Explanipedia

Atomic Observables Induced by Cosmic Fields Open

Sebastian Lahs, D. Comparat, Fiona Kirk, B. M. Roberts · 2025

The existence of cosmic fields made from yet unknown light bosons is predicted in many extensions to the Standard Model. They are especially of interest as possible constituents of dark matter. To detect such light and weakly interacting f…

Demonstration of deuterium's enhanced sensitivity to symmetry violations governed by the Standard-Model Extension Open

A. Nanda, D. Comparat, Olivier Dulieu, Sebastian Lahs, C. Malbrunot , et al. · 2025

We have performed hyperfine spectroscopy of two transitions in ground-state deuterium and searched for violations of \CPT and Lorentz symmetry that would manifest as sidereal variations of the observed transition frequencies. Several non-r…

Polarizabilities as probes for P, T, and PT violation Open

Sebastian Lahs, D. Comparat · 2024

Searches for violations of the fundamental symmetries of parity P and time reversal T in atomic and molecular systems provide a powerful tool for precise measurements of the physics of and beyond the standard model. In this work, we invest…

An alexandrite laser system for positronium laser cooling Open

Natali Gusakova, A. Camper, R. Caravita, L. Penasa, L. T. Glöggler , et al. · 2024

High repetition rate sub-ns electron pulses from pulsed-resonance Rydberg field-ionization (PRRFI) Open

Raphaël Hahn, D. Comparat · 2024

Coherent laser cooling with trains of ultrashort laser pulses Open

J. Malamant, Natali Gusakova, H. Sandaker, Irina T. Sorokina, D. Comparat , et al. · 2024

We propose to extend coherent laser cooling from narrow-band to broad-band transitions by using trains of ultrashort broadband pulses. We study analytically two possible methods to reduce the momentum spread of a distribution by several un…

Positronium Laser Cooling via the Transition with a Broadband Laser Pulse Open

L. T. Glöggler, Natali Gusakova, B. Rienäcker, A. Camper, R. Caravita , et al. · 2024

We report on laser cooling of a large fraction of positronium (Ps) in free flight by strongly saturating the 13S−23P transition with a broadband, long-pulsed 243 nm alexandrite laser. The ground state Ps cloud is produced in a magnetic and…

An Alexandrite Laser System for Positronium Laser Cooling Open

Natali Gusakova, A. Camper, R. Caravita, L. Penasa, L. T. Glöggler , et al. · 2024

Experimental perspectives on the matter–antimatter asymmetry puzzle: developments in electron EDM and H¯ experiments Open

D. Comparat, C. Malbrunot, S. Malbrunot-Ettenauer, E. Widmann, P. Yzombard · 2023

In the search for clues to the matter–antimatter puzzle, experiments with atoms or molecules play a particular role. These systems allow measurements with very high precision, as demonstrated by the unprecedented limits down to e cm …

Experimental perspectives on the matter-antimatter asymmetry puzzle: developments in electron EDM and antihydrogen experiments Open

D. Comparat, C. Malbrunot, S. Malbrunot-Ettenauer, E. Widmann, P. Yzombard · 2023

In the search for clues to the matter-antimatter puzzle, experiments with atoms or molecules play a particular role. These systems allow measurements with very high precision, as demonstrated by the unprecedented limits down to $10^{-30}$ …

Positronium laser cooling via the $1^3S$-$2^3P$ transition with a broadband laser pulse Open

L. T. Glöggler, Natali Gusakova, B. Rienäcker, A. Camper, R. Caravita , et al. · 2023

We report on laser cooling of a large fraction of positronium (Ps) in free-flight by strongly saturating the $1^3S$-$2^3P$ transition with a broadband, long-pulsed 243 nm alexandrite laser. The ground state Ps cloud is produced in a magnet…

High repetition rate sub ns-electron pulses from Resonant Pulsed Rydberg Field Ionization Open

Raphaël Hahn, D. Comparat · 2023

Using Resonant Pulsed Rydberg Field-ionization (RPRFI) technique, we generate low-energy electron bunches at high repetition rates. By combining continuous-wave laser excitation with a pulsed electric field, this method selectively ionizes…

Cesium atoms in cryogenic argon matrix Open

Thomas Battard, Sebastian Lahs, Claudine Crépin, D. Comparat · 2023

This paper presents both experimental and theoretical investigations into the spectroscopy of dilute cesium (Cs) atoms within a solid argon (Ar) matrix at cryogenic temperatures. This system is relevant for matrix isolation spectroscopy an…

Control system for ion Penning traps at the AEgIS experiment at CERN Open

Dorota Nowicka, B. Bergmann, G. Bonomi, R.S. Brusa, Petr Burian , et al. · 2022

The AEgIS experiment located at the Antiproton Decelerator at CERN aims to measure the gravitational fall of a cold antihydrogen pulsed beam. The precise observation of the antiatoms in the Earth gravitational field requires a controlled p…

Development of a detector for inertial sensing of positronium at AEḡIS (CERN) Open

L. T. Glöggler, R. Caravita, B. Bergmann, G. Bonomi, R.S. Brusa , et al. · 2022

The primary goal of the AEgIS collaboration at CERN is to measure the gravitational acceleration on neutral antimatter. Positronium (Ps), the bound state of an electron and a positron, is a suitable candidate for a force-sensitive inertial…

High-resolution MCP-TimePix3 imaging/timing detector for antimatter physics Open

L. T. Glöggler, R. Caravita, M. Auzins, B. Bergmann, R.S. Brusa , et al. · 2022

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 lo…

Pulsed Production of Antihydrogen in AEgIS Open

N. Zurlo, C. Amsler, M. Antonello, Alexander S. Belov, G. Bonomi , et al. · 2022

Cold antihydrogen atoms are a powerful tool to probe the validity of fundamental physics laws, and it's clear that colder atoms, generally speaking, allow an increased level of precision. After the first production of cold antihydrogen (H …

Comparative analysis of recirculating and collimating cesium ovens Open

Raphaël Hahn, Thomas Battard, Oscar Boucher, Y. J. Picard, Hans Lignier , et al. · 2022

We have performed a study of several cesium oven designs. A comparison between recirculating (or sticking-wall) and collimating (or re-emitting-wall) ovens is made in order to extract the most efficient design in terms of beam brightness. …

Experiments with mid-heavy antiprotonic atoms in AEgIS Open

G. Kornakov, M. Auzins, B. Bergmann, Petr Burian, G. Bonomi , et al. · 2022

Antiprotonic atoms have been fundamental in experiments which provide the most precise data on the strong interaction between protons and antiprotons and of the neutron skin of many nuclei thanks to the clean annihilation signal. In most o…

Simulation of antihydrogen deexcitation in neutral atom traps for improved trapping and cooling Open

C. Malbrunot, T. Wolz, L. Nowak, D. Comparat · 2022

We present results of simulations highlighting the performance of a cooling mechanism in a magnetic trap tailored for excited Rydberg atoms (or molecules) with high magnetic moment. Unlike previous work, the cooling is achieved through fas…

Efficient 2D molasses cooling of a cesium beam using a blue detuned top-hat beam Open

M. Reveillard, Matthieu Viteau, G. Santarelli, Baptiste Battelier, Germain Guiraud , et al. · 2022

Efficient rotational cooling of a cold beam of barium monofluoride Open

Thibault Courageux, Anne Cournol, D. Comparat, B. Viaris de Lesegno, Hans Lignier · 2022

The ability to cool and trap a large number of molecules is currently a crucial challenge for the implementation of various applications in fundamental physics and cold chemistry. We here present an optical cooling of the internal degrees …

Positronium laser cooling in a magnetic field Open

Christian Zimmer, P. Yzombard, A. Camper, D. Comparat · 2021

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 z…

Cesium Rydberg-state ionization study by three-dimensional ion-electron correlation: Toward a monochromatic electron source Open

Raphaël Hahn, A. Trimèche, C. Lopez, D. Comparat, Y. J. Picard · 2021

International audience

Pulsed production of antihydrogen Open

C. Amsler, M. Antonello, Alexander Belov, G. Bonomi, R.S. Brusa , et al. · 2021

Ion and electron ghost imaging Open

A. Trimèche, C. Lopez, D. Comparat, Y. J. Picard · 2020

International audience

Cesium Rydberg states ionization study by 3-D ion-electron correlation Open

Raphaël Hahn, A. Trimèche, C. Lopez, D. Comparat, Y. J. Picard · 2020

We study the excitation and ionization of cesium Rydberg states in an electric field (∼ 2200 V/cm) near the classical field ionization threshold (∼ −280 cm −1 binding energy at this field) by 3-D ionelectron coincidence spectroscopy. Cesiu…

Protocol for pulsed antihydrogen production in the AEḡIS apparatus Open

I.C. Tietje, C. Amsler, M. Antonello, Alexander S. Belov, G. Bonomi , et al. · 2020

The AE ḡ IS collaboration’s main goal is to measure the acceleration of antihydrogen ( ) due to gravity. The experimental scheme is to form a pulsed beam whose vertical deflection is then measured by means of a moir…

Rydberg-positronium velocity and self-ionization studies in a 1T magnetic field and cryogenic environment Open

M. Antonello, Alexander S. Belov, G. Bonomi, R.S. Brusa, M. Caccia , et al. · 2020

We characterized the pulsed Rydberg-positronium production inside the Antimatter Experiment: Gravity, Interferometry, Spectroscopy (AEg¯IS) apparatus in view of antihydrogen formation by means of a charge exchange reaction between cold ant…

Stimulated decay and formation of antihydrogen atoms Open

T. Wolz, C. Malbrunot, Mélissa Vieille-Grosjean, D. Comparat · 2020

Antihydrogen atoms are routinely formed at the Antiproton Decelerator at CERN in a wide range of Rydberg states. To perform precision measurements, experiments rely on ground-state antimatter atoms which are currently obtained only after s…

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