Zobrazeno 1 - 10
of 43
pro vyhledávání: '"Ahmady, Mohammad R."'
Autor:
Ahmady, Mohammad R.
The light-front wavefunction for mesons predicted by holographic light-front QCD is used to obtain the light-cone distribution amplitudes for the light vector mesons and the transition form factors for B and $B_s$ decays to $\rho$, $K^*$ and $\phi$ m
Externí odkaz:
http://arxiv.org/abs/2001.00266
Autor:
Ahmady, Mohammad R., Chishtie, Farrukh
Publikováno v:
Int.J.Mod.Phys. A20 (2005) 6229-6240
The extra contributions due to an extra generation of vector-like quarks to the isospin symmetry breaking observable associated with the radiative B->K^* \gamma decay is obtained. It is shown that this additional contribution is sensitive to the nonu
Externí odkaz:
http://arxiv.org/abs/hep-ph/0508105
Autor:
Ahmady, Mohammad R., Chishtie, Farrukh
The tree level FCNC due to the presence of an additional generation of vector quarks result in the leading order nonspectator contributions to rare B-> K^*+photon decay mode. These tree level contributions are sensitive only to b-> s nonunitary param
Externí odkaz:
http://arxiv.org/abs/hep-ph/0507114
Publikováno v:
Phys.Rev.D64:054011,2001
We investigate the leading effects of extending the Standard Model of electroweak interactions by an extra iso-singlet up- and down- type quark pair on various distributions and total branching ratio of the inclusive B-> X_s l^+ l^- (l =e,\mu) rare B
Externí odkaz:
http://arxiv.org/abs/hep-ph/0105049
Autor:
Ahmady, Mohammad R., Elias, Victor
The nonperturbative content of the QCD vacuum permits the occurrence of QCD-vaccum condensate contributions to penguin amplitudes. We calculate the dimension-4 $$ and $<\alpha_s G^2>$ contributions to the effective Wilson coefficients for
Externí odkaz:
http://arxiv.org/abs/hep-ph/9908375
Autor:
Ahmady, Mohammad R.
Publikováno v:
Phys.Rev. D61 (2000) 077503
We examine our previous conjecture that the eta' intermediate resonance has the dominant role in the long distance contributions to B decay into two photons and a strange final state hadron. We calculate the branching ratio of the exclusive B-> K eta
Externí odkaz:
http://arxiv.org/abs/hep-ph/9908277
Autor:
Ahmady, Mohammad R., Elias, Victor
Publikováno v:
Phys.Rev. D60 (1999) 074013
We calculate the leading nonperturbative contributions to the effective Wilson coefficient of the four-fermion operators arising from the QCD penguin, and we demonstrate how the usual perturbative one loop contribution is augmented by nonperturbative
Externí odkaz:
http://arxiv.org/abs/hep-ph/9901232
Autor:
Ahmady, Mohammad R., Kou, Emi
Publikováno v:
Phys.Rev. D59 (1999) 054014
We calculate the branching ratio and direct CP asymmetry in nonleptonic two body B decays B^+- ->\pi^+- \eta'. It is shown that the tree diagram and gluon fusion mechanism via penguin diagram have comparable contributions to these decays which, as a
Externí odkaz:
http://arxiv.org/abs/hep-ph/9807398
Publikováno v:
Phys.Rev. D57 (1998) 7034-7036
We investigate the momentum dependence of the g*-g-eta' vertex form factor in the presence of the nonperturbative QCD vacuum condensate. The behaviour of this form factor is crucial for, among other things, some proposed mechanisms devised to explain
Externí odkaz:
http://arxiv.org/abs/hep-ph/9801447
Autor:
Ahmady, Mohammad R., Kou, Emi
Publikováno v:
Eur.Phys.J.C1:243-246,1998
We calculate the inclusive decays $B\to X_s\psi$ and $B\to X_s\eta_c$ using factorization assumption. To investigate the bound state effect of the decaying B meson in these inclusive decays we take into account the motion of the $b$ quark using a Gau
Externí odkaz:
http://arxiv.org/abs/hep-ph/9701224