M. de Jonge, et al., PNAS 107, 15676, (2010)

19 Changing Landscape of X-ray facilities ~ dedicated storage rings 30+ years: a revolution in X-ray analysis ~ 2010 Toward higher brightness, coherence MBA lattice, MAX IV, Sirius, storage ring upgrades FELs LCLS, FLASH, FERMI, SACLA, EuXFEL, Older sources: DORIS, NSLS, Daresbury, shut down Fewer stations available for routine measurements

20 New initiatives in Lab-scale sources to fill the gap EXCILLUM liquid metal jet Lyncean back-scattered Compton Sigray microstructured anode in diamond substrate

21 Conclusions I X-rays are great! Penetrate opaque objects Rich spectra allow elemental & chemical info Radiation damage is a concern One way to mitigate radiation damage: cryo Other ways: many copies, as in crystals or diffract & destroy... but ptychography not compatible

22 Conclusions II A bit of humility: There is competition! MRI for imaging humans Cryo EM for high resolution on thin samples Super resolution visible light microscopy

23 Acknowledgments Thanks to colleages who provided material for this talk: Manuel Guizar Sicarios Eva Pereiro Marco Stampanoni Andrew McElrone

24 Thank you