The European X-ray Free Electron Laser facility produces extremely intense and short X-ray pulses... more The European X-ray Free Electron Laser facility produces extremely intense and short X-ray pulses. A diamond sensor proposed for non-invasive diagnostics of hard X-rays enables pulse-resolved beam position measurements within less than 1% uncertainty at 2.25MHz.
The XrayFeed device of Karabo [1, 2] is designed to provide spatial X-ray beam stability in terms... more The XrayFeed device of Karabo [1, 2] is designed to provide spatial X-ray beam stability in terms of drift compensation utilizing different diagnostic components at the European XFEL (EuXFEL). Our feedback systems proved to be indispensable in cutting-edge pump-probe experiments at EuXFEL. The feedback mechanism is based on a closed loop PID control algorithm [3] to steer the beam position measured by a so-called diagnostic devices to the desired centered position via defined actuator adjusting the alignment of X-ray optical elements, in our case a flat X-ray mirror system. Several diagnostic devices and actuators can be selected according to the specific experimental area where a beam position feedback is needed. In this contribution, we analyze the improvement of pointing stability of X-rays using different diagnostic devices as an input source for our feedback system. Different types of photon diagnostic devices such as gas-based X-ray monitors [4], quadrant detectors based on av...
Radiation detectors based on microchannel plates (MCP) are used for measurements of the SASE proc... more Radiation detectors based on microchannel plates (MCP) are used for measurements of the SASE process of the European XFEL. Detectors operate in a wide dynamic range from the level of spontaneous emission to the saturation level (between a few nJ and 25 mJ) and in a wide wavelength range from 0.05 nm to 0.4 nm for SASE1 and SASE2 and from 0.4 nm to 4.43 nm for SASE3. Photon pulse energies are measured by the MCPs with an anode and by a photodiode. The MCP imager measures the photon beam image with a phosphor screen. Three MCP detectors are installed, one behind each SASE undulator (SASE1, SASE2, and SASE3). Calibration and first experiments with the MCP detectors are under discussion.
The 22nd International Conference on Ultrafast Phenomena 2020, 2020
We present the first pump/probe measurements performed at the SQS instrument of the European XFEL... more We present the first pump/probe measurements performed at the SQS instrument of the European XFEL. We obtain the first characterization of the femtosecond temporal resolution and show the feasibility for the investigation of ultrafast dynamics.
Detectors based on microchannel plates (MCPs) are used to detect radiation from free-electron las... more Detectors based on microchannel plates (MCPs) are used to detect radiation from free-electron lasers. Three MCP detectors have been developed by JINR for the European XFEL (SASE1, SASE2 and SASE3 lines). These detectors are designed to operate in a wide dynamic range from the level of spontaneous emission to the SASE saturation level (between a few nJ up to 25 mJ), in a wide wavelength range from 0.05 nm to 0.4 nm for SASE1 and SASE2, and from 0.4 nm to 4.43 nm for SASE3. The detectors measure photon pulse energies with an anode and a photodiode. The photon beam image is observed with an MCP imager with a phosphor screen. At present, the SASE1 and SASE3 MCP detectors are commissioned with XFEL beams. Calibration and first measurements of photon radiation in multibunch mode are performed with the SASE1 and SASE3 MCPs. The MCP detector for SASE2 and its electronics are installed in the XFEL tunnel, technically commissioned, and are now ready for acceptance tests with the X-ray beam.
The European X-ray Free Electron Laser (EuXFEL) offers intense, coherent femtosecond pulses, resu... more The European X-ray Free Electron Laser (EuXFEL) offers intense, coherent femtosecond pulses, resulting in characteristic peak brilliance values a billion times higher than that of conventional synchrotron facilities. Such pulses result in extreme peak radiation levels of the order of terawatts cm−2 for any optical component in the beam and can exceed the ablation threshold of many materials. Diamond is considered the optimal material for such applications due to its high thermal conductivity (2052 W mK−1 at 300 K) and low absorption for hard X-rays. Grating structures were fabricated on free-standing CVD diamond of 10 µm thickness with 500 µm silicon substrate support. The grating structures were produced by electron-beam lithography at the Laboratory for Micro- and Nanotechnology, Paul Scherrer Institut, Switzerland. The grating lines were etched to a depth of 1.2 µm, resulting in an aspect ratio of 16. The characterization measurements with X-rays were performed on transmissive di...
2004 Conference on Precision Electromagnetic Measurements, 2004
The construction of an engineering model of the cold atom space clock is drawing to a close. The ... more The construction of an engineering model of the cold atom space clock is drawing to a close. The clock has four main sub-systems: the cesium tube, the command system, the laser and the microwave sources. In this paper we describe their physical package and present the tests of their performances
IEEE International Frequency Control Sympposium and PDA Exhibition Jointly with the 17th European Frequency and Time Forum, 2003. Proceedings of the 2003
The European X-ray Free-Electron Laser Facility in Germany delivers x-ray pulses with femtosecond... more The European X-ray Free-Electron Laser Facility in Germany delivers x-ray pulses with femtosecond pulse duration at a repetition rate of up to 4.5 MHz. The free-electron laser radiation is created by the self-amplified spontaneous emission (SASE) process, whose stochastic nature gives rise to shot-to-shot fluctuations in most beam properties, including spectrum, pulse energy, spatial profile, wavefront, and temporal profile. Each spectrum consisting of many spikes varies in width and amplitude that appear differently within the envelope of the SASE spectrum. In order to measure and study the SASE spectrum, the HIgh REsolution hard X-ray single-shot (HIREX) spectrometer was installed in the photon tunnel of the SASE1 undulator beamline. It is based on diamond gratings, bent crystals as a dispersive element, and a MHz-repetition-rate strip detector. It covers a photon energy range of 3 keV–25 keV and a bandwidth of 0.5% of the SASE beam. The SASE spikes are resolved with 0.15 eV separ...
The European X-ray Free Electron Laser facility produces extremely intense and short X-ray pulses... more The European X-ray Free Electron Laser facility produces extremely intense and short X-ray pulses. A diamond sensor proposed for non-invasive diagnostics of hard X-rays enables pulse-resolved beam position measurements within less than 1% uncertainty at 2.25MHz.
The XrayFeed device of Karabo [1, 2] is designed to provide spatial X-ray beam stability in terms... more The XrayFeed device of Karabo [1, 2] is designed to provide spatial X-ray beam stability in terms of drift compensation utilizing different diagnostic components at the European XFEL (EuXFEL). Our feedback systems proved to be indispensable in cutting-edge pump-probe experiments at EuXFEL. The feedback mechanism is based on a closed loop PID control algorithm [3] to steer the beam position measured by a so-called diagnostic devices to the desired centered position via defined actuator adjusting the alignment of X-ray optical elements, in our case a flat X-ray mirror system. Several diagnostic devices and actuators can be selected according to the specific experimental area where a beam position feedback is needed. In this contribution, we analyze the improvement of pointing stability of X-rays using different diagnostic devices as an input source for our feedback system. Different types of photon diagnostic devices such as gas-based X-ray monitors [4], quadrant detectors based on av...
Radiation detectors based on microchannel plates (MCP) are used for measurements of the SASE proc... more Radiation detectors based on microchannel plates (MCP) are used for measurements of the SASE process of the European XFEL. Detectors operate in a wide dynamic range from the level of spontaneous emission to the saturation level (between a few nJ and 25 mJ) and in a wide wavelength range from 0.05 nm to 0.4 nm for SASE1 and SASE2 and from 0.4 nm to 4.43 nm for SASE3. Photon pulse energies are measured by the MCPs with an anode and by a photodiode. The MCP imager measures the photon beam image with a phosphor screen. Three MCP detectors are installed, one behind each SASE undulator (SASE1, SASE2, and SASE3). Calibration and first experiments with the MCP detectors are under discussion.
The 22nd International Conference on Ultrafast Phenomena 2020, 2020
We present the first pump/probe measurements performed at the SQS instrument of the European XFEL... more We present the first pump/probe measurements performed at the SQS instrument of the European XFEL. We obtain the first characterization of the femtosecond temporal resolution and show the feasibility for the investigation of ultrafast dynamics.
Detectors based on microchannel plates (MCPs) are used to detect radiation from free-electron las... more Detectors based on microchannel plates (MCPs) are used to detect radiation from free-electron lasers. Three MCP detectors have been developed by JINR for the European XFEL (SASE1, SASE2 and SASE3 lines). These detectors are designed to operate in a wide dynamic range from the level of spontaneous emission to the SASE saturation level (between a few nJ up to 25 mJ), in a wide wavelength range from 0.05 nm to 0.4 nm for SASE1 and SASE2, and from 0.4 nm to 4.43 nm for SASE3. The detectors measure photon pulse energies with an anode and a photodiode. The photon beam image is observed with an MCP imager with a phosphor screen. At present, the SASE1 and SASE3 MCP detectors are commissioned with XFEL beams. Calibration and first measurements of photon radiation in multibunch mode are performed with the SASE1 and SASE3 MCPs. The MCP detector for SASE2 and its electronics are installed in the XFEL tunnel, technically commissioned, and are now ready for acceptance tests with the X-ray beam.
The European X-ray Free Electron Laser (EuXFEL) offers intense, coherent femtosecond pulses, resu... more The European X-ray Free Electron Laser (EuXFEL) offers intense, coherent femtosecond pulses, resulting in characteristic peak brilliance values a billion times higher than that of conventional synchrotron facilities. Such pulses result in extreme peak radiation levels of the order of terawatts cm−2 for any optical component in the beam and can exceed the ablation threshold of many materials. Diamond is considered the optimal material for such applications due to its high thermal conductivity (2052 W mK−1 at 300 K) and low absorption for hard X-rays. Grating structures were fabricated on free-standing CVD diamond of 10 µm thickness with 500 µm silicon substrate support. The grating structures were produced by electron-beam lithography at the Laboratory for Micro- and Nanotechnology, Paul Scherrer Institut, Switzerland. The grating lines were etched to a depth of 1.2 µm, resulting in an aspect ratio of 16. The characterization measurements with X-rays were performed on transmissive di...
2004 Conference on Precision Electromagnetic Measurements, 2004
The construction of an engineering model of the cold atom space clock is drawing to a close. The ... more The construction of an engineering model of the cold atom space clock is drawing to a close. The clock has four main sub-systems: the cesium tube, the command system, the laser and the microwave sources. In this paper we describe their physical package and present the tests of their performances
IEEE International Frequency Control Sympposium and PDA Exhibition Jointly with the 17th European Frequency and Time Forum, 2003. Proceedings of the 2003
The European X-ray Free-Electron Laser Facility in Germany delivers x-ray pulses with femtosecond... more The European X-ray Free-Electron Laser Facility in Germany delivers x-ray pulses with femtosecond pulse duration at a repetition rate of up to 4.5 MHz. The free-electron laser radiation is created by the self-amplified spontaneous emission (SASE) process, whose stochastic nature gives rise to shot-to-shot fluctuations in most beam properties, including spectrum, pulse energy, spatial profile, wavefront, and temporal profile. Each spectrum consisting of many spikes varies in width and amplitude that appear differently within the envelope of the SASE spectrum. In order to measure and study the SASE spectrum, the HIgh REsolution hard X-ray single-shot (HIREX) spectrometer was installed in the photon tunnel of the SASE1 undulator beamline. It is based on diamond gratings, bent crystals as a dispersive element, and a MHz-repetition-rate strip detector. It covers a photon energy range of 3 keV–25 keV and a bandwidth of 0.5% of the SASE beam. The SASE spikes are resolved with 0.15 eV separ...
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