DIRAC CollaborationAdeva Andany, BernardoGómez Rodríguez, FaustinoLópez Aguera, María de los ÁngelesPló Casasús, MáximoRomero Vidal, AntonioSantamarina Ríos, CibránSaborido Silva, Juan JoséVázquez Regueiro, PabloZrelov, P.2025-01-302025-01-302004-11-02B Adeva et al 2004 J. Phys. G: Nucl. Part. Phys. 30 19290954-3899https://hdl.handle.net/10347/39312The goal of the DIRAC experiment at CERN is to measure with high precision the lifetime of the π+π− atom (A2π), which is of order 3 × 10−15 s, and thus to determine the s-wave ππ-scattering lengths difference |a0 − a2|. A2π atoms are detected through the characteristic features of π+π− pairs from the atom break-up (ionization) in the target. We report on a first high statistics atomic data sample obtained from p–Ni interactions at 24 GeV/c proton momentum and present the methods to separate the signal from the background.eng2207 Física atómica y nuclearjournal article10.1088/0954-3899/30/12/012open access