Production of antihydrogen by using the charge exchange reaction, as proposed by AEgIS (Antimatter Experiment: gravity, Interferometry, Spectroscopy), requires the formation of a dense cloud of positronium atoms excited to Rydberg states. In this work, the recent advances in AEgIS towards this result are described. Namely, the manipulation of positrons to produce bunches containing more than 108 particles and the laser excitation of positronium to Rydberg states, using n=3 as intermediate level, are presented.Production of antihydrogen by using the charge exchange reaction, as proposed by AEgIS (Antimatter Experiment: gravity, Interferometry, Spectroscopy), requires the formation of a dense cloud of positronium atoms excited to Rydberg states. In this work, the recent advances in AEgIS towards this result are described. Namely, the manipulation of positrons to produce bunches containing more than 108 particles and the laser excitation of positronium to Rydberg states, using n=3 as intermediate level, are presented.

Defect and diffusion forum/Diffusion and defect data, solid state data. Part A, Defect and diffusion forumMar 24, 20171 citation

Precision measurements with Rydberg atoms (Conference Presentation)

Georg A. Raithel

Optical and Quantum Sensing and Precision Metrology IIMar 27, 20200 citations

Production of long-lived positronium states via laser excitation to 33P level

(The AEgIS collaboration)

The 33P state of positronium is an intermediate level suitable for producing long-lived positronium states. On one hand, it can be used in a two-step laser excitation scheme from the ground state to Rydberg levels. On the other hand, excitation of positronium to 33P level is a simple pathway for producing metastable 23S positronium atoms by spontaneous radiactive decay. In this work, experiments showing the production of such long-lived levels, using the 33P state as intermediate state, are presented. The characteristics of the two long-lived levels, in view of experiments of deflectometry/interferometry with positronium, are discussed.The 33P state of positronium is an intermediate level suitable for producing long-lived positronium states. On one hand, it can be used in a two-step laser excitation scheme from the ground state to Rydberg levels. On the other hand, excitation of positronium to 33P level is a simple pathway for producing metastable 23S positronium atoms by spontaneous radiactive decay. In this work, experiments showing the production of such long-lived levels, using the 33P state as intermediate state, are presented. The characteristics of the two long-lived levels, in view of experiments of deflectometry/interferometry with positronium, are discussed.

AIP conference proceedingsJan 1, 20191 citation

Rydberg atom spectroscopy (A)

S. Haroche

Journal of the Optical Society of America AMay 1, 19780 citations

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

M. Antonello, Alexander S. Belov, G. Bonomi +44 more

We characterized the pulsed Rydberg-positronium production inside the Antimatter Experiment: Gravity, Interferometry, Spectroscopy ( $\mathrm{AE}\overline{\text{g}}\mathrm{IS}$ ) 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 ($\ensuremath{\approx}10\phantom{\rule{0.16em}{0ex}}\mathrm{K}$) and in $1\phantom{\rule{0.16em}{0ex}}\mathrm{T}$ 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 ${n}_{\mathrm{eff}}$ 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.We characterized the pulsed Rydberg-positronium production inside the Antimatter Experiment: Gravity, Interferometry, Spectroscopy ($\mathrm{AE}\overline{\text{g}}\mathrm{IS}$) 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 ($\ensuremath{\approx}10\phantom{\rule{0.16em}{0ex}}\mathrm{K}$) and in $1\phantom{\rule{0.16em}{0ex}}\mathrm{T}$ 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 ${n}_{\mathrm{eff}}$ 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.

arXiv:1911.04342Physical Review AJul 2, 202022 citations

We characterized the pulsed Rydberg-positronium production inside the Antimatter Experiment: Gravity, Interferometry, Spectroscopy (

\mathrm{AE}\overline{\text{g}}\mathrm{IS}

) 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 ($\ensuremath{\approx}10\phantom{\rule{0.16em}{0ex}}\mathrm{K}$) and in

1\phantom{\rule{0.16em}{0ex}}\mathrm{T}

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

{n}_{\mathrm{eff}}

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.