collaboration © 2007
Measurement of the strong interaction width and shift of the ground state
- Precise determination of the pion-nucleon scattering lengths.
- Extraction of the pion-nucleon coupling constant and the pion-nucleon σ-term.
- The pionic deuterium level shift reveals isospin breaking effects by constraining the scattering lengths as obtained from pionic hydrogen.
- The pionic deuterium ground state width is dominated by true absorption and directly related to pion production strength α at threshold.
- To measure the strong interaction width Γ and shift ε of the ground state
of pionic hydrogen with high precision better than 1% for the shift and about 2% for the width.
- Use the PSI cyclotron trap to produce pionic atoms in a controlled environment.
- Use crystal spectrometers and CCD detectors to measure precisely the X-ray energies and line shapes.
- Perform measurements at different hydrogen densities.
- Perform measurements for different transitions.
- Perform measurements of muonic hydrogen to quantify the Doppler broadening of X-ray lines from Coulomb explosion.
- Correlate cascade theory to the Doppler broadening corrections.
Atomic cascade in pionic hydrogen:
||Γ1s / meV
||α / μb
||+ 7120 ± 10
||823 ± 19
||- 2356 ± 31
Last Modified: Friday February 24, 2012 03:02