Determination of pi pi scattering lengths from measurement of pi(+)pi(-) atom lifetime

作者：Adeva B; Afanasyev L; Benayoun M; Benelli A; Berka Z; Brekhovskikh V; Caragheorgheopol G; Cechak T; Chiba M; Chliapnikov P V; Ciocarlan C; Constantinescu S; Costantini S; Curceanu C; Doskarova P; Dreossi D; Drijard D^*; Dudarev A; Ferro Luzzi M; Fungueirino Pazos J L; Gallas Torreira M; Gerndt J; Gianotti P; Goldin D; Gomez F; Gorin A; Gorchakov O; Guaraldo C; Gugiu M; Hansroul M; Hons Z; Hosek R; Iliescu M

来源：Physics Letters B, 2011, 704(1-2): 24-29.

DOI：10.1016/j.physletb.2011.08.074

• DIRAC experiment
• Elementary atom
• Pionium atom
• Pion scattering

The DIRAC experiment at CERN has achieved a sizeable production of pi(+)pi(-) atoms and has significantly improved the precision on its lifetime determination. From a sample of 21 227 atomic pairs, a 4% measurement of the S-wave pi pi scattering length difference |a(0) - a(2)| = (0.2533(-0.0078)(+0.0080)|stat(-0.0073)(+0.0078)|syst)M-pi+(-1) has been attained, providing an important test of Chiral Perturbation Theory.

• 出版日期2011-10-5