LHC Higgs Cross Section Working Group 2 - Higgs Properties

Organization

• Group meetings: WG2: Higgs Properties
• Mailing list: lhc-higgs-properties@cernNOSPAMPLEASE.ch
• gitlab area : link
• Conveners: Sarah Heim (ATLAS - DESY 2023-), Giacomo Ortona (CMS - Torino 2023-), Daniele Barducci (Theory - University and INFN Pisa 2022-), Pier Paolo Giardino (Theory - UAM and IFT Madrid 2024-)
• Previous conveners: Ken Mimasu (Theory - University of Southampton 2021-2024), Nicolas Berger (ATLAS - Annecy LAPP 2021-2022), Mauro Donega (CMS - ETH Zurich 2021-2022), Giuliano Panico (Theory - Firenze), Jorge de Blas (Theory - Granada), Predrag Milenovic (CMS - Belgrade), Marco Delmastro (ATLAS - Annecy), Francesco Riva (Theory - CERN), David Marzocca (Theory - Trieste), Mingshui Chen (CMS - Bejing), Chris Hays (ATLAS - Oxford), Adam Falkowski (Theory - Orsay-LPT), Gino Isidori (Theory - Zürich), Michael Dührssen (ATLAS - CERN), Andre David (CMS - CERN)

Topics

• STXS & fiducial/differential XS
  • Recommendations for the fiducial and differential (Fid/DiffXS twiki) and simplified template cross sections (STXS) measurement and uncertainties computation.
  • Dedicated Fid./Diff./STXS twiki (with more details and contact emails).

• EFT
  • Tools: Implementation of Warsaw basis in FeynRules (available) with NLO QCD corrections in Madgraph (in development)
  • Validity (for discussion): defining the region of ci vs Lambda; square term gives an estimate of the uncertainty from higher powers of 1/Lambda
  • STXS->EFT mapping (available for HEL with SILH basis, in development for SMEFT with Warsaw)
  • Standard procedure for combined fit to Higgs+EW+Top data (for discussion, in coordination with other LHC Physics groups)
  • Initiative on establishing the EFT interpretation workflow guidelines/recommendations. A non-exhaustive list of aspects for discussion/clarification can be found here, together with google doc where anyone interested can sign-up for particular topics.

• CP-violation in Higgs interactions gdoc:
  • STXS bins for CPV
  • ttH phenomenological studies
  • Common parametrisations
  • CPV Benchmarks

• PO
  • Overview of effective POs and tools for extraction from measurements
  • Reweighting code to apply to existing MC
  • HiggsPO model available in Madgraph with NLO QCD corrections for VH/VBF production

Ideas for New Projects

Here we collect ideas for new topics. If you have any or find any of listed topics interesting and would like to be involved or kept in the loop, please add your name and email address in the gdoc below. It is not a commitment to definitely do anything but to be involved in further discussion and planning for the sub-activity.

• STXS
  • Stage 1.3
• CPV
  • Quantifying interplay with EDMs/low energy
  • Beyond SM Higgs joint WG3 activities

On-going projects

Topic	ShortDescription	Deliverables	Timescale	Notes	Status	Contact
STXS, CPV	CPV in STXS	tbd	2023	-	Starting/discussions
CPV	CPV in ttH	tbd	2023	-	Starting/discussions
CPV	CPV benchmarks	Note + code?	2023	-	In Progress
EFT	EFT for H+HH	Note + code?	2023	Together with HH	Starting/discussions	Ramona Gröber
STXS & differential XS, EFT	STXS EFT parametrization	Note + code?	2023	Together with LHCEFTWG	In Progress	Ken Mimasu
STXS & differential XS	STXS stage 1.2 and TH uncertainties treatment recommendation	Note/journal (+ Rivet code?)	2023	-	In Progress	Frank Tackmann
STXS & differential XS	STXS decay-side binning definition	Note + Rivet code	2022	Draft note	In progress	Michael Dührssen-Debling
EFT	Interpretation Workflow Summary: Processes, Operators and BSM Interpretations	Note	2020-2021	Addendum to BSM Benchmarks note	Stalled	Jorge de Blas
EFT	High-Energy Higgs Probes: Longitudinal multiboson processes as tests of Higgs physics	Note	2021		Stalled	Francesco Riva David Marzocca

Completed projects

Topic	ShortDescription	Deliverables	Timescale	Notes	Status	Contact
STXS & differential XS	k_lambda Note: Modelling of the single-Higgs simplified template cross-sections (STXS 1.2) for the determination of the Higgs boson trilinear self-coupling	Note	2022	LHCHWG-2022-002	Completed	WG2
STXS & differential XS	STXS stage 1.2 binning recommendation	Note/arXiv/(journal) + Rivet code	2019	Binning - missing Note	Completed	Frank Tackmann
EFT	BSM Benchmarks and mapping to EFT. Determine benchmarks sensitive to differential and coupling measurements, define relevant EFT parameters	Note/arXiv	Early 2019	arXiv LHCHXSWG-2019-006	Completed	Francesco Riva David Marzocca
EFT	Fit to STXS using a standardized mapping of STXS stage 1.2	Note/(arXiv)	Summer 2019	LHCHXSWG-2019-004	Completed	Chris Hays

Meetings (before 2021)

• WG2 fid/diff/STXS meeting: ggH stage 1.2 uncertainties 04/11/2020
• Higgs measurements and their EFT interpretations 01/7/2020
• [STXS] Meeting on Updates to Uncertainties for Stage 1.2 25/06/2020
• EXP+TH LO/NLO EFT scheme discussion: 09/04/2020
• WG2-related plenary & discussion sessions in Oct 2019 general meeting 16/10/19
• STXS gg->H & ttH closure + diffXS variables discussion 16/9/19
• STXS discussion on ttH & ggH binning (for stage 1.2) 24/7/19
• STXS discussion at Les Houches 2019 12/6/19
• ttH STXS binning discussion 6/6/2019
• Joint VBF & fid/dif/STXS meeting: STXS qq→Hqq binning 17/1/19
• WG2 session in Dec 2018 general meeting 10/12/18
• WG2 fid/dif/STXS meeting: Presentation of results and STXS updates November 23
• CP and dimension-8 EFT November 13
• Validation and benchmarking of EFT tools June 14
• STXS meeting May 17
• WG2 session in March 2018 general meeting March 27
• Benchmark scenarios February 23 (2018)
• Winter meeting December 11 (2017)
• WG2 session in July 2017 general meeting July 14
• Joint EW+WG2 meeting July 10
• STXS meeting July 6
• Kickoff meeting May 8

Tools

• LHC WG2 gitlab

• EFT Interpretation Workflow Twiki page

• Rivet routines that assign STXS bin labels to a given MC event: STXS Rivet code

• PO FeynRules implementation

• EFT
  • Mapping of the STXS to HEL parameters
  • FeynRules implementation of the Warsaw basis (SMEFTsim)

• κ coupling modifiers
  • Latest updates from Yellow Report 4

• STXS.tgz: Revision 8941 of the STXS classification code