Changelog

Version 10.2

• Analytic implementation of WW+1jet, WZ+1jet and ZZ+1jet amplitudes at one loop, also available through the C++ interface.
• Implementation of WW, WZ and ZZ processes at NNLO using both qt and jettiness subtractions.
• Implementation of qt subtraction for all other colour singlet processes.
• OneLoop inserted as integral provider.
• Cleanup of implemention of lepton pair + four parton amplitudes at one loop.

Version 10.1

• C++ Interface to several tree and one-loop amplitudes, see ref. ¹. With that, added amplitudes for one-loop two-jet production and diphoton+two-jet production.
• $\text{N}^3\text{LL}'+\text{NNLO}$ $q_T$ resummation for Diphoton production, see our page for this process and ref. ²
• Implementation of t-channel single-top-quark production at NNLO, see refs. ³,⁴
• New and updated HTML documentation (T. Neumann).

Version 10.0: CuTe-MCFM

For the publication of this release please see ref.⁵

• $\text{N}^3\text{LL}+\text{NNLO}$ $q_T$ resummation for the boson processes $W^\pm,Z$ and $H$ and diboson processes $\gamma\gamma, Z\gamma, ZH$ and $W^\pm H$. Other fixed-order NLO processes can easily be interfaced for $\text{N}^2\text{LL}+\text{NLO}$ precision.
• Support for histograms with custom binning.
• Streamlined compilation process into single CMake script.

Bugfix release 10.0.1

• Changed that new histograms are routines are not used by default.
• Fixed wrong sign of PDF uncertainties.
• Fixed installation of qd/qcdloop/lhapdf on some systems with default library installation path of "lib64" instead of "lib".
• Fixed selection of resummation components which caused random failures of some processes.

MCFM-10.0 implements a new plotting infrastructure that allows for much easier setup and custom-binned histograms. The new style histograms can be enabled by setting newstyle = .true. in the [histogram] section of the input file. An example for $Z$ production with resummation and custom binning is given in src/User/nplotter_Z_new.f90. Each plotter implements a new Fortran module with a function setup() that is called once at the beginning of MCFM to set up the histogram binnings. The function book(p,wt,ids,vals,wts) is called for each phase space point, calculates the observables based on the jet four-momenta in p and returns them in the vals array. The wts array is typically filled with wt for each observable, but can be modified to return a different weight to the histogramming routine. This is used in the example file to implement a transition function for the resummed and fixed-order components.

To adopt a new process to the new histograms, the file src/Mods/mod_SetupPlots.f90 can be modified. More precisely, the function setup_plots needs to import the plotting module of the process, call the setup routine for the process, and set the pbook pointer to the actual book routine of the new plotting module.

Version 9.1

• New implementation of H+2j virtual matrix elements with mass effects, see ref. ⁶.
• Upgraded QCDLoop from 2.0.2 to 2.0.5

Version 9.0: "Moving beyond Fortran77"

This release is a major code overhaul based on ref.⁷. Please see our PDF manual bundled with MCFM (in Doc/manual.pdf) for detailed information.

• Overhaul of the code and additionally offering many new features such as an efficient calculation of scale and PDF uncertainties and a robust estimate of residual slicing-dependence (for NNLO calculations).
• Consistent licensing under GPL-3.0.

Versions earlier than 9.0

Versions earlier than 9.0 can still be obtained on the MCFM homepage . The manual in Doc/ contains a brief list of changes for each release.

References

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1. John M. Campbell, Stefan Höche, and Christian T. Preuss. Accelerating LHC phenomenology with analytic one-loop amplitudes: A C++ interface to MCFM. Eur. Phys. J. C, 81$12$:1117, 2021. arXiv:2107.04472, doi:10.1140/epjc/s10052-021-09885-0. ↩

2. Tobias Neumann. The Diphoton $q\_T$ spectrum at N³LL$^\prime $+NNLO. EPJC, 7 2021. arXiv:2107.12478. ↩

3. John Campbell, Tobias Neumann, and Zack Sullivan. Single-top-quark production in the $t$-channel at NNLO. JHEP, 02:040, 2021. arXiv:2012.01574, doi:10.1007/JHEP02$2021$040. ↩

4. John Campbell, Tobias Neumann, and Zack Sullivan. Testing parton distribution functions with t-channel single-top-quark production. Phys. Rev. D, 104$9$:094042, 2021. arXiv:2109.10448, doi:10.1103/PhysRevD.104.094042. ↩

5. Thomas Becher and Tobias Neumann. Fiducial qT resummation of color-singlet processes at N³LL+NNLO. JHEP, 03:199, 2021. arXiv:2009.11437, doi:10.1007/JHEP03$2021$199. ↩

6. Lucy Budge, John M. Campbell, Giuseppe De Laurentis, R. Keith Ellis, and Satyajit Seth. The one-loop amplitudes for Higgs + 4 partons with full mass effects. JHEP, 05:079, 2020. arXiv:2002.04018, doi:10.1007/JHEP05$2020$079. ↩

7. John Campbell and Tobias Neumann. Precision Phenomenology with MCFM. JHEP, 12:034, 2019. arXiv:1909.09117, doi:10.1007/JHEP12$2019$034. ↩