Hagemann, Johannes

[["dc.bibliographiccitation.artnumber","3468"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Nature Communications"],["dc.bibliographiccitation.volume","12"],["dc.contributor.author","Vaßholz, Malte"],["dc.contributor.author","Hoeppe, H. P."],["dc.contributor.author","Hagemann, Johannes"],["dc.contributor.author","Rosselló, J. M."],["dc.contributor.author","Osterhoff, Markus"],["dc.contributor.author","Mettin, Robert"],["dc.contributor.author","Kurz, Thomas"],["dc.contributor.author","Schropp, A."],["dc.contributor.author","Seiboth, F."],["dc.contributor.author","Schroer, C. G."],["dc.contributor.author","Scholz, M."],["dc.contributor.author","Möller, J."],["dc.contributor.author","Hallmann, J."],["dc.contributor.author","Boesenberg, U."],["dc.contributor.author","Kim, C."],["dc.contributor.author","Zozulya, A."],["dc.contributor.author","Lu, W."],["dc.contributor.author","Shayduk, R."],["dc.contributor.author","Schaffer, R."],["dc.contributor.author","Madsen, A."],["dc.contributor.author","Salditt, Tim"],["dc.date.accessioned","2021-06-08T12:44:14Z"],["dc.date.available","2021-06-08T12:44:14Z"],["dc.date.issued","2021-06-08"],["dc.description.abstract","Cavitation bubbles can be seeded from a plasma following optical breakdown, by focusing an intense laser in water. The fast dynamics are associated with extreme states of gas and liquid, especially in the nascent state. This offers a unique setting to probe water and water vapor far-from equilibrium. However, current optical techniques cannot quantify these early states due to contrast and resolution limitations. X-ray holography with single X-ray free-electron laser pulses has now enabled a quasi-instantaneous high resolution structural probe with contrast proportional to the electron density of the object. In this work, we demonstrate cone-beam holographic flash imaging of laser-induced cavitation bubbles in water with nanofocused X-ray free-electron laser pulses. We quantify the spatial and temporal pressure distribution of the shockwave surrounding the expanding cavitation bubble at time delays shortly after seeding and compare the results to numerical simulations."],["dc.description.sponsorship","Open-Access-Publikationsfonds 2021"],["dc.identifier.doi","10.1038/s41467-021-23664-1"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/87172"],["dc.relation.issn","2041-1723"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.rights","CC BY 4.0"],["dc.subject.gro","x-ray imaging"],["dc.title","Pump-probe X-ray holographic imaging of laser-induced cavitation bubbles with femtosecond FEL pulses"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","52"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Journal of Synchrotron Radiation"],["dc.bibliographiccitation.lastpage","63"],["dc.bibliographiccitation.volume","28"],["dc.contributor.author","Hagemann, Johannes"],["dc.contributor.author","Vaßholz, Malte"],["dc.contributor.author","Hoeppe, Hannes"],["dc.contributor.author","Osterhoff, Markus"],["dc.contributor.author","Rosselló, Juan M."],["dc.contributor.author","Mettin, Robert"],["dc.contributor.author","Seiboth, Frank"],["dc.contributor.author","Schropp, Andreas"],["dc.contributor.author","Möller, Johannes"],["dc.contributor.author","Hallmann, Jörg"],["dc.contributor.author","Kim, Chan"],["dc.contributor.author","Scholz, Markus"],["dc.contributor.author","Boesenberg, Ulrike"],["dc.contributor.author","Schaffer, Robert"],["dc.contributor.author","Zozulya, Alexey"],["dc.contributor.author","Lu, Wei"],["dc.contributor.author","Shayduk, Roman"],["dc.contributor.author","Madsen, Anders"],["dc.contributor.author","Schroer, Christian G."],["dc.contributor.author","Salditt, Tim"],["dc.date.accessioned","2021-04-14T08:30:07Z"],["dc.date.available","2021-04-14T08:30:07Z"],["dc.date.issued","2021"],["dc.description.abstract","X-ray free-electron lasers (XFELs) have opened up unprecedented opportunities\r\nfor time-resolved nano-scale imaging with X-rays. Near-field propagationbased\r\nimaging, and in particular near-field holography (NFH) in its highresolution\r\nimplementation in cone-beam geometry, can offer full-field views of a\r\nspecimen’s dynamics captured by single XFEL pulses. To exploit this capability,\r\nfor example in optical-pump/X-ray-probe imaging schemes, the stochastic\r\nnature of the self-amplified spontaneous emission pulses, i.e. the dynamics of the\r\nbeam itself, presents a major challenge. In this work, a concept is presented to\r\naddress the fluctuating illumination wavefronts by sampling the configuration\r\nspace of SASE pulses before an actual recording, followed by a principal\r\ncomponent analysis. This scheme is implemented at the MID (Materials Imaging\r\nand Dynamics) instrument of the European XFEL and time-resolved NFH\r\nis performed using aberration-corrected nano-focusing compound refractive\r\nlenses. Specifically, the dynamics of a micro-fluidic water-jet, which is commonly\r\nused as sample delivery system at XFELs, is imaged. The jet exhibits rich\r\ndynamics of droplet formation in the break-up regime. Moreover, pump–probe\r\nimaging is demonstrated using an infrared pulsed laser to induce cavitation and\r\nexplosion of the jet."],["dc.identifier.doi","10.1107/S160057752001557X"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/83114"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-399"],["dc.relation.eissn","1600-5775"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.rights","CC BY 4.0"],["dc.subject.gro","x-ray imaging"],["dc.title","Single-pulse phase-contrast imaging at free-electron lasers in the hard X-ray regime"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","987-994"],["dc.bibliographiccitation.issue","3"],["dc.bibliographiccitation.journal","Journal of Synchrotron Radiation"],["dc.bibliographiccitation.volume","28"],["dc.contributor.author","Osterhoff, Markus"],["dc.contributor.author","Vaßholz, Malte"],["dc.contributor.author","Hoeppe, Hannes Paul"],["dc.contributor.author","Rosselló, Juan Manuel"],["dc.contributor.author","Mettin, Robert"],["dc.contributor.author","Hagemann, Johannes"],["dc.contributor.author","Möller, Johannes"],["dc.contributor.author","Hallmann, Jörg"],["dc.contributor.author","Scholz, Markus"],["dc.contributor.author","Schaffer, Robert"],["dc.contributor.author","Boesenberg, Ulrike"],["dc.contributor.author","Kim, Chan"],["dc.contributor.author","Zozulya, Alexey"],["dc.contributor.author","Lu, Wei"],["dc.contributor.author","Shayduk, Roman"],["dc.contributor.author","Madsen, Anders"],["dc.contributor.author","Salditt, Tim"],["dc.date.accessioned","2021-05-07T07:22:19Z"],["dc.date.available","2021-05-07T07:22:19Z"],["dc.date.issued","2021-05-01"],["dc.description.abstract","Single-pulse holographic imaging at XFEL sources with 1012 photons delivered in pulses shorter than 100 fs reveal new quantitative insights into fast phenomena. Here, a timing and synchronization scheme for stroboscopic imaging and quantitative analysis of fast phenomena on time scales (sub-ns) and length-scales (≲100 nm) inaccessible by visible light is reported. A fully electronic delay-and-trigger system has been implemented at the MID station at the European XFEL, and applied to the study of emerging laser-driven cavitation bubbles in water. Synchronization and timing precision have been characterized to be better than 1 ns."],["dc.identifier.doi","10.1107/S1600577521003052"],["dc.identifier.pmid","33950007"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/84669"],["dc.language.iso","en"],["dc.relation.eissn","1600-5775"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.rights","CC BY 4.0"],["dc.subject.gro","x-ray imaging"],["dc.title","Nanosecond timing and synchronization scheme for holographic pump-probe studies at the MID instrument at European XFEL"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","498"],["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","Journal of Synchrotron Radiation"],["dc.bibliographiccitation.lastpage","505"],["dc.bibliographiccitation.volume","24"],["dc.contributor.author","Hagemann, Johannes"],["dc.contributor.author","Robisch, Anna-Lena"],["dc.contributor.author","Osterhoff, Markus"],["dc.contributor.author","Salditt, Tim"],["dc.date.accessioned","2020-11-05T15:05:24Z"],["dc.date.available","2020-11-05T15:05:24Z"],["dc.date.issued","2017"],["dc.description.abstract","In X-ray holographic near-field imaging the resolution and image quality depend sensitively on the beam. Artifacts are often encountered due to the strong focusing required to reach high resolution. Here, two schemes for reconstructing the complex-valued and extended wavefront of X-ray nano-probes, primarily in the planes relevant for imaging (i.e. focus, sample and detection plane), are presented and compared. Firstly, near-field ptychography is used, based on scanning a test pattern laterally as well as longitudinally along the optical axis. Secondly, any test pattern is dispensed of and the wavefront reconstructed only from data recorded for different longitudinal translations of the detector. For this purpose, an optimized multi-plane projection algorithm is presented, which can cope with the numerically very challenging setting of a divergent wavefront emanating from a hard X-ray nanoprobe. The results of both schemes are in very good agreement. The probe retrieval can be used as a tool for optics alignment, in particular at X-ray nanoprobe beamlines. Combining probe retrieval and object reconstruction is also shown to improve the image quality of holographic near-field imaging."],["dc.identifier.doi","10.1107/S160057751700128X"],["dc.identifier.gro","3142476"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/68459"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-352.6"],["dc.notes.status","final"],["dc.relation.eissn","1600-5775"],["dc.relation.issn","1600-5775"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.rights","CC BY 2.0"],["dc.subject.gro","x-ray imaging"],["dc.title","Probe reconstruction for holographic X-ray imaging"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","no"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","518"],["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","Journal of Synchrotron Radiation"],["dc.bibliographiccitation.lastpage","529"],["dc.bibliographiccitation.volume","28"],["dc.contributor.affiliation","Wittmeier, Andrew; 1Institute for X-Ray Physics, University of Göttingen, Friedrich-Hund-Platz 1, 37077Göttingen, Germany"],["dc.contributor.affiliation","Cassini, Chiara; 1Institute for X-Ray Physics, University of Göttingen, Friedrich-Hund-Platz 1, 37077Göttingen, Germany"],["dc.contributor.affiliation","Töpperwien, Mareike; 1Institute for X-Ray Physics, University of Göttingen, Friedrich-Hund-Platz 1, 37077Göttingen, Germany"],["dc.contributor.affiliation","Denz, Manuela; 1Institute for X-Ray Physics, University of Göttingen, Friedrich-Hund-Platz 1, 37077Göttingen, Germany"],["dc.contributor.affiliation","Hagemann, Johannes; 1Institute for X-Ray Physics, University of Göttingen, Friedrich-Hund-Platz 1, 37077Göttingen, Germany"],["dc.contributor.affiliation","Osterhoff, Markus; 1Institute for X-Ray Physics, University of Göttingen, Friedrich-Hund-Platz 1, 37077Göttingen, Germany"],["dc.contributor.affiliation","Salditt, Tim; 1Institute for X-Ray Physics, University of Göttingen, Friedrich-Hund-Platz 1, 37077Göttingen, Germany"],["dc.contributor.author","Wittmeier, Andrew"],["dc.contributor.author","Cassini, Chiara"],["dc.contributor.author","Töpperwien, Mareike"],["dc.contributor.author","Denz, Manuela"],["dc.contributor.author","Hagemann, Johannes"],["dc.contributor.author","Osterhoff, Markus"],["dc.contributor.author","Salditt, Tim"],["dc.contributor.author","Köster, Sarah"],["dc.date.accessioned","2021-04-14T08:28:23Z"],["dc.date.available","2021-04-14T08:28:23Z"],["dc.date.issued","2021"],["dc.date.updated","2022-02-09T13:21:31Z"],["dc.description.abstract","X‐rays are emerging as a complementary probe to visible‐light photons and electrons for imaging biological cells. By exploiting their small wavelength and high penetration depth, it is possible to image whole, intact cells and resolve subcellular structures at nanometer resolution. A variety of X‐ray methods for cell imaging have been devised for probing different properties of biological matter, opening up various opportunities for fully exploiting different views of the same sample. Here, a combined approach is employed to study cell nuclei of NIH‐3T3 fibroblasts. Scanning small‐angle X‐ray scattering is combined with X‐ray holography to quantify length scales, aggregation state, and projected electron and mass densities of the nuclear material. Only by joining all this information is it possible to spatially localize nucleoli, heterochromatin and euchromatin, and physically characterize them. It is thus shown that for complex biological systems, like the cell nucleus, combined imaging approaches are highly valuable."],["dc.description.abstract","The combination of small‐angle X‐ray scattering and X‐ray holography enables us to visualize and characterize biological material in cell nuclei spanning multiple length scales. image"],["dc.identifier.doi","10.1107/S1600577520016276"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/82591"],["dc.identifier.url","https://mbexc.uni-goettingen.de/literature/publications/218"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-399"],["dc.publisher","International Union of Crystallography"],["dc.relation","EXC 2067: Multiscale Bioimaging"],["dc.relation.eissn","1600-5775"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Köster (Cellular Biophysics)"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.rights","This is an open access article under the terms of the Creative Commons Attribution License, which permits use,\r\n distribution and reproduction in any medium, provided the original work is properly cited."],["dc.subject.gro","x-ray imaging"],["dc.subject.gro","x-ray scattering"],["dc.subject.gro","cellular biophysics"],["dc.title","Combined scanning small-angle X-ray scattering and holography probes multiple length scales in cell nuclei"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]