TY  - JOUR
AU  - Aceti, F.
AU  - Dai, L. R.
AU  - Oset, E.
PY  - 2016
DA  - 2016//
TI  - a(1)(1420) peak as the pi f(0)(980) decay mode of the a(1)(1260)
T2  - Phys. Rev. D
JO  - Physical Review D
SP  - 096015
EP  - 9pp
VL  - 94
IS  - 9
PB  - Amer Physical Soc
AB  - We study the decay mode of the a(1)(1260) into a pi(+) in p wave and the f(0)(980) that decays into pi(+)pi(-) in s wave. The mechanism proceeds via a triangular mechanism where the a(1)(1260) decays into K*K-, the K* decays to an external pi(+) and an internal K that fuses with the (K) over bar producing the f(0)(980) resonance. The mechanism develops a singularity at a mass of the a(1)(1260) around 1420 MeV, producing a peak in the cross section of the pp reaction, used to generate the mesonic final state, which provides a natural explanation of all the features observed in the COMPASS experiment, where a peak observed at this energy is tentatively associated to a new resonance called a(1)(1420). On the other hand, the triangular singularity studied here gives rise to a remarkable feature, where a peak is seen for a certain decay channel of a resonance at an energy about 200 MeV higher than its nominal mass.
SN  - 2470-0010
UR  - http://arxiv.org/abs/1606.06893
UR  - https://doi.org/10.1103/PhysRevD.94.096015
DO  - 10.1103/PhysRevD.94.096015
LA  - English
N1  - WOS:000388824300007
ID  - Aceti_etal2016
ER  -