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1. New test of modulated electron capture decay of hydrogen-like 142Pm ions: Precision measurement of purely exponential decay

Author

F.C. Ozturk, B. Akkus, D. Atanasov, H. Beyer, F. Bosch, D. Boutin, C. Brandau, P. Bühler, R.B. Cakirli, R.J. Chen, W.D. Chen, X.C. Chen, I. Dillmann, C. Dimopoulou, W. Enders, H.G. Essel, T. Faestermann, O. Forstner, B.S. Gao, H. Geissel, R. Gernhäuser, R.E. Grisenti, A. Gumberidze, S. Hagmann, T. Heftrich, M. Heil, M.O. Herdrich, P.-M. Hillenbrand, T. Izumikawa, P. Kienle, C. Klaushofer, C. Kleffner, C. Kozhuharov, R.K. Knöbel, O. Kovalenko, S. Kreim, T. Kühl, C. Lederer-Woods, M. Lestinsky, S.A. Litvinov, Yu.A. Litvinov, Z. Liu, X.W. Ma, L. Maier, B. Mei, H. Miura, I. Mukha, A. Najafi, D. Nagae, T. Nishimura, C. Nociforo, F. Nolden, T. Ohtsubo, Y. Oktem, S. Omika, A. Ozawa, N. Petridis, J. Piotrowski, R. Reifarth, J. Rossbach, R. Sánchez, M.S. Sanjari, C. Scheidenberger, R.S. Sidhu, H. Simon, U. Spillmann, M. Steck, Th. Stöhlker, B.H. Sun, L.A. Susam, F. Suzaki, T. Suzuki, S.Yu. Torilov, C. Trageser, M. Trassinelli, S. Trotsenko, X.L. Tu, P.M. Walker, M. Wang, G. Weber, H. Weick, N. Winckler, D.F.A. Winters, P.J. Woods, T. Yamaguchi, X.D. Xu, X.L. Yan, J.C. Yang, Y.J. Yuan, Y.H. Zhang, and X.H. Zhou

Subjects
Physics, QC1-999
Abstract

An experiment addressing electron capture (EC) decay of hydrogen-like Pm60+142 ions has been conducted at the experimental storage ring (ESR) at GSI. The decay appears to be purely exponential and no modulations were observed. Decay times for about 9000 individual EC decays have been measured by applying the single-ion decay spectroscopy method. Both visually and automatically analysed data can be described by a single exponential decay with decay constants of 0.0126(7)s−1 for automatic analysis and 0.0141(7)s−1 for manual analysis. If a modulation superimposed on the exponential decay curve is assumed, the best fit gives a modulation amplitude of merely 0.019(15), which is compatible with zero and by 4.9 standard deviations smaller than in the original observation which had an amplitude of 0.23(4). Keywords: Two body weak decay, Orbital electron capture, Single particle decay spectroscopy, Heavy ion storage ring

Published
2019
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2. Electron capture of Xe54+ in collisions with H2 molecules in the energy range between 5.5 and 30.9 MeV/u

Author

Matthias Heil, M. Groothuis, S. Hagmann, R. Hensch, I. Yu. Tolstikhina, A. Khodaparast, P. J. Woods, U. Popp, T. Kausch, B. Thomas, Yu. A. Litvinov, Herbert A. Simon, M. Steck, Claudia Lederer-Woods, T. Gaßner, Tamás Szücs, Lukas Bott, U. Spillmann, Deniz Kurtulgil, Jan Glorius, T. Davinson, Klaus Blaum, R. Hess, Rene Reifarth, F. Nolden, M. S. Sanjari, T. T. Nguyen, Gy Gyürky, P. M. Hillenbrand, B. Löher, V.P. Shevelko, S. Fiebiger, Michael Lestinsky, P. Hillmann, Sergey Litvinov, B. Jurado, Th. Stöhlker, T. Kisselbach, G. Weber, M. Volknandt, Christoph Langer, B. Brückner, Sergiy Trotsenko, S. Yu. Torilov, J. Stumm, M. O. Herdrich, C. Kozhuharov, C. Hahn, Z. Slavkovská, N. Klapper, Kathrin Göbel, F. M. Kröger, N. Petridis, C. Trageser, A. Gumberidze, Saed Dababneh, P. Erbacher, Matthew Reed, G. J. Lane, O. Hinrichs, Mario Weigand, Xiu-Bo Chen, H. Törnqvist, C. Brandau, C. Wolf, and A. Taremi Zadeh

Subjects
Physics, Range (particle radiation), Ion beam, Electron capture, chemistry.chemical_element, Electron, 01 natural sciences, 7. Clean energy, 010305 fluids & plasmas, Ion, Xenon, chemistry, Excited state, 0103 physical sciences, Atomic physics, Nuclear Experiment, 010306 general physics, Storage ring
Abstract

The electron capture process was studied for Xe$^{54+}$ colliding with H$_2$ molecules at the internal gas target of the ESR storage ring at GSI, Darmstadt. Cross section values for electron capture into excited projectile states were deduced from the observed emission cross section of Lyman radiation, being emitted by the hydrogen-like ions subsequent to the capture of a target electron. The ion beam energy range was varied between 5.5 MeV/u and 30.9 MeV/u by applying the deceleration mode of the ESR. Thus, electron capture data was recorded at the intermediate and in particular the low collision energy regime, well below the beam energy necessary to produce bare xenon ions. The obtained data is found to be in reasonable qualitative agreement with theoretical approaches, while a commonly applied empirical formula significantly overestimates the experimental findings.

Published
2020

3. Impact parameter sensitive study of inner-shell atomic processes in $Xe^{54+}$ , $Xe^{52+}$ $→ Xe$ collisions

Author

A. Bräuning-Demian, Martino Trassinelli, T. Gassner, Yu. A. Litvinov, W. Chen, A. Gumberidze, Bingshui Gao, Th. Stöhlker, Oliver Forstner, H. Bois, Robert E. Grisenti, Paul Indelicato, S. Hagmann, Ashok Kumar, C. Kozhuharov, N. Petridis, P. M. Hillenbrand, K. H. Blumenhagen, R. D. Du, Xiao-Lin Tu, U. Spillmann, F. Beyer, C. Trageser, C. Brandau, Sergiy Trotsenko, Y. S. Kozhedub, Michael Lestinsky, R. Zhang, and D. Schury

Subjects
History, Work (thermodynamics), Range (particle radiation), Materials science, Pilot experiment, Projectile, chemistry.chemical_element, Computer Science Applications, Education, Ion, Xenon, chemistry, ddc:530, Atomic physics, Impact parameter, Storage ring
Abstract

31st International Conference on Photonic, Electronic and Atomic Collisions, ICPEAC XXXI, Caen, France, 23 Jul 2019 - 30 Jul 2019; Journal of physics / Conference series Conference series [...] 1412, 142015 (2020). doi:10.1088/1742-6596/1412/14/142015, Published by IOP Publ., Bristol

Published
2020

4. Determination of luminosity for in-ring reactions: A new approach for the low-energy domain

Author

H. Törnqvist, C. Brandau, B. Löher, T. Kisselbach, U. Spillmann, M. Steck, X. C. Chen, Tamás Szücs, Yu. A. Litvinov, L. Varga, R. Hensch, T. T. Nguyen, B. Thomas, Herbert A. Simon, C. Trageser, N. Klapper, O. Hinrichs, N. Petridis, M. Wang, B. Brückner, M. Groothuis, S. Yu. Torilov, Kathrin Göbel, T. Kausch, M. Volknandt, Thomas Davinson, Y. H. Zhang, Claudia Lederer-Woods, S. Fiebiger, Z. Slavkovská, T. Gaßner, Beatriz Jurado, A. Khodaparast, P. Hillmann, Christoph Langer, C. Kozhuharov, Lukas Bott, P. M. Hillenbrand, Mario Weigand, A. Taremi Zadeh, C. Wolf, R.J. Chen, Deniz Kurtulgil, U. Popp, Gyuri Gyürky, Jan Glorius, Sergey Litvinov, Xiaojuan Zhou, Thomas Stöhlker, P. Erbacher, Michael Lestinsky, Rene Reifarth, Gregory Lane, M. S. Sanjari, Matthew Reed, J. Stumm, Philip Woods, Matthias Heil, Y. M. Xing, R. Hess, A. Gumberidze, Saed Dababneh, Sergiy Trotsenko, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), and Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Normalization (statistics), Nuclear and High Energy Physics, Reaction, FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], nucl-ex, 01 natural sciences, Measure (mathematics), Luminosity, symbols.namesake, Gas target, 0103 physical sciences, Rutherford scattering, Nuclear Experiment (nucl-ex), 010306 general physics, Instrumentation, Nuclear Experiment, Physics, Ring (mathematics), Luminosity (scattering theory), 010308 nuclear & particles physics, Beam, 3. Good health, Computational physics, Domain (ring theory), symbols, Storage ring, Beam (structure)
Abstract

Luminosity is a measure of the colliding frequency between beam and target and it is a crucial parameter for the measurement of absolute values, such as reaction cross sections. In this paper, we make use of experimental data from the ESR storage ring to demonstrate that the luminosity can be precisely determined by modelling the measured Rutherford scattering distribution. The obtained results are in good agreement with an independent measurement based on the x-ray normalization method. Our new method provides an alternative way to precisely measure the luminosity in low-energy stored-beam configurations. This can be of great value in particular in dedicated low-energy storage rings where established methods are difficult or impossible to apply., 8 pages, 5 figures

Published
2020

5. High precision hyperfine measurements in Bismuth challenge bound-state strong-field QED

Author

Rodolfo Sánchez, Volker Hannen, M. Hammen, S. Kaufmann, Christopher Geppert, Matthias Schmidt, J. Meisner, Zoran Andelkovic, Yuri A. Litvinov, Stefan E. Schmidt, C. Gorges, Johannes Ullmann, Christian Weinheimer, C. Brandau, B. Maaß, W. Geithner, J. Vollbrecht, Richard C. Thompson, Kristian König, Matthias Lochmann, Markus Steck, T. Murböck, Wilfried Nörtershäuser, C. Trageser, Thomas Stöhlker, Andreas Dax, and Engineering & Physical Science Research Council (EPSRC)

Subjects
Electromagnetic field, IONS, NUCLEAR MAGNETIZATION DISTRIBUTION, Science, General Physics and Astronomy, chemistry.chemical_element, BEAM, Electron, 01 natural sciences, General Biochemistry, Genetics and Molecular Biology, Article, Bismuth, LITHIUM-LIKE IONS, 0103 physical sciences, Bound state, Physics::Atomic Physics, 010306 general physics, LASER SPECTROSCOPY, Hyperfine structure, Quantum, Physics, Multidisciplinary, Science & Technology, 010308 nuclear & particles physics, Nuclear structure, General Chemistry, Magnetic field, Multidisciplinary Sciences, chemistry, Science & Technology - Other Topics, Atomic physics, RADII
Abstract

Electrons bound in highly charged heavy ions such as hydrogen-like bismuth 209Bi82+ experience electromagnetic fields that are a million times stronger than in light atoms. Measuring the wavelength of light emitted and absorbed by these ions is therefore a sensitive testing ground for quantum electrodynamical (QED) effects and especially the electron–nucleus interaction under such extreme conditions. However, insufficient knowledge of the nuclear structure has prevented a rigorous test of strong-field QED. Here we present a measurement of the so-called specific difference between the hyperfine splittings in hydrogen-like and lithium-like bismuth 209Bi82+,80+ with a precision that is improved by more than an order of magnitude. Even though this quantity is believed to be largely insensitive to nuclear structure and therefore the most decisive test of QED in the strong magnetic field regime, we find a 7-σ discrepancy compared with the theoretical prediction., Precision measurements provide a sensitive test of fundamental constants and their uncertainties. Here the authors precisely measure the hyperfine structure splitting in bismuth ions, and report significant discrepancy with the theoretical prediction of quantum electrodynamics.

Published
2017

6. The hyperfine puzzle of strong-field bound-state QED

Author

Wilfried Nörtershäuser, J. Meisner, Yu. A. Litvinov, Benjamin Scheibe, V. M. Shabaev, M. Hammen, Volker Hannen, Richard C. Thompson, Matthias Lochmann, Florian Kraus, M. Steck, J. Vollbrecht, Andreas Dax, Kristian König, B. Maaß, B. Kresse, Christian Gorges, T. Murböck, Leonid V. Skripnikov, Zoran Andelkovic, Andrey V. Volotka, J. Ullmann, Stefan E. Schmidt, Christopher Geppert, Alexei F. Privalov, C. Trageser, W. Geithner, Michael Schmidt, Ch. Weinheimer, C. Brandau, Thomas Stöhlker, R. Sánchez, Michael Vogel, S. Kaufmann, Commission of the European Communities, and Engineering & Physical Science Research Council (EPSRC)

Subjects
Nuclear and High Energy Physics, General Physics, NUCLEAR MAGNETIZATION DISTRIBUTION, BEAM, Physics, Atomic, Molecular & Chemical, 01 natural sciences, Resonance (particle physics), law.invention, Magnetic moment, GSI, Highly charged ions, law, 0103 physical sciences, Bound state, Physical and Theoretical Chemistry, ION, 010306 general physics, Electron paramagnetic resonance, Hyperfine structure, Physics, Science & Technology, SPECTROSCOPY, 010308 nuclear & particles physics, Nuclear structure, Laser spectrosocpy, Condensed Matter Physics, Atomic and Molecular Physics, and Optics, Charged particle, NMR, Magnetic field, BI-209, Physics, Nuclear, Physics, Condensed Matter, Physical Sciences, 0202 Atomic, Molecular, Nuclear, Particle and Plasma Physics, Atomic physics, Storage ring
Abstract

The hyperfine splitting in heavy highly charged ions provide the means to test QED in extremely strong magnetic fields. In order to provide a meaningful test, the splitting has to be measured in H-like and Li-like ions to remove uncertainties from nuclear structure. This has been achieved at the experimental storage ring ESR but a discrepancy to the theoretical prediction of more than 7σ was observed. We report on these measurements as well as on NMR measurements that were performed to solve this issue.

Published
2019

7. Approaching the Gamow Window with Stored Ions: Direct Measurement of Xe124(p,γ) in the ESR Storage Ring

Author

Claudia Lederer-Woods, O. Hinrichs, Deniz Kurtulgil, L. Varga, R. Hensch, Matthew Reed, N. Petridis, Rene Reifarth, U. Popp, U. Spillmann, M. S. Sanjari, P. Hillmann, Sergiy Trotsenko, B. Löher, Michael Lestinsky, X. C. Chen, M. Träger, T. Kisselbach, A. Khodaparast, Lukas Bott, G. J. Lane, Yu. A. Litvinov, P. M. Hillenbrand, M. Volknandt, Thomas Rauscher, Y. M. Xing, T. Gaßner, Christoph Langer, C. Kozhuharov, Thomas Stöhlker, B. Brückner, Mario Weigand, Kathrin Göbel, T. Davinson, Gyuri Gyürky, Jan Glorius, M. Groothuis, Helmut Weick, J. Stumm, S. Yu. Torilov, P. J. Woods, Sergey Litvinov, T. T. Nguyen, P. Erbacher, H. Törnqvist, A. Gumberidze, M. Steck, Klaus Blaum, C. Brandau, Tamás Szücs, Matthias Heil, Saed Dababneh, Beatriz Jurado, C. Trageser, Andrey Surzhykov, A. Taremi Zadeh, C. Wolf, R. Hess, S. Fiebiger, D. Savran, T. Kausch, B. Thomas, Herbert A. Simon, N. Klapper, F. Nolden, and Z. Slavkovská

Subjects
Joint research, European research, Political science, 0103 physical sciences, General Physics and Astronomy, media_common.cataloged_instance, Library science, European union, 010306 general physics, 01 natural sciences, media_common
Abstract

This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant Agreement No. 682841 “ASTRUm”). This work is supported by the Helmholtz International Center for FAIR (HIC for FAIR), by the Bundesministerium fur Bildung und Forschung (BMBF) (05P15RFFAA, 05P15RGFAA), by the Science and Technology Facilities Council (STFC) UK (ST/L005824/1, ST/M001652/1, ST/M006085), by the Helmholtz-CAS Joint Research Group (HCJRG-108), and by the Helmholtz-OCPC Postdoctoral Program (GSI08). C. L. W. acknowledges support by the European Research Council (Grant Agreement ERC-2015-StG No. 677497 “DoRES”). S. D. gratefully acknowledges the support provided by the Alexander von Humboldt Foundation and the Jordanian Scientific Research Support Fund under Grant No. Bas/2/4/2014. S. Yu. T. acknowledges the support by the DAAD through Mendeleev Grant, SPbU(28999675). C. L. and J. G. thank the ExtreMe Matter Institute EMMI at GSI, Darmstadt, and JINA-CEE (NSF Grant No. PHY-1430152) for support in the framework of the EMMI/JINA-CEE Workshop “NARRS” during which this work was discussed.

Published
2019

8. Studies at the border between nuclear and atomic physics: Weak decays of highly charged ions

Author

Iris Dillmann, P. Kienle, V.P. Shevelko, F. C. Ozturk, Xiao-Lin Tu, X. L. Yan, P. J. Woods, X.W. Ma, Jan Glorius, Yu. A. Litvinov, U. Spillmann, H S Xu, X. C. Chen, NucAR Collaborations, M. Steck, Sergey Litvinov, Zygmunt Patyk, C. Brandau, P. M. Walker, F. Nolden, Robert E. Grisenti, P. M. Hillenbrand, Y. H. Zhang, Ilima, Sparc, Twbd, Hans Geissel, Paul Alois Buhler, S. Hagmann, Miodrag K. Pavicevic, C. Kozhuharov, Thomas Stöhlker, B S Gao, C. Trageser, Y Yamaguchi, Xiaojuan Zhou, R. Sánchez, Takayuki Yamaguchi, F. Suzaki, Toshio Suzuki, Klaus Blaum, A. Ozawa, Thomas Faestermann, Min Wang, S. Yu. Torilov, Gregory Lane, M. S. Sanjari, Dinko Atanasov, R. B. Cakirli, F. Bosch, Takashi Ohtsubo, Nicolas Winckler, Helmut Weick, D. H. Schneider, Roman Gernhäuser, Michael Lestinsky, Claudia Lederer-Woods, Martino Trassinelli, Christoph Langer, M. A. Najafi, A. Gumberidze, Tomohiro Uesaka, N. Petridis, Bao-Hua Sun, Rene Reifarth, and for the ILIMA, SPARC, TWBD, and NucAR Collaborations

Subjects
Physics, History, 010308 nuclear & particles physics, 0103 physical sciences, ddc:530, Präzisionsexperimente - Abteilung Blaum, Atomic physics, 010306 general physics, 01 natural sciences, Computer Science Applications, Education, Ion
Abstract

Journal of physics / Conference Series 875, 012008 (2017). doi:10.1088/1742-6596/875/2/012008, Published by IOP Publ., Bristol

Published
2017

9. CBM Collaboration

Author

T. Ablyazimov, A. Abuhoza, R. Adak, J. Adamczewski-Musch, M. Adamczyk, M.M. Aggarwal, Z. Ahammed, F. Ahmad, N. Ahmad, S. Ahmad, A. Akindinov, P. Akishin, E. Akishina, T. Akishina, V. Akishina, M. Al-Turany, E. Alexandrov, I. Alexandrov, S. Amar-Youcef, M. Anđelić, O. Andreeva, C. Andrei, A. Andronic, Yu. Anisimov, H. Appelshäuser, A. Arend, D. Argintaru, E. Atkin, S. Avdeev, R. Averbeck, M.D. Azmi, V. Baban, M. Bach, E. Badura, S. Baginyan, T. Balle, T. Balog, S. Bandyopadhyay, P. Banerjee, N. Baranova, T. Barczyk, D. Bartoş, S. Bashir, Z. Basrak, M. Baszczyk, O. Batenkov, V. Baublis, C. Baumann, M. Baznat, K.-H. Becker, T. Bel, S. Belogurov, J. Bendarouach, I. Berceanu, A. Bercuci, E. Berdermann, A. Berdnikov, Y. Berdnikov, R. Berendes, C. Bergmann, D. Bertini, O. Bertini, C. Beşliu, O. Bezshyyko, P.P. Bhaduri, A. Bhasin, A.K. Bhati, B. Bhattacharjee, A. Bhattacharyya, T.K. Bhattacharyya, S. Biswas, D. Blau, C. Blume, Yu. Bocharov, S. Böttger, M. Borysova, T. Breitner, U. Brüning, J. Brzychczyk, A. Bubak, H. Büsching, A. Bychkov, A. Byszuk, Xu Cai, M. Cãlin, Ping Cao, R. Čaplar, G. Caragheorgheopol, I. Carević, V. Cătănescu, A. Chakrabarti, S. Chatterji, Sanatan Chattopadhyay, Subhasis Chattopadhyay, Hongfang Chen, Jianping Cheng, V. Chepurnov, S. Chernenko, A. Chernogorov, Kyung-Eon Choi, M.I. Ciobanu, G. Claus, F. Constantin, V. Covlea, M. Csanád, N. D'Ascenzo, S. Das, K. Davkov, V. Davkov, J. de Cuveland, B. Debnath, D. Dementiev, Zhi Deng, H. Deppe, I. Deppner, O. Derenovskaya, C.A. Deveaux, M. Deveaux, K. Dey, M. Dey, P. Dillenseger, V. Dobyrn, D. Doering, A. Dorokhov, A. Drozd, A.K. Dubey, S. Dubnichka, A. Dubnichkova, M. Dürr, W. Dulinski, L. Dutka, M. Dželalija, D. Emschermann, H. Engel, V. Eremin, T. Eşanu, J. Eschke, D. Eschweiler, Jongsik Eum, Huanhuan Fan, O. Fateev, I. Filozova, D. Finogeev, P. Fischer, H. Flemming, U. Frankenfeld, V. Friese, E. Friske, I. Fröhlich, J. Frühauf, Á. Fülöp, J. Gajda, T. Galatyuk, A. Galkin, V. Galkin, G. Gangopadhyay, C. García Chávez, I. Gašparić, J. Gebelein, P. Ghosh, S.K. Ghosh, M. Goffe, L. Golinka-Bezshyyko, V. Golovatyuk, S. Golovnya, V. Golovtsov, M. Golubeva, D. Golubkov, A. Gómez Ramírez, S. Gorbunov, S. Gorokhov, D. Gottschalk, P. Gryboś, A. Grzeszczuk, F. Guber, K. Gudima, A. Gupta, Yu. Gusakov, A. Haldar, S. Haldar, H. Hartmann, J. Hehner, K. Heidel, N. Heine, E. Hellbär, A. Herghelegiu, N. Herrmann, B. Heß, J.M. Heuser, A. Himmi, C. Höhne, R. Holzmann, Guangming Huang, Xinjie Huang, J. Hutsch, D. Hutter, E. Iakovleva, A. Ierusalimov, E.-M. Ilgenfritz, M. Irfan, M. Ivanov, Valery Ivanov, Victor Ivanov, Vladimir Ivanov, A. Ivashkin, K. Jaaskelainen, H. Jahan, V. Jain, V. Jakovlev, T. Janson, A. Jipa, I. Kadenko, B. Kämpfer, S. Kalcher, V. Kalinin, K.-H. Kampert, Tae Im Kang, E. Kaptur, R. Karabowicz, O. Karavichev, T. Karavicheva, D. Karmanov, V. Karnaukhov, E. Karpechev, K. Kasiński, G. Kasprowicz, M. Kaur, A. Kazantsev, U. Kebschull, G. Kekelidze, M.M. Khan, S.A. Khan, A. Khanzadeev, F. Khasanov, A. Khvorostukhin, V. Kirakosyan, M. Kirejczyk, A. Kiryakov, M. Kiš, I. Kisel, P. Kisel, S. Kiselev, A. Kiss, T. Kiss, P. Klaus, R. Kłeczek, Ch. Klein-Bösing, V. Kleipa, P. Kmon, K. Koch, L. Kochenda, P. Koczoń, W. König, M. Kohn, B.W. Kolb, A. Kolosova, B. Komkov, J.M. Kopfer, M. Korolev, I. Korolko, R. Kotte, A. Kotynia, A. Kovalchuk, S. Kowalski, M. Koziel, G. Kozlov, P. Kravtsov, E. Krebs, C. Kreidl, D. Kresan, G. Kretschmar, M. Kretz, M. Krieger, E. Kryshen, W. Kucewicz, L. Kudin, A. Kugler, I. Kulakov, J. Kunkel, A. Kurepin, P. Kurilkin, V. Kushpil, V. Kyva, V. Ladygin, C. Lara, P. Larionov, A. Laso Garcia, E. Lavrik, I. Lazanu, A. Lebedev, S. Lebedev, E. Lebedeva, J. Lehnert, J. Lehrbach, F. Lemke, Cheng Li, Jin Li, Qiyan Li, Yuanjing Li, Yulan Li, V. Lindenstruth, S. Linev, B. Linnik, E. Litvinenko, Feng Liu, I. Lobanov, E. Lobanova, S. Löchner, P.-A. Loizeau, J.A. Lucio Martínez, A. Lymanets, A. Maevskaya, S. Mahajan, D.P. Mahapatra, T. Mahmoud, P. Maj, Z. Majka, A. Malakhov, E. Malankin, D. Malkevich, O. Malyatina, H. Malygina, S. Mandal, V. Manko, S. Manz, V. Marin, A.M. Marin Garcia, J. Markert, S. Masciocchi, T. Matulewicz, M. Merkin, V. Mialkovski, J. Michel, N. Miftakhov, K. Mikhailov, V. Mikhaylov, B. Milanović, V. Militsija, M.F. Mir, D. Miskowiec, T. Morhardt, W.F.J. Müller, C. Müntz, Yu. Murin, R. Najman, L. Naumann, T. Nayak, A. Nedosekin, B. Neumann, W. Niebur, V. Nikulin, D. Normanov, M. Nüssle, A. Oancea, Kunsu Oh, Y. Onishchuk, D. Osipov, G. Ososkov, D. Ossetski, P. Otfinowski, E. Ovcharenko, S. Pal, I. Panasenko, N.R. Panda, S. Parzhitskiy, C. Pauly, Haiping Peng, I. Peric, D. Peshekhonov, V. Peshekhonov, V. Petráček, M. Petriş, A. Petrovici, M. Petrovici, A. Petrovskiy, O. Petukhov, K. Piasecki, J. Pieper, J. Pietraszko, R. Płaneta, E. Plekhanov, V. Plotnikov, V. Plujko, J. Pluta, V. Poliakov, P. Polozov, A. Pop, V. Popov, V. Pospisil, B.V.K.S. Potukuchi, J. Pouryamout, K. Poźniak, A. Prakash, M. Prokudin, I. Pshenichnov, M. Pugach, V. Pugatch, S. Querchfeld, L. Radulescu, S. Raha, W. Raja, F. Rami, R. Raniwala, S. Raniwala, A. Raportirenko, J. Rautenberg, J. Rauza, R. Ray, S. Razin, P. Reichelt, S. Reinecke, A. Reshetin, C. Ristea, O. Ristea, F. Roether, R. Romaniuk, A. Rost, E. Rostchin, I. Rostovtseva, A. Roy, J. Rożynek, Yu. Ryabov, V. Rykalin, A. Sadovsky, S. Sadovsky, R. Sahoo, P.K. Sahu, J. Saini, S. Samanta, S.S. Sambyal, V. Samsonov, J. Sánchez Rosado, S. Sau, V. Saveliev, S. Schatral, C. Schiaua, C.J. Schmidt, H.R. Schmidt, K. Schmidt, K. Schweda, A. Scurtu, F. Seck, S. Seddiki, I. Selyuzhenkov, A. Semennikov, A. Senger, P. Senger, A. Shabunov, Ming Shao, M.K. Sharma, N. Shumeiko, V. Shumikhin, B. Sikora, A. Simakov, C. Simon, C. Simons, R.N. Singaraju, A.K. Singh, B.K. Singh, C.P. Singh, V. Singhal, K. Siwek-Wilczyńska, L. Škoda, I. Skwira-Chalot, I. Som, Jihye Song, I. Sorokin, Z. Sosin, D. Soyk, P. Staszel, A. Stavinskiy, E. Stephan, D. Storozhyk, M. Strikhanov, S. Strohauer, J. Stroth, C. Sturm, R. Sultanov, Yongjie Sun, O. Svoboda, R. Szczygieł, R. Talukdar, Zebo Tang, M. Tanha, J. Tarasiuk, O. Tarassenkova, M.-G. Târzilă, V. Tiflov, T. Tischler, P. Tlustý, A. Toia, T. Tolyhi, N. Topil'skaya, C. Trageser, P. Trivedy, I. Tsakov, Yu. Tsyupa, A. Turowiecki, F. Uhlig, E. Usenko, I. Valin, T. Vasiliev, I. Vassiliev, E. Verbitskaya, W. Verhoeven, A. Veshikov, R. Visinka, Y.P. Viyogi, S. Volkov, Yu. Volkov, A. Vorobiev, A. Voronin, V. Vovchenko, E. Vznuzdaev, M. Vznuzdaev, Dong Wang, Yaping Wang, Wang Yi, C. Wendisch, J.P. Wessels, M. Wiebusch, J. Wiechula, B. Wiedemann, D. Wielanek, A. Wieloch, N. Winckler, M. Winter, K. Wiśniewski, D. Wohlfeld, Gy. Wolf, Won Sanguk, J. Wüstenfeld, Changzhou Xiang, Xu Nu, Jun-Gyu Yi, Zhongbao Yin, In-Kwon Yoo, Qian Yue, B. Yuldashev, I. Yushmanov, W. Zabołotny, Yu. Zaitsev, Yu. Zanevsky, M. Zhalov, Ya Peng Zhang, Yifei Zhang, Daicui Zhou, Xianglei Zhu, A. Zinchenko, W. Zipper, M. Żoładź, P. Zrelov, V. Zryuev, P. Zumbruch, and M. Zyzak

Subjects
Nuclear and High Energy Physics
Published
2014

10. Lifetimes and g-factors of the HFS states in H-like and Li-like bismuth

Author

Johannes Ullmann, J. Vollbrecht, C. Trageser, T. Murböck, Thomas Stöhlker, Matthias Schmidt, Andreas Dax, Rodolfo Sánchez, Kristian König, W. Geithner, J. Meisner, Wilfried Nörtershäuser, B. Maaß, Stefan E. Schmidt, Carsten Brandau, Zoran Andelkovic, M. Hammen, S. Kaufmann, Richard C. Thompson, Matthias Lochmann, Yuri A. Litvinov, Markus Steck, Volker Hannen, Christian Gorges, Christopher Geppert, and Christian Weinheimer

Subjects
IONS, General Physics, Atomic Physics (physics.atom-ph), 0205 Optical Physics, FOS: Physical sciences, chemistry.chemical_element, g-factors, Electron, Physics, Atomic, Molecular & Chemical, HYPERFINE, 01 natural sciences, Physics - Atomic Physics, Ion, Bismuth, 0103 physical sciences, 0307 Theoretical and Computational Chemistry, Physics::Atomic Physics, hyperfine transitions, 010306 general physics, Hyperfine structure, Precision tests of QED, Physics, Science & Technology, 010308 nuclear & particles physics, Optics, Condensed Matter Physics, Atomic and Molecular Physics, and Optics, Magnetic field, chemistry, Physical Sciences, 0202 Atomic, Molecular, Nuclear, Particle and Plasma Physics, lifetimes, Atomic physics, Ground state, highly charged ions, Excitation
Abstract

The LIBELLE experiment performed at the experimental storage ring (ESR) at the GSI Helmholtz Center for Heavy Ion Research in Darmstadt, Germany, has successfully determined the ground state hyperfine (HFS) splittings in hydrogen-like ($^{209}\rm{Bi}^{82+}$) and lithium-like ($^{209}\rm{Bi}^{80+}$) bismuth. The study of HFS transitions in highly charged ions enables precision tests of QED in extreme electric and magnetic fields otherwise not attainable in laboratory experiments. Besides the transition wavelengths the time resolved detection of fluorescence photons following the excitation of the ions by a pulsed laser system also allows to extract lifetimes of the upper HFS levels and g-factors of the bound 1s and 2s electrons for both charge states. While the lifetime of the upper HFS state in $^{209}\rm{Bi}^{82+}$ has already been measured in earlier experiments, an experimental value for lifetime of this state in $^{209}\rm{Bi}^{80+}$ is reported for the first time in this work., Comment: 14 pages, 6 figures

Published
2019

11. The CBM Collaboration

Author

A. Abuhoza, J. Adamczewski-Musch, M.M. Aggarwal, Z. Ahammed, F. Ahmad, N. Ahmad, S. Ahmad, A. Akindinov, P. Akishin, E. Akishina, T. Akishina, V. Akishina, M. Al-Turany, S. Amar-Youcef, M. Anđelić, C. Andrei, A. Andronic, Yu. Anisimov, H. Appelshäuser, A. Arend, D. Argintaru, T. Armbruster, E. Atkin, S. Avdeyev, M.D. Azmi, V. Baban, M. Bach, E. Badura, S. Baginyan, T. Balog, S. Bandyopadhyay, P. Banerjee, N. Baranova, D. Bartoş, S. Bashir, Z. Basrak, M. Baszczyk, O. Batenkov, V. Baublis, C. Baumann, K.-H. Becker, T. Bel, S. Belogurov, I. Berceanu, E. Berdermann, A. Berdnikov, Y. Berdnikov, R. Berendes, C. Bergmann, D. Bertini, C. Beşliu, O. Bezshyyko, P.P. Bhaduri, A. Bhasin, A.K. Bhati, B. Bhattacharjee, A. Bhattacharyya, T.K. Bhattacharyya, S. Biswas, D. Blau, C. Blume, Yu. Bocharov, S. Böttger, M. Borysova, B. Bozsogi, T. Breitner, U. Brüning, J. Brzychczyk, A. Bubak, A. Bychkov, Xu Cai, M. Cãlin, R. Čaplar, G. Caragheorgheopol, I. Carević, V. Cătănescu, A. Chakrabarti, S. Chatterji, Sanatan Chattopadhyay, Subhasis Chattopadhyay, Hongfang Chen, Jianping Cheng, V. Chepurnov, S. Chernenko, A. Chernogorov, M.I. Ciobanu, G. Claus, F. Constantin, V. Covlea, M. Csanád, N. DʼAscenzo, S. Das, K. Davkov, V. Davkov, J. de Cuveland, B. Debnath, Zhi Deng, H. Deppe, I. Deppner, O. Derenovskaya, M. Deveaux, K. Dey, M. Dey, P. Dillenseger, V. Dobyrn, D. Doering, M. Domachowski, A. Dorokhov, C.A. Dritsa, A.K. Dubey, S. Dubnichka, A. Dubnichkova, W. Dulinski, M. Dželalija, D. Emschermann, H. Engel, V. Eremin, T. Eşanu, J. Eschke, O. Fateev, P. Fischer, H. Flemming, U. Frankenfeld, V. Friese, I. Fröhlich, J. Frühauf, Á. Fülöp, J. Gajda, T. Galatyuk, A. Galkin, V. Galkin, G. Gangopadhyay, M.S. Ganti, C. García Chávez, I. Gašparić, J. Gebelein, P. Ghosh, S.K. Ghosh, M. Goffe, V. Golovatyuk, S. Golovnya, V. Golovtsov, M. Golubeva, D. Golubkov, S. Gorbunov, D. Gottschalk, P. Gryboś, A. Grzeszczuk, F. Guber, A. Gupta, Yu. Gusakov, A. Haldar, S. Haldar, M. Hartig, J. Hehner, K. Heidel, N. Heine, A. Herghelegiu, N. Herrmann, B. Heß, J.M. Heuser, A. Himmi, C. Höhne, R. Holzmann, Guangming Huang, J. Hutsch, D. Hutter, A. Ierusalimov, E.-M. Ilgenfritz, M. Irfan, Valery Ivanov, Victor Ivanov, Vladimir Ivanov, A. Ivashkin, K. Jaaskelainen, V. Jakovlev, T. Janson, A. Jipa, I. Kadenko, B. Kämpfer, S. Kalcher, V. Kalinin, K.-H. Kampert, Tae Im Kang, E. Kaptur, R. Karabowicz, O. Karavichev, T. Karavicheva, D. Karmanov, V. Karnaukhov, E. Karpechev, K. Kasiński, M. Kaur, A. Kazantsev, U. Kebschull, G. Kekelidze, M.M. Khan, S.A. Khan, A. Khanzadeev, F. Khasanov, V. Kirakosyan, M. Kirejczyk, M. Kiš, I. Kisel, P. Kisel, S. Kiselev, A. Kiss, T. Kiss, R. Kłeczek, Ch. Klein-Bösing, V. Kleipa, K. Koch, L. Kochenda, P. Koczoń, B. Kolb, B. Komkov, J.M. Kopfer, M. Korolev, I. Korolko, R. Kotte, A. Kotynia, A. Kovalchuk, S. Kowalski, M. Koziel, G. Kozlov, P. Kravtsov, C. Kreidl, D. Kresan, M. Kretz, M. Krieger, E. Kryshen, W. Kucewicz, L. Kudin, A. Kugler, I. Kulakov, J. Kunkel, A. Kurepin, V. Kyva, V. Ladygin, C. Lara, P. Larionov, A. Laso Garcia, E. Lavrik, I. Lazanu, A. Lebedev, S. Lebedev, E. Lebedeva, J. Lehrbach, F. Lemke, Cheng Li, Jin Li, Li Qyian, Yuanjing Li, Yulan Li, V. Lindenstruth, S. Linev, E. Litvinenko, Feng Liu, I. Lobanov, E. Lobanova, S. Löchner, P.-A. Loizeau, A. Lymanets, A. Maevskaya, S. Mahajan, D.P. Mahapatra, T. Mahmoud, P. Maj, Z. Majka, A. Malakhov, O. Malyatina, H. Malygina, J. Manjavidze, V. Manko, S. Manz, V. Marin, T. Matulewicz, M. Merkin, V. Mialkovski, N. Miftakhov, K. Mikhailov, B. Milanovic, V. Militsija, F. Mir, W.F.J. Müller, C. Müntz, Yu. Murin, L. Naumann, T. Nayak, B. Neumann, W. Niebur, V. Nikulin, M. Nüssle, A. Oancea, Oh Kunsu, Y. Onishchuk, G. Ososkov, D. Ossetski, P. Otfinowski, E. Ovcharenko, Pal Susanta, I. Panasenko, S. Parzhitskiy, C. Pauly, Haiping Peng, I. Peric, D. Peshekhonov, V. Peshekhonov, V. Petráček, M. Petriş, A. Petrovici, M. Petrovici, A. Petrovskiy, O. Petukhov, K. Piasecki, J. Pietraszko, E. Plekhanov, V. Plujko, V. Poliakov, P. Polozov, A. Pop, V. Popov, V. Pospisil, B.V.K.S. Potukuchi, J. Pouryamout, A. Prakash, M. Prokudin, I. Pshenichnov, V. Pugatch, S. Querchfeld, S. Raha, W. Raja, F. Rami, R. Raniwala, S. Raniwala, A. Raportirenko, J. Rautenberg, R. Ray, S. Razin, P. Reichelt, S. Reinecke, A. Reshetin, C. Ristea, O. Ristea, E. Rostchin, I. Rostovtseva, A. Roy, J. Rożynek, Yu. Ryabov, V. Rykalin, A. Sadovsky, S. Sadovsky, P.K. Sahu, J. Saini, S.S. Sambyal, V. Samsonov, J. Sanchez Rosado, V. Saveliev, S. Schatral, C. Schiaua, C.J. Schmidt, H.R. Schmidt, C. Schrader, K. Schweda, A. Scurtu, S. Seddiki, A. Semennikov, A. Senger, P. Senger, A. Shabunov, Ming Shao, M.K. Sharma, V. Shumikhin, B. Sikora, A. Simakov, C. Simon, C. Simons, R.N. Singaraju, A.K. Singh, B.K. Singh, C.P. Singh, V. Singhal, M. Singla, K. Siwek-Wilczynska, L. Škoda, Song Jihye, I. Sorokin, D. Soyk, P. Staszel, A. Stavinskiy, E. Stephan, D. Storozhyk, M. Strikhanov, J. Stroth, C. Sturm, Yongjie Sun, O. Svoboda, R. Szczygieł, R. Talukdar, Zebo Tang, O. Tarassenkova, M. Târzilă, V. Tiflov, T. Tischler, P. Tlustý, T. Tolyhi, N. Topilʼskaya, C. Trageser, P. Trivedy, I. Tsakov, Yu. Tsyupa, F. Uhlig, E. Usenko, I. Valin, T. Vasiliev, I. Vassiliev, E. Verbitskaya, W. Verhoeven, A. Veshikov, Y. Viyogi, S. Volkov, Yu. Volkov, A. Vorobiev, A. Voronin, E. Vznuzdaev, M. Vznuzdaev, Dong Wang, Yaping Wang, Yi Wang, C. Wendisch, J.P. Wessels, J. Wiechula, B. Wiedemann, M. Winter, K. Wisniewski, D. Wohlfeld, Gy. Wolf, J. Wüstenfeld, Changzhou Xiang, Xu Nu, Jun-Gyu Yi, Yin Zhongbao, In-Kwon Yoo, Qian Yue, I. Yushmanov, Yu. Zaitsev, Yu. Zanevsky, M. Zhalov, Ya Peng Zhang, Yifei Zhang, Zhou Daicui, Xianglei Zhu, A. Zinchenko, W. Zipper, M. Żoładź, P. Zrelov, V. Zryuev, P. Zumbruch, and M. Zyzak

Subjects
Nuclear and High Energy Physics
Published
2013

12. Impact parameter sensitive study of inner-shell atomic processes in the experimental storage ring

Author

Yu. A. Litvinov, C. Kozhuharov, Oliver Forstner, K. H. Blumenhagen, Ashok Kumar, Xiao-Lin Tu, Y. S. Kozhedub, U. Spillmann, Paul Indelicato, N. Petridis, C. Brandau, Michael Lestinsky, T. Gassner, Wanqiu Chen, S. Hagmann, R. T. Zhang, P. M. Hillenbrand, C. Trageser, D. Schury, Martino Trassinelli, A. Gumberidze, A. Bräuning-Demian, Th. Stöhlker, S. Trotsenko, H Beyer, Robert E. Grisenti, Bingshui Gao, Robert D. DuBois, Institut des Nanosciences de Paris (INSP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Kastler Brossel (LKB [Collège de France]), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Collège de France (CdF (institution)), GSI Helmholtzzentrum für Schwerionenforschung (GSI), Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Collège de France (CdF (institution))-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Dariusz Banaś, and Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris)-Collège de France (CdF)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Nuclear and High Energy Physics, Work (thermodynamics), chemistry.chemical_element, Ion-atom collisions, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Ion, 99-00, Xenon, 0103 physical sciences, X-rays, Physics::Atomic and Molecular Clusters, 2010 MSC: 00-01, 99-00, 010306 general physics, Nuclear Experiment, Instrumentation, Range (particle radiation), Pilot experiment, 010308 nuclear & particles physics, Projectile, Chemistry, 00-01, Atomic physics, Impact parameter, Storage ring
Abstract

International audience; 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.

Published
2016

13. Encoding of Stimulus Frequency and Sensor Motion in the Posterior Medial Thalamic Nucleus

Author

Tatiana Bezdudnaya, Jason C. Trageser, Asaf Keller, and Radi Masri

Subjects
animal structures, Physiology, Midline Thalamic Nuclei, Action Potentials, Sensory system, Stimulation, Rats, Sprague-Dawley, Motion, Trigeminal ganglion, Reaction Time, medicine, Animals, Wakefulness, Neurons, Afferent Pathways, Electromyography, Chemistry, General Neuroscience, Whisking in animals, Dose-Response Relationship, Radiation, Articles, Electric Stimulation, Rats, Cortex (botany), medicine.anatomical_structure, Vibrissae, Female, sense organs, Neuroscience, Nucleus, Reticular activating system
Abstract

In all sensory systems, information is processed along several parallel streams. In the vibrissa-to-barrel cortex system, these include the lemniscal system and the lesser-known paralemniscal system. The posterior medial nucleus (POm) is the thalamic structure associated with the latter pathway. Previous studies suggested that POm response latencies are positively correlated with stimulation frequency and negatively correlated with response duration, providing a basis for a phase locked loop-temporal decoding of stimulus frequency. We tested this hypothesis by analyzing response latencies of POm neurons, in both awake and anesthetized rats, to vibrissae deflections at frequencies between 0.3 and 11 Hz. We found no significant, systematic correlation between stimulation frequency and the latency or duration of POm responses. We obtained similar findings from recording in awake rats, in rats under different anesthetics, and in anesthetized rats in which the reticular activating system was stimulated. These findings suggest that stimulus frequency is not reliably reflected in response latency of POm neurons. We also tested the hypothesis that POm neurons respond preferentially to sensor motion, that is, they respond to whisking in air, without contacts. We recorded from awake, head-restrained rats while monitoring vibrissae movements. All POm neurons responded to passive whisker deflections, but none responded to noncontact whisking. Thus like their counterparts in the trigeminal ganglion, POm neurons may not reliably encode whisking kinematics. These observations suggest that POm neurons might not faithfully encode vibrissae inputs to provide reliable information on vibrissae movements or contacts.

Published
2008

14. Between atomic and nuclear physics: radioactive decays of highly-charged ions

Author

Christophor Kozhuharov, Takuji Izumikawa, Takashi Ohtsubo, Markus Steck, Yuhu Zhang, Helmut Weick, D. H. Schneider, Fritz Bosch, Yuri A. Litvinov, Bao-Hua Sun, Thomas Faestermann, G. Münzenberg, F. Nolden, Takayuki Yamaguchi, Philip M Walker, C. Brandau, Meng Wang, Xiang-Cheng Chen, Klaus Blaum, Rene Reifarth, Toshio Suzuki, Nicolas Winckler, Akira Ozawa, Sergey Litvinov, Hu-Shan Xu, S. Hagmann, M. S. Sanjari, Xinwen Ma, Xiao-Lin Tu, Bingshui Gao, M. A. Najafi, Pierre-Michel Hillenbrand, Paul Bühler, Tomohiro Uesaka, Philip Woods, Matthew Reed, Dinko Atanasov, Iris Dillmann, H. Geissel, F. Suzaki, Thomas Stöhlker, C. Trageser, Xin-Liang Yan, Jan Kurcewicz, Zygmunt Patyk, Roman Gernhäuser, and F. C. Ozturk

Subjects
Physics, Nuclear physics, Stellar nucleosynthesis, Isochronous mass spectrometry, Electron shell, Electron, Atomic physics, Präzisionsexperimente - Abteilung Blaum, Condensed Matter Physics, Atomic and Molecular Physics, and Optics, Computer Science::Databases, Ion
Abstract

Highly charged radioactive ions can be stored for extended periods of time in storage rings which allows for precision measurements of their decay modes. The straightforward motivation for performing such studies is that fully ionised nuclei or few-electron ions can be viewed as clean quantum-mechanical systems, in which the interactions of the many electrons can be either excluded or treated precisely. Thus, the influence of the electron shell on the decay probability can be investigated. Another important motivation is stellar nucleosynthesis, which proceeds at high temperatures and the involved atoms are therefore highly ionised. Presented here is a compact review of the relevant experiments conducted at heavy-ion storage rings. Furthermore, we outline the perspectives for future experiments at new-generation storage-ring facilities.

Published
2015

15. Cholinergic Regulation of the Posterior Medial Thalamic Nucleus

Author

Radi Masri, Tatiana Bezdudnaya, Ying Li, Jason C. Trageser, and Asaf Keller

Subjects
animal structures, Tegmentum Mesencephali, Physiology, Thalamus, Muscarinic Agonists, Biology, Receptors, Presynaptic, Somatosensory system, Urethane, Article, gamma-Aminobutyric acid, Rats, Sprague-Dawley, Parasympathetic nervous system, Parasympathetic Nervous System, medicine, Animals, Anesthesia, gamma-Aminobutyric Acid, Ventral Thalamic Nuclei, General Neuroscience, Iontophoresis, Electric Stimulation, Rats, Fentanyl, medicine.anatomical_structure, Data Interpretation, Statistical, Vibrissae, GABAergic, Zona incerta, Cholinergic, Carbachol, Female, sense organs, Extracellular Space, Halothane, Nucleus, Neuroscience, Adjuvants, Anesthesia, medicine.drug
Abstract

We previously showed that the GABAergic nucleus zona incerta (ZI) suppresses vibrissae-evoked responses in the posterior medial (POm) thalamus of the rodent somatosensory system. We proposed that this inhibitory incertothalamic pathway regulates POm responses during different behavioral states. Here we tested the hypothesis that this pathway is modulated by the ascending brain stem cholinergic system, which regulates sleep–wake cycles and states of vigilance. We demonstrate that cholinergic inputs facilitate POm responses to vibrissae stimulation. Activation of the cholinergic system by stimulation of brain stem cholinergic nuclei (laterodorsal tegmental and the pedunculopontine tegmental) or by tail pinch significantly increased the magnitude of POm responses to vibrissae stimulation. Microiontophoresis of the muscarinic receptor agonist carbachol enhanced POm responses to vibrissae stimulation. Application of carbachol to an in vitro slice preparation reduced the frequency but not the amplitude of miniature inhibitory postsynaptic currents, indicating a presynaptic site of action for carbachol. We conclude that the cholinergic system facilitates POm responses by suppressing GABAergic inputs from ZI. We propose the state-dependent gating hypothesis, which asserts that differing behavioral states, regulated by the brain stem cholinergic system, modulate the flow of information through POm.

Published
2006

16. State-Dependent Gating of Sensory Inputs by Zona Incerta

Author

Jason C. Trageser, Larisa Sellers, Asaf Keller, Kathryn A. Burke, Radi Masri, and Ying Li

Subjects
Patch-Clamp Techniques, animal structures, Carbachol, Physiology, Thalamus, Gating, In Vitro Techniques, Article, Rats, Sprague-Dawley, medicine, Animals, Neurons, Afferent, gamma-Aminobutyric Acid, Brain Mapping, biology, Chemistry, General Neuroscience, Subthalamus, Electric Stimulation, Rats, medicine.anatomical_structure, nervous system, biology.protein, Zona incerta, Cholinergic, Female, Neuroscience, Reticular activating system, Parvalbumin, medicine.drug
Abstract

We have previously shown that the GABAergic nucleus zona incerta (ZI) suppresses vibrissae-evoked responses in the posterior medial (POm) thalamus of the rodent somatosensory system. We proposed that this inhibitory incerto-thalamic pathway regulates POm responses during different behavioral states. Here we tested the hypothesis that the cholinergic reticular activating system, implicated in regulating states of arousal, modulates ZI activity. We show that stimulation of brain stem cholinergic nuclei (laterodorsal tegmental and pedunculopontine tegmental) results in suppression of spontaneous firing of ZI neurons. Iontophoretic application of the cholinergic agonist carbachol to ZI neurons suppresses both their spontaneous firing and their vibrissae-evoked responses. We also found that carbachol application to an in vitro slice preparation suppresses spontaneous firing of neurons in the ventral sector of ZI (ZIv). Finally, we demonstrate that the majority of ZIv neurons contain parvalbumin and project to POm. Based on these results, we present the state-dependent gating hypothesis, which states that differing behavioral states—regulated by the brain stem cholinergic system—modulate ZI activity, thereby regulating the response properties of higher-order nuclei such as POm.

Published
2006

17. Proton and α capture studies for nuclear astrophysics at GSI storage rings

Author

B. Löher, F. Nolden, X. Chen, C. Trageser, U. Popp, Michael Lestinsky, R. Hess, C. Wolf, Mario Weigand, N. Petridis, S. Sanjari, G. J. Lane, P. M. Hillenbrand, P. Erbacher, Sergey Litvinov, Kathrin Göbel, A. Gumberidze, Matthew Reed, Gyuri Gyürky, Jan Glorius, S. Fiebiger, H. Törnqvist, C. Brandau, Rene Reifarth, Thomas Davinson, B. Thomas, Herbert A. Simon, M. Träger, Christoph Langer, U. Spillmann, M. Volknandt, Claudia Lederer-Woods, C. Kozhuharov, Deniz Kurtulgil, Ole Hinrichs, Thomas Stöhlker, Sergiy Trotsenko, S. Torilov, B. Brückner, M. Steck, Tamás Szücs, Y. Litvinov, Z. Slavkovská, Philip Woods, Matthias Heil, B. Jurado, and T. Gassner

Subjects
Physics, History, Proton, 010308 nuclear & particles physics, 7. Clean energy, 01 natural sciences, Computer Science Applications, Education, Ion, Nuclear physics, 0103 physical sciences, Nuclear astrophysics, Physics::Accelerator Physics, ddc:530, Atomic physics, Nuclear Experiment, 010303 astronomy & astrophysics, Beam (structure)
Abstract

The 124Xe(p,γ) reaction has been measured for the first time at energies around the Gamow window by using stored ions at the ESR facility. The desired beam energies below 10 MeV/u introduce new experimental challenges like windowless ions detection under UHV conditions, extremely short beam lifetimes and efficient beam deceleration and cooling, all of which have been successfully met.

Published
2017

18. Reply to Ahissar et al

Author

Tatiana Bezdudnaya, Asaf Keller, Jason C. Trageser, and Radi Masri

Subjects
Physiology, General Neuroscience, Whisking in animals, Thalamic nucleus, Response Duration, Letters to the Editor, Psychology, Neuroscience
Abstract

reply: We are grateful for the comments by Ahissar et al. on our recent manuscript (Masri et al. 2008) and for the opportunity to respond to these comments. Our manuscript focused on testing the hypothesis—formulated by Ahissar and collaborators—that the paralemniscal pathway in the rat's vibrissae system functions as a phase-locked loop (PLL) (Ahissar et al. 2000; Sosnik et al. 2001). We emphasize that we do not question the validity of their experimental results or of their analyses. Rather, our goal was to critically test their hypothesis that this sensory system makes use of a PLL mechanism. Two critical predictions emerge from this hypothesis: 1) response latency of neurons in the posteromedial thalamic nucleus (POm) correlates positively with whisking frequency and 2) response duration of these neurons correlates negatively with whisking frequency. In our manuscript we demonstrated that neither of these predictions holds true.

Published
2008

19. A perceptual representation in the frontal eye field during covert visual search that is more reliable than the behavioral report

Author

Kirk G. Thompson, Jason C. Trageser, Ilya E. Monosov, and Yifeng Zhou

Subjects
Visual perception, genetic structures, Eye Movements, media_common.quotation_subject, Sensory system, Fixation, Ocular, Stimulus (physiology), Choice Behavior, Article, Perception, Animals, media_common, Visual search, Neurons, Communication, Behavior, Animal, business.industry, General Neuroscience, Eye movement, Gaze, Macaca mulatta, ROC Curve, Covert, Visual Perception, Visual Fields, Psychology, business, Cognitive psychology
Abstract

Neuronal activity in the frontal eye field (FEF) identifies locations of behaviorally important objects for guiding attention and eye movements. We recorded neural activity in the FEF of monkeys trained to manually turn a lever towards the location of a pop-out target of a visual search array without shifting gaze. We examined whether the reliability of the neural representation of the salient target location predicted the monkeys’ accuracy of reporting target location. We found that FEF neurons reliably encoded the location of the target stimulus not only on correct trials but also on error trials. The representation of target location in FEF persisted until the manual behavioral report but did not increase in magnitude. This result suggests that, in the absence of an eye movement report, FEF encodes the perceptual information necessary to perform the task but does not accumulate this sensory evidence towards a perceptual decision threshold. These results provide physiological evidence that, under certain circumstances, accurate perceptual representations do not always lead to accurate behavioral reports and that variability in processes outside of perception must be considered to account for the variability in perceptual choice behavior.

Published
2008

20. A continuous, broadband data acquisition for Schottky signals in atomic and nuclear physics experiments at heavy-ion storage rings

Author

Yu. A. Litvinov, Ch. Kozhuharov, Th. Stöhlker, Alfred Müller, C. Brandau, F. Nolden, S. Sanjari, and C. Trageser

Subjects
Physics, Nuclear physics, History, Data acquisition, Ion beam, Schottky diode, Mass spectrometry, Storage ring, Noise (radio), Atomic mass, Computer Science Applications, Education, Ion
Abstract

At heavy-ion storage rings Schottky noise techniques belong to the established non-destructive diagnostics methods. In addition, Schottky mass spectrometry is used to observe atomic masses and nuclear decays down to the level of a single stored ion without destruction of the circulating ion beam. In this contribution a new broadband, continuous data acquisition for Schottky signals and first experimental results obtained with this system during several commissioning runs at the storage ring ESR, Darmstadt are presented. Special emphasis will be given to present and future applications in atomic and nuclear physics experiments at storage rings.

Published
2015

21. Reducing the Uncertainty: Gating of Peripheral Inputs by Zona Incerta

Author

Jason C. Trageser and Asaf Keller

Subjects
animal structures, Population, Sensory system, Somatosensory system, Article, Rats, Sprague-Dawley, Evoked Potentials, Somatosensory, medicine, Animals, Neurons, Afferent, education, education.field_of_study, Afferent Pathways, Neocortex, General Neuroscience, Subthalamus, Neural Inhibition, Posterior Thalamic Nuclei, Rats, Subthalamic nucleus, medicine.anatomical_structure, Vibrissae, Zona incerta, Female, Psychology, Neuroscience
Abstract

Sensory inputs are relayed to the neocortex by “first-order” thalamic nuclei, the responses of which are determined by ascending inputs from peripheral receptors. In contrast, “higher-order” thalamic nuclei respond poorly to peripheral inputs, and their responses are thought to be determined by descending cortical inputs. We tested this hypothesis by recording from neurons in the higher-order somatosensory posterior medial (POm) nucleus of narcotized rats. As reported previously, POm neurons responded to whisker stimuli with long-latency (median, 27 msec) and low-magnitude responses, consistent with cortically driven responses. However, when we suppressed inhibitory inputs from the subthalamic nucleus zona incerta (ZI), POm responses were of significantly higher magnitude and shorter latency, with many POm neurons responding at latencies consistent with ascending driving inputs from trigeminal nuclei. Our data suggest that POm comprises two neuronal populations: one population is driven by both peripheral and cortical inputs, and the second population responds only to cortical inputs. These findings demonstrate that ZI gates peripheral inputs to POm, enabling it to function both as a first-order and higher-order nucleus. Because ZI innervates all higher-order nuclei, this gating mechanism may exert similar regulation of thalamic processing in other sensory systems.

Published
2004

22. Precise temporal responses in whisker trigeminal neurons

Author

Soo Hyun Lee, Asaf Keller, Daniel J. Simons, Lauren M. Jones, and Jason C. Trageser

Subjects
Trigeminal nerve, Tactile discrimination, integumentary system, Physiology, General Neuroscience, Action Potentials, Stimulus (physiology), Afferent Neurons, Article, Rats, Trigeminal ganglion, Vibrissae, Reaction Time, Animals, Female, Trigeminal Nerve, Robust coding, Psychology, Neuroscience
Abstract

The ability of rats using their whiskers to perform fine tactile discrimination rivals that of humans using their fingertips. Rats must perform these discriminations rapidly and accurately while palpating the environment with their whiskers. This suggests that whisker-derived inputs produce a robust and reliable code, capable of capturing complex, high-frequency information. The first neural representation of whisker-derived stimulus information is in primary afferent neurons of the trigeminal ganglion. Here we demonstrate that there is a continuum of direction-dependent response profiles in trigeminal neurons and provide the first quantitative analysis of the encoding of complex stimuli by these neurons. We show that all classes of trigeminal ganglion neurons respond with highly reproducible temporal spike patterns to transient stimuli. Such a robust coding mechanism may allow rapid perception of complex tactile features.

Published
2004

23. Molecular genetic studies in lymphocyte apoptosis and human autoimmunity

Author

D A, Martin, B, Combadiere, F, Hornung, D, Jiang, H, McFarland, R, Siegel, C, Trageser, J, Wang, L, Zheng, and M J, Lenardo

Subjects
Fas-Associated Death Domain Protein, Humans, Apoptosis, Lymphocytes, Syndrome, fas Receptor, Carrier Proteins, Lymphoproliferative Disorders, Adaptor Proteins, Signal Transducing, Autoimmune Diseases, Protein Binding
Abstract

Using a genetic approach, we have studied the molecular basis of human autoimmunity with special emphasis on a disease that is due to defective lymphocyte apoptosis. Recently, we and our collaborators have found that the autoimmune/lymphoproliferative syndrome (ALPS), an inherited disease of children comprising marked lymphoid hyperplasia and autoimmune manifestations, is due to abnormalities in the CD95 gene that cause defective lymphocyte apoptosis. Our recent investigations have shown that the mutations in most families with ALPS cause either global or local changes in the structure of a cytoplasmic portion of the molecule called the 'death domain'. These death domain alterations impair binding of the adapter protein FADD/MORT1 and result in a failure to activate apoptotic caspases after CD95 (Fas/APO-1) cross-linking. Mutations in apoptotic caspases may also contribute to the pathogenesis of ALPS in individuals that have no CD95 gene mutations.

Published
1998

24. Radiation tolerance of a column parallel CMOS sensor with high resistivity epitaxial layer

Author

A. Himmi, F. M. Wagner, Michael Deveaux, Frédéric Morel, C. Müntz, M. Specht, C. Santos, W. Dulinski, C. Colledani, C. Trageser, M. Gelin, Christine Hu-Guo, G. Doziere, Andrei Dorokhov, M. Goffe, Gilles Claus, N. Chon-Sen, Marc Winter, J. Baudot, R. De Masi, Michal Koziel, K. Jaaskelainen, I. Valin, I. Fröhlich, Joachim Stroth, D. Doering, and C. Schrader

Subjects
Physics, CMOS sensor, Pixel, Physics::Instrumentation and Detectors, business.industry, Radiation, Tracking (particle physics), Charged particle, Optics, CMOS, Particle, Optoelectronics, business, Instrumentation, Mathematical Physics, Order of magnitude
Abstract

CMOS Monolithic Active Pixel Sensors (MAPS) demonstrate excellent performances in the field of charged particle tracking. A single point resolution of 1–2 μm and a detection efficiency close to 100% were routinely observed with various MAPS designs featuring up to 106 pixels on active areas as large as 4 cm2[1]. Those features make MAPS an interesting technology for vertex detectors in particle and heavy ion physics. In order to adapt the sensors to the high particle fluxes expected in this application, we designed a sensor with fast column parallel readout and partially depleted active volume. The latter feature was expected to increase the tolerance of the sensors to non-ionizing radiation by one order of magnitude with respect to the standard technology. This paper discusses the novel sensor and presents the results on its radiation tolerance.

Published
2011

25. Measurements of Simultaneously Recorded Spiking Activity and Local Field Potentials Suggest that Spatial Selection Emerges in the Frontal Eye Field

Author

Ilya E. Monosov, Kirk G. Thompson, and Jason C. Trageser

Subjects
Male, Visual perception, Eye Movements, genetic structures, Photic Stimulation, Neuroscience(all), Action Potentials, Local field potential, Article, Reaction Time, Humans, Animals, Visual Cortex, Visual search, Communication, business.industry, General Neuroscience, Eye movement, Macaca mulatta, Field (geography), eye diseases, body regions, Research Design, Space Perception, Saccade, Time course, Visual Perception, Visual Fields, business, Psychology, SYSNEURO, Neuroscience, Psychomotor Performance
Abstract

SummaryThe frontal eye field (FEF) participates in selecting the location of behaviorally relevant stimuli for guiding attention and eye movements. We simultaneously recorded local field potentials (LFPs) and spiking activity in the FEF of monkeys performing memory-guided saccade and covert visual search tasks. We compared visual latencies and the time course of spatially selective responses in LFPs and spiking activity. Consistent with the view that LFPs represent synaptic input, visual responses appeared first in the LFPs followed by visual responses in the spiking activity. However, spatially selective activity identifying the location of the target in the visual search array appeared in the spikes about 30 ms before it appeared in the LFPs. Because LFPs reflect dendritic input and spikes measure neuronal output in a local brain region, this temporal relationship suggests that spatial selection necessary for attention and eye movements is computed locally in FEF from spatially nonselective inputs.

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26. 4-[125I] iodophenyltrimethylammonium ion, an iodinated acetylcholinesterase inhibitor with potential as a myocardial imaging agent

Author

H D, Burns, L G, Marzilli, R F, Dannals, T E, Dannals, T C, Trageser, P, Conti, and H N, Wagner

Subjects
Iodine Radioisotopes, Quaternary Ammonium Compounds, Mice, Isotope Labeling, Animals, Heart, Tissue Distribution, Cholinesterase Inhibitors, Radionuclide Imaging, Half-Life
Abstract

4-[125I]Iodophenyltrimethylammonium acetate (4-I-125 PTMA) was prepared by chloramine-T iodination of N,N-dimethylaniline and subsequent methylation with methyliodide. Purification by thin layer chromatography afforded a product whose specific activity approached the theoretical carrier-free level. Biodistribution studies in normal ICR mice showed a significant accumulation of 4-I-125 PTMA in the heart tissue, with heart-to-blood ratios of 12.5, 10.4, 7.8, 3.4, 3.4, and 3.3 at 1, 5, 10, 30, 60, and 120 min, respectively. Initial uptake in the heart was greater than 26% of the injected dose per gram. Twenty-five percent of the activity was excreted unchanged by the kidneys during the first 5 min. Less than half of the injected activity was retained in mice at 120 min.

Published
1980

27. Radiolabeled benzoylcholine derivatives as possible myocardial-imaging agents

Author

H. D. Burns, Luigi G. Marzilli, T. C. Trageser, Henry N. Wagner, and Robert F. Dannals

Subjects
chemistry.chemical_classification, Sodium, Iodide, Radiochemistry, Pharmaceutical Science, chemistry.chemical_element, Heart, Iodine, Medicinal chemistry, Choline, Iodine Radioisotopes, chemistry.chemical_compound, Mice, Benzoylcholine, chemistry, In vivo, Isotope Labeling, Nucleophilic substitution, Animals, Tissue Distribution, Radionuclide Imaging, Methyl iodide
Abstract

Two radioiodinated analogs of benzoylcholine were investigated as possible myocardial-imaging agents. O-([2-125I]iodobenzoyl)choline and N-([2-125I]iodobenzoyl)cholamine were prepared by nucleophilic substitution of sodium [125I] iodide for stable iodine in O-(N,N-dimethylaminoethyl)-2-iodobenzoate and N-(N', N'-dimethyiaminoethyl)-2-iodobenzamide, respectively, and by methylation with methyl iodide. The in vivo distribution of each compound in mice was determined as a function of time. Favorable heart-to-blood and heart-to-lung ratios were obtained with N-([2-125I]iodobenzoyl)cholamine.

Published
1981

29. Approaching the Gamow Window with Stored Ions: Direct Measurement of ^{124}Xe(p,γ) in the ESR Storage Ring.

Author

Glorius J, Langer C, Slavkovská Z, Bott L, Brandau C, Brückner B, Blaum K, Chen X, Dababneh S, Davinson T, Erbacher P, Fiebiger S, Gaßner T, Göbel K, Groothuis M, Gumberidze A, Gyürky G, Heil M, Hess R, Hensch R, Hillmann P, Hillenbrand PM, Hinrichs O, Jurado B, Kausch T, Khodaparast A, Kisselbach T, Klapper N, Kozhuharov C, Kurtulgil D, Lane G, Lederer-Woods C, Lestinsky M, Litvinov S, Litvinov YA, Löher B, Nolden F, Petridis N, Popp U, Rauscher T, Reed M, Reifarth R, Sanjari MS, Savran D, Simon H, Spillmann U, Steck M, Stöhlker T, Stumm J, Surzhykov A, Szücs T, Nguyen TT, Taremi Zadeh A, Thomas B, Torilov SY, Törnqvist H, Träger M, Trageser C, Trotsenko S, Varga L, Volknandt M, Weick H, Weigand M, Wolf C, Woods PJ, and Xing YM

Abstract

We report the first measurement of low-energy proton-capture cross sections of ^{124}Xe in a heavy-ion storage ring. ^{124}Xe^{54+} ions of five different beam energies between 5.5 and 8 AMeV were stored to collide with a windowless hydrogen target. The ^{125}Cs reaction products were directly detected. The interaction energies are located on the high energy tail of the Gamow window for hot, explosive scenarios such as supernovae and x-ray binaries. The results serve as an important test of predicted astrophysical reaction rates in this mass range. Good agreement in the prediction of the astrophysically important proton width at low energy is found, with only a 30% difference between measurement and theory. Larger deviations are found above the neutron emission threshold, where also neutron and γ widths significantly impact the cross sections. The newly established experimental method is a very powerful tool to investigate nuclear reactions on rare ion beams at low center-of-mass energies.

Published
2019
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30. High precision hyperfine measurements in Bismuth challenge bound-state strong-field QED.

Author

Ullmann J, Andelkovic Z, Brandau C, Dax A, Geithner W, Geppert C, Gorges C, Hammen M, Hannen V, Kaufmann S, König K, Litvinov YA, Lochmann M, Maaß B, Meisner J, Murböck T, Sánchez R, Schmidt M, Schmidt S, Steck M, Stöhlker T, Thompson RC, Trageser C, Vollbrecht J, Weinheimer C, and Nörtershäuser W

Abstract

Electrons bound in highly charged heavy ions such as hydrogen-like bismuth 209 Bi 82+ experience electromagnetic fields that are a million times stronger than in light atoms. Measuring the wavelength of light emitted and absorbed by these ions is therefore a sensitive testing ground for quantum electrodynamical (QED) effects and especially the electron-nucleus interaction under such extreme conditions. However, insufficient knowledge of the nuclear structure has prevented a rigorous test of strong-field QED. Here we present a measurement of the so-called specific difference between the hyperfine splittings in hydrogen-like and lithium-like bismuth 209 Bi 82+,80+ with a precision that is improved by more than an order of magnitude. Even though this quantity is believed to be largely insensitive to nuclear structure and therefore the most decisive test of QED in the strong magnetic field regime, we find a 7-σ discrepancy compared with the theoretical prediction.

Published
2017
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31. Cytopathic killing of peripheral blood CD4(+) T lymphocytes by human immunodeficiency virus type 1 appears necrotic rather than apoptotic and does not require env.

Author

Lenardo MJ, Angleman SB, Bounkeua V, Dimas J, Duvall MG, Graubard MB, Hornung F, Selkirk MC, Speirs CK, Trageser C, Orenstein JO, and Bolton DL

Subjects
CD4-Positive T-Lymphocytes pathology, Cytopathogenic Effect, Viral, Gene Products, env genetics, Gene Products, nef physiology, HIV-1 genetics, Humans, Jurkat Cells, Mutation, Recombination, Genetic, Vesicular stomatitis Indiana virus genetics, Viral Envelope Proteins genetics, nef Gene Products, Human Immunodeficiency Virus, Apoptosis, CD4-Positive T-Lymphocytes virology, Gene Products, env physiology, HIV-1 physiology, Membrane Glycoproteins, Necrosis
Abstract

An important unresolved issue of AIDS pathogenesis is the mechanism of human immunodeficiency virus (HIV)-induced CD4(+) T-lymphocyte destruction. We show here that HIV type 1 (HIV-1) exerts a profound cytopathic effect upon peripheral blood CD4(+) T lymphocytes that resembles necrosis rather than apoptosis. Necrotic cytopathology was found with both laboratory-adapted strains and primary isolates of HIV-1. We carefully investigated the role of env, which has been previously implicated in HIV cytopathicity. HIV-1 stocks with equivalent infectivity were prepared from constructs with either an intact or mutated env coding region and pseudotyped with the glycoprotein of vesicular stomatitis virus (VSV-G) so that the HIV envelope was not rate-limiting for infection. Infected Jurkat T cells died whether or not env was intact; however, the expression of env accelerated death significantly. The accelerated death was blocked by protease inhibitors, indicating that it was due to reinfection by newly produced virus in env(+) cultures. Accordingly, we found no disparity in kinetics in CD4(lo) Jurkat cells. In highly infected peripheral blood T cells, profound necrosis occurred equivalently with both env(+) and env(-) stocks of HIV-1. We also found that HIV-1 cytopathicity was undiminished by the absence of nef. However, viral stocks made by complementation or packaging of HIV-1 genomes with the natural protein-coding sequences replaced by the green fluorescent protein were highly infectious but not cytopathic. Thus, env can accelerate cell death chiefly as an entry function, but one or more viral functions other than env or nef is essential for necrosis of CD4(+) T cells induced by HIV-1.

Published
2002
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32. Differential TCR signaling regulates apoptosis and immunopathology during antigen responses in vivo.

Author

Combadière B, Reis e Sousa C, Trageser C, Zheng LX, Kim CR, and Lenardo MJ

Subjects
Animals, Antigen Presentation, Antigens pharmacology, Apoptosis drug effects, Cell Communication immunology, Cell Death, Cells, Cultured, Clone Cells cytology, Clone Cells drug effects, Clone Cells physiology, Fas Ligand Protein, Female, Liver pathology, Lymphocyte Activation immunology, Membrane Glycoproteins physiology, Mice, Mice, Inbred Strains, Necrosis, Peptides agonists, Peptides immunology, Peptides pharmacology, Signal Transduction drug effects, Signal Transduction physiology, T-Lymphocytes cytology, T-Lymphocytes drug effects, Tumor Necrosis Factor-alpha physiology, Antigens immunology, Apoptosis immunology, Immunity, Cellular immunology, Receptors, Antigen, T-Cell physiology, T-Lymphocytes physiology
Abstract

Clonal selection theories postulate that lymphocyte fate is regulated by antigen receptor specificity. However, lymphocyte apoptosis is induced through nonantigen-specific receptors such as Fas (CD95/APO-1) or TNFR. We define a selective TCR that controls apoptosis by Fas or TNFR stimulation. Variant ligands can deliver this "competence to die" signal without the full TCR signals necessary for cytokine synthesis. These partial agonists regulate T cell deletion in vivo even when Fas or TNF is provided by T cells of unrelated specificity, but they do not cause the liver necrosis that is associated with T cell elimination by the full agonist. Thus, selective signaling ligands regulate T cell deletion and immune damage in vivo and may be important for peripheral T cell tolerance.

Published
1998
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33. Molecular genetic studies in lymphocyte apoptosis and human autoimmunity.

Author

Martin DA, Combadiere B, Hornung F, Jiang D, McFarland H, Siegel R, Trageser C, Wang J, Zheng L, and Lenardo MJ

Subjects
Autoimmune Diseases etiology, Carrier Proteins metabolism, Fas-Associated Death Domain Protein, Humans, Lymphoproliferative Disorders etiology, Protein Binding, Syndrome, fas Receptor metabolism, Adaptor Proteins, Signal Transducing, Apoptosis genetics, Autoimmune Diseases genetics, Lymphocytes immunology, Lymphoproliferative Disorders genetics, fas Receptor genetics
Abstract

Using a genetic approach, we have studied the molecular basis of human autoimmunity with special emphasis on a disease that is due to defective lymphocyte apoptosis. Recently, we and our collaborators have found that the autoimmune/lymphoproliferative syndrome (ALPS), an inherited disease of children comprising marked lymphoid hyperplasia and autoimmune manifestations, is due to abnormalities in the CD95 gene that cause defective lymphocyte apoptosis. Our recent investigations have shown that the mutations in most families with ALPS cause either global or local changes in the structure of a cytoplasmic portion of the molecule called the 'death domain'. These death domain alterations impair binding of the adapter protein FADD/MORT1 and result in a failure to activate apoptotic caspases after CD95 (Fas/APO-1) cross-linking. Mutations in apoptotic caspases may also contribute to the pathogenesis of ALPS in individuals that have no CD95 gene mutations.

Published
1998
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