Amplitude analysis of the D+→ π-π+π+ decay and measurement of the π-π+ S-wave amplitude

作者：Aaij, R.; Abdelmotteleb, A. S. W.; Beteta, C. Abellan; Abudinen, F.; Ackernley, T.; Adeva, B.; Adinolfi, M.; Afsharnia, H.; Agapopoulou, C.; Aidala, C. A.; Aiola, S.; Ajaltouni, Z.; Akar, S.; Akiba, K.; Albrecht, J.; Alessio, F.; Alexander, M.; Alfonso Albero, A.; Aliouche, Z.; Cartelle, P. Alvarez; Amalric, R.; Amato, S.; Amey, J. L.; Amhis, Y.; An, L.; Anderlini, L.; Andersson, M.; Andreianov, A.; Andreotti, M.; Andreou, D.; Ao, D.; Archilli, F.; Artamonov, A.; Artuso, M.; Aslanides, E.

来源：JOURNAL OF HIGH ENERGY PHYSICS, 2023, (6): 44.

DOI：10.1007/JHEP06(2023)044

• Charm Physics
• Hadron-Hadron Scattering
• Particle and Resonance Production

An amplitude analysis of the D+-> (-)pi(+)pi(+) decay is performed with a sample corresponding to 1.5 fb(-1) of integrated luminosity of pp collisions at a centre-of-mass energy root s = 8 TeV collected by the LHCb detector in 2012. The sample contains approximately six hundred thousand candidates with a signal purity of 95%. The resonant structure is studied through a fit to the Dalitz plot where the pi(-)pi(+) S-wave amplitude is extracted as a function of pi(-)pi(+) mass, and spin-1 and spin-2 resonances are included coherently through an isobar model. The S-wave component is found to be dominant, followed by the rho(770)(0)pi(+) and f(2)(1270)pi(+) components. A small contribution from the omega(782) -> pi(-)pi(+) decay is seen for the first time in the D+-> pi(-)pi(+)pi(+) decay.