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Physical review / A 107, 012805 (2023). doi:10.1103/PhysRevA.107.012805, We perform a study on Rayleigh scattering of highly linearly polarized hard x rays on a thin Au foil target. Inthe study the angular distribution of the scattered radiation is analyzed in a relativistic regime both within and outof the plane of polarization of the incident beam. Within this experiment we scatter a synchrotron beam with aphoton energy of 175 keV on a high-Z target foil, namely, gold. Our findings correlate well with state-of-the-artcalculations of the scattering process performed in the framework of quantum electrodynamics and may haveconsiderable impact on future experiments regarding a polarization-resolved analysis of Delbrück scattering.Furthermore, we show that the angular distribution of Rayleigh scattering can be used for a highly sensitivedetermination of the degree and orientation of the linear polarization of the incident hard-x-ray beam, if we relyon the theoretical framework., Published by Inst., Woodbury, NY

We measured the Coulomb dissociation of 16O into 4He and 12C within the FAIR Phase-0 program at GSI Helmholtzzentrum für Schwerionenforschung Darmstadt, Germany. From this we will extract the photon dissociation cross section 16O(α,γ)12C, which is the time reversed reaction to 12C(α,γ)16O. With this indirect method, we aim to improve on the accuracy of the experimental data at lower energies than measured so far. The expected low cross section for the Coulomb dissociation reaction and close magnetic rigidity of beam and fragments demand a high precision measurement. Hence, new detector systems were built and radical changes to the R3B setup were necessary to cope with the high-intensity 16O beam. All tracking detectors were designed to let the unreacted 16O ions pass, while detecting the 12C and 4He.

The GOSIP (Gigabit Optical Serial Interface Protocol) provides communication via optical fibres between multiple kinds of front-end electronics and the KINPEX PCIe receiver board located in the readout host PC. In recent years a stack of device driver software has been developed to utilize this hardware for several scenarios of data acquisition. On top of this driver foundation, several graphical user interfaces (GUIs) have been created. These GUIs are based on the Qt graphics libraries and are designed in a modular way: All common functionalities, like generic I/O with the front-ends, handling of configuration files, and window settings, are treated by a framework class GosipGUI. In the Qt workspace of such GosipGUI frame, specific sub classes may implement additional windows dedicated to operate different GOSIP front-end modules. These readout modules developed by GSI Experiment Electronics department are for instance FEBEX sampling ADCs, TAMEX FPGA-TDCs, or POLAND QFWs. For each kind of front-end the GUIs allow to monitor specific register contents, to set up the working configuration, and to interactively change parameters like sampling thresholds during data acquisition. The latter is extremely useful when qualifying and tuning the front-ends in the electronics lab or detector cave. Moreover, some of these GosipGUI implementations have been equipped with features for mostly automatic testing of ASICs in a prototype mass production. This has been applied for the APFEL-ASIC component of the PANDA experiment currently under construction, and for the FAIR beam diagnostic readout system POLAND., Proceedings of the IEEE RT2020

A new approach for measuring lifetimes of nuclear states at the electronic signal processing stage has been tested. Cerium doped lanthanum bromide inorganic scintillator crystals are used as suitable candidates for fast-timing measurements, in the sub-nanosecond region. The pulse processing of fast timing detectors has been performed using fast amplifiers together with FPGA (field-programmable gate array) based signal discrimination and time measurement in a 10 ps (rms- root mean square) TDC (time-to-digital convertor). The performance from the timing perspective has been tested in an accelerated ion-beam experiment.

Online gas-solid adsorption studies with single atom quantities of Hg, Tl, and Pb on SiO$_{2}$ and Au surfaces were carried out using short-lived radioisotopes with half-lives in the range of 4-49 s. This is a model study to measure adsorption enthalpies of superheavy elements Cn, Nh, and Fl. The short-lived isotopes were produced and separated by the gas-filled recoil separator TASCA at GSI. The products were stopped in He gas, and flushed into gas chromatography columns made of Si detectors whose surfaces were covered by SiO$_{2}$ or Au. The short-lived Tl and Pb were successfully measured by the Si detectors with the SiO$_{2}$ surface at room temperature. On the other hand, the Hg did not adsorb on the SiO$_{2}$ surface, but adsorbed on the Au surface. The results demonstrated that the adsorption properties of short-lived Hg, Tl, and Pb could be studied with this setup, and that this method is applicable to the experiment for Cn, Nh, and Fl., 半減期4$\sim$49秒の短寿命同位体を用いて、水銀(Hg), タリウム(Tl), 鉛(Pb)の単一原子レベルでのSiO$_{2}$及びAu表面への固体吸着挙動をオンライン気相実験により調べた。超重元素Cn, Nh, Flの吸着エンタルピー測定のためのモデル実験として実施した。短寿命同位体はドイツ重イオン研究所の反跳核分離装置TASCAを用いて生成・分離した。生成核はヘリウムガス中に捕集された後、SiO$_{2}$あるいはAuで表面を覆われたSi検出器で作製されたガスクロマトグラフィーカラムへと導入した。短寿命Tl及びPb同位体は室温においてSiO$_{2}$表面に吸着し、Si検出器で測定することに成功した。一方、HgはSiO$_{2}$表面には吸着せず、Au表面に吸着した。この結果より、本実験のセットアップを用いることで短寿命Hg, Tl, Pb同位体の吸着特性を調べることができると証明され、この手法がCn, Nh, Flの実験にも適用できることが確認された。

The GSI PCI express (PCIe) optical receiver (PEXOR) family PCIe boards are used as an interface for data acquisition (DAQ) from various detector front ends, linked by up to four chains of optical fiber connections. Communication with the front-end hardware is handled by the proprietary gigabit optical serial interface protocol. A trigger module trigger for pexor extends the PEXOR by additional signal connections for triggered DAQ. For several years, the PEXOR boards have been used with the DAQ framework multibranch system (MBS). On a Linux x-86 platform, the device driver software mbspex implements concurrent access to the PEXOR front ends from MBS DAQ and from separate control applications, such as the command line tool gosipcmd or hardware specific configuration graphical user interfaces. Besides the established character driver mbspex , a network driver pexornet has been developed to evaluate a lightweight DAQ system with readout from PEXOR via a user datagram protocol (UDP) socket. Therefore, common network tools can be applied for driver configuration and data debugging. Moreover, the gosipcmd tool and its adjusted application programming interface library are fully applicable also for pexornet . A simple example DAQ application with pexornet UDP readout has been implemented with the software framework DAQ backbone core (DABC), delivering the same data file format and online monitoring capabilities as MBS. Readout performance of a test setup has been measured both with MBS/ mbspex and with DABC/ pexornet .

An upgraded TASISpec setup, with the addition of a veto DSSD and the new Compex detector-germanium array, has been employed with the gas-filled recoil separator TASCA at the GSI Helmholtzzentrum für Schwerionenforschung Darmstadt, to study flerovium (element 114) decay chains. The detector upgrades along with development of new analytical techniques have improved the sensitivity of the TASISpec setup for measuring α-photon coincidences. These improvements have been assessed with test reactions. The reaction 48Ca+206,207Pb was used for verification of experimental parameters such as transmission to implantation DSSD and target-segment to α-decay correlations. The reaction 48Ca+ nat Hf was used to produce several short-lived nuclei with multiple-α decay chains to investigate pile-up event deconvolution.

Rapid in situ formation of metal carbonyl complexes with short-lived nuclides has been demonstrated to be feasible with recoiling ions formed in nuclear fusion and fission reactions. These carbonyl complexes are highly volatile and can be transported rapidly in a gas-stream to counting or chemistry devices. This method was already successfully applied in the chemical investigation of the superheavy element seaborgium (Z = 106) and appears promising for various fields of nuclear research. In this article, we give an overview on the current status of metal carbonyl complex studies with short-lived d-element isotopes.

International audience; Note from publisher: This article contains the abstract only.

Future experiments at the new accelerator facility FAIR (Facility for Antiproton and Ion Research) for the research with ion and anti-proton beams require new developments of front-end electronics to tolerate high data rate. We have developed a PCIe card and front-end cards equipped with the small form-factor pluggable (SFP) transceivers for the data transfer via optical fiber. A new protocol has been designed and implemented on the FPGAs in order to provide communication between the PCIe card and the front-end cards. The standard data acquisition (DAQ) system at GSI, multi-branch system (MBS), has been upgraded to support the PCIe cards and is working stably with the data transfer rate up to 180 Mbytes per second.

For the new experiments at FAIR like CBM new concepts of data acquisition systems have to be developed like the distribution of self-triggered, time stamped data streams over high performance networks for event building. The data acquisition backbone core DABC is designed for FAIR detector tests, readout components test, data flow investigations, and DAQ controls. All kinds of data channels (front-end systems) are connected by plug-ins into functional components of DABC like data input, combiner, scheduler, event builder, analysis and storage. On the other hand, the current GSI DAQ system MBS with its huge installed hardware base (about 100 installed, 50% outside GSI) must be integrated in any new DAQ concept. After detailed simulations now real tests (on InfiniBand clusters) of event building over networks had been performed. Several software packages (uDAPL, OpenFabric IB Verbs, MPI2) have been used to measure the performance of InfiniBand. One can achieve about 80% of the bidirectional nominal IB bandwidth of 1 GByte/s. To achieve real reliable performance with IB one needs the optional real time extensions of the latest Linux kernel 2.6.21. Some infrastructure components of the XDAQ package developed for the CMS experiment have been evaluated for DABC. The development of key components is supported by the FutureDAQ project of the European Union (FP6 I3HP JRA1).

14th International Workshop on Meson Production, Properties and Interaction, Cracow, Poland, 2 Jun 2016 - 7 Jun 2016; The European physical journal / Web of Conferences Web of Conferences : proceedings proceedings 130, 02010 (2016). doi:10.1051/epjconf/201613002010, We performed a missing-mass spectroscopy experiment of the ^12C(p, d) reaction at 2.5 GeV proton energy in order to search for eta' mesic nuclei. An excitation-energy spectrum of ^11C was obtained around the eta' production threshold. As no significant peak structure was observed in the spectrum, upper limits of the formation cross section of eta' mesic nuclei have been determined. Preliminary results of the experiment as well as future prospects are given., Published by EDP Sciences, Les Ulis

The Radioactive Isotope Beam Factory at RIKEN has been constructed to produce intense RI beams over the whole range of atomic masses. MUST2, EURICA, and MINOS detector systems together with dedicated DAQ systems are transported to RIBF from other facilities of GANIL, GSI and Irfu CEA. These data have to be merged with data of RIBFDAQ. There are two types of DAQ coupling methods. One is the common trigger configuration, and the other is the individual trigger configuration. In case of the common trigger configuration, data taken by different DAQ systems are merged in online through Ethernet. This merging is simple because the event number is the same between DAQ systems. However, run control commands and data formats are translated to adapt other DAQ systems. On the other hand, the time-stamping system is adopted for the individual trigger configuration. This case, DAQ systems run independently, and data are taken attached with time-stamp information. Raw data are converted to ROOT Tree file once. Finally, data are merged offline based on time-stamp information. Here, DAQ coupling projects in RIBF are described.

Produced in the reaction 48Ca+243Am, thirty correlated α-decay chains were observed in an experiment conducted at the GSI Helmholzzentrum fur Schwerionenforschung, Darmstadt, Germany. The decay chains are basically consistent with previous findings and are considered to originate from isotopes of element 115 with mass numbers 287, 288, and 289. A set-up aiming specifically for high-resolution charged particle and photon coincidence spectroscopy was placed behind the gas-filled separator TASCA. For the first time, γ rays as well as X-ray candidates were observed in prompt coincidence with the α-decay chains of element 115.

A high-resolution , X-ray and gamma-ray coincidence spectroscopy experiment was conducted at the GSI Helmholtzzentrum für Schwerionenforschung. Thirty correlated alpha-decay chains were detected following the fusion-evaporation reaction 48Ca + 243Am. The observations are consistent with previous assignments of similar decay chains to originate from element Z = 115. For the first time, precise spectroscopy allows the derivation of excitation schemes of isotopes along the decay chains starting with elements Z > 112. Comprehensive Monte-Carlo simulations accompany the data analysis. Nuclear structure models provide a first level interpretation.

The subject of this paper is the development and first analysis of the performance of a new booster bleed valve control logic to improve the surge margin of the booster compressor in the new BR715 turbofan. The booster compressor is driven by the LP spool of the two spool engine, comprising an aerodynamically tuned system out of fan root and booster compressor. The flow delivered at the exit of the booster compressor must be accepted by the following HP compressor. This matching is not always possible, since the rates of change of the spool speeds during transients behave differently as do pressure rise and mass flow. Hence the transient handling of the booster compressor is difficult with respect to its surge stability. To aid in this situation it is a common practice to position a booster bleed valve after the booster compressor, which passes bleed air into the bypass duct. The BR715 jet engine takes advantage of a newly developed logic driving this valve. Monitoring input parameters such as spool and flight speeds as well as altitude, the logic provides the capability of appropriately positioning the valve, thereby maintaining an optimum performance of the engine throughout the whole operating range. Furthermore the logic allows for reaction on thrust reverser deployment or more serious events such as surge and foreign object damage. Much effort has been put into the development of the newly designed transient valve logic, which in its main part is based on the rate of change of the pressure at the exit of the HP compressor. This logic ensures a sufficient surge margin in case of deceleration or reslams of the engine. A simulation of the logic was set up, connected to a synthesis program for the two spool engine and used for the development. After this basic testing, the logic was implemented in the BR715 engine, which first ran in April 1997. The actual data from basic handling tests performed with this engine were analysed and checked against simulation results. The paper describes the logic in detail and contains first results. They prove a proper working of the logic and show the strong effect of the booster bleed valve.