Lifetime of doubly charmed baryons

Introduction Formulation for Lifetimes of Evaluation of Hadronic Matrix Elements Numerical Results Summary

Chao-Hsi Chang(ITP), Tong Li(NKU), Xue-Qian Li(NKU), Yu-Ming Wang(NKU)

Introduction (ccd) observed by SELEX Collaboration at FERMILA

B (PRL89,112001(2002)) Previous works on doubly heavy-quark baryon (PRD60,014007(1999); hep-ph/9912424; Eur.Phys.J.C9,213(1999)) WE/WA and PI mechanism(PLB280,271(1992); PLB293,430(199

2); Nucl.Phys.B399,441(1993)) Hadronic wave function

Formulation for Lifetimes of The general formula for inclusive decay width

(lifetime): optical theorem

OPE of matrix element

Spectator contribution can be decomposed into two components:

Spectator Contribution

The semileptonic and nonleptonic decay of spectator contribution have been calculated by many authors. (Bigi et al., hep-ph/9401298; PRD56,2783(1997); PRD64,014003(2001))

The total decay width can be decomposed into two parts:

Non-spectator Contribution

Effective Lagrangian

Our calculation includes CKM-suppressed contribution.

The inclusive decays of (ccd)

The inclusive decays of (ccu)

The inclusive decays of (ccs)

Sandwiching the operators between initial and final states of forward scattering, we obtain the hadronic matrix elements:

Hadronic Matrix Elements

Harmonic oscillator wave function

The decay widths

Numerical Results Input parameters

(PRD60,014007(1999); hep-ph/9912424; Eur.Phys.J.C9,213(1999))

reflects the coupling of the two c quarks, we adopt the parameter the same as J/ψ reflects the coupling of two c quarks and the

light quark (u, d, s), we adopt the parameter the same as D meson

Non-perturbative parameters

Compare with other work

Lifetime of Lifetime of Lifetime of strongly depend on the wavefunction at the origin. hep-ph/9912424

Summary

Doubly charmed baryons Inclusive decay width

optical theorem, OPE, WE/WA and PI mechanism

Others (wave functions, other doubly heavy-quark baryons, triply heavy-quark baryon……)

Thank You!