413 research outputs found
Momentum Dependent Two-Loop Corrections to the Neutral Higgs Boson Masses in the MSSM
The momentum dependent two-loop contributions of the order
() to the masses in the Higgs-boson sector of
the MSSM are computed. Adopting the Feynman-diagrammatic approach and using a
mixed on-shell/ renormalization scheme, the new corrections can
directly be matched onto the higher-order corrections included in the code
FeynHiggs. Two-loop diagrams involving several mass scales are evaluated with
the program SecDec. The combination of the new momentum dependent two-loop
contribution with the existing one- and two-loop corrections leads to an
improved prediction of the light MSSM Higgs-boson mass with reduced theoretical
uncertainty. The resulting shifts in the lightest Higgs-boson mass can
extend up to the level of the current experimental uncertainty of about 500 MeV
in the scenario considered in these proceedings.Comment: 8 pages, 3 figures, contribution to the proceedings of the Loops and
Legs 2014 conferenc
Numerical evaluation of two-loop integrals with pySecDec
We describe the program pySecDec, which factorises endpoint singularities
from multi-dimensional parameter integrals and can serve to calculate integrals
occurring in higher order perturbative calculations numerically. We focus on
the new features and on frequently asked questions about the usage of the
program.Comment: 11 pages, to appear in the proceedings of the HiggsTools Final
Meeting, IPPP, University of Durham, UK, September 201
SecDec-3.0: numerical evaluation of multi-scale integrals beyond one loop
SecDec is a program which can be used for the factorization of dimensionally
regulated poles from parametric integrals, in particular multi-loop integrals,
and the subsequent numerical evaluation of the finite coefficients. Here we
present version 3.0 of the program, which has major improvements compared to
version 2: it is faster, contains new decomposition strategies, an improved
user interface and various other new features which extend the range of
applicability.Comment: 46 pages, version to appear in Comput.Phys.Com
Higgs boson pair production in gluon fusion at NLO with full top-quark mass dependence
We present the calculation of the cross section and invariant mass
distribution for Higgs boson pair production in gluon fusion at next-to-leading
order (NLO) in QCD. Top-quark masses are fully taken into account throughout
the calculation. The virtual two-loop amplitude has been generated using an
extension of the program GoSam supplemented with an interface to Reduze for the
integral reduction. The occurring integrals have been calculated numerically
using the program SecDec. Our results, including the full top-quark mass
dependence for the first time, allow us to assess the validity of various
approximations proposed in the literature, which we also recalculate. We find
substantial deviations between the NLO result and the different approximations,
which emphasizes the importance of including the full top-quark mass dependence
at NLO.Comment: Version published in PRL, v2: results at 13 TeV (v1 was at 14 TeV),
minor correction to virtual part included, conclusions unchange
Loopedia, a Database for Loop Integrals
Loopedia is a new database at loopedia.org for information on Feynman
integrals, intended to provide both bibliographic information as well as
results made available by the community. Its bibliometry is complementary to
that of SPIRES or arXiv in the sense that it admits searching for integrals by
graph-theoretical objects, e.g. its topology.Comment: 16 pages, lots of screenshot
pySecDec: a toolbox for the numerical evaluation of multi-scale integrals
We present pySecDec, a new version of the program SecDec, which performs the factorization of dimensionally regulated poles in parametric integrals, and the subsequent numerical evaluation of the finite coefficients. The algebraic part of the program is now written in the form of python modules, which allow a very flexible usage. The optimization of the C++ code, generated using FORM, is improved, leading to a faster numerical convergence. The new version also creates a library of the integrand functions, such that it can be linked to user-specific codes for the evaluation of matrix elements in a way similar to analytic integral libraries
Probing the scalar potential via double Higgs boson production at hadron colliders
We present a sensitivity study on the cubic and quartic self couplings in double Higgs production via gluon fusion at hadron colliders. Considering the relevant operators in the Standard Model Effective Field Theory up to dimension eight, we calculate the dominant contributions up to two-loop level, where the first dependence on the quartic interaction appears. Our approach allows to study the independent variations of the two self couplings and to clearly identify the terms necessary to satisfy gauge invariance and to obtain UV-finite results order by order in perturbation theory. We focus on the bb¯ γγ signature for simplicity and provide the expected bounds for the cubic and quartic self couplings at the 14 TeV LHC with 3000 fb −1 (HL-LHC) and for a future 100 TeV collider (FCC-100) with 30 ab −1 . We find that while the HL-LHC will provide very limited sensitivity on the quartic self coupling, precision measurements of double Higgs production at a FCC-100 will offer the opportunity to set competitive bounds. We show that combining information from double and triple Higgs production leads to significantly improved prospects for the determination of the quartic self coupling
Factors for of the formation of the quality of professional training of a skilled worker
В статті розглянуто особливості формування якості професійної підготовки здобувачів освіти в закладах професійної (професійно-технічної) освіти в умовах реалізації Закону України «Про освіту». Розглянута важливість проектування освітнього процесу закладів професійної (професійно-технічної) освіти на основі результатів навчання, які мають оцінюватися як навчальні досягнення здобувачів освіти та формують їх професійну компетентність, що, в свою чергу, забезпечує підвищення конкурентоздатності випускників на ринку праці.The article considers the peculiarities of the formation of the quality of the professional training of applicants for education in the institutions of vocational (vocational) education in the conditions of implementation of the Law of Ukraine "On Education". Considered the importance of designing the educational process of professional (vocational) education institutions based on learning outcomes, which should be evaluated as educational achievements of the education providers and form their professional competence, which, in turn, ensures higher competitiveness of graduates in the labor market
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