Search

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., 16 pages, lots of screenshots

We develop an algorithm called SPBcal under Java SE runtime environment 1.8.0_131 to calculate transport parameters of thermoelectric materials within the framework of single parabolic band (SPB) model. For calculating Fermi–Dirac integrals, SPBcal is implemented by a double exponential transformation combined with trapezoidal rule to calculate F 1 ( η ) and F 2 ( η ) and the trapezoidal rule with pole correction to calculate F − 1 2 η and F 1 2 η , with which good accuracy of the transport parameters as a function of temperature can be obtained with very low execution time of the algorithm as long as the experimentally determined Seebeck coefficients are given. The SPBcal is tested and the results are consistent with the data reported in the literature. Program summary Program title: SPBcal v1.0 Program files doi: http://dx.doi.org/10.17632/8r5ybpjrbb.1 Licensing provisions: MIT license (MIT) Programming language: Java Nature of problem: Quickly calculating thermoelectric transport parameters for materials with single parabolic band under the assumption of acoustic phonon scattering as a main event. Solution method: Double exponential and pole correction in combination with trapezoidal rule for calculating integer and half Fermi–Dirac integrals, respectively. “For Loop” iteration for determining reduced Fermi energy. Additional comments: Program Github repository https://github.com/charliech17/SPBcal/releases

The computation of renormalized one-loop amplitudes in quantum field theory requires not only the knowledge of the Lagrangian density and the corresponding Feynman rules, but also that of the ultraviolet counterterms. More in general, and depending also on the method used in the actual computation of the one-loop amplitudes, additional interactions might be needed. One example is that of the R 2 rational terms in the OPP method. In this paper, we argue that the determination of all elements necessary for loop computations in arbitrary models can be automated starting only from information on the Lagrangian at the tree-level. In particular, we show how the R 2 rational and ultraviolet counterterms for any renormalizable model can be computed with the help of a new package, which we name NLOCT and builds upon FeynRules and FeynArts . To show the potential of our approach, we calculate all additional rules that are needed to promote a Two Higgs Doublet Model Lagrangian to one-loop computations in QCD and electroweak couplings. Program summary Program title: FeynRules-2.1 with NLOCT Catalogue identifier: AEDI_v2_1 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AEDI_v2_1.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 58179 No. of bytes in distributed program, including test data, etc.: 506216 Distribution format: tar.gz Programming language: Mathematica. Computer: Platforms on which Mathematica is available. Operating system: Operating systems on which Mathematica is available. Classification: 11.1, 11.6. Catalogue identifier of previous version: AEDI_v2_0 Journal reference of previous version: Comput. Phys. Comm. 185(2014)2250 External routines: FeynArts-3.7 or above Does the new version supersede the previous version?: Yes Nature of problem: The new version of FeynRules renormalizes and computes with the new NLOCT package the ultraviolet counterterms and the rational R 2 terms induced by one-loop amplitudes. The resulting vertices can be exported in the UFO format to event generators such as MadGraph5_aMC@NLO. Solution method: First, the Lagrangian is renormalized in FeynRules and exported to FeynArts through the corresponding interface. Secondly, the NLOCT package computes the R 2 and U V vertices using the amplitudes from FeynArts. Finally, the list of NLO vertices is loaded in FeynRules to be exported in the UFO format. Reasons for new version: The new version allows the automated generation of any model in the UFO format with all the required ingredients to perform automatically one-loop computation. Summary of revisions: This new version contains all the elements to perform the computation of the NLO ingredients: A function to perform the renormalization in FeynRules, the NLOCT package computes of the U V and R 2 vertices and the extended UFO interface adds them in the output. Restrictions: The model should be renormalizable, i.e. the dimension of the operators should not exceed four, and written in the Feynman gauge. Running time: The running time ranges from a few minutes for models like the SM to a few hours for more complicated models like the MSSM.

aITALC, a new tool for automating loop calculations in high energy physics, is described. The package creates Fortran code for two-fermion scattering processes automatically, starting from the generation and analysis of the Feynman graphs. We describe the modules of the tool, the intercommunication between them and illustrate its use with three examples., 24 pages, 5 figures, 8 tables