Antoine Camper

• Aurbakken, Einar; Kristiansen, Håkon Emil; Kvaal, Simen; Camper, Antoine Yves Marie Charles & Pedersen, Thomas Bondo (2026). Ultrafast laser-driven quantum dynamics in positronium chloride. Journal of Chemical Physics. ISSN 0021-9606. 165. doi: 10.1063/5.0335998. Fulltekst i vitenarkiv Vis sammendrag

  We present a computational study of the laser-driven quantum dynamics of positronium (Ps), PsH, and PsCl at the time-dependent Hartree–Fock level of theory. To eliminate finite-basis effects and to properly capture continuum dynamics, we use a spherical polar pseudospectral representation. The multicomponent theory and its implementation are described in detail. We find that relative to H− and Cl−, respectively, the presence of the positron delays electron ionization in PsH, while slightly enhancing electron ionization in PsCl. In both cases, the positronic response is faster than that of the electrons. We propose that the formation of PsCl may be directly observed through photopositron spectra in the multiphoton regime, where PsCl peaks are expected at roughly twice the energy of Ps peaks, making PsCl clearly distinguishable from Ps. In the tunneling regime, however, photopositron rescattering peaks may only be distinguishable if the amount of Ps is sufficiently low.

• Kłosowski; Piwiński, M.; Linek, A.; Grosbart, M.; Ciuryło, R. & Zawada, M. [Vis alle 64 forfattere av denne artikkelen] (2026). Production of negatively charged atomic ions inside a linear Paul trap for the formation of antiprotonic atoms. Radiation Physics and Chemistry. ISSN 0969-806X. 245. doi: 10.1016/j.radphyschem.2026.113884. Fulltekst i vitenarkiv
• Caravita, R.; Campos, S. Alfaro; Auzins, M.; Berghold, M.; Bergmann, B. & Burian, P. [Vis alle 64 forfattere av denne artikkelen] (2025). The AEgIS Experiment: Progress and Future Outlook. Proceedings of Science (PoS). 480. doi: 10.22323/1.480.0024. Fulltekst i vitenarkiv Vis sammendrag

  The AEgIS experiment at CERN is pioneering measurements of gravity, spectroscopy, and interferometry using pulsed antimatter atomic sources. This work provides an overview of the AEgIS experimental setup and highlights recent advancements in antihydrogen production, positronium laser cooling, and the creation of antiprotonic atoms. Key technological developments, including the overhaul of the control system and its impact on precision experiments, are reviewed. Future perspectives for AEgIS before CERN Long Shutdown 3 and beyond are summarized.

• Camper, Antoine Yves Marie Charles; Campos, S. Alfaro; Auzins, M.; Berghold, M.; Bergmann, B. & Burian, P. [Vis alle 64 forfattere av denne artikkelen] (2025). Positronium laser cooling: results and perspectives. Proceedings of Science (PoS). 480. doi: 10.22323/1.480.0047. Fulltekst i vitenarkiv Vis sammendrag

  The experimental demonstration of positronium laser cooling with stationary broadband laser pulses with negative detuning is briefly described. Considerations on the limits of the current experiment and possible future developments follow. In particular, the benefit of positron remoderation, use of a magnetic field, positronium polarization, pulse shaping, coherent laser cooling and deceleration are shortly discussed.

• Ferguson, R. C.; Campos, S. Alfaro; Auzins, M.; Berghold, M.; Bergmann, B. & Burian, P. [Vis alle 52 forfattere av denne artikkelen] (2025). Positron-Positronium Converters in Reflection and Transmission Geometry for Gravitational Experiments with Antihydrogen using Moiré Deflectometry. Journal of Physics: Conference Series (JPCS). ISSN 1742-6588. 3029(1). doi: 10.1088/1742-6596/3029/1/012005. Fulltekst i vitenarkiv
• Caravita, R.; Campos, S. Alfaro; Auzins, M.; Berghold, M.; Bergmann, B. & Burian, P. [Vis alle 65 forfattere av denne artikkelen] (2025). Laser Cooling Positronium with Broadband Laser Pulses. Journal of Physics: Conference Series (JPCS). ISSN 1742-6588. 3029(1). doi: 10.1088/1742-6596/3029/1/012002. Fulltekst i vitenarkiv Vis sammendrag

  The first successful demonstration of broadband laser cooling of positronium (Ps) atoms, obtained within the AEgIS experiment at CERN, is presented here. By employing a custom-designed pulsed alexandrite laser system at 243 nm featuring long-duration pulses of 70 ns and an energy able to saturate the 13S–23P transition over the broad spectrum range of 360 GHz, the temperature of a room-temperature Ps cloud was reduced from 380 K to 170 K in 70 ns. This advancement opens new avenues for precision spectroscopy, antihydrogen production, and fundamental tests with antimatter.

• Rienäcker, Benjamin; Campos, S. Alfaro; Auzins, M.; Berghold, M.; Bergmann, B. & Burian, P. [Vis alle 64 forfattere av denne artikkelen] (2025). Prospects for forward emitted positronium from nanoporous membranes at AEgIS. Proceedings of Science (PoS). 480. doi: 10.22323/1.480.0082. Fulltekst i vitenarkiv
• Rawat, B. S.; Kumar, N.; Rienäcker, B.; Welsch, C. P.; Campos, S. Alfaro & Auzins, M. [Vis alle 50 forfattere av denne artikkelen] (2025). 3D simulation studies of mixed plasma confinement at AEgIS(Equation presented). Proceedings of Science (PoS). 480. doi: 10.22323/1.480.0076. Fulltekst i vitenarkiv Vis sammendrag

  The AEg¯IS (Antimatter Experiment: Gravity, Interferometry and Spectroscopy) project, based at CERN's Antiproton Decelerator (AD) facility seeks to probe the Weak Equivalence Principle (WEP) for antimatter. It has undergone significant enhancements, capitalizing on the increased quantity of colder antiprotons made available by the Extra Low Energy Antiproton Ring (ELENA) decelerator. These improvements aim to create a horizontal pulsed beam of antihydrogen atoms and enable a direct investigation into the impact of gravity. The AEg¯IS experiment consists of a Penning Malmberg trap comprising cylindrical electrodes within a 5 T and a 1 T axial magnetic field region. The 5 T field captures cold antiprotons, while the 1 T field is used for further trapping which ultimately leads to antihydrogen production. To maximize the antihydrogen formation, it is crucial to have a detailed understanding of the properties of trapped antiprotons, which can be achieved by realistic 3D simulation studies for the dynamics of particle confinement. Previous studies indicated antiprotons exhibit greater stability in a shallower potential well \cite{rawat2024sim}. In this work, we examine the dynamics of antiprotons by varying the outer electrode potentials while maintaining constant potentials at the inner electrodes of the electrostatic trap, utilizing an Electrostatic Particle-In-Cell (ES-PIC) solver in the CST (Computer Simulation Technology) studio. We extended the studies on the temporal evolution of a mixed plasma generated with the introduction of electrons inside the trap along with the antiprotons by observing the effect of their properties: density, and temperature. Additionally, we provide an overview of the results obtained for the energy evolution of antiprotons using a Rotating Wall (RW) electrode at different RW frequencies. Finally, we summarize our plans to develop a full digital twin of the AEg¯IS experiment for the next two years, providing valuable insights into the parameters required for optimized experiments

• Berghold, Michael; Orsucci, Davide; Guatieri, Francesco; Alfaro, Sara; Auzins, Marcis & Bergmann, Benedikt [Vis alle 66 forfattere av denne artikkelen] (2025). Real-time antiproton annihilation vertexing with submicrometer resolution. Science Advances. 11(14). doi: 10.1126/sciadv.ads1176. Fulltekst i vitenarkiv Vis sammendrag

  Primary goal of the AEḡIS experiment is to precisely measure the free fall of antihydrogen within Earth’s gravitational field. To this end, cold (≈50 K) antihydrogen will traverse a two-grid moiré deflectometer before annihilating onto a position-sensitive detector, which shall determine the vertical position of the annihilation vertex relative to the grids with micrometric accuracy. Here, we introduce a vertexing detector based on a modified mobile camera sensor and experimentally demonstrate that it can measure the position of antiproton annihilations within μm, a 35-fold improvement over the previous state of the art for real-time antiproton vertexing. These methods are directly applicable to antihydrogen. Moreover, the sensitivity to light of the sensor enables in situ calibration of the moiré deflectometer, substantially reducing systematic errors. This sensor emerges as a breakthrough technology toward the AEḡIS scientific goals and will constitute the basis for the development of a large-area detector for conducting antihydrogen gravity measurements.

• Glöggler, Lisa Theresa; Gusakova, Natali; Rienäcker, Benjamin; Camper, Antoine Yves Marie Charles; Caravita, Ruggero & Huck, Saiva [Vis alle 53 forfattere av denne artikkelen] (2024). Positronium Laser Cooling via the 13S-23P Transition with a Broadband Laser Pulse. Physical Review Letters. ISSN 0031-9007. 132(8). doi: 10.1103/PhysRevLett.132.083402. Fulltekst i vitenarkiv Vis sammendrag

  We report on laser cooling of a large fraction of positronium (Ps) in free flight by strongly saturating the 13⁢𝑆�−23⁢𝑃� transition with a broadband, long-pulsed 243 nm alexandrite laser. The ground state Ps cloud is produced in a magnetic and electric field-free environment. We observe two different laser-induced effects. The first effect is an increase in the number of atoms in the ground state after the time Ps has spent in the long-lived 23⁢𝑃� states. The second effect is one-dimensional Doppler cooling of Ps, reducing the cloud’s temperature from 380(20) to 170(20) K. We demonstrate a 58(9)% increase in the fraction of Ps atoms with 𝑣�1⁢D<3.7×104  m⁢s−1.

• Lévêque-Simon, Kévin; Camper, Antoine Yves Marie Charles; Taïeb, Richard; Caillat, Jérémie; Lévêque, Camille & Giner, Emmanuel (2024). Production of positronium chloride: A study of the charge exchange reaction between Ps and Cl−. Journal of Chemical Physics. ISSN 0021-9606. 160(10). doi: 10.1063/5.0182498. Fulltekst i vitenarkiv Vis sammendrag

  We present cross sections for the formation of positronium chloride (PsCl) in its ground state from the charge exchange between positronium (Ps) and chloride (Cl−) in the range of 10 meV–100 eV Ps energy. We have used theoretical models based on the first Born approximation in its three-body formulation. We simulated the collisions between Ps and Cl− using ab initio binding energies and positronic wave functions at both the mean-field and correlated levels extrapolated to the complete basis set limit. The accuracy of these ab initio data was benchmarked on the PsF system with the existing highly accurate results, including the very recent quantum Monte Carlo results. We have investigated Ps excited states up to n = 4. The results suggest that the channel Ps(n = 2) is of particular interest for the production of PsCl in the ground state and shows that an accurate treatment of correlation effects (i.e., electron–electron and electron–positron correlations) leads to a significant change in the magnitude of the PsCl production cross section with respect to the mean-field level.

• Volponi, Marco; Huck, Saiva; Caravita, Ruggero; Zielinski, Jakub; Kornakov, Georgy & Karprowicz, G. [Vis alle 52 forfattere av denne artikkelen] (2024). CIRCUS: an autonomous control system for antimatter, atomic and quantum physics experiments. EPJ Quantum Technology. ISSN 2662-4400. 11(1). doi: 10.1140/epjqt/s40507-024-00220-6. Fulltekst i vitenarkiv Vis sammendrag

  A powerful and robust control system is a crucial, often neglected, pillar of any modern, complex physics experiment that requires the management of a multitude of different devices and their precise time synchronisation. The AEḡIS collaboration presents CIRCUS, a novel, autonomous control system optimised for time-critical experiments such as those at CERN’s Antiproton Decelerator and, more broadly, in atomic and quantum physics research. Its setup is based on Sinara/ARTIQ and TALOS, integrating the ALPACA analysis pipeline, the last two developed entirely in AEḡIS. It is suitable for strict synchronicity requirements and repeatable, automated operation of experiments, culminating in autonomous parameter optimisation via feedback from real-time data analysis. CIRCUS has been successfully deployed and tested in AEḡIS; being experiment-agnostic and released open-source, other experiments can leverage its capabilities.

• Volponi, M.; Zielinski, J.; Rauschendorfer, T.; Huck, S.; Caravita, R. & Auzins, M. [Vis alle 55 forfattere av denne artikkelen] (2024). TALOS (Total Automation of LabVIEW Operations for Science): A framework for autonomous control systems for complex experiments. Review of Scientific Instruments. ISSN 0034-6748. 95(8). doi: 10.1063/5.0196806. Fulltekst i vitenarkiv Vis sammendrag

  Modern physics experiments are frequently very complex, relying on multiple simultaneous events to happen in order to obtain the desired result. The experiment control system plays a central role in orchestrating the measurement setup: However, its development is often treated as secondary with respect to the hardware, its importance becoming evident only during the operational phase. Therefore, the AEgIS (Antimatter Experiment: Gravity, Interferometry, Spectroscopy) collaboration has created a framework for easily coding control systems, specifically targeting atomic, quantum, and antimatter experiments. This framework, called Total Automation of LabVIEW Operations for Science (TALOS), unifies all the machines of the experiment in a single entity, thus enabling complex high-level decisions to be taken, and it is constituted by separate modules, called MicroServices, that run concurrently and asynchronously. This enhances the stability and reproducibility of the system while allowing for continuous integration and testing while the control system is running. The system demonstrated high stability and reproducibility, running completely unsupervised during the night and weekends of the data-taking campaigns. The results demonstrate the suitability of TALOS to manage an entire physics experiment in full autonomy: being open-source, experiments other than the AEgIS experiment can benefit from it.

• Gusakova, Natali; Camper, Antoine Yves Marie Charles; Caravita, Ruggero; Penasa, Luca; Glöggler, Lisa Theresa & Wolz, Tim [Vis alle 18 forfattere av denne artikkelen] (2024). An alexandrite laser system for positronium laser cooling. Optics and Laser Technology. ISSN 0030-3992. 182(B). doi: 10.1016/j.optlastec.2024.112097. Fulltekst i vitenarkiv Vis sammendrag

  We report on a Q-switched alexandrite based ∼100ns long pulse duration ultra-violet laser system. The central wavelength of the fundamental pulse is set by a Volume Bragg Grating in reflection and can be tuned between 728nm and 742nm. The spectral bandwidth is ∼130GHz. This laser system was designed in view of Doppler cooling of a cloud of a near room temperature positronium by strongly saturating the 13S–23P transition. In addition, we report on the development of a KD*P Pockels cell driver designed to both Q-switch the cavity and induce a sharp falling edge of the laser pulse so that the end of the positronium-laser interaction time can be controlled with nanosecond precision.

• Malamant, Jan; Gusakova, Natali; Sandaker, Heidi; Sorokina, Irina T; Comparat, Daniel & Camper, Antoine Yves Marie Charles (2024). Coherent laser cooling with trains of ultrashort laser pulses. arXiv.org. ISSN 2331-8422. doi: 10.48550/arXiv.2402.17052. Fulltekst i vitenarkiv
• Malamant, Jan; Gusakova, Natali; Sandaker, Heidi; Sorokina, Irina T; Comparat, D. & Camper, Antoine Yves Marie Charles (2024). Coherent laser cooling with trains of ultrashort laser pulses. Physical Review A (PRA). ISSN 2469-9926. 110(1). doi: 10.1103/PhysRevA.110.013109. Fulltekst i vitenarkiv Vis sammendrag

  We propose to extend coherent laser cooling from narrowband to broadband transitions by using trains of ultrashort broadband pulses. We analytically study two possible methods to reduce the momentum spread of a distribution by several units of photon momentum in a single spontaneous emission lifetime. We report on numerical simulations of one-dimensional laser cooling of a two-level system with realistic parameters. With this scheme, coherent laser cooling can in particular be implemented in the case of fast species with a short lifetime such as positronium.

• Leshchenko, Vyacheslav; Hageman, Stephen J.; Cariker, Coleman; Smith, Gregory; Camper, Antoine Yves Marie Charles & Talbert, Bradford K. [Vis alle 9 forfattere av denne artikkelen] (2023). Kramers–Kronig relation in attosecond transient absorption spectroscopy. Optica. 10(2), s. 142–146. doi: 10.1364/OPTICA.474960. Fulltekst i vitenarkiv Vis sammendrag

  The Kramers–Kronig relation (KKR) has a wide range of applications in extreme ultraviolet (XUV) and x-ray spectroscopy. However, the validity of KKR for many of these applications has not been systematically studied, while it is known to require careful attention in nonlinear and pump–probe experiments in optical domain spectroscopy. Here, we study the validity of KKR in XUV attosecond transient absorption spectroscopy pump–probe measurements both experimentally and theoretically using argon Fano resonances as a case study. Experiments are enabled by a phase-resolved method dubbed Complex Attosecond Transient-absorption Spectroscopy (CATS). Although the estimations based on the rotating-wave approximation suggest that KKR violation could be expected in the studied case, our results validate KKR and provide a solid basis for its application in a broad range of attosecond spectroscopy experiments.

• Huck, Saiva; Auzins, Marcis; Bergmann, Benedikt; Burian, Petr; Brusa, Roberto Sennen & Camper, Antoine Yves Marie Charles [Vis alle 52 forfattere av denne artikkelen] (2023). Toward a pulsed antihydrogen beam for WEP tests in AEgIS. The European Physical Journal Conferences. ISSN 2101-6275. doi: 10.1051/epjconf/202328201005. Fulltekst i vitenarkiv Vis sammendrag

  The AEg̅IS collaboration at CERN’s AD produces antihydrogen atoms in the form of a pulsed, isotropic source with a precisely defined formation time. AEg̅IS has recently undergone major upgrades to fully benefit from the increased number of colder antiprotons provided by the new ELENA decelerator and to move toward forming a horizontal beam to directly investigate the influence of gravity on the H̅ atoms, thereby probing the Weak Equivalence Principle for antimatter. This contribution gives an overview of these upgrades as well as subsequent results from the first beam times with ELENA.

• Camper, Antoine Yves Marie Charles; Ferré, Amélie; Blanchet, Valérie; Descamps, Dominique; Lin, Nan & Petit, Stéphane [Vis alle 10 forfattere av denne artikkelen] (2023). Quantum-Path-Resolved Attosecond High-Harmonic Spectroscopy. Physical Review Letters. ISSN 0031-9007. 130(8). doi: 10.1103/PhysRevLett.130.083201. Fulltekst i vitenarkiv Vis sammendrag

  Strong-field ionization of molecules releases electrons which can be accelerated and driven back to recombine with their parent ion, emitting high-order harmonics. This ionization also initiates attosecond electronic and vibrational dynamics in the ion, evolving during the electron travel in the continuum. Revealing this subcycle dynamics from the emitted radiation usually requires advanced theoretical modeling. We show that this can be avoided by resolving the emission from two families of electronic quantum paths in the generation process. The corresponding electrons have the same kinetic energy, and thus the same structural sensitivity, but differ by the travel time between ionization and recombination—the pump-probe delay in this attosecond self-probing scheme. We measure the harmonic amplitude and phase in aligned CO2 and N2 molecules and observe a strong influence of laser-induced dynamics on two characteristic spectroscopic features: a shape resonance and multichannel interference. This quantum-path-resolved spectroscopy thus opens wide prospects for the investigation of ultrafast ionic dynamics, such as charge migration.

• Glöggler, L.; Caravita, R.; Auzins, M.; Bergmann, B.; Brusa, R.S. & Burian, P. [Vis alle 45 forfattere av denne artikkelen] (2022). High-resolution MCP-TimePix3 imaging/timing detector for antimatter physics. Measurement Science and Technology. ISSN 0957-0233. 33(11). doi: 10.1088/1361-6501/ac8221. Fulltekst i vitenarkiv Vis sammendrag

  We present a hybrid imaging/timing detector for force sensitive inertial measurements designed for measurements on positronium, the metastable bound state of an electron and a positron, but also suitable for applications involving other low intensity, low energy beams of neutral (antimatter)-atoms, such as antihydrogen. The performance of the prototype detector was evaluated with a tunable low energy positron beam, resulting in a spatial resolution of ${\approx}$12 mm, a detection efficiency of up to 40% and a time-resolution in the order of tens of ns.

• Amsler, Claude; Antonello, Massimiliano; Belov, Alexander; Bonomi, Germano; Brusa, Roberto Sennen & Caccia, Massimo [Vis alle 56 forfattere av denne artikkelen] (2021). Pulsed production of antihydrogen. Communications Physics. 4. doi: 10.1038/s42005-020-00494-z. Fulltekst i vitenarkiv Vis sammendrag

  Antihydrogen atoms with K or sub-K temperature are a powerful tool to precisely probe the validity of fundamental physics laws and the design of highly sensitive experiments needs antihydrogen with controllable and well defined conditions. We present here experimental results on the production of antihydrogen in a pulsed mode in which the time when 90% of the atoms are produced is known with an uncertainty of ~250 ns. The pulsed source is generated by the charge-exchange reaction between Rydberg positronium atoms—produced via the injection of a pulsed positron beam into a nanochanneled Si target, and excited by laser pulses—and antiprotons, trapped, cooled and manipulated in electromagnetic traps. The pulsed production enables the control of the antihydrogen temperature, the tunability of the Rydberg states, their de-excitation by pulsed lasers and the manipulation through electric field gradients. The production of pulsed antihydrogen is a major landmark in the AEg¯IS experiment to perform direct measurements of the validity of the Weak Equivalence Principle for antimatter.

• Mariazzi, Sebastiano; Caravita, Ruggero; Zimmermann, Christian; Rienaecker, Benjamin; Camper, Antoine Yves Marie Charles & Belov, Alexander Stepanovich [Vis alle 27 forfattere av denne artikkelen] (2021). High-yield thermalized positronium at room temperature emitted by morphologically tuned nanochanneled silicon targets. Journal of Physics B: Atomic, Molecular and Optical Physics. ISSN 0953-4075. doi: 10.1088/1361-6455/abf6b6. Fulltekst i vitenarkiv Vis sammendrag

  Abstract Nanochanneled silicon targets with high positron/positronium (Ps) conversion rate and efficient Ps cooling were produced. Morphological parameters of the nanochannels, such as their diameter and length, were adjusted to get a large fraction of thermalized Ps at room temperature being emitted into vacuum. Ps cooling measurements were conducted combining single-shot positron annihilation lifetime spectroscopy and Doppler spectroscopy of the 1 3 S → 2 3 P transition. 2 γ –3 γ annihilation ratio measurements were also performed to estimate the positron/Ps conversion efficiency. In a converter with nanochannel diameter of 7–10 nm and depth of 3.89 μ m, ∼28% of implanted positrons with an energy of 3.3 keV was found to be emitted as Ps with a transverse kinetic energy of 11 ± 2 meV. The reduction of the nanochannels depth to 1.13 μ m, without changing the nanochannel diameter, was found to result in a less efficient cooling, highlighting the presence of Ps reflection from the bottom end of nanochannels.

• Zimmer, Christian; Yzombard, Pauline; Camper, Antoine & Comparat, Daniel (2021). Positronium laser cooling in a magnetic field. Physical Review A (PRA). ISSN 2469-9926. doi: 10.1103/PhysRevA.104.023106. Fulltekst i vitenarkiv Vis sammendrag

  We study realistic 3D laser cooling of positronium (Ps) in the presence of a magnetic field. Triplet and singlet states mixing due to the magnetic field, and dynamical Stark effect, generally produce higher annihilation rates than in the zero-field case. 3D cooling is efficient only at very low field B≲50mT and at high field values B⪆0.7T. Near 100ns long laser pulses, spectrally broad enough to cover most of the Ps Doppler profile and with energy in the mJ range, are required to cool Ps. Simulations based on full diagonalization of the Stark and Zeeman Hamiltonian and a kinetic Monte Carlo algorithm exactly solving the rate equations indicate that an efficient cooling (typically from 300K down to below 50K) is possible even in a magnetic field. We also propose 3D moving molasses cooling that can produce a well-defined monochromatic Ps beam useful for applications.

• Antonello, M; Belov, A; Bonomi, G; Brusa, Roberto Sennen; Caccia, M & Camper, Antoine [Vis alle 47 forfattere av denne artikkelen] (2020). Rydberg-positronium velocity and self-ionization studies in a 1T magnetic field and cryogenic environment. Physical Review A (PRA). ISSN 2469-9926. 102(1). doi: 10.1103/PhysRevA.102.013101. Fulltekst i vitenarkiv Vis sammendrag

  We characterized the pulsed Rydberg-positronium production inside the Antimatter Experiment: Gravity, Interferometry, Spectroscopy (AE¯gIS) apparatus in view of antihydrogen formation by means of a charge exchange reaction between cold antiprotons and slow Rydberg-positronium atoms. Velocity measurements on the positronium along two axes in a cryogenic environment (≈10K) and in 1T magnetic field were performed. The velocimetry was done by microchannel-plate (MCP) imaging of a photoionized positronium previously excited to the n=3 state. One direction of velocity was measured via Doppler scan of this n=3 line, another direction perpendicular to the former by delaying the exciting laser pulses in a time-of-flight measurement. Self-ionization in the magnetic field due to the motional Stark effect was also quantified by using the same MCP-imaging technique for Rydberg positronium with an effective principal quantum number neff ranging between 14 and 22. We conclude with a discussion about the optimization of our experimental parameters for creating Rydberg positronium in preparation for an efficient pulsed production of antihydrogen.

• Tietje, Ingemari C.; Amsler, Claude; Antonello, M; Belov, A.; Bonomi, G. & Brusa, Roberto S. [Vis alle 56 forfattere av denne artikkelen] (2020). Protocol for pulsed antihydrogen production in the AEgIS apparatus. Journal of Physics: Conference Series (JPCS). ISSN 1742-6588. 1612(1). doi: 10.1088/1742-6596/1612/1/012025. Fulltekst i vitenarkiv
• Mariazzi, S; Caravita, R; Vespertini, A; Camper, Antoine; Rienäcker, B & Brusa, R.S. [Vis alle 54 forfattere av denne artikkelen] (2020). Techniques for Production and Detection of 23S Positronium. Acta Physica Polonica. A. ISSN 0587-4246. 137(2), s. 91–95. doi: 10.12693/APhysPolA.137.91. Fulltekst i vitenarkiv
• Amsler, Claude; Antonello, Massimiliano; Belov, A.; Bonomi, G.; Brusa, Roberto S. & Caccia, Massimo [Vis alle 58 forfattere av denne artikkelen] (2020). A cryogenic tracking detector for antihydrogen detection in the AEgIS experiment. Nuclear Instruments and Methods in Physics Research Section A : Accelerators, Spectrometers, Detectors and Associated Equipment. ISSN 0168-9002. 960. doi: 10.1016/j.nima.2020.163637. Fulltekst i vitenarkiv

Se alle arbeider i NVA

• Pedersen, Thomas Bondo; Aurbakken, Einar; Kristiansen, Håkon Emil; Kvaal, Simen & Camper, Antoine Yves Marie Charles (2026). Mean-field theory of ultrafast laser-driven quantum dynamics in positronium chloride. Fulltekst i vitenarkiv
• Camper, Antoine Yves Marie Charles (2023). AEgIS: the fall of antimatter. Fulltekst i vitenarkiv
• Camper, Antoine Yves Marie Charles (2023). Pulsed production of antihydrogen. Fulltekst i vitenarkiv
• Camper, Antoine Yves Marie Charles (2023). Positronium manipulation with long laser pulses. Fulltekst i vitenarkiv
• Camper, Antoine Yves Marie Charles & Rienaecker, Benjamin (2021). Antihydrogen pulses for testing gravity at AEgIS. Fulltekst i vitenarkiv
• Camper, Antoine Yves Marie Charles (2021). Antihydrogen pulses in AEgIS. Fulltekst i vitenarkiv

Se alle arbeider i NVA