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The Helmholtz-Zentrum Potsdam GFZ German Research Centre for Geosciences is one of the Associate Analysis Centers of the International Doppler Orbitography and Radiopositioning Integrated by Satellite (DORIS) Service (IDS). In the framework of a recent reprocessing campaign for the International Terrestrial Reference Frame (ITRF) the suite of DORIS-derived satellite products was extended and improved with respect to reference frame determination. Among others the Copernicus Sentinel-3A/3B and 6A Michael Freilich (MF) satellites were used for this purpose. The orbits were generated based on DORIS-only and on the combination of DORIS and Satellite Laser Ranging (SLR) observations, and attempts were made to optimize their accuracy. Also for these satellites, GFZ generates Global Positioning System (GPS) based orbits within the Copernicus Precise Orbit Determination (CPOD) quality working group (CPOD-QWG). The GPS orbits contribute to a combined CPOD orbit solution, which is assumed to have superior absolute accuracy and minimal residual systematic errors. The DORIS-only, the combined DORIS and SLR, and the GPS-only orbits are compared to the CPOD combined solution serving as reference solution. The accuracy of the orbits shows up in radial direction for all techniques and combinations with values of 0.60 to 0.82 cm. In transverse and normal direction the RMS values achieved with GPS are up to around 50% lower as with DORIS, which sizes at around 1.5-2 cm. Subsequently the reference points of the observation techniques were estimated. With a multi-technique approach, a center-of-mass deviation according to Montenbruck et al. (2017) could be reproduced for Sentinel-3A. In addition, for both Sentinel-3 satellites the DORIS reference point values show a deviation in normal direction of 8-9 mm and a drift in radial direction of about 3mm/year with respect to manufacturer’s data, reference point values for Sentinel-6A (MF) show a good agreement. With the confidence gained on the DORIS-only orbit solutions, weekly local reference frames are computed for each of the three satellites as well as a combined solution and evaluated in terms of the reference frame defining parameters, i.e. origin, scale, and orientation. The accuracy achieved here is in the range of a few mm to cm region. The scale remains stable, except for Sentinel-3A, which shows a scale drift of about -1.5 , whose cause is not clear yet. Standard deviations of station coordinate residuals (North, East, Up) are in the range of 2-4 mm, 5-9 mm and 5-7 mm respectively.

On a Wendelstein 7-X (W7-X), an alkali metal beam (AMB) diagnostic system was installed in order to measure the plasma edge electron density profiles and turbulence transport. A sodium beam was injected in the plasma, and the light emission was observed by an optical system. During the last operation phase, OP1.2b campaign trial spectral measurements were performed with a dedicated optical branch. The results showed the emergence of potential CX lines in the light spectra during sodium injection. The lines were identified as Carbon III, which were the dominant lines observed by other diagnostics at the edge plasma. Based on these results, an additional dedicated optical system was developed and installed in 2021 for the upcoming operational phase, OP2. The optics were designed for multiple purposes: spectral measurements for the AMB system and for a He/Ne gas jet. The system was designed to allow implementation of further diagnostics on this port later (e.g., coherence imaging system). The details of the implementation of the design requirements and the main challenges of the manufacturing process and installation are discussed in this paper.

Drifts affect particle, momentum, and energy transport in the scrape-off layer (SOL) of tokamaks and stellarators, altering plasma flows and creating asymmetries between divertors. To understand how drifts affect SOL transport in the W7-X island divertor, an experiment was performed to compare plasmas with matched core parameters but opposite magnetic field directions, and therefore opposite drift transport directions. Parallel flow measurements made with coherence imaging spectroscopy are interpreted with the aid of a diagnostic forward model and a 1D simple SOL model that includes the E × B drift. In low-density plasmas ( n ‾ e < 2 × 10 19 m−3), the poloidal E × B drift induces a large poloidal density asymmetry within the island SOL, as measured by divertor Langmuir probes. This in turn causes the parallel flow stagnation point to shift from the position halfway between targets to the X-point in the drift direction, leading to near-unidirectional flow throughout the SOL. As density increases, the effects of the poloidal E × B drift decrease substantially, resulting in a smaller density asymmetry and the development of a counter-streaming flow pattern. For the entire density range probed in this experiment ( n ‾ e = 1.5 − 6 × 10 19 m−3), the experimental observations are more consistent with the effects of the poloidal E × B drift than the radial E × B drift.

OBJECTIVEClinical evidence on giant intracranial aneurysms (GIAs), intracranial aneurysms with a diameter of at least 25 mm, is limited. The authors aimed to investigate the natural history, case fatality, and treatment outcomes of ruptured and unruptured GIAs.METHODSIn this international observational registry study, patients with a ruptured or unruptured GIA received conservative management (CM), surgical management (SM), or endovascular management (EM). The authors investigated rupture rates and case fatality.RESULTSThe retrospective cohort comprised 219 patients with GIAs (21.9% ruptured GIAs and 78.1% unruptured GIAs) whose index hospitalization occurred between January 2006 and November 2016. The index hospitalization in the prospective cohort (362 patients with GIAs [17.1% ruptured and 82.9% unruptured]) occurred between December 2008 and February 2017. In the retrospective cohort, the risk ratio for death at a mean follow-up of 4.8 years (SD 2.2 years) after CM, compared with EM and SM, was 1.63 (95% CI 1.23–2.16) in ruptured GIAs and 3.96 (95% CI 2.57–6.11) in unruptured GIAs. In the prospective cohort, the 1-year case fatality in ruptured GIAs/unruptured GIAs was 100%/22.0% during CM, 36.0%/3.0% after SM, and 39.0%/12.0% after EM. Corresponding 1-year rupture rates in unruptured GIAs were 25.0% during CM, 1.2% after SM, and 2.5% after EM. In unruptured GIAs, the HR for death within the 1st year in patients with posterior circulation GIAs was 6.7 (95% CI 1.5–30.4, p < 0.01), with patients with a GIA at the supraclinoid internal carotid artery as reference. Different sizes of unruptured GIAs were not associated with 1-year case fatality.CONCLUSIONSRupture rates for unruptured GIAs were high, and the natural history and treatment outcomes for ruptured GIAs were poor. Patients undergoing SM or EM showed lower case fatality and rupture rates than those undergoing CM. This difference in outcome may in part be influenced by patients in the CM group having been found poor candidates for SM or EM.Clinical trial registration no.: NCT02066493 (clinicaltrials.gov)

Objective: The proportion of elderly patients >65 as well as the incidence of traumatic brain injury (TBI) in this age group are increasing. We have evaluated and compared the outcome after traumatic brain injury (TBI) and decompressive craniectomy (DC) in patients aged ≤65 years versus [for full text, please go to the a.m. URL]

This dataset provides Rapid Science Orbits (RSO) from the Low Earth Orbiter (LEO) satellite SAC-C. It is part of the compilation of GFZ RSO products for various LEO missions and the appropriate GNSS constellation in sp3 format. The individual solutions for each satellite mission are published with individual DOI as part of the compilation (Schreiner et al., 2022). • The SAC-C RSO cover the period from 2000 202 to 2010 247 The LEO RSOs in version 1 are generated based on the 24-hour GPS RSOs in two pieces for the actual day with arc lengths of 14 hours and overlaps of 2 hours. One starting at 22:00 and ending at 12:00, one starting at 10:00 and ending at 24:00. For day overlapping arcs two 24h GNSS constellations are concatenated. The accuracy of the LEO RSOs is at the level of 1-2 cm in terms of SLR validation. Each solution in version 1 is given in the Conventional Terrestrial Reference System (CTS) based on the IERS 2003 conventions and related to the ITRF-2008 reference frame. The exact time covered by an arc is defined in the header of the files and indicated as well as in the filename.

This dataset provides Rapid Science Orbits (RSO) from the Low Earth Orbiter (LEO) satellite CHAMP. It is part of the compilation of GFZ RSO products for various LEO missions and the appropriate GNSS constellation in sp3 format. The individual solutions for each satellite mission are published with individual DOI as part of the compilation (Schreiner et al., 2022). • The CHAMP RSO cover the period from 2000 202 to 2010 247 The LEO RSOs in version 1 are generated based on the 24-hour GPS RSOs in two pieces for the actual day with arc lengths of 14 hours and overlaps of 2 hours. One starting at 22:00 and ending at 12:00, one starting at 10:00 and ending at 24:00. For day overlapping arcs two 24h GNSS constellations are concatenated. The accuracy of the LEO RSOs is at the level of 1-2 cm in terms of SLR validation. Each solution in version 1 is given in the Conventional Terrestrial Reference System (CTS) based on the IERS 2003 conventions and related to the ITRF-2008 reference frame. The exact time covered by an arc is defined in the header of the files and indicated as well as in the filename.

This dataset provides Rapid Science Orbits (RSO) from the Low Earth Orbiter (LEO) satellite TanDEM-X. It is part of the compilation of GFZ RSO products for various LEO missions and the appropriate GNSS constellation in sp3 format. The individual solutions for each satellite mission are published with individual DOI as part of the compilation (Schreiner et al., 2022). • The TanDEM-X RSO cover the period: o from 2010 173 to up-to-date The LEO RSOs in version 1 are generated based on the 24-hour GPS RSOs in two pieces for the actual day with arc lengths of 14 hours and overlaps of 2 hours. One starting at 22:00 and ending at 12:00, one starting at 10:00 and ending at 24:00. For day overlapping arcs two 24h GNSS constellations are concatenated. The accuracy of the LEO RSOs is at the level of 1-2 cm in terms of SLR validation. Each solution in version 1 is given in the Conventional Terrestrial Reference System (CTS) based on the IERS 2003 conventions and related to the ITRF-2008 reference frame. The exact time covered by an arc is defined in the header of the files and indicated as well as in the filename. Additional Information Orbital products describe positions and velocities of satellites, be it the Global Navigation Satellite System (GNSS) satellites or Low Earth Orbiter (LEO) satellites. These orbital products can be divided into the fastest available ones, the Near Realtime Orbits (NRT), which are mostly available within 15 to 60 minutes delay, followed by Rapid Science Orbit (RSO) products with a latency of two days and finally the Precise Science Orbit (PSO) which, with a latency of up to a few weeks, are the most delayed. The absolute positional accuracy increases with the time delay.

This dataset provides Rapid Science Orbits (RSO) from the Low Earth Orbiter (LEO) satellite TerraSAR-X. It is part of the compilation of GFZ RSO products for various LEO missions and the appropriate GNSS constellation in sp3 format. The individual solutions for each satellite mission are published with individual DOI as part of the compilation (Schreiner et al., 2022). • The TerraSAR-X RSO cover the period - from 2007 264 to up-to-date The LEO RSOs in version 2 are generated based on the 30-hour GPS RSOs in two pieces for the actual day with arc lengths of 14 hours and overlaps of 2 hours. One starting at 22:00 and ending at 12:00, one starting at 10:00 and ending at 24:00. Due to the extended length of the constellation, there is no need to concatenate several constellations for day-overlapping arcs. The accuracy of the LEO RSOs is at the level of 1-2 cm in terms of SLR validation. Each solution in version 2 is given in the Conventional Terrestrial Reference System (CTS) based on the IERS 2010 conventions and related to the ITRF-2014 reference frame. The exact time covered by an arc is defined in the header of the files and indicated as well as in the filename.

Orbital products describe positions and velocities of satellites, be it the Global Navigation Satellite System (GNSS) satellites or Low Earth Orbiter (LEO) satellites. These orbital products can be divided into the fastest available ones, the Near Realtime Orbits (NRT, Zitat), which are mostly available within 15 to 60 minutes delay, followed by Rapid Science Orbit (RSO, Zitat) products with a latency of two days and finally the Precise Science Orbit (PSO) which, with a latency of up to a few weeks or longer in the case of reprocessing campaigns, are the most delayed. The absolute positional accuracy increases from NRT to PSO. This dataset compiles the PSO products for various LEO missions in sp3 format in processing version 2. LEO Satellites: - ENVISAT - Jason-1 - Jason-2 - Jason-3 - Sentinel-3A - Sentinel-3B - Sentinel-6A - TOPEX Each solution follows specific requirements and parametrizations which are named in the respective processing metric table.

This dataset provides Rapid Science Orbits (RSO) from the Low Earth Orbiter (LEO) satellite GRACE-FO-2. It is part of the compilation of GFZ RSO products for various LEO missions and the appropriate GNSS constellation in sp3 format. The individual solutions for each satellite mission are published with individual DOI as part of the compilation (Schreiner et al., 2022). • The GRACE-FO RSO cover the period: - from 2019 049 to up-to-date The LEO RSOs in version 2 are generated based on the 30-hour GPS RSOs in two pieces for the actual day with arc lengths of 14 hours and overlaps of 2 hours. One starting at 22:00 and ending at 12:00, one starting at 10:00 and ending at 24:00. Due to the extended length of the constellation, there is no need to concatenate several constellations for day-overlapping arcs. The accuracy of the LEO RSOs is at the level of 1-2 cm in terms of SLR validation. Each solution in version 2 is given in the Conventional Terrestrial Reference System (CTS) based on the IERS 2010 conventions and related to the ITRF-2014 reference frame. The exact time covered by an arc is defined in the header of the files and indicated as well as in the filename.

There is an ongoing global effort to improve the Space geodetic techniques contributing to the Global terrestrial reference frames, which do not yet fulfill the Global Geodetic Observing System (GGOS) scientific requirements. Next-generation Global Navigation Satellite Systems (NextGNSS) satellites are planned to be equipped with optical inter-satellite links and ultra-stable clocks. The motivation of the study is to assess the improvement in the reference frames and Earth orientation parameters (EOP)achieved by the NextGNSS. In addition, transmitters on NextGNSS satellites for Very Long Baseline Interferometry observations (VLBI) are envisaged that will result in co-location in Space in addition to co-location on the ground between the Space geodetic techniques. The VLBI will observe the satellites along with the radio sources realizing the ICRF (International Celestial Reference Frame). This will empower the NextGNSS to directly determine the Earth's Rotation angle, which is otherwise impossible. Furthermore, it would allow for independent validation of satellite orbits. For this study, we will investigate multiple scenarios, such as having a NextGNSS satellite constellation with and without VLBI transmitters, and determine the improvement in the station positions and EOP.

This dataset provides Rapid Science Orbits (RSO) from the Low Earth Orbiter (LEO) satellite GRACE-A. It is part of the compilation of GFZ RSO products for various LEO missions and the appropriate GNSS constellation in sp3 format. The individual solutions for each satellite mission are published with individual DOI as part of the compilation (Schreiner et al., 2022). • The GRACE RSO cover the period: - GRACE-A from 2004 200 to 2017 334 (this DOI) - GRACE-B from 2004 200 to 2017 245 The LEO RSOs in version 1 are generated based on the 24-hour GPS RSOs in two pieces for the actual day with arc lengths of 14 hours and overlaps of 2 hours. One starting at 22:00 and ending at 12:00, one starting at 10:00 and ending at 24:00. For day overlapping arcs two 24h GNSS constellations are concatenated. The accuracy of the LEO RSOs is at the level of 1-2 cm in terms of SLR validation. Each solution in version 1 is given in the Conventional Terrestrial Reference System (CTS) based on the IERS 2003 conventions and related to the ITRF-2008 reference frame. The exact time covered by an arc is defined in the header of the files and indicated as well as in the filename.

The optimized superconducting stellarator Wendelstein 7-X (W7-X) is equipped with an island divertor for energy control and efficient pumping. We investigated the performance of the island divertor in terms of gas exhaust. For this purpose we have installed 18 pressure gauges in the vacuum vessel. This allowed us to determine the exhaust efficiency, the leakage, the collection efficiency and the compression ratio of the island divertor. These quantities depended strongly on the magnetic configuration. The best performance was obtained in the high-iota configuration. The exhaust efficiency was 2.9%, significantly higher than in the standard configuration (0.44%), and the maximum neutral compression was about 80. The high-iota configuration appears particularly promising for long-pulse operation of W7-X.

Orbital products describe positions and velocities of satellites, be it the Global Navigation Satellite System (GNSS) satellites or Low Earth Orbiter (LEO) satellites. These orbital products can be divided into the fastest available ones, the Near Realtime Orbits (NRT), which are mostly available within 15 to 60 minutes delay, followed by Rapid Science Orbit (RSO) products with a latency of two days and finally the Precise Science Orbit (PSO) which, with a latency of up to a few weeks, are the most delayed. The absolute positional accuracy increases with the time delay. This dataset compiles the RSO products for various LEO missions and the appropriate GNSS constellation in sp3 format. The individual solutions for each satellite mission are published with individual DOI as part of this compilation. GNSS Constellation: • GNSS 24h (v01) • GNSS 30h (v02) LEO Satellites: • CHAMP • GRACE • GRACE-FO • SAC-C • TanDEM-X/ TerraSAR-X Each solution is given in the Conventional Terrestrial Reference System (CTS). • The GNSS RSOs are 30-hour long arcs starting at 21:00 the day before the actual day and ending at 03:00 the day after. The accuracy of the GPS RSO sizes at the 3-cm level in terms of RMS values of residuals after Helmert transformation onto IGS combined orbit solutions (Version 1 GNSS RSOs are 24-hour long arcs starting at 00:00 and ending at 24:00 the actual day). • The LEO RSOs are generated based on these 30-hour GNSS RSOs in two pieces for the actual day with arc lengths of 14 hours and overlaps of 2 hours. One starting at 22:00 and ending at 12:00, one starting at 10:00 and ending at 24:00. The accuracy of the LEO RSOs is at the level of 1-2 cm in terms of SLR validation. The exact time covered by an arc is defined in the header of the files and indicated as well as in the filename. This dataset compiles RSO products for various LEO missions and the corresponding GNSS constellation in sp3 format in a revised processing version 2. The switch from previous version 1 to 2 was performed on 18-Feb-2019. Major changes from version 1 to 2 are the change from IERS 2003 to IERS 2010 conventions and ITRF 2008 to ITRF-2014, as well as the temporal extension of the GNSS constellation from previous 24 hours (version 1) to 30 hours (version 2) arcs. This temporal expansion eliminates the chaining of two consecutive 24-hour GNSS constellation solutions previously used to process day-overlapping LEO arcs in Version 1. This 24h GNSS constellation (Version 1) will continue to operate and be stored on the ISDC ftp server, as discussed in more detail in Section 8.1. All RSO LEO arcs will no longer be continued in version 1 after the changeover date and will only be available in version 2 since then.

This dataset provides Rapid Science Orbits (RSO) from the Low Earth Orbiter (LEO) satellite GRACE-FO-1. It is part of the compilation of GFZ RSO products for various LEO missions and the appropriate GNSS constellation in sp3 format. The individual solutions for each satellite mission are published with individual DOI as part of the compilation (Schreiner et al., 2022). • The GRACE-FO RSO cover the period: - from 2019 049 to up-to-date The LEO RSOs in version 2 are generated based on the 30-hour GPS RSOs in two pieces for the actual day with arc lengths of 14 hours and overlaps of 2 hours. One starting at 22:00 and ending at 12:00, one starting at 10:00 and ending at 24:00. Due to the extended length of the constellation, there is no need to concatenate several constellations for day-overlapping arcs. The accuracy of the LEO RSOs is at the level of 1-2 cm in terms of SLR validation. Each solution in version 2 is given in the Conventional Terrestrial Reference System (CTS) based on the IERS 2010 conventions and related to the ITRF-2014 reference frame. The exact time covered by an arc is defined in the header of the files and indicated as well as in the filename.

This dataset provides Rapid Science Orbits (RSO) from the Low Earth Orbiter (LEO) satellite GRACE-A. It is part of the compilation of GFZ RSO products for various LEO missions and the appropriate GNSS constellation in sp3 format. The individual solutions for each satellite mission are published with individual DOI as part of the compilation (Schreiner et al., 2022). • The GRACE RSO cover the period: - GRACE-A from 2004 200 to 2017 334 - GRACE-B from 2004 200 to 2017 245 (this DOI) The LEO RSOs in version 1 are generated based on the 24-hour GPS RSOs in two pieces for the actual day with arc lengths of 14 hours and overlaps of 2 hours. One starting at 22:00 and ending at 12:00, one starting at 10:00 and ending at 24:00. For day overlapping arcs two 24h GNSS constellations are concatenated. The accuracy of the LEO RSOs is at the level of 1-2 cm in terms of SLR validation. Each solution in version 1 is given in the Conventional Terrestrial Reference System (CTS) based on the IERS 2003 conventions and related to the ITRF-2008 reference frame. The exact time covered by an arc is defined in the header of the files and indicated as well as in the filename.