Physics – Nuclear Physics – Nuclear Theory
Scientific paper
2005-03-10
Phys.Rev. C72 (2005) 035201
Physics
Nuclear Physics
Nuclear Theory
51 pages, 8 figures, submitted to Physical Review C
Scientific paper
10.1103/PhysRevC.72.035201
The semileptonic decays of Lambda_c and Lambda_b are treated in the framework of a constituent quark model. Both nonrelativistic and semirelativistic Hamiltonians are used to obtain the baryon wave functions from a fit to the spectra, and the wave functions are expanded in both the harmonic oscillator and Sturmian bases. The latter basis leads to form factors in which the kinematic dependence on q^2 is in the form of multipoles, and the resulting form factors fall faster as a function of q^2 in the available kinematic ranges. As a result, decay rates obtained in the two models using the Sturmian basis are significantly smaller than those obtained using the harmonic oscillator basis. In the case of the Lambda_c, decay rates calculated using the Sturmian basis are closer to the experimentally reported rates. However, we find a semileptonic branching fraction for the Lambda_c to decay to excited Lambda* states of 11% to 19%, in contradiction with what is assumed in available experimental analyses. Our prediction for the Lambda_b semileptonic decays is that decays to the ground state Lambda_c provide a little less than 70% of the total semileptonic decay rate. For the decays Lambda_b to Lambda_c, the analytic form factors we obtain satisfy the relations expected from heavy-quark effective theory at the non-recoil point, at leading and next-to-leading orders in the heavy-quark expansion. In addition, some features of the heavy-quark limit are shown to naturally persist as the mass of the heavy quark in the daughter baryon is decreased.
Capstick Simon
Pervin Muslema
Roberts Winston
No associations
LandOfFree
Semileptonic Decays of Heavy Lambda Baryons in a Quark Model does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Semileptonic Decays of Heavy Lambda Baryons in a Quark Model, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Semileptonic Decays of Heavy Lambda Baryons in a Quark Model will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-685835