The design and performances of a newly built electrostatic charge state analyzer constructed to act as a spectrometer for keV/u ions are reported. It consists of two 90◦ curved electrodes enclosed by Matsuda electrodes. This setup was recently tested using Ar9+ and Ar12+ ion beams at an energy of 10 keV per charge unit. This spectrometer achieves a good separation of different charge states formed by electron capture processes during collisions between primary ions and the residual gas. Thanks to these first tests, we have identified up to three different background contributions on the detector that need to be reduced or suppressed.
@article{Jolly2022,
author = {Jolly, Mariette and Voikopoulos, Spyridon and Lamour, Emily and Méry, Alain and Bräuning-Demian, Angela and Chesnel, Jean-Yves and Gumberidze, Alexandre and Lestinsky, Michael and Macé, Stéphane and Prigent, Christophe and Ramillon, Jean-Marc and Rangama, Jimmy and Rousseau, Patrick and Schury, Daniel and Spillmann, Uwe and Steydli, Sébastien and Stöhlker, Thomas and Trassinelli, Martino and Vernhet, Dominique},
title = {Performance of a keV/u Ion Spectrometer for the FISIC Platform},
journal = {Atoms},
year = {2022},
volume = {10},
number = {4},
pages = {146},
doi = {10.3390/atoms10040146},
file = {Jolly2022.pdf:Jolly2022.pdf:PDF},
keywords = {ion spectrometer; ion-atom collisions; MCP detectors; electron capture},
owner = {daniel},
timestamp = {2023.02.03},
url = {https://www.mdpi.com/2218-2004/10/4/146}
}
We study the electron-loss-to-continuum (ELC) cusp experimentally and theoretically by comparing the ionization of U^89+ projectiles in collisions with N_2 and Xe targets, at a beam energy of 75.91 MeV/u. The coincidence measurement between the singly ionized projectile and the energy of the emitted electron is used to compare the shape of the ELC cusp at weak and strong perturbations. A significant energy shift for the centroid of the electron cusp is observed for the heavy target of Xe as compared to the light target of N_2. Our results provide a stringent test for fully relativistic calculations of double-differential cross sections performed in the first-order approximation and in the continuum-distorted-wave approach.
@article{Hillenbrand2021,
author = {Hillenbrand, P. -M. and Lyashchenko, K. N. and Hagmann, S. and Andreev, O. Yu. and Banas, D. and Benis, E. P. and Bondarev, A. I. and Brandau, C. and Filippo, E. De and Forstner, O. and Glorius, J. and Grisenti, R. E. and Gumberidze, A. and Guo, D. L. and Herdrich, M. O. and Lestinsky, M. and Litvinov, Yu. A. and Pagano, E. V. and Petridis, N. and Sanjari, M. S. and Schury, D. and Spillmann, U. and Trotsenko, S. and Vockert, M. and Voitkiv, A. B. and Weber, G. and Stöhlker, Th.},
title = {Electron-loss-to-continuum cusp in collisions of U$^{89+}$ with N$_{2}$ and Xe},
journal = {Phys. Rev. A},
year = {2021},
volume = {104},
number = {1},
pages = {012809},
month = jul,
date = {2021-07-19},
doi = {10.1103/PhysRevA.104.012809},
eprint = {2107.08923v1},
eprintclass = {physics.atom-ph},
eprinttype = {arXiv},
file = {:Hillenbrand2021.pdf:PDF;online:http\://arxiv.org/pdf/2107.08923v1:PDF},
journaltitle = {Phys. Rev. A 104, 012809 (2021)},
keywords = {physics.atom-ph},
owner = {daniel},
publisher = {American Physical Society ({APS})},
timestamp = {2021.07.20}
}
For U 89+ projectiles colliding at a beam energy of 75.91 MeV/u with a N 2 target, we present a coincidence measurement between the cusp electrons emitted under an angle of 0 ◦ with respect to the projectile beam and the photons emitted under a polar angle of 90 ◦ . This radiative-electron-capture-to-continuum cusp directly probes the theory of electron-nucleus bremsstrahlung up to the high-energy endpoint in inverse kinematics. In the present study, significant improvement with respect to the experimental accuracy has been achieved, resulting in a finer agreement between experimental and theoretical results.
@article{Hillenbrand2020,
author = {Hillenbrand, P.-M. and Hagmann, S. and Groshev, M. E. and Bana{\'{s}}, D. and Benis, E. P. and Brandau, C. and Filippo, E. De and Forstner, O. and Glorius, J. and Grisenti, R. E. and Gumberidze, A. and Guo, D. L. and Hai, B. and Herdrich, M. O. and Lestinsky, M. and Litvinov, Yu. A. and Pagano, E. V. and Petridis, N. and Sanjari, M. S. and Schury, D. and Spillmann, U. and Trotsenko, S. and Vockert, M. and Weber, G. and Yerokhin, V. A. and Stöhlker, Th.},
title = {Radiative electron capture to the continuum in U89$\mathplus$$\mathplus$N2 collisions: Experiment and theory},
journal = {Phys. Rev. A},
year = {2020},
volume = {101},
number = {2},
month = feb,
doi = {10.1103/physreva.101.022708},
file = {:Hillenbrand2020.pdf:PDF},
owner = {daniel},
publisher = {American Physical Society ({APS})},
timestamp = {2020.03.22}
}
Ion-ion collisions between slow (kev/u) and fast (MeV/u) ions play an important role in for example astrophysical or inertial fusion plasmas as well as in ion-matter interaction. In this regime the energy transfer is maximum, as all primary electronic processes reach their maximum. At the same time up to today no reliable experimental data exists while being difficult to treat accurately by theory. We present the current status and performance of the low energy beam-line of the FISIC experiment which aims at filling in the blanks in this regime.
@article{Schury2020,
author = {Schury, D and M{\'{e}}ry, A and Ramillon, J M and Adoui, L and Chesnel, J-Y and L{\'{e}}vy, A and Mac{\'{e}}, S and Prigent, C and Rangama, J and Rousseau, P and Steydli, S and Trassinelli, M and Vernhet, D and Gumberidze, A and Stöhlker, Th and Bräuning-Demian, A and Hahn, C and Spillmann, U and Lamour, E},
title = {The low energy beamline of the {FISIC} experiment: current status of construction and performance},
journal = {J. Phys. Conf. Ser.},
year = {2020},
volume = {1412},
pages = {162011},
month = jan,
doi = {10.1088/1742-6596/1412/16/162011},
file = {:Schury2020.pdf:PDF},
owner = {daniel},
publisher = {{IOP} Publishing},
timestamp = {2020.06.14}
}
Electron-impact ionisation cross sections of tungsten ions in the energy range from the ionisation threshold to 1000 eV were measured. The experimental cross sections are compared with results from sub-configuration averaged distorted wave calculations. Derived plasma rate coefficients are provided for convenient use in plasma modelling.
@article{Schury2020b,
author = {Schury, D. and Becker, A. and Jr, A. Borovik and Ebinger, B. and Gharaibeh, M.F. and Hellhund, J. and Huber, K. and Rausch, J. and Spruck, K. and Jin, F.},
title = {Electron-impact ionisation of Wq+ ions with 1 ≤ q ≤ 19},
journal = {J. Phys. Conf. Ser.},
year = {2020},
volume = {1412},
pages = {152011},
doi = {10.1088/1742-6596/1412/15/152011},
file = {Schury2020b.pdf:Schury2020b.pdf:PDF},
owner = {daniel},
timestamp = {2021.01.18},
url = {https://iopscience.iop.org/article/10.1088/1742-6596/1412/15/152011}
}
In this work, we present a pilot experiment in the experimental storage ring (ESR) at GSI devoted to impact parameter sensitive studies of inner shell atomic processes for bare and He-like xenon ions (Xe 54+ ,Xe 52+ ) colliding with neutral xenon gas atoms. The projectile and target x-rays have been measured at different observation angles for all impact parameters as well as for the impact parameter range of ∼35 - 70 fm.
@article{Gumberidze2020,
author = {Gumberidze, A. and Kozhuharov, C. and Zhang, R.T. and Trotsenko, S. and Kozhedub, Y.S. and Du, R.D. and Bois, H. and Beyer, F. and Blumenhagen, K-H. and Brandau, C. and Bräuning-Demian, A. and Chen, W. and Forstner, O. and Gao, B. and Gassner, T. and Grisenti, R.E. and Hagmann, S. and Hillenbrand, P-M. and Indelicato, P. and Kumar, A. and Lestinsky, M. and Litvinov, Yu.A. and Petridis, N. and Schury, D and Spillmann, U. and Trageser, C. and Trassinelli, M. and Tu, X. and Stöhlker, Th.},
title = {Impact parameter sensitive study of inner-shell atomic processes in Xe54+, Xe52+ → Xe collisions},
journal = {J. Phys. Conf. Ser.},
year = {2020},
volume = {1412},
pages = {142015},
doi = {10.1088/1742-6596/1412/14/142015},
file = {Gumberidze2020.pdf:Gumberidze2020.pdf:PDF},
owner = {daniel},
timestamp = {2021.01.18},
url = {https://iopscience.iop.org/article/10.1088/1742-6596/1412/14/142015}
}
Absolute cross sections for electron-impact single ionisation (EISI) of multiply charged tungsten ions (W q+ ) with charge states in the range 11 q 18 in the electron–ion collision energy ranges from below the respective ionisation thresholds up to 1000eV were measured employing the electron–ion crossed-beams method. In order to extend the results to higher energies, cross section calculations were performed using the subconfiguration-averaged distorted-wave (SCADW) method for electron–ion collision energies up to 150keV. From the combined experimental and scaled theoretical cross sections rate coefficients were derived which are compared with the ones contained in the ADAS database and that are based on previous configuration-averaged distorted wave (CADW) calculations of Loch et al (2005 Phys. Rev. A 72 052716). Significant discrepancies were found at the temperatures where the ions investigated here are expected to form in collisionally ionised plasmas. These discrepancies are attributed to the limitations of the CADW approach and also the more detailed SCADW treatment which do not allow for a sufficiently accurate description of the EISI cross sections particularly at the ionisation thresholds.
@article{Schury2019b,
author = {Schury, Daniel and Jr, Alexander Borovik and Ebinger, Benjamin Janosch and Jin, Fengtao and Spruck, Kaija and Muller, Alfred and Schippers, Stefan},
title = {Electron-impact single ionisation of W^{q+} ions: Experiment and theory for 11 ≤ q ≤ 18},
journal = {J. Phys. B: At., Mol. Opt. Phys.},
year = {2019},
month = oct,
doi = {10.1088/1361-6455/ab51e9},
file = {:Schury2019b.pdf:PDF},
owner = {daniel},
publisher = {{IOP} Publishing},
timestamp = {2019.10.29}
}
The performance of a newly built omega type electrostatic analyzer designed to act as an in-line charge-state purification system for ions in the kiloelectronvolt energy range is reported. The analyzer consists of a set of four consecutive electrostatic 140° concentric cylindrical electrodes enclosed by Matsuda electrodes. This setup was recently tested and validated using O 5+ , Ar 9+ , and Xe 20+ ion beams at an energy of 14 qkeV at the ARIBE facility. A resolving power of 10.5 and a transmission of 100% of the desired charge state are measured allowing a good purification of incoming ion beams with charge states up to 10+ and a fairly good purification for charge states at least up to 20+. In comparison with other in-line solutions such as the Wien filter, our system has the advantage of being purely electrostatic and therefore lacking common drawbacks as, for example, hysteresis.
@article{Schury2019a,
author = {Schury, Daniel and Kumar, Ajit and M{\'{e}}ry, Alain and Chesnel, Jean-Yves and L{\'{e}}vy, Anna and Mac{\'{e}}, St{\'{e}}phane and Prigent, Christophe and Ramillon, Jean-Marc and Rangama, Jimmy and Rousseau, Patrick and Steydli, S{\'{e}}bastien and Trassinelli, Martino and Vernhet, Dominique and Lamour, Emily},
title = {An electrostatic in-line charge-state purification system for multicharged ions in the kiloelectronvolt energy range},
journal = {Rev. Sci. Instrum.},
year = {2019},
volume = {90},
number = {8},
pages = {083306},
month = aug,
doi = {10.1063/1.5093407},
file = {:Schury2019a.pdf:PDF},
owner = {daniel},
publisher = {{AIP} Publishing},
timestamp = {2019.08.22}
}
In this work a newly constructed experiment delivering spin-polarized electron beams located at the GSI Helmholtzzentrum für Schwerionenforschung will be described. It will be used at storage ring facilities as well as in small-scale laboratory experiments. The collaboration of a number of hessian universities in the LOEWE excellence cluster ELCH to study the atomic and molecular properties of chiral molecules discovered the lack of a source of spin-polarized electrons in the energy range of a few hundred electronvolts up to several kiloelectronvolts. Currently the setup is able to deliver electron beam intensities up to 50 μA at energies between 100 eV and 10 keV and with a transversal degree of polarization of 25%. Mounted on a compact rack, the setup is ready for use at different experiment places.
@phdthesis{Schury2017,
author = {Schury, Daniel},
title = {{A}ufbau und {C}harakterisierung einer {Q}uelle spinpolarisierter {E}lektronen für zukünftige {S}toßexperimente mit chiralen {M}olekülen},
school = {Justus-Liebig-Universität Giessen},
year = {2017},
type = {phdthesis},
month = dec,
file = {:S/Schury2017.pdf:PDF;:Schury2017.pdf:PDF},
institution = {Justus-Liebig-Universität Gießen},
language = {Deutsch},
pages = {60},
pagetotal = {120},
subtitle = {Construction and characterization of a spin-polarized electron source for future experiments with chiral molecules},
url = {http://geb.uni-giessen.de/geb/volltexte/2017/13417/}
}
In this work, we present a pilot experiment in the experimental storage ring (ESR) at GSI devoted to impact parameter sensitive studies of inner shell atomic processes for low-energy (heavy-) ion-atom collisions. The experiment was performed with bare and He-like xenon ions (Xe^54+ , Xe$^52+) colliding with neutral xenon gas atoms, resulting in a symmetric collision system. This choice of the projectile charge states was made in order to compare the effect of a filled K-shell with the empty one. The projectile and target X-rays have been measured at different observation angles for all impact parameters as well as for the impact parameter range of 35–70 fm.
@article{Gumberidze2017,
author = {Gumberidze, A. and Kozhuharov, C. and Zhang, R.T. and Trotsenko, S. and Kozhedub, Y.S. and DuBois, R.D. and Beyer, H.F. and Blumenhagen, K.-H. and Brandau, C. and Bräuning-Demian, A. and Chen, W. and Forstner, O. and Gao, B. and Gassner, T. and Grisenti, R.E. and Hagmann, S. and Hillenbrand, P.-M. and Indelicato, P. and Kumar, A. and Lestinsky, M. and Litvinov, Yu. A. and Petridis, N. and Schury, D. and Spillmann, U. and Trageser, C. and Trassinelli, M. and Tu, X. and Stöhlker, Th.},
title = {Impact parameter sensitive study of inner-shell atomic processes in the experimental storage ring},
journal = {Nucl. Instrum. Methods Phys. Res., Sect. B},
year = {2017},
volume = {408},
pages = {27--30},
month = oct,
issn = {0168-583X},
doi = {10.1016/j.nimb.2017.04.090},
file = {Gumberidze2017.pdf:Gumberidze2017.pdf:PDF},
publisher = {Elsevier {BV}},
url = {http://www.sciencedirect.com/science/article/pii/S0168583X17305402}
}
Electron-impact single ionization of W^19+ ions has been studied both experimentally and theoretically. By employing the crossed-beams method, absolute cross sections have been measured in the energy range from the ionization onset up to 1000 eV. Theoretical calculations of the ionization-cross-section function were performed using the configuration-averaged distorted-wave method for electron-ion collision energies up to 150 keV. Contributions of excited long-lived primary-ion-beam admixtures were taken into account. The role of different competing ionization mechanisms contributing to the studied cross section is discussed. Plasma rate coefficients have been inferred and are presented in parametrized form.
@article{Borovik2016,
author = {Borovik, Alexander and Ebinger, Benjamin and Schury, Daniel and Schippers, Stefan and Müller, Alfred},
title = {Electron-impact single ionization of W^{19+} ions},
journal = {Phys. Rev. A},
year = {2016},
volume = {93},
number = {1},
pages = {012708},
month = jan,
issn = {2469-9934},
doi = {10.1103/physreva.93.012708},
file = {:Borovik2016.pdf:PDF},
publisher = {American Physical Society ({APS})},
url = {http://dx.doi.org/10.1103/PhysRevA.93.012708}
}
Electron-impact ionization of tungsten ions has been measured in the energy range from threshold up to 1000 eV. Configuration-averaged distorted wave calculations were used to explain the experimental data.
@article{Borovik2015,
author = {Borovik, A and Schury, D and Ebinger, B and Spruck, K and Becker, A and Gharaibeh, M F and Rausch, J and Schippers, S and Müller, A},
title = {Electron-impact ionization of tungsten ions},
journal = {J. Phys. Conf. Ser.},
year = {2015},
volume = {635},
number = {5},
pages = {052040},
month = sep,
doi = {10.1088/1742-6596/635/5/052040},
file = {:Borovik2015.pdf:PDF},
publisher = {{IOP} Publishing}
}
The photon-ion merged-beams technique has been employed at the new Photon-Ion spectrometer at PETRA III for measuring multiple photoionization of Xe^q+ (q = 1–5) ions. Total ionization cross sections have been obtained on an absolute scale for the dominant ionization reactions of the type hν + Xe^q+ -> Xe^r+ + (q − r)e^− with product charge states q + 2 ≤r ≤$ q + 5. Prominent ionization features are observed in the photon-energy range 650–750 eV, which are associated with excitation or ionization of an inner-shell 3d electron. Single-configuration Dirac–Fock calculations agree quantitatively with the experimental cross sections for non-resonant photoabsorption, but fail to reproduce all details of the measured ionization resonance structures.
@article{Schippers2014,
author = {Schippers, S and Ricz, S and Buhr, T and Borovik, A and Hellhund, J and Holste, K and Huber, K and Schäfer, H-J and Schury, D and Klumpp, S and Mertens, K and Martins, M and Flesch, R and Ulrich, G and Rühl, E and Jahnke, T and Lower, J and Metz, D and Schmidt, L P H and Schöffler, M and Williams, J B and Glaser, L and Scholz, F and Seltmann, J and Viefhaus, J and Dorn, A and Wolf, A and Ullrich, J and Müller, A},
title = {Absolute cross sections for photoionization of X^{q+} ions (1 ≤ q ≤ 5) at the 3d ionization threshold},
journal = {J. Phys. B: At., Mol. Opt. Phys.},
year = {2014},
volume = {47},
number = {11},
pages = {115602},
month = may,
issn = {1361-6455},
doi = {10.1088/0953-4075/47/11/115602},
file = {:Schippers_JPB47(2014)115602.pdf:PDF},
publisher = {{IOP} Publishing},
url = {http://dx.doi.org/10.1088/0953-4075/47/11/115602}
}
A photon-ion merged beam endstation has been set up at the variable polarization XUV-beamline P04 of PETRA III in Hamburg. In a commissioning experiment first results could be obtained for multiple photoionization of Xe^q+ ions (q=1,2,..,5) at photon energies around the 3d ionization threshold.
@article{Ricz2014,
author = {Ricz, S and Schippers, S and Buhr, T and Holste, K and Jr, A Borovik and Hellhund, J and Schäfer, H-J and Schury, D and Klumpp, S and Mertens, K and Martins, M and Flesch, R and Ulrich, G and Rühl, E and Lower, J and Jahnke, T and Metz, D and Schmidt, L and Schöffler, M and Williams, J B and Dörner, R and Glaser, L and Scholz, F and Seltmann, J and Viefhaus, J and Dorn, A and Wolf, A and Ullrich, J and Müller, A},
title = {First light on 3d photoionization of multiply charged xenon ions: a new photon-ion merged beam setup at {PETRA} {III}},
journal = {J. Phys. Conf. Ser.},
year = {2014},
volume = {488},
number = {14},
pages = {142006},
month = apr,
doi = {10.1088/1742-6596/488/14/142006},
file = {:Ricz_2014_J._Phys.__Conf._Ser._488_142006.pdf:PDF},
publisher = {{IOP} Publishing},
url = {http://stacks.iop.org/1742-6596/488/i=14/a=142006}
}