TY  - JOUR
AU  - Molina, R.
AU  - Oset, E.
PY  - 2020
DA  - 2020//
TI  - Triangle singularity in B- ->K- X(3872); X ->pi 0 pi+ pi- and the X(3872) mass
T2  - Eur. Phys. J. C
JO  - European Physical Journal C
SP  - 451
EP  - 9pp
VL  - 80
IS  - 5
PB  - Springer
AB  - We evaluate the contribution to the X(3872) width from a triangle mechanism in which the X decays into D0D<overbar></mml:mover>0-cc, then the D0(D<overbar></mml:mover>0) decays into D0 pi 0 (D<overbar></mml:mover>0 pi 0) and the D0D<overbar></mml:mover>0 fuse to produce pi+pi-. This mechanism produces an asymmetric peak from a triangle singularity in the pi+pi- invariant mass with a shape very sensitive to the X mass. We evaluate the branching ratios for a reaction where this effect can be seen in the B--> K-pi 0 pi+pi- reaction and show that the determination of the peak in the invariant mass distribution of pi <mml:mo>+pi <mml:mo>- is all that is needed to determine the X mass. Given the present uncertainties in the X mass, which do not allow to know whether the D<mml:mo>0<mml:mover accent="true">D<mml:mo stretchy="false"><overbar></mml:mover>0 state is bound or not, measurements like the one suggested here should be most welcome to clarify this issue.
SN  - 1434-6044
UR  - https://arxiv.org/abs/2002.12821
UR  - https://doi.org/10.1140/epjc/s10052-020-8014-7
DO  - 10.1140/epjc/s10052-020-8014-7
LA  - English
N1  - WOS:000546996400004
ID  - Molina+Oset2020
ER  -