Mixing angle of doubly heavy baryons in QCD

We calculate the mixing angles between the spin-1/2, Xi(bc)-Xi'(bc) and Omega(bc)-Omega'(bc) states of doubly heavy baryons within the QCD sum rules method. It is found that the mixing angles are large and have the values phi(Xi bc) = 16 degrees +/- 5 degrees and phi(Omega bc) = 18 degrees +/- 6 degrees, respectively. The mixing angles are slightly smaller compared to the predictions of the non-relativistic quark model, phi(Xi bc) = 25.5 degrees and phi(Omega bc) = 25.9 degrees.


Radiative Omega(Q)* -> Omega(Q)gamma and Xi(Q)* -> Xi(Q)'gamma transitions in light cone QCD
Alıyev, Tahmasıb; SUNDU PAMUK, HAYRİYE (2015-01-14)
We calculate the magnetic dipole and electric quadrupole moments associated with the radiative Omega(Q)* -> Omega(Q)gamma and Xi(Q)* -> Xi(Q)'gamma transitions with Q = b or c in the framework of light cone QCD sum rules. It is found that the corresponding quadrupole moments are negligibly small, while the magnetic dipole moments are considerably large. A comparison of the results of the considered multi-pole moments as well as corresponding decay widths with the predictions of the vector dominance model is...
Measurement of the Z -> tau tau cross section with the ATLAS detector
Aad, G.; et. al. (2011-12-14)
The Z -> tau tau cross section is measured with the ATLAS experiment at the LHC in four different final states determined by the decay modes of the tau leptons: muon-hadron, electron-hadron, electron-muon, and muon-muon. The analysis is based on a data sample corresponding to an integrated luminosity of 36 pb(-1), at a proton-proton center-of-mass energy of root s = 7 TeV. Cross sections are measured separately for each final state in fiducial regions of high detector acceptance, as well as in the full phas...
Coupling constants g alpha(0)omega gamma and g alpha(0)p gamma as derived from QCD sum rules
Gokalp, A; Yılmaz, Osman (2001-11-01)
We consider the two point correlation function of a scalar current in the QCD sum rule approach to estimate the overlap amplitude of the a(o)-meson. We then employ QCD sum rules to calculate the coupling constants g(omegaaogamma) and g(rhoaogamma) by studying the three point a(o)omegagamma- and a(o)rhogamma-correlation functions.
Mixing angle of hadrons in QCD: A new view
Alıyev, Tahmasıb; Özpineci, Altuğ (American Physical Society (APS), 2011-01-19)
A new method for calculation of the mixing angle between the hadrons within QCD sum rules is proposed. In this method, the mixing is expressed in terms of quark and gluon degrees of freedom. As an application, the detailed calculation of the mixing angle between heavy cascade baryons Xi(Q) and Xi'(Q), Q = c, b is presented and it is found that the mixing angle between Xi(b) (Xi(c)) and Xi'(b) (Xi'(c)) is given by theta(b) = 6.4 degrees +/- 1.8 degrees (theta(c) = 5.5 degrees +/- 1.8 degrees).
Rare B -> l(+)l(-)gamma decay and new physics effects
Alıyev, Tahmasıb; Özpineci, Altuğ; Savcı, Mustafa (2001-11-08)
Using the most general, model independent form of the effective Hamiltonian rare decays B --> l(+)l(-)gamma (l = mu, tau) are studied. The sensitivity of the photon energy distribution and branching ratio to the new Wilson coefficients is investigated.
Citation Formats
T. Alıyev and M. Savcı, “Mixing angle of doubly heavy baryons in QCD,” PHYSICS LETTERS B, pp. 149–151, 2012, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/39349.