The ASACUSA experiment at CERN's AD antiproton decelerator catches antiprotons in helium, where the antiprotons replace electrons, giving exotics atoms.

Patrice Loïez

Published Jul 19, 2000• 0 citations

Abstract

Photo 03: Laser beams are prepared for shooting at antiprotonic helium atoms. Left to right: Masaki Hori (Tokyo University) and John Eades (CERN). Photo 01: Dye laser triggered by "YAG" laser. Photo 02: Masaki Hori adjusting optical system of laser beams.

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The ASACUSA experiment at CERN's AD antiproton decelerator catches antiprotons in helium, where the antiprotons replace electrons, giving exotics atoms.

Patrice Loïez

Published Jul 19, 2000• 0 citations

OpenAlex

Abstract

Related papers

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A semiclassical, many-body atomic model incorporating a momentum-dependent Heisenberg core to stabilize atomic electrons is used to study antiproton capture on helium. Details of the antiproton collisions leading to eventual capture are presented, including the energy and angular-momentum states of incident antiprotons which result in capture via single- or double-electron ionization, i.e., into ${\mathrm{He}}^{2+}$ p\ifmmode\bar\else\textasciimacron\fi{} or ${\mathrm{He}}^{+}$ p\ifmmode\bar\else\textasciimacron\fi{}, and the distribution of energy and angular-momentum states following the Auger cascade. These final states are discussed in light of recently reported anomalously long-lived antiproton states observed in liquid He [Iwasaki et al., Phys. Rev. Lett. 67, 1246 (1991)].A semiclassical, many-body atomic model incorporating a momentum-dependent Heisenberg core to stabilize atomic electrons is used to study antiproton capture on helium. Details of the antiproton collisions leading to eventual capture are presented, including the energy and angular-momentum states of incident antiprotons which result in capture via single- or double-electron ionization, i.e., into ${\mathrm{He}}^{2+}$p\ifmmode\bar\else\textasciimacron\fi{} or ${\mathrm{He}}^{+}$p\ifmmode\bar\else\textasciimacron\fi{}, and the distribution of energy and angular-momentum states following the Auger cascade. These final states are discussed in light of recently reported anomalously long-lived antiproton states observed in liquid He [Iwasaki et al., Phys. Rev. Lett. 67, 1246 (1991)].

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{\mathrm{He}}^{2+}

p\ifmmode\bar\else\textasciimacron\fi{} or

{\mathrm{He}}^{+}

p\ifmmode\bar\else\textasciimacron\fi{}, and the distribution of energy and angular-momentum states following the Auger cascade. These final states are discussed in light of recently reported anomalously long-lived antiproton states observed in liquid He [Iwasaki et al., Phys. Rev. Lett. 67, 1246 (1991)].