QCD sum rules for the double ratio (f_{Bs}/f_{Bd}/(f_{Ds}/ f_{Dd}) in HQET
Abstract
The double ratio (f_{Bs}/f_{Bd})/ (f_{Ds}/f_{Dd}) is calculated by QCD sum rules in heavy quark effective theory (HQET), both numerically and analytically. Our expression for the double ratio shows explicitly the dependence on the light quark masses, the heavy quark symmetry breaking and the vacuum condensates. The numerical result favors the double ratio to be a little greater than 1.
 Publication:

Physics Letters B
 Pub Date:
 February 1997
 DOI:
 10.1016/S03702693(96)014712
 arXiv:
 arXiv:hepph/9610227
 Bibcode:
 1997PhLB..391..451H
 Keywords:

 High Energy Physics  Phenomenology
 EPrint:
 11 pages, latex file with one figure not included, to appear in Phys.Lett.B