Doubly charmful baryonic B decays

Journal Article · Sat Apr 01 00:00:00 EST 2006 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.73.074015· OSTI ID:20782811

Cheng, H -Y; Chua, C -K; Tsai, S -Y ^[1]

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1. Institute of Physics, Academia Sinica Taipei, Taiwan 115 (China)

There are two apparent puzzles connected with the two-body and three-body doubly charmed baryonic B decays. First, earlier calculations based on QCD sum rules or the diquark model predict B(B{sup 0}{yields}{xi}{sub c}{sup +}{lambda}{sub c}{sup -}){approx_equal}B(B{sup 0}{yields}B{sub c}N), while experimentally the former has a rate 2 orders of magnitude larger than the latter. Second, a naive estimate of the branching ratio O(10{sup -9}) for the color-suppressed three-body decay B{yields}{lambda}{sub c}{sup +}{lambda}{sub c}{sup -}K, which is highly suppressed by phase space, is too small by 5 to 6 orders of magnitude compared to the experiment. We show that the great suppression for the {lambda}{sub c}{sup +}{lambda}{sub c}{sup -}K production can be alleviated provided that there exists a narrow hidden charm bound state with a mass near the {lambda}{sub c}{lambda}{sub c} threshold. This new state that couples strongly to the charmed baryon pair can be searched for in B decays and in pp collisions by studying the mass spectrum of D{sup (*)}D{sup (*)} or {lambda}{sub c}{lambda}{sub c}. The doubly charmful decay B{yields}{xi}{sub c}{lambda}{sub c} has a configuration more favorable than the singly charmful one such as B{sup 0}{yields}{lambda}{sub c}p since no hard gluon is needed to produce the energetic {xi}{sub c}{lambda}{sub c} pair in the former decay, while two hard gluons are needed for the latter process. Assuming that a soft qq quark pair is produced through the {sigma} and {pi} meson exchanges in the configuration for B{yields}{xi}{sub c}{lambda}{sub c}, it is found that its branching ratio is of order 10{sup -3}, in agreement with the experiment.

• OSTI ID: 20782811
• Journal Information: Physical Review. D, Particles Fields, Vol. 73, Issue 7; Other Information: DOI: 10.1103/PhysRevD.73.074015; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BOUND STATE
BRANCHING RATIO
COLOR MODEL
D MESONS
D*-2010 MESONS
GLUONS
KAONS
LAMBDA C PLUS BARYONS
MASS SPECTRA
PARTICLE DECAY
PHASE SPACE
PIONS
PROTON-PROTON INTERACTIONS
QUANTUM CHROMODYNAMICS
QUARKS
REST MASS
SUM RULES
THREE-BODY PROBLEM
TWO-BODY PROBLEM