18 results on '"Böker, J."'
Search Results
2. Measurement of proton-proton elastic scattering into the Coulomb region at Pbeam = 2.5, 2.8 and 3.2 GeV/c
- Author
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Xu, H., Zhou, Y., Bechstedt, U., Böker, J., Gillitzer, A., Goldenbaum, F., Grzonka, D., Hu, Q., Khoukaz, A., Klehr, F., Lorentz, B., Prasuhn, D., Ritman, J., Schadmand, S., Sefzick, T., Stockmanns, T., Strakovsky, I.I., Täschner, A., Wilkin, C., Workman, R.L., and Wüstner, P.
- Published
- 2021
- Full Text
- View/download PDF
3. Storage Ring to Search for Electric Dipole Moments of Charged Particles -- Feasibility Study
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Abusaif, F., Aggarwal, A., Aksentev, A., Alberdi-Esuain, B., Atanasov, A., Barion, L., Basile, S., Berz, M., Beyß, M., Böhme, C., Böker, J., Borburgh, J., Carli, C., Ciepał, I., Ciullo, G., Contalbrigo, M., De Conto, J.-M., Dymov, S., Felden, O., Gagoshidze, M., Gaisser, M., Gebel, R., Giese, N., Grigoryev, K., Grzonka, D., Haj Tahar, M., Hahnraths, T., Heberling, D., Hejny, V., Hetzel, J., Hölscher, D., Javakhishvili, O., Jorat, L., Kacharava, A., Kamerdzhiev, V., Karanth, S., Käseberg, C., Keshelashvili, I., Koop, I., Kulikov, A., Laihem, K., Lamont, M., Lehrach, A., Lenisa, P., Lomidze, N., Lorentz, B., Macharashvili, G., Magiera, A., Makino, K., Martin, S., Mchedlishvili, D., Meißner, U.-G, Metreveli, Z., Michaud, J., Müller, F., Nass, A., Natour, G., Nikolaev, N., Nogga, A., Pesce, A., Poncza, V., Prasuhn, D., Pretz, J., Rathmann, F., Ritman, J., Rosenthal, M., Saleev, A., Schott, M., Sefzick, T., Senichev, Y., Shergelashvili, D., Shmakova, V., Siddique, S., Silenko, A., Simon, M., Slim, J., Soltner, H., Stahl, A., Stassen, R., Stephenson, E., Straatmann, H., Ströher, H., Tabidze, M., Tagliente, G., Talman, R., Uzikov, Yu., Valdau, Yu., Valetov, E., Wagner, T., Weidemann, C., Wirzba, A., Wrońska, A., Wüstner, P., Zupranski, P., Zurek., M., Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), CERN, and CPEDM
- Subjects
lifetime ,experimental methods ,deuteron: electric moment ,[PHYS.PHYS.PHYS-ACC-PH]Physics [physics]/Physics [physics]/Accelerator Physics [physics.acc-ph] ,feedback ,Juelich COSY PS ,[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex] ,sensitivity ,charged particle ,particle: spin ,electric field ,particle: velocity ,error: statistical ,synchrotron ,dipole: electric ,[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex] ,proposed experiment ,spin: polarization - Abstract
CERN Yellow Reports: Monographs Published by CERN; International audience; The proposed method exploits charged particles confined as a storage ring beam (proton, deuteron, possibly $^3$He) to search for an intrinsic electric dipole moment (EDM) aligned along the particle spin axis. Statistical sensitivities can approach $10^{29} e$ cm. The challenge will be to reduce systematic errors to similar levels. The ring will be adjusted to preserve the spin polarization, initially parallel to the particle velocity, for times in excess of 15 minutes. Large radial electric fields, acting through the EDM, will rotate the polarization. The slow rise in the vertical polarization component, detected through scattering from a target, signals the EDM. The project strategy is outlined. It foresees a step-wise plan, starting with ongoing COSY activities that demonstrate technical feasibility. Achievements to date include reduced polarization measurement errors, long horizontal-plane polarization lifetimes, and control of the polarization direction through feedback from the scattering measurements. The project continues with a proof-of-capability measurement (precursor experiment; first direct deuteron EDM measurement), an intermediate prototype ring (proof-of-principle; demonstrator for key technologies), and finally the high precision electric-field storage ring.
- Published
- 2021
4. Storage ring to search for electric dipole moments of charged particles: Feasibility study
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Monographs, CERN Yellow Reports, Abusaif, F., Böhme, C., Zupranski, P., Zurek, M., Böker, J., Borburgh, J., Canale, N., Carli, C., Ciepał, I., Ciullo, G., Contalbrigo, M., De Conto, J.-M., Dymov, S., Aggarwal, A., Felden, Olaf, Gaisser, M., Gebel, Ralf Heinz, Giese, N., Gooding, J., Grigoryev, Kirill, Grzonka, D., Haj Tahar, M., Hahnraths, T., Heberling, D., Aksentev, A., Hejny, V., Hetzel, Jan Henry, Hölscher, D., Javakhishvili, O., Jorat, L., Kacharava, A., Kamerdzhiev, Vsevolod, Karanth, S., Keshelashvili, Irakli, Koop, I., Alberdi-Esuain, B., Kulikov, A., Laihem, Karim, Lamont, M., Lehrach, A., Lenisa, P., Lomidze, I., Lomidze, N., Lorentz, B., Macharashvili, G., Magiera, A., Andres, A., Makino, K., Martin, S., Mchedlishvili, D., Meißner, U.-G., Metreveli, Z., Michaud, J., Müller, F., Nass, A., Natour, G., Nikolaev, N., Atanasov, A., Nogga, A., Okropiridze, Dachi, Pesce, A., Poncza, V., Prasuhn, Dieter, Pretz, J., Rathmann, F., Ritman, James, Rosenthal, M., Saleev, A., Barion, L., Schott, M., Sefzick, T., Senichev, Y., Shankar, R., Shergelashvili, D., Shmakova, V., Siddique, Saad, Silenko, A., Simon, M., Slim, Jamal, Basile, S., Soltner, H., Stahl, A., Stassen, Rolf, Stephenson, E., Straatmann, H., Ströher, Hans, Tabidze, M., Tagliente, G., Talman, R., Uzikov, Y., Berz, M., Valdau, Yury, Valetov, E., Vilella, E., Vitz, M., Vossebeld, J., Wagner, Tim, Weidemann, C., Wirzba, A., Wronska, A., and Wüstner, P.
- Abstract
Geneva : CERN Yellow Reports: Monographs 22MB (2021). doi:10.23731/CYRM-2021-003, Published by CERN Yellow Reports: Monographs, Geneva
- Published
- 2021
- Full Text
- View/download PDF
5. Feasibility Study for an EDM Storage Ring
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Abusaif, F., Aggarwal, A., Aksentev, A., Alberdi-Esuain, B., Barion, L., Basile, S., Berz, M., Beyß, M., Böhme, C., Böker, J., Borburgh, J., Carli, C., Ciepał, I., Ciullo, G., Contalbrigo, M., M Conto, J., Dymov, S., Engels, R., Felden, O., Gagoshidze, M., Gaisser, M., Gebel, R., Giese, N., Grigoryev, K., Grzonka, D., Hanraths, T., Hanhart, C., Heberling, D., Hejny, V., Hetzel, J., Hölscher, D., Otari Javakhishvili, Kacharava, A., Karanth, S., Käseberg, C., Kamerdzhiev, V., Keshelashvili, I., Koop, I., Kulikov, A., Laihem, K., Lamont, M., Lehrach, A., Lenisa, P., Lomidze, N., Lorentz, B., Macharashvili, G., Magiera, A., Maier, R., Makino, K., Martin, S., Mchedlishvili, D., G Meißner, U., Metreveli, Z., Michaud, J., Müller, F., Nass, A., Natour, G., Nikolaev, N., Nogga, A., Pesce, A., Poncza, V., Prasuhn, D., Pretz, J., Rathmann, F., Ritman, J., Rosenthal, M., Saleev, A., Schott, M., Sefzick, T., Senichev, Y., Shergelashvili, D., Shmakova, V., Siddique, S., Silenko, A., Simon, M., Slim, J., Soltner, H., Stahl, A., Stassen, R., Stephenson, E., Straatmann, H., Ströher, H., Tabidze, M., Tagliente, G., Tahar, M., Talman, R., Yu. Uzikov, Yu. Valdau, Valetov, E., Wagner, T., Weidemann, C., Wilkin, C., Wirzba, A., Wrońska, A., Wüstner, P., Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), and CPEDM
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Accelerator Physics (physics.acc-ph) ,experimental methods ,deuteron: electric moment ,hep-ex ,[PHYS.PHYS.PHYS-ACC-PH]Physics [physics]/Physics [physics]/Accelerator Physics [physics.acc-ph] ,FOS: Physical sciences ,costs ,Juelich COSY PS ,sensitivity ,Accelerators and Storage Rings ,High Energy Physics - Experiment ,High Energy Physics - Experiment (hep-ex) ,beam optics ,[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex] ,Physics - Accelerator Physics ,spin: polarization ,Nuclear Experiment ,Particle Physics - Experiment ,accelerator: design ,activity report ,physics.acc-ph - Abstract
This project exploits charged particles confined as a storage ring beam (proton, deuteron, possibly $^3$He) to search for an intrinsic electric dipole moment (EDM, $\vec d$) aligned along the particle spin axis. Statistical sensitivities can approach $10^{-29}$~e$\cdot$cm. The challenge will be to reduce systematic errors to similar levels. The ring will be adjusted to preserve the spin polarization, initially parallel to the particle velocity, for times in excess of 15 minutes. Large radial electric fields, acting through the EDM, will rotate the polarization ($\vec d \times\vec E$). The slow rise in the vertical polarization component, detected through scattering from a target, signals the EDM. The project strategy is outlined. It foresees a step-wise plan, starting with ongoing COSY activities that demonstrate technical feasibility. Achievements to date include reduced polarization measurement errors, long horizontal-plane polarization lifetimes, and control of the polarization direction through feedback from the scattering measurements. The project continues with a proof-of-capability measurement (precursor experiment; first direct deuteron EDM measurement), an intermediate prototype ring (proof-of-principle; demonstrator for key technologies), and finally the high precision electric-field storage ring.
- Published
- 2019
6. A new beam polarimeter at COSY to search for electric dipole moments of charged particles.
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Müller, F., Javakhishvili, O., Shergelashvili, D., Keshelashvili, I., Mchedlishvili, D., Abusaif, F., Aggarwal, A., Barion, L., Basile, S., Böker, J., Canale, N., Ciullo, G., Dymov, S., Felden, O., Gagoshidze, M., Gebel, R., Demary, N., Grigoryev, K., Grzonka, D., and Hahnraths, T.
- Published
- 2020
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7. How to reach a thousand-second in-plane polarization lifetime with 0.97−GeV/c deuterons in a storage ring
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Guidoboni, G., Stephenson, E., Böker, J., Wüstner, P., Zakrzewska, M., Zuprański, P., Zyuzin, D., Stroeher, Hans, Mey, Sebastian, Stahl, Achim, JEDI Collaboration, Böhme, C., Bsaisou, J., Chekmenev, S., Chiladze, D., Ciullo, G., Contalbrigo, M., de Conto, J.-M., Dymov, S., Engels, Ralf W., Andrianov, S., Esser, F. M., Eversmann, D., Felden, O., Gaisser, M., Gebel, R., Glückler, H., Goldenbaum, F., Grigoryev, K., Grzonka, D., Hahnraths, T., Augustyniak, W., Heberling, D., Hejny, V., Hempelmann, N., Hetzel, J., Hinder, F., Hipple, R., Hölscher, D., Ivanov, A., Kacharava, A., Kamerdzhiev, V., Bagdasarian, Z., Kamys, B., Keshelashvili, I., Khoukaz, A., Koop, I., Krause, H.-J., Krewald, S., Kulikov, A., Lehrach, A., Lenisa, P., Lomidze, N., Bai, M., Lorentz, B., Maanen, P., Macharashvili, G., Magiera, A., Maier, R., Makino, K., Mariański, B., Mchedlishvili, D., Meißner, Ulf-G., Mey, S., Baylac, M., Morse, W., Müller, F., Nass, A., Natour, G., Nikolaev, N., Nioradze, M., Nowakowski, K., Orlov, Y., Pesce, A., Prasuhn, D., Bernreuther, W., Pretz, J., Rathmann, F., Ritman, J., Rosenthal, M., Rudy, Z., Saleev, A., Sefzick, T., Semertzidis, Y., Senichev, Y., Shmakova, V., Bertelli, S., Silenko, A., Simon, M., Slim, J., Soltner, H., Stassen, R., Statera, M., Stockhorst, H., Straatmann, H., Tabidze, M., Talman, R., Berz, M., Thörngren Engblom, P., Trinkel, F., Trzciński, A., Uzikov, Yu., Valdau, Yu., Valetov, E., Vassiliev, A., Weidemann, C., Wilkin, C., Wrońska, A., Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Centre National de la Recherche Scientifique (CNRS), and JEDI
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ANOMALOUS MAGNETIC-MOMENTS ,ELECTRIC-DIPOLE MOMENTS ,SENSITIVITY ,[PHYS.PHYS.PHYS-ACC-PH]Physics [physics]/Physics [physics]/Accelerator Physics [physics.acc-ph] ,ddc:550 ,Socio-culturale ,Physics::Accelerator Physics ,Nuclear Experiment - Abstract
International audience; We observe a deuteron beam polarization lifetime near 1000 s in the horizontal plane of a magnetic storage ring (COSY). This long spin coherence time is maintained through a combination of beam bunching, electron cooling, sextupole field corrections, and the suppression of collective effects through beam current limits. This record lifetime is required for a storage ring search for an intrinsic electric dipole moment on the deuteron at a statistical sensitivity level approaching 10−29 e cm.
- Published
- 2016
8. Associations of insulin‐like growth factor‐I and insulin‐like growth factor binding protein‐3 with bone quality in the general adult population.
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Böker, J., Völzke, H., Nauck, M., Hannemann, A., and Friedrich, N.
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SOMATOTROPIN , *INSULIN-like growth factor-binding proteins , *BONE metabolism , *BONE density , *ULTRASONIC imaging - Abstract
Summary: Objective: Growth hormone (GH) and its main mediator, insulin‐like growth factor‐I (IGF‐I), play a significant role in bone metabolism. The relations between IGF‐I and bone mineral density (BMD) or osteoporosis have been assessed in previous studies but whether the associations are sex‐specific remains uncertain. Moreover, only a few studies examined bone quality assessed by quantitative ultrasound (QUS). We aimed to investigate these associations in the general population of north‐east Germany. Design and Measurements: Data from 1759 men and 1784 women who participated in the baseline examination of the Study of Health in Pomerania (SHIP)‐Trend were used. IGF‐I and IGF‐binding protein‐3 (IGFBP‐3) concentrations were measured on the IDS‐iSYS multidiscipline automated analyser (Immunodiagnostic Systems Limited). QUS measurements were performed at the heel (Achilles InSight, GE Healthcare). Sex‐specific linear and multinomial logistic regression models adjusted for potential confounders were calculated. Results: Linear regression analyses revealed significant positive associations between IGF‐I and IGF‐I/IGFBP‐3 ratio, a marker for free IGF‐I, with all QUS parameters in men. Among women, we found an inverse association between IGF‐I and the QUS‐based fracture risk but no association with any other QUS parameter. There was no association between IGFBP‐3 and the QUS‐based fracture risk. Conclusions: Our data suggest an important role of IGF‐I on bone quality in men. The observed association of IGF‐I with the QUS‐based stiffness index and QUS‐based fracture risk in this study might animate clinicians to refer patients with low IGF‐I levels, particularly men, to a further evaluation of risk factors for osteoporosis and a detailed examination of the skeletal system. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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9. Dynamics and structure of self-generated magnetics fields on solids following high contrast, high intensity laser irradiation.
- Author
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Albertazzi, B., Chen, S. N., Antici, P., Böker, J., Borghesi, M., Breil, J., Dervieux, V., Feugeas, J. L., Lancia, L., Nakatsutsumi, M., Nicolaï, Ph., Romagnagni, L., Shepherd, R., Sentoku, Y., Starodubtsev, M., Swantusch, M., Tikhonchuk, V. T., Willi, O., d'Humières, E., and Pépin, H.
- Subjects
MAGNETIC fields ,LASER beams ,NUMERICAL analysis ,HOT carriers ,TEMPERATURE effect - Abstract
The dynamics of self-generated magnetic B-fields produced following the interaction of a high contrast, high intensity (I>10
19 W cm-2 ) laser beam with thin (3 μm thick) solid (Al or Au) targets is investigated experimentally and numerically. Two main sources drive the growth of B-fields on the target surfaces. B-fields are first driven by laser-generated hot electron currents that relax over ~10-20 ps. Over longer timescales, the hydrodynamic expansion of the bulk of the target into vacuum also generates B-field induced by non-collinear gradients of density and temperature. The laser irradiation of the target front side strongly localizes the energy deposition at the target front, in contrast to the target rear side, which is heated by fast electrons over a much larger area. This induces an asymmetry in the hydrodynamic expansion between the front and rear target surfaces, and consequently the associated B-fields are found strongly asymmetric. The sole long-lasting (>30 ps) B-fields are the ones growing on the target front surface, where they remain of extremely high strength (~8-10 MG). These B-fields have been recently put by us in practical use for focusing laser-accelerated protons [B. Albertazzi et al., Rev. Sci. Instrum. 86, 043502 (2015)]; here we analyze in detail their dynamics and structure. [ABSTRACT FROM AUTHOR]- Published
- 2015
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10. Quantum Vortex Core and Missing Pseudogap in the Multiband BCS-BEC Crossover Superconductor FeSe.
- Author
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Hanaguri, T., Kasahara, S., Böker, J., Eremin, I., Shibauchi, T., and Matsuda, Y.
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BCS theory (Superconductivity) , *SUPERCONDUCTING transition temperature , *BOSE-Einstein condensation - Abstract
FeSe is argued as a superconductor in the Bardeen-Cooper-Schrieffer Bose-Einstein condensation crossover regime where the superconducting gap size and the superconducting transition temperature Tc are comparable to the Fermi energy. In this regime, vortex bound states should be well quantized and the preformed pairs above Tc may yield a pseudogap in the quasiparticle-excitation spectrum. We performed spectroscopic-imaging scanning tunneling microscopy to search for these features. We found Friedel-like oscillations near the vortex, which manifest the quantized levels, whereas the pseudogap was not detected. These apparently conflicting observations may be related to the multiband nature of FeSe. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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11. Evidence for an Fulde-Ferrell-Larkin-Ovchinnikov State with Segmented Vortices in the BCS-BEC-Crossover Superconductor FeSe.
- Author
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Kasahara, S., Sato, Y., Licciardello, S., Čulo, M., Arsenijević, S., Ottenbros, T., Tominaga, T., Böker, J., Eremin, I., Shibauchi, T., Wosnitza, J., Hussey, N. E., and Matsuda, Y.
- Subjects
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FLUX-line lattice , *FIRST-order phase transitions , *SUPERCONDUCTING transitions , *SPIN-orbit interactions , *SUPERCONDUCTORS , *FERMI energy - Abstract
We present resistivity and thermal-conductivity measurements of superconducting FeSe in intense magnetic fields up to 35 T applied parallel to the ab plane. At low temperatures, the upper critical field μ0Hc2ab shows an anomalous upturn, while thermal conductivity exhibits a discontinuous jump at μ0H∗≈24 T well below μ0Hc2ab, indicating a first-order phase transition in the superconducting state. This demonstrates the emergence of a distinct field-induced superconducting phase. Moreover, the broad resistive transition at high temperatures abruptly becomes sharp upon entering the high-field phase, indicating a dramatic change of the magnetic-flux properties. We attribute the high-field phase to the Fulde-Ferrel-Larkin-Ovchinnikov (FFLO) state, where the formation of planar nodes gives rise to a segmentation of the flux-line lattice. We point out that strongly orbital-dependent pairing as well as spin-orbit interactions, the multiband nature, and the extremely small Fermi energy are important for the formation of the FFLO state in FeSe. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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12. Acceleration of collimated 45 MeV protons by collisionless shocks driven in low-density, large-scale gradient plasmas by a 10 20 W/cm 2 , 1 µm laser.
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Antici P, Boella E, Chen SN, Andrews DS, Barberio M, Böker J, Cardelli F, Feugeas JL, Glesser M, Nicolaï P, Romagnani L, Scisciò M, Starodubtsev M, Willi O, Kieffer JC, Tikhonchuk V, Pépin H, Silva LO, Humières E, and Fuchs J
- Abstract
A new type of proton acceleration stemming from large-scale gradients, low-density targets, irradiated by an intense near-infrared laser is observed. The produced protons are characterized by high-energies (with a broad spectrum), are emitted in a very directional manner, and the process is associated to relaxed laser (no need for high-contrast) and target (no need for ultra-thin or expensive targets) constraints. As such, this process appears quite effective compared to the standard and commonly used Target Normal Sheath Acceleration technique (TNSA), or more exploratory mechanisms like Radiation Pressure Acceleration (RPA). The data are underpinned by 3D numerical simulations which suggest that in these conditions a Low Density Collisionless Shock Acceleration (LDCSA) mechanism is at play, which combines an initial Collisionless Shock Acceleration (CSA) to a boost procured by a TNSA-like sheath field in the downward density ramp of the target, leading to an overall broad spectrum. Experiments performed at a laser intensity of 10
20 W/cm2 show that LDCSA can accelerate, from ~1% critical density, mm-scale targets, up to 5 × 109 protons/MeV/sr/J with energies up to 45(±5) MeV in a collimated (~6° half-angle) manner.- Published
- 2017
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13. How to Reach a Thousand-Second in-Plane Polarization Lifetime with 0.97-GeV/c Deuterons in a Storage Ring.
- Author
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Guidoboni G, Stephenson E, Andrianov S, Augustyniak W, Bagdasarian Z, Bai M, Baylac M, Bernreuther W, Bertelli S, Berz M, Böker J, Böhme C, Bsaisou J, Chekmenev S, Chiladze D, Ciullo G, Contalbrigo M, de Conto JM, Dymov S, Engels R, Esser FM, Eversmann D, Felden O, Gaisser M, Gebel R, Glückler H, Goldenbaum F, Grigoryev K, Grzonka D, Hahnraths T, Heberling D, Hejny V, Hempelmann N, Hetzel J, Hinder F, Hipple R, Hölscher D, Ivanov A, Kacharava A, Kamerdzhiev V, Kamys B, Keshelashvili I, Khoukaz A, Koop I, Krause HJ, Krewald S, Kulikov A, Lehrach A, Lenisa P, Lomidze N, Lorentz B, Maanen P, Macharashvili G, Magiera A, Maier R, Makino K, Mariański B, Mchedlishvili D, Meißner UG, Mey S, Morse W, Müller F, Nass A, Natour G, Nikolaev N, Nioradze M, Nowakowski K, Orlov Y, Pesce A, Prasuhn D, Pretz J, Rathmann F, Ritman J, Rosenthal M, Rudy Z, Saleev A, Sefzick T, Semertzidis Y, Senichev Y, Shmakova V, Silenko A, Simon M, Slim J, Soltner H, Stahl A, Stassen R, Statera M, Stockhorst H, Straatmann H, Ströher H, Tabidze M, Talman R, Thörngren Engblom P, Trinkel F, Trzciński A, Uzikov Y, Valdau Y, Valetov E, Vassiliev A, Weidemann C, Wilkin C, Wrońska A, Wüstner P, Zakrzewska M, Zuprański P, and Zyuzin D
- Abstract
We observe a deuteron beam polarization lifetime near 1000 s in the horizontal plane of a magnetic storage ring (COSY). This long spin coherence time is maintained through a combination of beam bunching, electron cooling, sextupole field corrections, and the suppression of collective effects through beam current limits. This record lifetime is required for a storage ring search for an intrinsic electric dipole moment on the deuteron at a statistical sensitivity level approaching 10^{-29} e cm.
- Published
- 2016
- Full Text
- View/download PDF
14. Amphiphilic amide nitrones: a new class of protective agents acting as modifiers of mitochondrial metabolism.
- Author
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Durand G, Poeggeler B, Ortial S, Polidori A, Villamena FA, Böker J, Hardeland R, Pappolla MA, and Pucci B
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- Animals, Benzothiazoles chemistry, Brain drug effects, Free Radical Scavengers chemical synthesis, Free Radical Scavengers chemistry, Free Radical Scavengers pharmacology, Hydrogen Peroxide chemistry, Magnetic Resonance Spectroscopy, Membrane Potential, Mitochondrial drug effects, Mitochondria drug effects, Nitrogen Oxides chemical synthesis, Optical Rotation, Oxidation-Reduction, Rats, Rats, Sprague-Dawley, Spectrometry, Mass, Electrospray Ionization, Sulfonic Acids chemistry, Surface-Active Agents chemical synthesis, Surface-Active Agents chemistry, Brain metabolism, Mitochondria metabolism, Nitrogen Oxides chemistry, Nitrogen Oxides pharmacology, Oxidative Stress drug effects, Surface-Active Agents pharmacology
- Abstract
Our group has demonstrated that the amphiphilic character of alpha-phenyl-N-tert-butyl nitrone based agents is a key feature in determining their bioactivity and protection against oxidative toxicity. In this work, we report the synthesis of a new class of amphiphilic amide nitrones. Their hydroxyl radical scavenging activity and radical reducing potency were shown using ABTS competition and ABTS(+) reduction assays, respectively. Cyclic voltammetry was used to investigate their redox behavior, and the effects of the substitution of the PBN on the charge density of the nitronyl atoms, the electron affinity, and the ionization potential were computationally rationalized. The protective effects of amphiphilic amide nitrones in cell cultures exposed to oxidotoxins greatly exceeded those exerted by the parent compound PBN. They decreased electron and proton leakage as well as hydrogen peroxide formation in isolated rat brain mitochondria at nanomolar concentration. They also significantly enhanced mitochondrial membrane potential. Finally, dopamine-induced inhibition of complex I activity was antagonized by pretreatment with these agents. These findings indicate that amphiphilic amide nitrones are much more than just radical scavenging antioxidants but may act as a new class of bioenergetic agents directly on mitochondrial electron and proton transport.
- Published
- 2010
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15. Fine-tuning the amphiphilicity: a crucial parameter in the design of potent alpha-phenyl-N-tert-butylnitrone analogues.
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Durand G, Poeggeler B, Böker J, Raynal S, Polidori A, Pappolla MA, Hardeland R, and Pucci B
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- Animals, Antioxidants chemistry, Antioxidants pharmacology, Cells, Cultured, Disaccharides chemical synthesis, Disaccharides chemistry, Disaccharides pharmacology, Drug Design, Electron Transport Complex I metabolism, In Vitro Techniques, Nitrogen Oxides chemistry, Nitrogen Oxides pharmacology, Rats, Rotifera drug effects, Structure-Activity Relationship, Submitochondrial Particles drug effects, Submitochondrial Particles metabolism, Tromethamine analogs & derivatives, Tromethamine chemical synthesis, Tromethamine chemistry, Tromethamine pharmacology, Antioxidants chemical synthesis, Cyclic N-Oxides chemistry, Nitrogen Oxides chemical synthesis
- Abstract
A new series of hydrophilic, lipophilic, and amphiphilic alpha-phenyl-N-tert-butylnitrone (PBN) derivatives were synthesized to explore the relationship between their hydrophilic-lipophilic properties and antioxidant potency. Very potent protective effects of amphiphilic lactobionamide and tris(hydroxymethyl)aminomethane PBN derivatives were observed in mitochondrial preparations, in cell cultures, and in rotifers exposed to unspecific and mitochondria targeted oxidotoxins.
- Published
- 2007
- Full Text
- View/download PDF
16. Toxicity of the quinalphos metabolite 2-hydroxyquinoxaline: growth inhibition, induction of oxidative stress, and genotoxicity in test organisms.
- Author
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Riediger S, Behrends A, Croll B, Vega-Naredo I, Hänig N, Poeggeler B, Böker J, Grube S, Gipp J, Coto-Montes A, Haldar C, and Hardeland R
- Subjects
- Animals, Dinoflagellida genetics, Dinoflagellida growth & development, Insecticides metabolism, Insecticides toxicity, Light, Luminescent Measurements, Mutagenicity Tests, Organothiophosphorus Compounds metabolism, Oxidation-Reduction, Paramecium genetics, Paramecium growth & development, Quinoxalines metabolism, Salmonella typhimurium genetics, Salmonella typhimurium growth & development, Time Factors, Cell Proliferation drug effects, Dinoflagellida drug effects, Organothiophosphorus Compounds toxicity, Oxidative Stress drug effects, Paramecium drug effects, Quinoxalines toxicity, Salmonella typhimurium drug effects
- Abstract
The quinalphos metabolite 2-hydroxyquinoxaline (HQO), previously shown to photocatalytically destroy antioxidant vitamins and biogenic amines in vitro, was tested for toxicity in several small aquatic organisms and for mutagenicity in Salmonella typhimurium. In the rotifer Philodina acuticornis, HQO caused the disappearance of large individuals and increased hydroperoxide concentration. The latter effect was not only observed in animals kept in a light/dark cycle, but also in constant darkness, indicating that HQO can assume a reactive state and/or form reactive intermediates under the influence of either light or redox-active metabolites, in particular, free radicals. Cell proliferation was inhibited in the ciliate Paramecium bursaria. In the dinoflagellate Lingulodinium polyedrum, which allows early detection of cellular stress on the basis of bioluminescence measurements, strong rises in light emission became apparent on the 2nd day of exposure to HQO and continued until cells died between 12 and 18 days of treatment. Oxidative damage of protein by HQO was demonstrated by measuring protein carbonyl in L. polyedrumin vivo as well as in light-exposed bovine serum albumin in vitro. In an Ames test of mutagenicity, HQO proved to be genotoxic in both light- and dark-exposed bacteria. HQO appears as a source of secondary quinalphos toxicity, which deserves further attention.
- Published
- 2007
- Full Text
- View/download PDF
17. Fluorinated amphiphilic amino acid derivatives as antioxidant carriers: a new class of protective agents.
- Author
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Ortial S, Durand G, Poeggeler B, Polidori A, Pappolla MA, Böker J, Hardeland R, and Pucci B
- Subjects
- Amino Acids chemical synthesis, Animals, Cell Death drug effects, Cells, Cultured, Chemical Phenomena, Chemistry, Physical, Doxorubicin toxicity, Hydrogen Peroxide pharmacology, Hydrogen Peroxide toxicity, Molecular Structure, Oxidation-Reduction, Protective Agents chemistry, Protective Agents classification, Surface-Active Agents chemical synthesis, Surface-Active Agents classification, Surface-Active Agents pharmacology, Amino Acids chemistry, Amino Acids pharmacology, Antioxidants chemistry, Fluorine chemistry, Protective Agents chemical synthesis, Protective Agents pharmacology, Surface-Active Agents chemistry
- Abstract
The use of classical antioxidants is limited by their low bioavailabilities, and therefore, high doses are usually required to display significant protective activity. In a recent article (J. Med. Chem. 2003, 46, 5230) we showed that the ability of the alpha-phenyl-N-tert-butylnitrone (PBN) to restore the viability of ATPase-deficient human skin fibroblasts was greatly enhanced by grafting it on a fluorinated amphiphilic carrier. With the aim of extending this concept to other antioxidants, we present here the design, the synthesis, and the physicochemical measurements of a new series of fluorinated amphiphilic antioxidant derivatives. The hydroxyl radical scavenging activity and the radical reducing potency of these newly designed compounds were respectively demonstrated in an ABTS competition and an ABTS(*+) reduction assay. We also showed that the protective effects of amphiphilic antioxidants derived from PBN, Trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid) or lipoic acid (5-[1,2]-dithiolan-3-ylpentanoic acid) in primary cortical mixed cell cultures exposed to oxidotoxins are greatly improved compared to their parent compounds in the following rank-order: (1) PBN, (2) Trolox, and (3) lipoic acid. In contrast, the protective activity of indole-3-propionic acid was slightly decreased by grafting it on the amphiphilic carrier. Similar observations were made in in vivo experiments using aquatic invertebrate microorganisms, called rotifers, which were exposed to lethal concentrations of nonselective (H(2)O(2)) and mitochondria-selective (doxorubicin) oxidotoxins. The conclusion of these studies is that fluorinated amphiphilic PBN, Trolox, and lipoic acid derivatives exhibit very potent protective activities in in vitro and in vivo experiments. The findings demonstrated herein therefore strongly suggest that the amphiphilic character enhances the bioavailability of the antioxidants and allows for a selective targeting of mitochondria.
- Published
- 2006
- Full Text
- View/download PDF
18. Mitochondrial medicine: neuroprotection and life extension by the new amphiphilic nitrone LPBNAH acting as a highly potent antioxidant agent.
- Author
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Poeggeler B, Durand G, Polidori A, Pappolla MA, Vega-Naredo I, Coto-Montes A, Böker J, Hardeland R, and Pucci B
- Subjects
- Aging drug effects, Aging physiology, Amyloid beta-Peptides toxicity, Animals, Cell Line, Tumor, Cell Survival drug effects, Diagnostic Imaging methods, Disaccharides chemical synthesis, Disaccharides chemistry, Disease Models, Animal, Dose-Response Relationship, Drug, Drug Interactions, Humans, Hydrogen Peroxide toxicity, Imines chemical synthesis, Imines chemistry, Mitochondrial Diseases chemically induced, Mitochondrial Diseases mortality, Neuroblastoma, Neuroprotective Agents chemical synthesis, Neuroprotective Agents chemistry, Nitrogen Oxides chemical synthesis, Nitrogen Oxides chemistry, Oxidative Stress drug effects, Rotifera drug effects, Disaccharides therapeutic use, Imines therapeutic use, Life Expectancy, Mitochondrial Diseases prevention & control, Neuroprotective Agents therapeutic use, Nitrogen Oxides therapeutic use
- Abstract
The search for effective treatments that prevent oxidative stress associated with premature ageing and neurodegenerative diseases is an important area of neurochemical research. As age- and disease-related oxidative stress is frequently associated with mitochondrial dysfunction, amphiphilic antioxidant agents of high stability and selectivity that target these organelles can provide on-site protection. Such an amphiphilic nitrone protected human neuroblastoma cells at low micromolar concentrations against oxidative damage and death induced by exposure to the beta-amyloid peptide, hydrogen peroxide and 3-hydroxykynurenine. Daily administration of the antioxidant at a concentration of only 5 mum significantly increased the lifespan of the individually cultured rotifer Philodina acuticornis odiosa Milne. This compound is unique in its exceptional anti-ageing efficacy, being one order of magnitude more potent than any other compound previously tested on rotifers. The nitrone protected these aquatic animals against the lethal toxicity of hydrogen peroxide and doxorubicin and greatly enhanced their survival when co-administered with these oxidotoxins. These findings indicate that amphiphilic antioxidants have a great potential as neuroprotective agents in preventing the death of cells and organisms exposed to enhanced oxidative stress and damage.
- Published
- 2005
- Full Text
- View/download PDF
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