SUSY Les Houches Accord 2

The Supersymmetry Les Houches Accord (SLHA) provides a universal set of conventions for conveying spectral and decay information for supersymmetry analysis problems in high energy physics. Here, we propose extensions of the conventions of the first SLHA to include various generalisations: the minimal supersymmetric standard model with violation of CP, R-parity, and flavour, as well as the simplest next-to-minimal model.     

A standard format for Les Houches Event Files

A standard file format is proposed to store process and event information, primarily output from parton-level event generators for further use by general-purpose ones. The information content is identical with what was already defined by the Les Houches Accord five years ago, but then in terms of Fortran commonblocks. This information is embedded in a minimal XML-style structure, for clarity and to simplify parsing.     

A proposal for a standard interface between Monte Carlo tools and one-loop programs

Many highly developed Monte Carlo tools for the evaluation of cross sections based on tree matrix elements exist and are used by experimental collaborations in high energy physics. As the evaluation of one-loop matrix elements has recently been undergoing enormous progress, the combination of one-loop matrix elements with existing Monte Carlo tools is on the horizon. This would lead to phenomenological predictions at the next-to-leading order level. This note summarises the discussion of the next-to-leading order multi-leg (NLM) working group on this issue which has been taking place during the workshop on Physics at TeV Colliders at Les Houches, France, in June 2009. The result is a proposal for a standard interface between Monte Carlo tools and one-loop matrix element programs.Dedicated to the memory of, and in tribute to, Thomas Binoth, who led the effort to develop this proposal for Les Houches 2009. Thomas led the discussions, set up the subgroups, collected the contributions, and wrote and edited this paper. He made a promise that the paper would be on the arXiv the first week of January, and we are faithfully fulfilling his promise. In his honour, we would like to call this the Binoth Les Houches Accord.     

Fittino, a program for determining MSSM parameters from collider observables using an iterative method

Provided that Supersymmetry (SUSY) is realized, the Large Hadron Collider (LHC) and the future International Linear Collider (ILC) may provide a wealth of precise data from SUSY processes. An important task will be to extract the Lagrangian parameters. On this basis the goal is to uncover the underlying symmetry breaking mechanism from the measured observables. In order to determine the SUSY parameters, the program Fittino has been developed. It uses an iterative fitting technique and a Simulated Annealing algorithm to determine the SUSY parameters directly from the observables without any a priori knowledge of the parameters, using all available loop-corrections to masses and couplings. Simulated Annealing is implemented as a stable and efficient method for finding the optimal parameter values. The theoretical predictions can be provided from any program with SUSY Les Houches Accord interface. As fit result, a set of parameters including the full error matrix and two-dimensional uncertainty contours are obtained. Pull distributions can automatically be created and allow an independent cross-check of the fit results and possible systematic shifts in the parameter determination. A determination of the importance of the individual observables for the measurement of each parameter can be performed after the fit. A flexible user interface is implemented, allowing a wide range of different types of observables and a wide range of parameters to be used.

Program summary

Program title: FittinoCatalogue identifier: ADWNProgram summary URL:http://cpc.cs.qub.ac.uk/summaries/ADWNLicensing provisions: GNU General Public LicenseProgramming language:C++Computer: any computerOperating system: Linux and other Unix flavorsRAM: ca. 22 MBNo. of lines in distributed program, including test data, etc.: 111 962No. of bytes in distributed program, including test data, etc.: 1 006 727Distribution format: tar.gzNumber of processors used: 1External routines: The ROOT data analysis framework, the SPheno spectrum calculator (included in the distribution). (SPheno may be replaced by any SUSY code which makes predictions for observables and communicates via the SLHA.)Nature of problem: Provided supersymmetry is realized in Nature, a wealth of data will become available at the Large Hadron Collider (LHC) and the International Linear Collider (ILC). One of the most important tasks will be to extract the SUSY Lagrangian parameters from the measured observables. The large number of SUSY parameters and complicated correlations induced by loop corrections make the parameter determination difficult. Starting a global SUSY parameter fit initialized with tree-level estimates turned out to be an insufficient approach because the MINUIT fitting algorithm is likely to get stuck in local minima.Solution method: To overcome the encountered problems without using a priori knowledge, two strategies have been implemented in Fittino. The first one performs the fit in several steps (sub-sector fit method). It starts fitting certain sub-sets of parameters to certain sub-sets of observables and thereby slowly improves the parameter values. Finally the values are good enough to start a global SUSY parameter fit.The second approach uses simulated annealing to improve the tree-level estimates of the parameters to an extend where MINUIT succeeds to perform a global SUSY parameter fit.Restrictions: The current version of Fittino (version 1.1.1) assumes that there is no CP violation in the SUSY sector, no mixing between generations and no mixing within the first two generations.Running time: Depending on the complexity of the problem, the running time varies from a few minutes to several weeks.     

SuperLFV: An SLHA tool for lepton flavor violating observables in supersymmetric models

We introduce SuperLFV, a numerical tool for calculating low-energy observables that exhibit charged lepton flavor violation (LFV) in the context of the minimal supersymmetric standard model (MSSM). As the Large Hadron Collider and MEG, a dedicated μ⁺→e⁺γ${\mu }^{+}\to e^{+}\gamma$ experiment, are presently acquiring data, there is need for tools that provide rapid discrimination of models that exhibit LFV. SuperLFV accepts a spectrum file compliant with the SUSY Les Houches Accord (SLHA), containing the MSSM couplings and masses with complex phases at the supersymmetry breaking scale. In this manner, SuperLFV is compatible with but divorced from existing SLHA spectrum calculators that provide the low energy spectrum. Hence, input spectra are not confined to the LFV sources provided by established SLHA spectrum calculators. Input spectra may be generated by personal code or by hand, allowing for arbitrary models not supported by existing spectrum calculators.     

SUSY Les Houches Accord 2 I/O made easy

A library for reading and writing data in the SUSY Les Houches Accord 2 format is presented. The implementation is in native Fortran 77. The data are contained in a single array conveniently indexed by preprocessor statements.

Program summary

Program title: SLHA2LibCatalogue identifier: AEDY_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEDY_v1_0.htmlProgram obtainable from: CPC Program Library, Queen's University, Belfast, N. IrelandLicensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.htmlNo. of lines in distributed program, including test data, etc.: 7550No. of bytes in distributed program, including test data, etc.: 160 123Distribution format: tar.gzProgramming language: FortranComputer: For the build process, a Fortran 77 compiler in a Unixish environment (make, shell) are requiredOperating system: Linux, Mac OS, Windows (Cygwin), Tru64 UnixRAM: The SLHA Record is currently 88 944 bytes longClassification: 4.14, 11.6Nature of problem: Exchange of SUSY parameters and decay information in an ASCII file format.Solution method: The SLHA2Lib provides routines for reading and writing files in the SUSY Les Houches Accord 2 format, a common interchange format for SUSY parameters and decay data.Restrictions: The fixed-sized array that holds the SLHA2 data necessarily limits the amount of decay data that can be stored. This limit can be enlarged by editing and re-running the SLHA2.m program.Unusual features: Data are transported in a single “double complex” array in Fortran, indexed through preprocessor macros. This is about the simplest conceivable container and needs neither dynamic memory allocation nor Fortran extension like structures.Running time: Both reading and writing a SLHA file are typically in the range of a few milliseconds.     

SuperIso v2.3: A program for calculating flavor physics observables in supersymmetry

We describe SuperIso v2.3 which is a public program for evaluation of flavor physics observables in the minimal supersymmetric extension of the Standard Model (MSSM). SuperIso v2.3, in addition to the isospin asymmetry of B→K^∗γ, which was the main purpose of the first version, incorporates new flavor observables such as the branching ratio of Bs→μ⁺μ⁻, the branching ratio of B→τντ, the branching ratio of B→Dτντ and the branching ratio of K→μνμ. The calculation of the branching ratio of B→Xsγ is also improved in this version, as it now includes NNLO Standard Model contributions in addition to partial NLO supersymmetric contributions. The program also computes the muon anomalous magnetic moment (g−2). Four sample models are included in the package, namely mSUGRA, NUHM, AMSB and GMSB. SuperIso uses a SUSY Les Houches Accord file (SLHA1 or SLHA2) as input, which can be either generated automatically by the program via a call to external spectrum calculators, or provided by the user. The calculation of the observables is detailed in the Appendices, where a suggestion for the allowed intervals for each observable is also provided.

Program summary

Program title: SuperIsoCatalogue identifier: AEAN_v2_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEAN_v2_0.htmlProgram obtainable from: CPC Program Library, Queen's University, Belfast, N. IrelandLicensing provisions: GNU General Public LicenceNo. of lines in distributed program, including test data, etc.: 5977No. of bytes in distributed program, including test data, etc.: 39 375Distribution format: tar.gzProgramming language: C (C99 Standard compliant)Computer: 32- or 64-bit PC, MacOperating system: Linux, MacOSRAM: less than 1 MbClassification: 11.6Catalogue identifier of previous version: AEAN_v1_0Journal reference of previous version: Comput. Phys. Comm. 178 (2008) 745External routines: ISASUGRA/ISAJET and/or SOFTSUSYDoes the new version supersede the previous version?: yesNature of problem: Calculation of flavor physics observables as well as the muon anomalous magnetic moment in the Minimal Supersymmetric Standard Model with minimal flavor violation, in order to derive constraints on the supersymmetric parameter space.Solution method: SuperIso uses a SUSY Les Houches Accord file, which can be either generated automatically via a call to SOFTSUSY or ISAJET, or provided by the user. This file contains the masses and couplings of the supersymmetric particles. SuperIso then computes the most constraining flavor physics observables and the muon (g−2). SuperIso is able to perform the calculations in different supersymmetry breaking scenarios, such as mSUGRA, NUHM, AMSB and GMSB.Reasons for new version: This new version incorporates the calculation of several additional observables, and the inclusive branching ratio of b→sγ is now computed at NNLO accuracy for the Standard Model. The implemented routines are therefore extensively modified.Summary of revisions:

•

Compatibility with the SLHA2 input file format

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Implementation of the calculation of the muon anomalous magnetic moment

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Implementation of observables related to leptonic and semi-leptonic B meson decays

•

Implementation of observables related to K meson decays

•

Improvement of the calculations of the branching ratio of b→sγ (now at NNLO accuracy) and the isospin asymmetry of B→K∗γ

•

Update of parameters to their latest values

Unusual features: The code is very modular, and new routines for calculating new observables can be easily added.Running time: less than 1 sec     

HFOLD - A program package for calculating two-body MSSM Higgs decays at full one-loop level

HFOLD (Higgs Full One Loop Decays) is a Fortran program package for calculating all MSSM Higgs two-body decay widths and the corresponding branching ratios at full one-loop level. The package is done in the SUSY Parameter Analysis convention and supports the SUSY Les Houches Accord input and output format.

Program summary

Program title: HFOLDCatalogue identifier: AEJG_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEJG_v1_0.htmlProgram obtainable from: CPC Program Library, Queen?s University, Belfast, N. IrelandLicensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.htmlNo. of lines in distributed program, including test data, etc.: 340 621No. of bytes in distributed program, including test data, etc.: 1 760 051Distribution format: tar.gzProgramming language: Fortran 77Computer: Workstation, PCOperating system: LinuxRAM: 524 288 000 BytesClassification: 11.1External routines: LoopTools 2.2 (http://www.feynarts.de/looptools/), SLHALib 2.2 (http://www.feynarts.de/slha/). The LoopTools code is included in the distribution package.Nature of problem: A future high-energy e⁺e⁻ linear collider will be the best environment for the precise measurements of masses, cross sections, branching ratios, etc. Experimental accuracies are expected at the per-cent down to the per-mile level. These must be matched from the theoretical side. Therefore higher order calculations are mandatory.Solution method: This program package calculates all MSSM Higgs two-body decay widths and the corresponding branching ratios at full one-loop level. The renormalization is done in the DR scheme following the SUSY Parameter Analysis convention. The program supports the SUSY Les Houches Accord input and output format.Running time: The example provided takes only a few seconds to run.     

SLHAplus: A library for implementing extensions of the standard model

We provide a library to facilitate the implementation of new models in codes such as matrix element and event generators or codes for computing dark matter observables. The library contains an SLHA reader routine as well as diagonalisation routines. This library is available in CalcHEP and micrOMEGAs. The implementation of models based on this library is supported by LanHEP and FeynRules.

Program summary

Program title: SLHAplus_1.3Catalogue identifier: AEHX_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEHX_v1_0.htmlProgram obtainable from: CPC Program Library, Queen's University, Belfast, N. IrelandLicensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.htmlNo. of lines in distributed program, including test data, etc.: 6283No. of bytes in distributed program, including test data, etc.: 52 119Distribution format: tar.gzProgramming language: CComputer: IBM PC, MACOperating system: UNIX (Linux, Darwin, Cygwin)RAM: 2000 MBClassification: 11.1Nature of problem: Implementation of extensions of the standard model in matrix element and event generators and codes for dark matter observables.Solution method: For generic extensions of the standard model we provide routines for reading files that adopt the standard format of the SUSY Les Houches Accord (SLHA) file. The procedure has been generalized to take into account an arbitrary number of blocks so that the reader can be used in generic models including non-supersymmetric ones. The library also contains routines to diagonalize real and complex mass matrices with either unitary or bi-unitary transformations as well as routines for evaluating the running strong coupling constant, running quark masses and effective quark masses.Running time: 0.001 sec     

Vbfnlo: A parton level Monte Carlo for processes with electroweak bosons

Vbfnlo is a fully flexible parton level Monte Carlo program for the simulation of vector boson fusion, double and triple vector boson production in hadronic collisions at next-to-leading order in the strong coupling constant. Vbfnlo includes Higgs and vector boson decays with full spin correlations and all off-shell effects. In addition, Vbfnlo implements CP-even and CP-odd Higgs boson via gluon fusion, associated with two jets, at the leading-order one-loop level with the full top- and bottom-quark mass dependence in a generic two-Higgs-doublet model.A variety of effects arising from beyond the Standard Model physics are implemented for selected processes. This includes anomalous couplings of Higgs and vector bosons and a Warped Higgsless extra dimension model. The program offers the possibility to generate Les Houches Accord event files for all processes available at leading order.

Program summary

Program title:VbfnloCatalogue identifier: AEDO_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEDO_v1_0.htmlProgram obtainable from: CPC Program Library, Queen's University, Belfast, N. IrelandLicensing provisions: GPL version 2No. of lines in distributed program, including test data, etc.: 339 218No. of bytes in distributed program, including test data, etc.: 2 620 847Distribution format: tar.gzProgramming language: Fortran, parts in C++Computer: AllOperating system: Linux, should also work on other systemsClassification: 11.1, 11.2External routines: Optionally Les Houches Accord PDF Interface library and the GNU Scientific libraryNature of problem: To resolve the large scale dependence inherent in leading order calculations and to quantify the cross section error induced by uncertainties in the determination of parton distribution functions, it is necessary to include NLO corrections. Moreover, whenever stringent cuts are required on decay products and/or identified jets the question arises whether the scale dependence and a k-factor, defined as the ratio of NLO to LO cross section, determined for the inclusive production cross sections are valid for the search region one is interested in.Solution method: The problem is best addressed by implementing the one-loop QCD corrections in a fully flexible NLO parton-level Monte Carlo program, where arbitrary cuts can be specified as well as various scale choices. In addition, any currently available parton distribution function set can be used through the LHAPDF library.Running time: Depending on the process studied. Usually from minutes to hours.     

SuperIso v3.0, flavor physics observables calculations: extension to NMSSM

SuperIso v3.0 is a public program for evaluation of flavor physics observables in the minimal supersymmetric extension of the Standard Model (MSSM) and the next to minimal supersymmetric extension of the Standard Model (NMSSM). SuperIso v3.0 incorporates many flavor observables such as the inclusive branching ratio of B→Xsγ, the isospin asymmetry of B→K^∗γ, the branching ratio of Bs→μ⁺μ⁻, the branching ratio of B→τντ, the branching ratio of B→Dτντ, the branching ratio of K→μνμ and the branching ratios of Ds→τντ and Ds→μνμ. The calculation of the branching ratio of B→Xsγ includes NNLO Standard Model contributions. The program also computes the muon anomalous magnetic moment (g−2). Seven sample models are included in the package, namely mSUGRA, NUHM, AMSB and GMSB for the MSSM, and CNMSSM, NGMSB and NNUHM for the NMSSM. SuperIso uses a SUSY Les Houches Accord file (SLHA1 or SLHA2) as input, which can be either generated automatically by the program via a call to external spectrum calculators (SOFTSUSY, ISAJET or NMSSMTools), or provided by the user.

New version program summary

Program title:SuperIso v3.0Catalogue identifier: AEAN_v3_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEAN_v3_0.htmlProgram obtainable from: CPC Program Library, Queen's University, Belfast, N. IrelandLicensing provisions: GNU General Public LicenceNo. of lines in distributed program, including test data, etc.: 6869No. of bytes in distributed program, including test data, etc.: 42 627Distribution format: tar.gzProgramming language: C (C99 Standard compliant)Computer: 32- or 64-bit PC, MacOperating system: Linux, MacOSRAM: less than 1 MBClassification: 11.6External routines: ISASUGRA/ISAJET, SOFTSUSY and/or NMSSMToolsDoes the new version supersede the previous version?: YesNature of problem: Calculation of flavor physics observables as well as the muon anomalous magnetic moment in the Minimal Supersymmetric Standard Model with minimal flavor violation and in the Next to Minimal Supersymmetric Standard Model, in order to derive constraints on the supersymmetric parameter spaces.Solution method:SuperIso uses a SUSY Les Houches Accord (SLHA1 or SLHA2) file, which can be either generated automatically via a call to SOFTSUSY, ISAJET or NMSSMTools, or provided by the user. This file contains the masses, mixings and couplings of the supersymmetric particles. SuperIso then computes the most constraining flavor physics observables and the muon (g−2). SuperIso is able to perform the calculations in different supersymmetry breaking scenarios, such as mSUGRA, NUHM, AMSB and GMSB, as well as constrained NMSSM scenarios such as CNMSSM, NNUHM and NGMSB.Reasons for new version:SuperIso has been extended to the next to minimal supersymmetric extension of the Standard Model (NMSSM). The implemented routines are therefore extensively modified.Summary of revisions:

•

Improvement of the SLHA2 reader.

•

Replacement of “float” variables by “double”.

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Implementation of an interface with NMSSMTools.

•

Extension of the calculation of flavor observables as well as the muon anomalous magnetic moment to NMSSM.

•

Addition of three different NMSSM scenarios: CNMSSM, NGMSB and NNUHM.

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Three sample main programs have been added: cnmssm.c, ngmsb.c and nnuhm.c. Additional instructions to use them are given when running them without arguments.

Unusual features: The code is very flexible, and new observables can be added easily.Running time: Less than 1 sec     

PHANTOM: A Monte Carlo event generator for six parton final states at high energy colliders

PHANTOM is a tree level Monte Carlo for six parton final states at proton-proton, proton-antiproton and electron-positron colliders at and including possible interferences between the two sets of diagrams. This comprehends all purely electroweak contributions as well as all contributions with one virtual or two external gluons. It can generate unweighted events for any set of processes and it is interfaced to parton shower and hadronization packages via the latest Les Houches Accord protocol. It can be used to analyze the physics of boson-boson scattering, Higgs boson production in boson-boson fusion, and three boson production.

Program summary

Program title:PHANTOM (V. 1.0)Catalogue identifier: AECE_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AECE_v1_0.htmlProgram obtainable from: CPC Program Library, Queen's University, Belfast, N. IrelandLicensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.htmlNo. of lines in distributed program, including test data, etc.: 175 787No. of bytes in distributed program, including test data, etc.: 965 898Distribution format: tar.gzProgramming language: Fortran 77Computer: Any with a UNIX, LINUX compatible Fortran compilerOperating system: UNIX, LINUXRAM: 500 MBClassification: 11.1External routines: LHAPDF (Les Houches Accord PDF Interface, http://projects.hepforge.org/lhapdf/), CIRCE (beamstrahlung for e⁺e⁻ ILC collider).Nature of problem: Six fermion final state processes have become important with the increase of collider energies and are essential for the study of top, Higgs and electroweak symmetry breaking physics at high energy colliders. Since thousands of Feynman diagrams contribute in a single process and events corresponding to hundreds of different final states need to be generated, a fast and stable calculation is needed.Solution method:PHANTOM is a tree level Monte Carlo for six parton final states at proton-proton, proton-antiproton and electron-positron colliders. It computes all amplitudes at and including possible interferences between the two sets of diagrams. The matrix elements are computed with the helicity formalism implemented in the program PHACT [1]. The integration makes use of an iterative-adaptive multichannel method which, relying on adaptivity, allows the use of only a few channels per process. Unweighted event generation can be performed for any set of processes and it is interfaced to parton shower and hadronization packages via the latest Les Houches Accord protocol.Restrictions: All Feynman diagrams are computed al LO.Unusual features: Phantom is written in Fortran 77 but it makes use of structures. The g77 compiler cannot compile it as it does not recognize the structures. The Intel, Portland Group, True64 HP Fortran 77 or Fortran 90 compilers have been tested and can be used.Running time: A few hours for a cross section integration of one process at per mille accuracy. One hour for one thousand unweighted events.References:

[1]

A. Ballestrero, E. Maina, Phys. Lett. B 350 (1995) 225, hep-ph/9403244; A. Ballestrero, PHACT 1.0, Program for helicity amplitudes Calculations with Tau matrices, hep-ph/9911318, in: B.B. Levchenko, V.I. Savrin (Eds.), Proceedings of the 14th International Workshop on High Energy Physics and Quantum Field Theory (QFTHEP 99), SINP MSU, Moscow, p. 303.

     

SuperIso Relic: A program for calculating relic density and flavor physics observables in Supersymmetry

We describe SuperIso Relic, a public program for evaluation of relic density and flavor physics observables in the minimal supersymmetric extension of the Standard Model (MSSM). SuperIso Relic is an extension of the SuperIso program which adds to the flavor observables of SuperIso the computation of all possible annihilation and coannihilation processes of the LSP which are required for the relic density calculation. All amplitudes have been generated at the tree level with FeynArts/FormCalc, and widths of the Higgs bosons are computed with FeynHiggs at the two-loop level. SuperIso Relic also provides the possibility to modify the assumptions of the cosmological model, and to study their consequences on the relic density.

Program summary

Program title: SuperIso RelicCatalogue identifier: AEGD_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEGD_v1_0.htmlProgram obtainable from: CPC Program Library, Queen's University, Belfast, N. IrelandLicensing provisions: yesNo. of lines in distributed program, including test data, etc.: 2 274 720No. of bytes in distributed program, including test data, etc.: 6 735 649Distribution format: tar.gzProgramming language: C (C99 Standard compliant) and FortranComputer: 32- or 64-bit PC, MacOperating system: Linux, MacOSRAM: 100 MbClassification: 1.9, 11.6External routines: ISASUGRA/ISAJET and/or SOFTSUSY, FeynHiggsDoes the new version supersede the previous version?: No (AEAN_v2_0)Nature of problem: Calculation of the lightest supersymmetric particle relic density, as well as flavor physics observables, in order to derive constraints on the supersymmetric parameter space.Solution method: SuperIso Relic uses a SUSY Les Houches Accord file, which can be either generated automatically via a call to SOFTSUSY or ISAJET, or provided by the user. This file contains the masses and couplings of the supersymmetric particles. SuperIso Relic then computes the lightest supersymmetric particle relic density as well as the most constraining flavor physics observables. To do so, it calculates first the widths of the Higgs bosons with FeynHiggs, and then it evaluates the squared amplitudes of the diagrams needed for the relic density calculation. These thousands of diagrams have been previously generated with the FeynArts/FormCalc package. SuperIso Relic is able to perform the calculations in different supersymmetry breaking scenarios, such as mSUGRA, NUHM, AMSB and GMSB.Reasons for new version: This version incorporates the calculation of the relic density, which is often used to constrain Supersymmetry.Summary of revisions:

•

Addition of the relic density calculation

•

Replacement of "float" type by "double".

Unusual features: SuperIso Relic includes the possibility of altering the underlying cosmological model and testing the influence of the cosmological assumptions.Additional comments: This program is closely associated with the "SuperIso" program - CPC Program Library, Catalogue Id. AEAN.Running time:Compilation time: a couple of hours for the statically linked version, a few minutes for the dynamically linked version. Running time: about 1 second, or a few seconds if libraries need to be compiled on the fly.     

Stronger uncertainty relations with improvable upper and lower bounds

The quantum superposition principle is used to establish improved upper and lower bounds for the Maccone–Pati uncertainty inequality, which is based on a “weighted-like” sum of the variances of observables. Our bounds include free parameters that not only guarantee nontrivial bounds but also effectively control the bounds’ tightness. Significantly, these free parameters depend on neither the state nor the observables. A feature of our method is that any nontrivial bound can always be improved. In addition, we generalize both bounds to uncertainty relations with multiple (three or more) observables, maintaining the uncertainty relations’ tightness. Examples are given to illustrate our improved bounds.     

Ntuples for NLO events at hadron colliders

We present an event-file format for the dissemination of next-to-leading-order (NLO) predictions for QCD processes at hadron colliders. The files contain all information required to compute generic jet-based infrared-safe observables at fixed order (without showering or hadronization), and to recompute observables with different factorization and renormalization scales. The files also make it possible to evaluate cross sections and distributions with different parton distribution functions. This in turn makes it possible to estimate uncertainties in NLO predictions of a wide variety of observables without recomputing the short-distance matrix elements. The event files allow a user to choose among a wide range of commonly-used jet algorithms and jet-size parameters.     

Helac-Phegas: A generator for all parton level processes

The updated version of the Helac-Phegas¹ event generator is presented. The matrix elements are calculated through Dyson-Schwinger recursive equations using color connection representation. Phase-space generation is based on a multichannel approach, including optimization. Helac-Phegas generates parton level events with all necessary information, in the most recent Les Houches Accord format, for the study of any process within the Standard Model in hadron and lepton colliders.

New version program summary

Program title: HELAC-PHEGASCatalogue identifier: ADMS_v2_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADMS_v2_0.htmlProgram obtainable from: CPC Program Library, Queen's University, Belfast, N. IrelandLicensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.htmlNo. of lines in distributed program, including test data, etc.: 35 986No. of bytes in distributed program, including test data, etc.: 380 214Distribution format: tar.gzProgramming language: FortranComputer: AllOperating system: LinuxClassification: 11.1, 11.2External routines: Optionally Les Houches Accord (LHA) PDF Interface library (http://projects.hepforge.org/lhapdf/)Catalogue identifier of previous version: ADMS_v1_0Journal reference of previous version: Comput. Phys. Comm. 132 (2000) 306Does the new version supersede the previous version?: Yes, partlyNature of problem: One of the most striking features of final states in current and future colliders is the large number of events with several jets. Being able to predict their features is essential. To achieve this, the calculations need to describe as accurately as possible the full matrix elements for the underlying hard processes. Even at leading order, perturbation theory based on Feynman graphs runs into computational problems, since the number of graphs contributing to the amplitude grows as n!.Solution method: Recursive algorithms based on Dyson-Schwinger equations have been developed recently in order to overcome the computational obstacles. The calculation of the amplitude, using Dyson-Schwinger recursive equations, results in a computational cost growing asymptotically as 3n, where n is the number of particles involved in the process. Off-shell subamplitudes are introduced, for which a recursion relation has been obtained allowing to express an n-particle amplitude in terms of subamplitudes, with 1-, 2-, …  up to (n−1) particles. The color connection representation is used in order to treat amplitudes involving colored particles. In the present version HELAC-PHEGAS can be used to efficiently obtain helicity amplitudes, total cross sections, parton-level event samples in LHA format, for arbitrary multiparticle processes in the Standard Model in leptonic, and pp collisions.Reasons for new version: Substantial improvements, major functionality upgrade.Summary of revisions: Color connection representation, efficient integration over PDF via the PARNI algorithm, interface to LHAPDF, parton level events generated in the most recent LHA format, k_⊥ reweighting for Parton Shower matching, numerical predictions for amplitudes for arbitrary processes for phase-space points provided by the user, new user interface and the possibility to run over computer clusters.Running time: Depending on the process studied. Usually from seconds to hours.References:

[1]

A. Kanaki, C.G. Papadopoulos, Comput. Phys. Comm. 132 (2000) 306.

[2]

C.G. Papadopoulos, Comput. Phys. Comm. 137 (2001) 247.

     

On using CAD models to compute the pose of curved 3D objects

A new approach is presented for explicitly relating image observables to models of curved three-dimensional objects. This relationship is used for object recognition and positioning. Object models consist of collections of parametric surface patches. The image observables considered are raw range data, surface normal and Gaussian curvature, raw image intensity and intensity gradient, raw image contours, and contour orientation and curvature. Elimination theory provides a method for constructing an implicit equation that relates these observables to the three-dimensional position and orientation of object models. Determining the unknown pose parameters is reduced to a fitting problem between the implicit equation and the observed data points. By considering translation-independent observables such as surface normal and curvature, this process is further decomposed into first determining orientation and then determining translation. Applications to object recognition are described, and an implementation is presented.