### Description

"Calculations for Modern and Future Colliders" satellite workshop

Konstantin Chetyrkin
(Karlsruhe Institute of Technology)

23/07/2015, 14:30

We discuss the current status of the ongoing analytical calculation of
the QCD beta-function in 5 loops as well as some new results in
investigating CBK (Crewther-Brodhurst-Kataev) relation in QCD. The
latter include the evaluation of the new singlet type contribution to
the Bjorken sum rule (first considered by Larin) which appears first
at 4-loop level only. We will also report on the...

Andrey Grozin
(urn:Google)

23/07/2015, 15:00

The three-loop cusp anomalous dimension $\Gamma$ has been calculated analytically, as a function of the Minkowski angle $\phi$,
via harmonic polylogarithms up to weight 5. The color structures
$C_F (T_F n_f)^{L-1} \alpha_s^L$ in $\Gamma$ and the HQET quark field anomalous dimension have been obtained to all orders. At
large $\phi$ the coefficient of $1/(1-z)_+$ in the DGLAP evolution kernel...

Dr
Andrei Kataev
(Institute for Nuclear Reserch of the Russian Academy of Sciences)

23/07/2015, 15:30

The current knowledge on the three-loop approximation of the static
potential in QCD is reviewed . The results are used for the determination of the
4-th order approximation of the QCD $\beta$-function and for the $e^+e^-$-annihilation R-ratio in the V-scheme. The results are compared with the ones obtained in the
$\overline{MS}$-scheme and minimal MOM scheme in the Landau gauge. The...

Mikhail Kompaniets
(St. Petersburg State University (RU))

23/07/2015, 16:20

Using R* operation, IBP and integration of hyperlogarithms (HyperInt)
we perform 6 loop calculation of beta function in $\phi^4$ model.
One of the remarkable features of this result is that 6 loop term contains multiple zeta values. We discuss different aspects of this calculations as well as series resummation and predictions for 6 loop term based on Kazakov/Shirkov/Tarasov (1979) paper

Dr
Alexander Bednyakov
(JINR)

23/07/2015, 16:50

Two-loop electroweak corrections to the decoupling relations between the running $\overline{MS}$ parameters of the SM and their counterparts in the effective five-flavour QCDxQED theory are considered for the strong coupling constant $\alpha_s(\mu)$ and the bottom-quark mass $m_b(\mu)$ . The decoupling procedure is outlined and the numerical impact of the obtained terms are discussed.

Andrey Pikelner
(BLTP JINR)

23/07/2015, 17:10

We present our progress in calculation of four-loop beta-functions in the SM. The results for the strong coupling is obtained in the gaugeless limit. Pure QCD part coincides with known expressions. The method of calculation and validation of the result are discussed.

Anton Trunin
(Joint Institute for Nuclear Research)

23/07/2015, 17:30

On the basis of perturbative QCD and relativistic quark model we calculate cross sections of pair pseudoscalar and vector $B_c$ mesons production in proton--proton interaction. Relativistic factors in the production amplitude connected with the relative motion of heavy quarks and the transformation law of the bound state wave function are taken into account. The gluon and quark propagators...

Dr
Vladimir Smirnov
(SINP MSU)

24/07/2015, 14:30

Evaluating Feynman integrals by uniformly transcendental differential equations

Roman Lee
(Budker Institute of Nuclear Physics)

24/07/2015, 15:00

Recently a remarkable observation was made concerning differential equation system for multiloop integrals. It appeared that in many cases by the proper choice of functions the differential system can be represented in the form where the dependence on regularization parameter is reduced to an overall factor $\epsilon$ in the right-hand side. Such a representation makes finding general...

Alexander Smirnov
(Moscow State University)

24/07/2015, 15:30

In modern elementary particle physics one often needs to evaluate millions of Feynman integrals. An already classical approach is to apply the so-called integration by parts relations and reduce all integrals to a smaller set, the master integrals. We present FIRE5 - a powerful program performing Feynman integral reduction.

Dr
Oleg Tarasov
(JINR)

24/07/2015, 16:20

New methods for deriving functional equations for Feynman integrals
are proposed. Several examples of functional equations for two-loop
integrals are considered in detail. Application of functional
equations for analytic continuation of Feynman integrals
considered in arbitrary space-time dimension is demonstrated.

Dmitry Vlasenko
(Southern Federal University)

24/07/2015, 16:40

The SYM theory in higher dimensions, namely D=6,8,10 cases were considered. The main interest is UV divergence of the theory, basically leading pole behavior. Based on calculation of some first loops an iterative procedure which allows to predict leading poles in each order without its direct calculation were constructed. Using this procedure a set of equations which provides a possibility to...

Dr
Andrei Davydychev
(SINP MSU and Schlumberger)

24/07/2015, 17:00

Different representations for the three-body phase space are considered, exploring their symmetry properties and geometrical meaning. We derive expressions that are explicitly symmetrical in the masses of the three particles. We study geometrical properties of the variables involved in elliptic integrals and demonstrate that it is convenient to use the Jacobian zeta function to express the...

Dr
César Ayala
(Department of Theoretical Physics and IFIC, University of Valencia and CSIC, E-46100, Valencia, Spain)

24/07/2015, 17:20

We investigate a novel non-perturbative QCD running coupling motivated by confinement and asymptotic freedom.
This coupling is formulated in terms of a gluon mass function analogous to that of Dyson-Schwinger approaches. We calculate the corresponding potential à la Richardson and are able to reproduce the Cornell potential. The resulting gluon mass is close to the Dyson-Schwinger parameter.

Victor Kim
(St. Petersburg Nuclear Physics Institute - PNPI, Gatchina)

26/07/2015, 14:30

Brief overview of searches for BFKL-evolution manifestations at high energies is presented. Data comparison with the predictions of BFKL-evolution in the leading logarithm (LL) and next-to-leading logarithm (NLL) approximations are discussed.

Vladimir Saleev
(Samara State University)

26/07/2015, 15:30

An overview of recent results (2010-2015) obtained in the Parton Reggeization Approach (PRA) are presented. The dominance of multi-Regge final states in particle production at high energies needs the kt-factorization (high-energy factorization) approach for description of hard hadron-hadron collisions instead of the collinear approximation of the conventional Parton Model. The Lipatov's...

Alexandera Shipilova
(Samara State University, Samara State Aerospace University)

26/07/2015, 16:20

We study inclusive azimuthal decorrelations in jet, b-jet and D-meson pair production in proton-proton collisions at the CERN LHC invoking the hypothesis of parton Reggeization in t-channel exchanges at high energies. Using a high-energy factorization scheme with the Kimber-Martin-Ryskin unintegrated parton distribution functions and the Fadin-Lipatov effective vertices we obtain good...

Mr
Maxim Nefedov
(Samara State University)

26/07/2015, 16:40

The hadroproduction of prompt isolated photon pairs at high energies is studied in the NLO* framework of the Parton Reggeization Approach. The real part of the NLO corrections is computed, and the procedure for the subtraction of double counting between real parton emissions in the hard-scattering matrix element and unintegrated PDF is constructed for the amplitudes with Reggeized quarks in...

Igor Cherednikov
(University of Antwerp)

26/07/2015, 17:00

We address several unresolved issues in the QCD-based description of the three-dimensional inner structure of the nucleon accessible in the current and planned high-energy experiments. The emphasis is placed on the comparison of existing perturbative resummation methods and corresponding evolution equations (DGLAP, BFKL, CCFM, SCET etc.) for transverse-momentum dependent parton distribution...

Oleg Veretin
(University of Hamburg, II. Theoretical Institute)

26/07/2015, 17:20

We study the relationships between the basic parameters of the on-shell renormalization scheme and their counterparts in the $\overline{\mathrm{MS}}$ scheme at full order $\mathcal{O}(\alpha^2)$ in the Standard Model. These enter as threshold corrections the renormalization group analyses underlying, e.g., the investigation of the vacuum stability. To ensure the gauge invariance of the...

Dr
Mikhail Dolgopolov
(Samara State University)

27/07/2015, 14:30

The development of the catastrophe theory methods is proposed
for the effective Higgs type potentials stability conditions. The role of temperature effective loop corrections
and the temperature evolution of phase transitions in some advanced two-doublet models are considered.

Mr
Sergey Volkov
(SINP MSU, Dubna)

27/07/2015, 15:00

A "forest-like" subtraction scheme is proposed for removal both ultraviolet and infrared divergences in Feynman amplitudes. This scheme is developed especially for QED calculation of the anomalous magnetic moment. The procedure gives a finite Feynman-parametric integral for any Feynman diagram (at any order of perturbation), so we don't need any regularization. The subtraction scheme is...

Luca Panizzi
(University of Southampton)

27/07/2015, 15:30

New heavy quarks are predicted in various scenarios of new
physics; depending on their nature they can mix with SM quarks or they
can even mediate the production of dark matter states.
Theoretically-motivated scenarios of new physics in general predict the
existence of multiple new quarks with different couplings with the SM
states or dark matter. Experimental searches of new quarks at...

Dr
Grigory Pivovarov
(Russian Academy of Sciences (RU))

27/07/2015, 16:20

Two existing approaches to the evolution of the scalar mass are discussed. In particular, their opposite implications for the naturalness problem are pointed out. Next, a possibility of an alternative approach to computing the renormalization group evolution of the standard model parameters is discussed. Within this approach, the naturalness problem may be moved to a high energy scale which...

Andrei Onishchenko

27/07/2015, 16:40

We will describe the methods and techniques used both to perform and automate calculations of quarkonia production at NLO accuracy. We will also present some preliminary results for the case of pair production.

Alexander Ochirov
(University of Edinburgh)

27/07/2015, 17:00

We explore implications of the color-kinematics duality for quantum chromodynamics with massive quarks. We work out a decomposition n-point tree amplitudes in a small basis of color-ordered "primitive'' amplitudes, using general properties of color and kinematics. First, we decompose the full scattering amplitude with 2k quarks and (n-2k) gluons in terms of the Melia basis, which consists of...

Dr
Anton Baushev
(Observatotio Cerro Calan, Departamento de Astronomia, Universidad de Chile, Santiago, Chile)

27/07/2015, 17:20

The question of the density profile of dark matter halos is extremely important for various topics of the dark matter physics. In principle, it can shed light on the physical nature of the dark matter. Now the contradiction between the standard dark matter paradigm and observations seems obvious. The main aim of the talk is to discuss the ways to agree theory with observations. We show that...

Ms
Gayatri Ghosh
(Physics Department, Gauhati University)

27/07/2015, 17:40

Using the results from LHC on Higgs mass, we present limits on Lepton Flavor Violation(LFV), in SUSY SO(10) theories. We have used Dirac Neutrino Yukawa Couplings as calculated in such theories. We have presented our results using different models like NUHM, mSUGRA, NUGM. We have compared our results with latest data from MEG experiment on charged lepton flavor violation. Latest results from...

Ringaile Placakyte
(Deutsches Elektronen-Synchrotron (DE))

28/07/2015, 14:30

The uncertainties of protons parton distribution functions (PDFs) play a dominant role for the precision tests of the Standard Model (SM) and they also impact substantially the theory predictions of Beyond SM high mass production. We present the HERAFitter project which provides a unique open-source software framework for the determination of the proton's PDFs and for the interpretation of...

Andrey Sapronov
(Joint Inst. for Nuclear Research (RU))

28/07/2015, 15:00

The report presents new features of the MCSANC program, a Monte
Carlo tool for calculation of the next-to-leading order electroweak and QCD
corrections to various Standard Model processes.
The extensions concern implementation of the Drell-Yan-like
processes and include systematic treatment of the photon-induced contribution in
proton-proton collisions and electroweak corrections beyond...

Thomas Luebbert
(University of Hamburg)

28/07/2015, 15:30

qT spectra of massive bosons at hadron colliders provide important tests of the Standard Model. In the crucial region, where the boson's invariant mass M is much smaller than its transverse momentum qT, the spectra are very sensitive to initial state radiation.
Applying soft-collinear effective theory, a universal framework for its description has been established and the relevant...

Mr
Nikolay Krasnikov
(INR, Moscow)

28/07/2015, 16:20

We review the phenomenology and the experiments on the search for light vector boson.
The existence of the additional light vector boson was proposed for the
explanation of the (g-2) muon anomaly.

Yahor Dydyshka
(Byelorussian State University (BY))

28/07/2015, 16:40

We present strategy for optimization of the scattering amplitude calculation using Clifford algebra. Application to the one-loop tensor integral reduction is demonstrated.

Vitaly Yermolchyk
(Byelorussian State University (BY))

28/07/2015, 17:00

We present the Monte Carlo event generator *LePaProGen* for neutral and charged current Drell-Yan processes, which is intended for accurate and fast generation of events taking in account higher-order radiative corrections. We introduce some new physical algorithms and code features like independent algorithm for the optimal selection of variables for phase-space parametrization.

Mark Sutton
(University of Sussex (GB))

28/07/2015, 17:20

Recent developments in the fast reproduction of the results of QCD calculations
using the APPLgrid project are presented. The calculation of cross-sections at
Next-to-Leading order in QCD involves the integration over the final state phase
space in order to cancel the infra-red divergences. For the calculation of cross
sections for observables at hadron-hadron colliders this...

Dr
Alexander Nesterenko
(Joint Institute for Nuclear Research)

29/07/2015, 14:30

The dispersive approach to QCD is applied to the study of the hadronic
vacuum polarization function and associated quantities. This approach
merges the intrinsically nonperturbative constraints, which originate
in the kinematic restrictions on the respective physical processes,
with corresponding perturbative input. The obtained hadronic vacuum
polarization function agrees with pertinent...

Dr
Anatoly Kotikov
(BLTP JINR)

29/07/2015, 15:30

I will review the results for master integrals having the property of
maximal transcendentality.

Dr
Sergey Larin
(INR RAS, Moscow)

29/07/2015, 16:20

The QCD Lagrangian is modified by adding gluon masses to ensure the agreement of the theory with experiments. On mass-shell renormalizability of the resulting model is demonstrated.

Dr
Vladimir Zykunov
(BelSUT)

29/07/2015, 16:40

A method for taking into account radiative events with hard photon emission in experiments
aimed at studying Moller scattering with polarized particles was developed.
A computer code used to perform a numerical analysis with allowance for the kinematical conditions
of the MOLLER experiment at the Jefferson Lab was constructed.
The respective results were compared with their counterparts...

Dr
Inna Serenkova
(Gomel State Technical University)

29/07/2015, 17:00

The prospects of discovery and identification of large
extra spatial dimensions effects in the process of lepton and
photon pair production at the Large Hadron Collider (LHC) were
studied. These effects can be found by the specific behavior of
the invariant mass distributions of the lepton and photon pairs.
Identification of the effects under study can be performed with
angular...