M. Augsburger

Measurement of the strong interaction parameters in antiprotonic hydrogen and probable evidence for an interference with inner bremsstrahlung

Abstract The spin-averaged values of the 1s strong interaction parameters in antiprotonic hydrogen were measured with good statistics. The results are: shift (ϵ 1s ) = −712.5 ± 20.3 eV and width (Γ 1s ) = 1054± 65 eV . These values are compatible and have approximately the same precision as the world average before this experiment. With some additional constraints, both the triplet and singlet components could be extracted from the same spectrum. The results are: 3 S 1 shift: −785 ± 35 eV , 3 S 1 width: 940 ± 80 eV , 1 S 0 width: 1200 ± 250 eV . In addition, precise values for the K α L α and Ltotal L α yields at low pressure (20 mbar) were obtained: 0.0176 ± 0.0016 and 1.45 ± 0.05 . Furthermore, the 2p mean absorption width of 30.8 ± 3.0 meV was deduced, also compatible with and of similar precision as the world average before this experiment. An indication of interference between the measured Lyman (Ki) x-ray series and the process of inner bremsstrahlung due to charged meson production after annihilation was seen because of the low background conditions of this experiment.

Measurement of the strong interaction parameters in antiprotonic deuterium

Abstract Antiprotonic deuterium K α X-rays were seen for the first time. Their analysis resulted in spin-averaged 1s strong interaction parameters, namely −1050±250 eV (repulsive) for the 1s shift and 1100±750 eV for the 1s width. The large errors are mainly due to low statistics. In addition, values for the K α /L α and L total /L α yields at low pressure (20 mbar) were obtained: 0.005±0.003 and 1.34±0.05. Furthermore, a 2p mean absorption width of 80 ≤ Γ 2p ≤ 350 meV was deduced. The results for the 1s ground state are somewhat surprising, especially the narrow 1s width which is similar to the spin-averaged antiprotonic hydrogen 1s width. However, our 1s width is in agreement with low-energy scattering data [A. Zenoni et al., Phys. Lett. B 461 (1999) 413] (see preceding paper).

High resolution X ray spectroscopy in light antiprotonic atoms

AbstractAt the LEAR facility, CERN, antiprotonic Lα transitions in light elements have been investigated with a focussing crystal spectrometer. The high resolution of the experiment allowed for the first time to resolve in

Protonium X-ray spectroscopy

{\bar p}

Charged Pion Mass Determination and Energy — Calibration Standards Based on Pionic X-ray Transitions

H the 23P0 state from the close lying states 23P2, 21P1, and 23P1. In

Precision determination of pion mass using x-ray CCD spectroscopy

{\bar p}