AIP conference proceedings

Cryogenic Particle Accumulation In ATRAP And The First Antihydrogen Production Within A Magnetic Gradient Trap For Neutral Antimatter

C. H. Storry, Adam C. Carew, D. Comeau, Eric A. Hessels, M. Weel, M. C. George, D. Grzonka, W. Oelert, T. Sefzick, Z. Zhang, G. Gabrielse, P. Larochelle, D. LeSage, B. Levitt, W. S. Kolthammer, Robert McConnell, Philip Richerme, Jonathan Wrubel, Andrew J. Speck, Frank Markert, F. Nillius, Martin Scheid, J. Walz, Yasuyuki Kanai, Y. Yamazaki

Published Jan 1, 2008• 1 citation

Publisher

Abstract

ATRAP has made many important improvements since CERN's Antiproton Decelerator (AD) was restarted in 2006. These include substantial increases in the number of positrons (e+) and antiprotons (Pbars) used to make antihydrogen (Hbar) atoms, a new technique for loading electrons (e−) that are used to cool Pbars and e+, implementation of a completely new, larger and more robust apparatus in our second experimental zone and the inclusion of a quadrupole Ioffe trap intended to trap the coldest Hbar atoms produced. Using this new apparatus we have produced large numbers of Hbar atoms within a Penning trap that is located within this quadrupole Ioffe trap using a new technique which shows promise for producing even colder atoms. These observed Hbar atoms resolve a debate about whether positrons and antiprotons can be brought together to form atoms within the divergent magnetic fields of a quadrupole Ioffe trap.

DOI: 10.1063/1.2977845

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