1. Facility Talks
PETRA IV will be the synchrotron radiation source with the highest spectral brightness worldwide, reaching the diffraction limit up to X-ray energies of about 10 keV. In order to make full use of the significantly improved properties of the source, further development and improvement of beamline and experiment instrumentation is needed. In this respect, experiment developers and beamline designers will have to manage challenges like, e.g., the preservation of the high brightness and coherence of the source down to the sample, environmental and sample stability, ultra-precision mechanics and the large amount of data produced by the detectors.
The session will present and discuss concepts, ideas, and challenges of topics like X-ray mirrors, X-ray monochromators, Undulators, Nano-transfer and sample positioning, Fill pattern and timing, and Automation.
2. Pulse Structure and Timing
Pulsed synchrotron radiation sources are ideal facilities for performing time-resolved experiments as it was shown during the last years using pump-probe X-ray spectroscopy and diffraction, stroboscopic X-ray diffraction, X-ray photon correlation spectroscopy, nuclear resonance scattering, and time-of-flight spectroscopy of electrons and ions. Time-resolved studies emerge even more at free-electron lasers, like FLASH or European XFEL with femtosecond pulse width. Nevertheless, time-resolved experiments will be important techniques at the current and future storage-ring-based synchrotron radiation sources.
This session will be devoted to time-resolved techniques at the new PETRA IV storage ring and to the technical aspects related to such studies. In particular, this includes the time synchronization between synchrotron ring and beamline devices, the development of fast detectors, pulse-to-pulse stability, coherence properties of single pulses and other aspects of time resolved measurements. In addition, the new pulse structures which will be introduced to the PETRA IV storage ring in both timing and brightness modes will be discussed from the point of view of advantages and drawbacks for the particular techniques. The session aims at defining future routes for research employing the enhanced properties of the envisioned PETRA IV storage ring and PETRA III successor beam lines. Further ideas and discussions are welcome.
I. Sergeev, A. Kotlov, O. Leupold, M. Naumova, W. Roseker, A. Schökel, F. Trinter
3. Detector Requirements at PETRA IV
To take advantage of the extreme brilliance of PETRA IV, large improvements in detector technology are needed. For example, experiments currently performed at 100-1000 Hz rates could be performed at 10-100 kHz if sufficiently fast detectors become available, which would make it possible to obtain much better time resolution, scan large samples, or achieve a greater throughput of experiments.
This session will discuss requirements for detectors at PETRA IV and planned developments. This includes detectors with extreme time resolution, hard X-ray detection, and the challenges of synchronizing multiple detectors with high-speed experiments. Since a wide portfolio of detectors are needed, another important aspect of strategy is getting access to detectors from other labs and industry.
D. Pennicard, C. Wunderer, H. Graafsma, M. Sprung, F. Westermeier, U. Lienert, A.-C. Dippel, M. v. Zimmermann
4. Experiment Control and Data Acquisition
Data acquisition infrastructure and experiment control software at Petra IV will be placed under higher strain than at present due to the complex and high-throughput experiments proposed. This session will discuss the data acquisition, storage, data compression and DAQ requirements necessary for Petra-IV experiments. Also covered will be control system approaches for high throughput experiment, integrated DAQ/control system operation, and event data models for event synchronisation from asynchronous detectors, including experiment automation and humane/machine interfaces. We will discuss the limitations of scaling current DAQ, storage and control system approaches, and project towards potential hardware and software solutions scalable to the needs of Petra IV experiments.
A. Barty, T. Kracht
5. Near Real Time Analysis and Offline Data Processing
Online feedback and near real time analysis are essential to guiding the course of experiments. We will discuss these needs for various experiments proposed at Petra IV. Data reduction through either event triggering, or near real time data analysis where results are saved rather than raw data, will become increasingly important aspects of experiments. For offline analysis, remote analysis performed on raw data retained at DESY will become the norm with the goal being for users to take home reduced data sets containing pre-analysed data rather than petabytes of raw data. This could be performed automatically for users during beam time If the analysis is close to parameter free and requires minimal user interaction. This session will discuss the scientific needs and potential solutions applicable to achieving this for proposed Petra IV instruments, where data analysis is moved to central infrastructure or the cloud.
A. Barty, J. Garrevoet, M. Müller, P. Staron, C. Krywka, F. Lehmkühler, J. Hakanpää, M. Sprung, M. Etter, F. Bertram, C. Shen
6. Optics Demands to Access New Science
Today’s focusing optics are tailored to the coherence properties of 3rd generation sources. Large-aperture optics with diameters of several 100 µm can capture a significant portion of the X-ray beam. However, the achievable spot size is not limited by the optics, but rather by X-ray source properties. As a consequence, demands on their optical quality are rather low. Current nanofocusing optics have small apertures of only tens of µm, tailored to the lateral coherence length of today’s sources. They can reach diffraction-limited spot sizes down to 10 nm and optical quality plays a crucial role.
With the strong increase in brightness of PETRA IV, demands on X-ray optics will rise in all areas. As the X-ray source will be diffraction-limited up to 10 keV, the full beam can in principle be captured and focused, limited in performance only due to optics quality. Experiments at higher X-ray energies or with high energy resolution will also experience these brightness gains. To fully exploit the potential of PETRA IV, optics need to be adapted in size, improved in terms of aberrations, and be able to handle higher X-ray intensities. In addition, multi-stage focusing schemes are desired to tailor the beam and realize adaptable focus conditions.
The session aims to discuss current technological developments towards PETRA IV optics and to identify critical needs in optics development in order to drive science at PETRA IV.
F. Seiboth, M. Sprung, T. Salditt, U. Lienert
7. Positioning and Stability Requirements
For the ground-breaking experiments planned at PETRA IV, it is crucial to prevent relative movements between the various components. Any disturbance in the stability of the beamline optics or the experimental apparatus has a direct effect on the measurement performance and should be avoided either by super stable setting or by fast and precise correction procedures. Both methods require at least modern production methods of experimental equipment very accurate position detection and powerful new control concepts.
To figure out the basic requirements in stability and the special demands on PETRA IV Experimental setups in terms of Nanometer-Positioning and how we can implement these, we want to consider all aspects for ultra-stable mechanics and precise positioning in this workshop.
Main questions to be considered are: How can we influence the stability of setups? What is the best solution for precise positioning and position tracking? How can we implement new measuring and control concepts for positioning and vibrations? What are the minimal requirements on the experimental settings in terms of positioning, stability, environmental conditions and handling of the samples?
R. Döhrmann, M. Sprung, T. Salditt, F. Bertram, C. Shen, J. Garrevoet, U. Lienert
8. Sample Environment and Laboratories at Photon Science
This session approaches user communities and scientists at DESY from various fields, interested in future sample environment setups and equipment design. The new scientific environments have to be compatible with the high brilliant and nanometer focused, coherent beam of the PETRA IV light source. PETRA IV will address complex experiments of future research topics, which will not be possible without new developments in the field of the scientific sample environment and on-site laboratory possibilities.
This session gives the possibility to express requirements, wishes and present ideas concerning sample environment and laboratories at PETRA IV. We would like to open discussion about the PETRA IV specific equipment, environments and concepts, which require elaborated technologies and experimental concepts.
A. Ehnes, M. Lippmann, M. Sprung, F. Westermeier, U. Lienert, P. Staron, M. Müller, C. Krywka