English
Related papers

Related papers: Virtual $O(\a_s)$ corrections to the inclusive dec…

200 papers

We calculate the $O(\a_s)$ virtual corrections to the matrix element for $b \to s \gamma$, taking into account the contributions of the four-Fermi operator $O_2$ and the electromagnetic and color dipole-type operators. The results are…

High Energy Physics - Phenomenology · Physics 2011-01-05 C. Greub , T. Hurth , D. Wyler

In this paper we take the first step towards a complete next-to-next-to-leading logarithmic (NNLL) calculation of the inclusive decay rate for $B \to X_s\gamma$. We consider the virtual corrections of order $\alphas^2 n_f$ to the matrix…

High Energy Physics - Phenomenology · Physics 2008-11-26 Kay Bieri , Christoph Greub , Matthias Steinhauser

The calculation of the $O(\a_s)$ virtual corrections to the matrix element of the inclusive decay $b \to s \gamma$ is reported. These contributions drastically reduce the large renormalization scale dependence of the leading logarithmic…

High Energy Physics - Phenomenology · Physics 2007-05-23 Christoph Greub , Tobias Hurth

We present in detail the calculation of the virtual O(alpha_s) corrections to the inclusive semi-leptonic rare decay b --> s l+ l-. We also include those O(alpha_s) bremsstrahlung contributions which cancel the infrared and mass…

High Energy Physics - Phenomenology · Physics 2014-11-17 H. H. Asatryan , H. M. Asatrian , C. Greub , M. Walker

We calculate the virtual and bremsstrahlung fermionic corrections due to the interference of the electro- and chromomagnetic dipole operators in the inclusive \bar{B}\to X_s\gamma decay at O(\alpha_s^2) and present analytical results for…

High Energy Physics - Phenomenology · Physics 2008-11-26 Thorsten Ewerth

We calculate O(alpha_s) two-loop virtual corrections to the differential decay width dGamma(B --> X_s l^+ l^-)/ds, where s is the invariant mass squared of the lepton pair. We also include those contributions from gluon bremsstrahlung which…

High Energy Physics - Phenomenology · Physics 2011-01-05 H. H. Asatryan , H. M. Asatrian , C. Greub , M. Walker

We calculate the set of O(\alpha_s) corrections to the double differential decay width d\Gamma_{77}/(ds_1 \, ds_2) for the process \bar{B} \to X_s \gamma \gamma originating from diagrams involving the electromagnetic dipole operator O_7.…

High Energy Physics - Phenomenology · Physics 2012-07-11 Ahmet Kokulu

We present the calculation of the virtual- and bremsstrahlung corrections of O(alpha_s) to the matrix elements <d l+ l-|O_i|b>. This is the missing piece in the NNLL results for various observables associated with the process B-> X_d l+ l-,…

High Energy Physics - Phenomenology · Physics 2011-01-05 H. M. Asatrian , K. Bieri , C. Greub , M. Walker

We present our results for the NNLL virtual corrections to the matrix elements of the operators O_1 and O_2 for the inclusive process b\to s\ell^+\ell^- in the kinematical region q^2>4m_c^2, where q^2 is the invariant mass squared of the…

High Energy Physics - Phenomenology · Physics 2009-05-20 Christoph Greub , Volker Pilipp , Christof Schüpbach

We calculate the set of O(alpha_s) corrections to the double differential decay width dGamma_77/(ds_1*ds_2) for the process B -> X_s gamma gamma originating from diagrams involving the electromagnetic dipole operator O_7. The kinematical…

High Energy Physics - Phenomenology · Physics 2012-01-23 H. M. Asatrian , C. Greub , A. Kokulu , A. Yeghiazaryan

We present the results of the O(alpha_s) two-loop virtual corrections to the differential decay width dGamma(B -> X_s l+ l-)/ds, where s is the invariant mass squared of the lepton pair. Those contributions from gluon bremsstrahlung which…

High Energy Physics - Phenomenology · Physics 2007-05-23 C. Greub , M. Walker

The flavor-changing electromagnetic dipole operator O_7 gives the dominant contribution to the B -> Xs gamma decay rate. We calculate two-loop QCD corrections to its matrix element together with the corresponding bremsstrahlung…

High Energy Physics - Phenomenology · Physics 2013-07-02 I. Blokland , A. Czarnecki , M. Misiak , M. Slusarczyk , F. Tkachov

We compute three-loop vertex corrections to $b\to s\gamma$ induced by current-current operators. The results are presented as expansions in $m_c/m_b$ with numerical coefficients which allow to cover all relevant values for the heavy quark…

High Energy Physics - Phenomenology · Physics 2023-12-11 Matteo Fael , Fabian Lange , Kay Schoenwald , Matthias Steinhauser

In this analysis, we present the contribution associated with the chromomagnetic dipole operator O_8 to the double differential decay width d\Gamma/(ds_1 ds_2) for the inclusive process $\bar{B} \to X_s \gamma \gamma$. The kinematical…

High Energy Physics - Phenomenology · Physics 2016-02-01 H. M. Asatrian , C. Greub , A. Kokulu

The order $\alpha_s$ corrections to the Wilson coefficients of the dipole operators ($O_7,O_8$) at the matching scale $\mu =m_W$ are a crucial ingredient for a complete next- to-leading logarithmic calculation of the branching ratio for $b…

High Energy Physics - Phenomenology · Physics 2014-11-17 Christoph Greub , Tobias Hurth

We evaluate non factorizable $O(\alpha\alpha_s)$ corrections to the process $Z\to b\bar{b}$ due to the virtual t-quark. All two-loop vertex diagrams with $W$'s and charged ghosts $\Phi$'s are included. They are evaluated in the large…

High Energy Physics - Phenomenology · Physics 2009-10-31 J. Fleischer , F. Jegerlehner , M. Tentyukov , O. Veretin

We compute the O(alpha_s) corrections to the Wilson coefficients of the dimension five operators emerging from the Operator Product Expansion of inclusive radiative B decays. We discuss the impact of the resulting O(alpha_s…

High Energy Physics - Phenomenology · Physics 2010-02-15 Thorsten Ewerth , Paolo Gambino , Soumitra Nandi

We briefly discuss the status of the NNLL QCD calculations in the inclusive rare B decay $B \to X_s \ell^+ \ell^-$. Two important ingredients, the two-loop matrix elements of the four quark operator ${\cal O}_2$ and the bremsstrahlung…

High Energy Physics - Phenomenology · Physics 2009-11-07 A. Ghinculov , T. Hurth , G. Isidori , Y. -P. Yao

We calculate the O($\alpha_s$) gluon Bremsstrahlung corrections to the inclusive decay $b \rightarrow s \gamma$, involving the full operator basis $\hat O_1$ -- $\hat O_8$. Confirming and extending earlier calculations of Ali and Greub, we…

High Energy Physics - Phenomenology · Physics 2009-10-28 Nicolas Pott

In these proceedings, we briefly review the individual interference contribution of the electromagnetic dipole operator $\mathcal{O}_{7}$ to the double differential decay width $d\Gamma_{77}/(ds_1\, ds_2)$ for the process $\bar{B} \to X_s…

High Energy Physics - Phenomenology · Physics 2015-06-23 Ahmet Kokulu
‹ Prev 1 2 3 10 Next ›