PT Journal
AU Liang, WH
   Sakai, S
   Xie, JJ
   Oset, E
TI Triangle singularity enhancing isospin violation in (B)over-bar(s)(0)-> J/psi pi(0)f(0)(980)
SO Chinese Physics C
JI Chin. Phys. C
PY 2018
BP 044101
EP 9pp
VL 42
IS 4
DI 10.1088/1674-1137/42/4/044101
LA English
DE triangle singularity; light scalar meson; isospin violation; bottom meson decay
AB We perform calculations for the (B) over bar (0)(s)-> J/psi pi(0)f(0)(980) and (B) over bar (0)(s)-> J/psi pi(0)a(0)(980) reactions, showing that the first is isospin-suppressed while the second is isospin-allowed. The reaction proceeds via a triangle mechanism, with (B) over bar (0)(s)-> J/psi K*(K) over bar +c.c., followed by the decay K*-> K pi and a further fusion of K (K) over bar into the f(0)(980) or a(0)(980). We show that the mechanism develops a singularity around the pi(0)f(0)(980) or pi(0)a(0)(980) invariant mass of 1420 MeV, where the pi(0)f(0) and pi(0)a(0) decay modes are magnified and also the ratio of pi(0)f(0) to pi(0)a(0) production. Using experimental information for the (B) over bar (0)(s)-> J/psi K*(K) over bar +c.c. decay, we are able to obtain absolute values for the reactions studied which fall into the experimentally accessible range. The reactions proposed and the observables evaluated, when contrasted with actual experiments, should be very valuable to obtain information on the nature of the low lying scalar mesons.
ER