On the binding energies of antihydrogen formed by the interactions of antiprotons in cold positron plasmas

The binding energies of antihydrogen atoms formed when antiprotons are mixed with positron plasmas having densities ranging from 1013–1015 m−3, and at temperatures of 5–30 K, have been investigated using simulations. Major changes in the distribution of binding energies are observed, with more strongly bound states evident at the higher densities, and at lower temperatures. For deeper binding, the distribution of binding energies follows a power-law which is found to be strongly dependent upon plasma properties and the strength of the applied magnetic field. The underpinning role of collisions in determining the binding energies is explored.

[1]  The Alpha Collaboration.  Investigation of the fine structure of antihydrogen , 2020 .

[2]  N. Madsen,et al.  Ion generation and loading of a Penning trap using pulsed laser ablation , 2020, New Journal of Physics.

[3]  F. Robicheaux,et al.  Scaling behaviour of the ground-state antihydrogen yield from CTMC simulation as a function of positron density and temperature , 2019, 1905.03242.

[4]  M. Charlton,et al.  On the formation of trappable antihydrogen , 2018 .

[5]  C. J. Baker,et al.  Antihydrogen accumulation for fundamental symmetry tests , 2017, Nature Communications.

[6]  D. P. Werf,et al.  The role of antihydrogen formation in the radial transport of antiprotons in positron plasmas , 2017 .

[7]  B. Radics,et al.  Antihydrogen level population evolution: impact of positron plasma length , 2016, 1905.03281.

[8]  A. Zhmoginov,et al.  An improved limit on the charge of antihydrogen from stochastic acceleration , 2016, Nature.

[9]  M. Charlton,et al.  Physics with antihydrogen , 2015 .

[10]  A. Zhmoginov,et al.  An experimental limit on the charge of antihydrogen , 2014, Nature Communications.

[11]  John W. V. Storey,et al.  The ALPHA antihydrogen trapping apparatus , 2014 .

[12]  N. Madsen,et al.  Antihydrogen trapping assisted by sympathetically cooled positrons , 2013 .

[13]  J. Wurtele,et al.  Resonant quantum transitions in trapped antihydrogen atoms , 2012, Nature.

[14]  M C George,et al.  Trapped Antihydrogen in Its Ground State , 2012 .

[15]  Berkeley,et al.  Confinement of antihydrogen for 1,000 seconds , 2011, 1104.4982.

[16]  J. Wurtele,et al.  Search For Trapped Antihydrogen , 2010, 1012.4110.

[17]  J. Wurtele,et al.  Trapped antihydrogen , 2010, Nature.

[18]  M. Charlton,et al.  Simulation of the formation of antihydrogen in a nested Penning trap: effect of positron density , 2009 .

[19]  F. Robicheaux.  Atomic processes in antihydrogen experiments: a theoretical and computational perspective , 2008 .

[20]  D. Dubin,et al.  Antihydrogen formation from antiprotons in a pure positron plasma , 2009 .

[21]  G. Gabrielse,et al.  New interpretations of measured antihydrogen velocities and field ionization spectra. , 2006, Physical review letters.

[22]  M. Charlton,et al.  The route to ultra-low energy antihydrogen , 2004 .

[23]  B. Granger,et al.  Strongly magnetized antihydrogen and its field ionization. , 2004, Physical review letters.

[24]  W. Itano,et al.  Sympathetically cooled and compressed positron plasma , 2003 .

[25]  A. Fontana,et al.  Production and detection of cold antihydrogen atoms , 2002, Nature.

[26]  J. N. Tan,et al.  First positron cooling of antiprotons. , 2001 .

[27]  A. Wolf,et al.  Production of antihydrogen by recombination of \barp with e+: What can we learn from electron--ion collision studies? , 1997 .

[28]  M. Glinsky,et al.  Guiding center atoms: Three‐body recombination in a strongly magnetized plasma , 1991 .

[29]  J. Boulmer,et al.  Collisional-radiative recombination in cold plasmas , 1975 .

[30]  J. Keck,et al.  MONTE CARLO TRAJECTORY CALCULATIONS OF ATOMIC EXCITATION AND IONIZATION BY THERMAL ELECTRONS. , 1969 .

[31]  R. C. Stabler,et al.  Electron-Ion Recombination by Collisional and Radiative Processes , 1962 .