LEAP 2013 Uppsala SE

In March 2012 the ALPHA Collaboration reported data from an experiment in which transitions between hyperfine levels of magnetically-trapped ground state antihydrogen atoms were selectively induced and monitored [1]. Those data comprise the first – albeit crude – direct spectroscopic probe of a pure antimatter atom, and mark the advent of an era in which precision comparisons of hydrogen and...

Antihydrogen (¯H) atoms are produced via laser-controlled, two-stage charge exchange in a cryogenic Penning trap. 6x10^6 antiprotons (¯p) and 3x10^8 positrons (e+) are held in a nested well potential structure. Cs* atoms, produced via laser excitation within the cryogenic Penning trap, travel radially across the trap and through the e+ plasma to produce Ps*. The Ps* atoms are produced...

Detailed comparisons of anti-hydrogen with hydrogen promise to be a fruitful test bed of fundamental symmetries such as the CPT Theorem for quantum field theory or　studies of gravitational influence on antimatter. With a string of recent successes, starting　with the first trapped anti-hydrogen and recently resulting in the first measurement of a quantum transition in anti-hydrogen, the ALPHA...

Antiprotons have been proposed as potential modality for particle beam cancer therapy by Gray and Kalogeropoulos in 1985. This proposal was based on the enhancement of physical dose deposition near the end of range due to the annihilation of antiprotons when captured by a nucleus and the expectation of an enhanced RBE of this additional dose. Starting in 2003 the AD-4 collaboration at CERN...

Recently created, very low energy antiprotons are of great interest because of possible formation of ultraslow anti-hydrogen atoms [1,2]. In this work we compute the cross sections and rates of the anti-hydrogen and muonic anti-hydrogen atom three-body formation reactions at low and very low collision energies. The muonic anti-hydrogen is a bound state of an antiproton and a positive muon....

Antihydrogen is now routinely produced at CERN by overlapping clouds of positrons and antiprotons. The mechanisms responsible for antihydrogen formation (radiative capture and the three-body reaction) are both dependent on the temperature of the positrons (T_e), though with a different weight. Here we present a simple model of the behaviour of the positron temperature based on the main...

The ASACUSA CUSP collaboration at the Antiproton Decelerator of CERN is planning to measure the ground-state hyperfine splitting of antihydrogen using an atomic spectroscopy beamline. Antihydrogen is the simplest atom consisting entirely of antimatter. Since its matter counterpart is one of the most precisely measured atoms in physics, a comparison of antihydrogen and hydrogen could provide...

The ASACUSA collaboration has been making a path to realize high precision microwave spectroscopy of ground-state hyperfine splitting of antihydrogen atom in flight for a stringent test of the CPT symmetry. For our physics goal, an efficient extraction of a spin polarized antihydrogen beam is essential. In 2010, we have succeeded in synthesizing our first cold antihydrogen atoms employing a...