ZEU-THEO

Latest additions:
2017-09-19
10:04
OpenAccess [PUBDB-2017-10870] Report/Journal Article
; ; ; et al
The two-loop electroweak bosonic corrections to $\sin^2\theta_{\textrm{eff}}^{\textrm{b}}$
[DESY-16-119; KW-16-002; arXiv:1607.08375] ddc:530
The prediction of the effective electroweak mixing angle $\sin^2\theta_{\rm eff}^{\rm b}$ in the Standard Model at two-loop accuracy has now been completed by the first calculation of the bosonic two-loop corrections to the $Z{\bar b}b$ vertex. Numerical predictions are presented in the form of a fitting formula as function of $M_Z, M_W, M_H, m_t$ and $\Delta{\alpha}$, ${\alpha_{\rm s}}$. [...]
OpenAccess: Download fulltextPDF Download fulltextPDF (PDFA);

Detailed record - Similar records
2017-08-01
11:08
arXiv [PUBDB-2017-08782] Report/Journal Article
; ; ; et al
Parton distribution functions, $\alpha_s$, and heavy-quark masses for LHC Run II
[DESY-16-179, DO-TH-16-13, arXiv:1701.05838] ddc:530
We determine a new set of parton distribution functions (ABMP16), the strong coupling constant $\alpha_s$ and the quark masses $m_c$, $m_b$ and $m_t$ in a global fit to next-to-next-to-leading order (NNLO) in QCD. The analysis uses the $\overline{MS}$ scheme for $\alpha_s$ and all quark masses and is performed in the fixed-flavor number scheme for $n_f = 3, 4, 5$. [...]
Restricted: Download fulltextPDF Download fulltextPDF (PDFA);

Detailed record - Similar records
2017-07-17
10:46
DBCoverage [PUBDB-2017-07732] Journal Article
; ; ; et al
The three-loop splitting functions P q g ( 2 ) and P g g ( 2 , N F )
ddc:530
Restricted: Download fulltextPDF Download fulltextPDF (PDFA);

Detailed record - Similar records
2017-07-03
14:52
OpenAccess [PUBDB-2017-06699] Report/Journal Article
;
Photon radiation in $e^+e^-\to$ hadrons at low energies with carlomat_3.1
[DESY-17-001; HU-EP-17-01; arXiv:1701.01837] ddc:530
We present a sample of results for the cross sections of several processes of low energetic $e^+e^-$ annihilation into final states containing pions accompanied by one or two photons, or a light lepton pair. The results, which have been obtained with a new version of a multipurpose Monte Carlo program CARLOMAT, labelled 3.1, demonstrate new capabilities of the program which, among others, include a possibility of taking into account either the initial or final state radiation separately, or both at a time, and a possibility of inclusion of the electromagnetic charged pion form factor for processes with charged pion pairs. [...]
OpenAccess: Download fulltextPDF Download fulltextPDF (PDFA);

Detailed record - Similar records
2017-06-19
13:43
OpenAccess [PUBDB-2017-05452] Report/Journal Article
; ;
On ${\gamma }_{5}$ in higher-order QCD calculations and the NNLO evolution of the polarized valence distribution
[DESY-15-061; NIKHEF-15-018; LTH-1042; arXiv:1506.04517] ddc:530
We discuss the prescription for the Dirac matrix ${\gamma }_{5}$ in dimensional regularization used in most second- and third-order QCD calculations of collider cross sections. We provide an alternative implementation of this approach that avoids the use of an explicit form of ${\gamma }_{5}$ and of its (anti-) commutation relations in the most important case of no more than one ${\gamma }_{5}$ in each fermion trace. [...]
OpenAccess: Download fulltextPDF Download fulltextPDF (PDFA);

Detailed record - Similar records
2017-06-14
14:42
OpenAccess [PUBDB-2017-04944] Report/Journal Article
; ; ; et al
Asymptotic 3-loop heavy flavor corrections to the charged current structure functions $F^{W^{+}-W^{-}}_{L}(x,Q^{2})$ and $F^{W^{+}-W^{-}}_{2}(x,Q^{2})$
[DESY-16-148; DO-TH-16-15; arXiv:1609.06255] ddc:530
We calculate the massive Wilson coefficients for the heavy flavor contributions to the non-singlet charged current deep-inelastic scattering structure functions $F_L^{W^+}(x,Q^2)-F_L^{W^-}(x,Q^2)$ and $F_2^{W^+}(x,Q^2)-F_2^{W^-}(x,Q^2)$ in the asymptotic region $Q^2 \gg m^2$ to 3-loop order in Quantum Chromodynamics (QCD) at general values of the Mellin variable $N$ and the momentum fraction $x$. Besides the heavy quark pair production, also the single heavy flavor excitation $s \rightarrow c$ contributes. [...]
OpenAccess: Download fulltextPDF Download fulltextPDF (PDFA);

Detailed record - Similar records
2017-06-13
16:14
OpenAccess [PUBDB-2017-04838] Preprint/Report
; ;
Refined Holonomic Summation Algorithms in Particle Physics
[DESY-17-087; DO-TH-17-09; arXiv:1706.03677]
 GO
An improved multi-summation approach is introduced and discussed that enables one to simultaneously handle indefinite nested sums and products in the setting of difference rings and holonomic sequences. Relevant mathematics is reviewed and the underlying advanced difference ring machinery is elaborated upon. [...]
OpenAccess: Download fulltextPDF Download fulltextPDF (PDFA);

Detailed record - Similar records
2017-06-06
13:38
OpenAccess [PUBDB-2017-04322] Report/Journal Article
;
The method of arbitrarily large moments to calculate single scale processes in quantum field theory
[DESY-17-009; DO-TH 17-01; arXiv:1701.04614] ddc:530
We device a new method to calculate a large number of Mellin moments of single scale quantities using the systems of differential and/or difference equations obtained by integration-by-parts identities between the corresponding Feynman integrals of loop corrections to physical quantities. These scalar quantities have a much simpler mathematical structure than the complete quantity. [...]
OpenAccess: Download fulltextPDF Download fulltextPDF (PDFA);

Detailed record - Similar records
2017-06-06
11:46
OpenAccess [PUBDB-2017-04277] Preprint/Report
; ; ; et al
Three Loop Massive Operator Matrix Elements and Asymptotic Wilson Coefficients with Two Different Masses
[DESY-14-019; DO-TH-15-08; arXiv:1705.07030]
 GO
Starting at 3-loop order, the massive Wilson coefficients for deep-inelastic scattering and the massive operator matrix elements describing the variable flavor number scheme receive contributions of Feynman diagrams carrying quark lines with two different masses. In the case of the charm and bottom quarks, the usual decoupling of one heavy mass at a time no longer holds, since the ratio of the respective masses, $\eta = m_c^2/m_b^2 \sim 1/10$, is not small enough. [...]
OpenAccess: Download fulltextPDF Download fulltextPDF (PDFA);

Detailed record - Similar records
2017-06-06
11:38
OpenAccess [PUBDB-2017-04273] Preprint/Report
; ; ; et al
Iterated Elliptic and Hypergeometric Integrals for Feynman Diagrams
[DESY-16-147; DO-TH-16-14; arXiv:1706.01299]
 GO
We calculate 3-loop master integrals for heavy quark correlators and the 3-loop QCD corrections to the $\rho$-parameter. They obey non-factorizing differential equations of second order with more than three singularities, which cannot be factorized in Mellin-$N$ space either. [...]
OpenAccess: Download fulltextPDF Download fulltextPDF (PDFA);

Detailed record - Similar records