LHC Higgs Working Group

News

* LHCHWG Next General meeting Nov 28 (Mon.) - Nov 30 (Wed.) 2022

Meetings ( InDico page)

Upcoming meetings

Regular meetings

• SC weekly meeting takes place every Friday 17:00-18:00. Please avoid organizing meetings during this time slot if possible.
• Also please avoid having meetings in the morning unless no other choice, to facilitate the participation of our friends from other side of the pond.

Overview

The LHC Higgs Working Group (LHCHWG) was created in January 2010 under the name "LHC Higgs Cross Section Working Group." Its aim was to produce agreements within the LHC community on cross sections, branching ratios and pseudo-observables relevant to SM and MSSM Higgs boson(s).

In spring 2012, the group was restructured and new subgroups were added with the goal of discussing Higgs properties and measurements, as well as BSM extensions. A further restructuring took place in 2014, when the TAC (Theory Advisory Committee) was added to the organization, and an agreement was made with CERN for local support. The TAC always includes one permanent member of the CERN theory group. The activities of the group are supervised by the Steering Committee (SC) that includes two representatives from each experiment and four representatives from the theory community. The SC members from ATLAS or CMS are appointed by each experiment after their internal selection procedures. The SC members from the theory community are appointed by the TAC, in coordination with the SC.

Four CERN Yellow Reports have been completed, "Inclusive Observables" ( CERN-2011- 002), "Differential Distributions" ( CERN-2012-002), "Higgs Properties" ( CERN-2013-004), and "Deciphering the Nature of the Higgs Sector" ( CERN-2017-002). These achievements facilitated the comparison and combination of Higgs results at LHC since the beginning of the LHC physics programme.

Over time, the focus of the working group has widened substantially, so that in November 2020, the majority of its members decided to adjust the name to "LHC Higgs Working Group". The group continues its work to provide recommendations on theoretical predictions and methodologies on Higgs boson(s) studies to the experiments for both current and planned LHC runs. More general aspects related to non-Higgs-boson(s)-specific subjects, like global Effective Field Theories or Dark Matter model studies, will be pursued by the LHCHWG in coordination with other more general efforts of the LHC community.”

If you want to join the working group, please send an e-mail to working group conveners listed below. Please subscribe to the mailing lists of the group.

• CERN support for LHCHWG operation: Guidelines (2014.12.19)

Organization

• Previous organization: 2010-2011, 2012-2013, 2014-2016

Steering Committee Members Mail

Working Group Conveners

• We are organized in 3 working groups.

• Remove SPAMNOT from mailing address when sending.

Sub-group Conveners

(1)This group also has an experimental contact from LHCb: carlos.vazquez@cernNOSPAMPLEASE.ch.

• Remove dummy.name@SPAMNOTcernSPAMNOT.ch or SPAMNOT from mailing address when sending.
• The address should have the prefix "lhc-higgs-" for any kind of mailing lists in our group.
• Any TWiki page Topic name should have the prefix "LHCHWG" and should be created under "LHCHWG" Topic parent.

Contacts with activities outside the Higgs Working Group

Group TWiki	Group Mailing List	Group email to the contacts	ATLAS		CMS		THEORY
BR (WG1)		Mail	Daniela Rebuzzi (Pavia) (08/2014)		Ivica Puljak (Split) (05/2014)		Michael Spira (PSI) (10/2021)	Sven Heinemeyer (IFCA) (08/2014)	Alexander Mück (Aachen) (08/2014)
MCNet (Point of contact)		Mail					Simon Plätzer (University of Graz) 09/2014
PDF (Point of contact)		Mail	Joey Huston* (Michigan State) (01/2010)		Josh Bendavid (CERN)		Maria Ubiali (Cambdridge)	Robert Thorne (UCL) 01/2010	Joey Huston* (Michigan State)
LHC EFT Working Group (Contacts)			Nicolas Berger (Annecy LAPP) (10/2020)		Giovanni Petrucciani (CERN) (10/2020)		Jorge de Blas (Granada) (10/2020)

Theory Advisory Committee

(as from July 1st 2019)

Mode of operation

Introduction

One of the main purposes of the LHCHWG is to provide the experimental collaborations with information in various forms (reference cross sections, benchmarks, recommendations, codes,...). An expression of interest on a specific piece of information may come from experiment of theory (e.g., analysis contact persons, group conveners, or physics coordinators). Such requests should be communicated to the conveners of the working groups WG1-WG3 (collectively referred to as "WGs" in the following). Here we illustrate the guidelines that should be followed to insure a correct and efficient work and communication.

General Principles

• Information on the activities of the LHCHWG should be fully public, open and accessible by anyone, at any time.
• Vertical and horizontal information flow in the LHCHWG should be always guaranteed.
• Calls for action or help should be made in a transparent way, accessible also from outside the LHCHWG.
• Official LHCHWG deliverables are always subject to approval procedures before being publicly available (for details, see below).
• Personal and group focused initiatives as well as external collaborations with other groups should be supported. They should be open to anyone and announced in the mailing list of the WG.

Workflow

Here we outline a "normal" workflow in the LHCHWG. It is understood that in case of doubt, the WG conveners should consult the SC.

1) Submission of requests to the WGs

The conveners of the WGs promote and organize the activities in their groups. In addition, they are the contacts for requests from any internal or external source (e.g., ATLAS/CMS analysis contact persons, group conveners, physics coordinators or other groups like FCC, HL-LHC, or theorists). If the request is considered relevant by the conveners of the appropriate WG, they will define its scope and goals within the WG. If the request is deemed relevant but not-yet-feasible, the WG conveners propose it as an addition to an official LHCHWG wish-list, possibly with a priority grading. Such proposals are communicated to the SC and approved in coordination with the other WG conveners.

2) Publication of the activity and call to the LHCHWG

The WG conveners publish the approved activities (and/or the corresponding call-for-action) on their respective twiki page, with a description of the work to be done, the expected type of deliverables, and the approximated schedule (including a deadline for committing to contribute) and take corresponding actions to gather all the needed expertise from the community. People willing to contribute express their interest to the WG conveners. Depending on the exact request, deliverables are also identified (e.g., tables of numbers to be published on the twiki codes to be made public, lists of available results/codes, documents to appear on the arXiv, etc.).

3) Work is performed

The WG conveners organize the work and collect the results and deliverables. Intermediate status reports can be given upon request from the SC and/or appear on the Twiki of the corresponding WG. Open discussions/meetings are regularly scheduled and announced via the LHCHWG mailing list.

4) Approval of the results

Once results and/or information corresponding to the request is available, the WG conveners inform the SC (typically in the regular SC-WG convener meetings) who either approve it directly or start an approval procedure, the details of which will depend on the actual deliverable. For example, in the case of a document to appear on the arXiv in the name of the LHCHWG (as a whole or by a WG or by smaller groups), a WG-wide (yet light) review procedure will take place.

5) Publication of the results: see detailed discussion on the LHCHWG Library page.

The announcement of new developments in the TH/MC/Tools

"The announcement of new developments in the TH/MC/Tools can be posted on the dedicated Wiki page if the authors consider it relevant for the all LHCHWG groups. The MCnet contact person supervises the corresponding Wiki page and its maintenance. The submission of the news through LHCHWG e-mail lists should be avoided.”

Exchange of non-sensitive experimental information between experiment and theory

For the LHCHWG it is important that Monte Carlo (MC) information, even after detector simulation and with simple kinematic selections applied, may be exchanged between experiment and theory. This information must be non-controversial within the experiments and not compromise their independence. After feedback from the experiments we have defined the following rules in this respect:

(1)
Every figure or numerical information that is supposed to be used or shown in a public document, during a workshop, or a working group meeting requires sign-off by the corresponding collaboration. This also applies if only generator information and no detector simulation were used, as long as the MC is used within (and with the corresponding setup of) the collaboration.

(2)
For written documents, like e.g. notes on arxiv, the collaboration will have to prepare a short document to be circulated among all collaborators for comments and make this document public as well, to provide an official statement by the experiment. Usually such documents include the figures in question, captions that explain what is shown, and potentially some more text to give more specific information, e.g. how exactly a plot has been created. These documents can usually be published on a track of a few weeks. There can be cases though where more discussion within the collaborations may be required.

(3)
There can be a light approval for distributions/information only based on MC and meant to be shown on slides in meetings only. This consists of a sign-off by the Higgs conveners and physics coordination (PC) of the experiments. Depending on the content, the experiments may require an internal approval procedure as described in (2) for notice within the whole collaboration, for three days before approval.

(4)
The light approval ideally should be requested 1-2 weeks before the plots are meant to be shown in public, to give the experiments time to react.

(5)
Private discussions between a limited number of experimentalists and theorists, who would like to exchange material prior to such an approval, e.g. in preparation of a meeting, are allowed. If you plan such a private discussion, people should bring up the case with the corresponding experimental contact of the WG, so that the boundary conditions can be defined. These conditions include e.g.:

• exchange only of generator information (potentially including detector simulation);
• application of simple and well physics-motivated kinematic and/or topological selections;
• information exchange for a confined and well defined purpose and finite time span.

It should be understood that such exchanges are meant to be private and in the small circle of people involved in the specific purpose. The experimental contact of the WG should always be kept in the loop for such exchanges. Once the studies conclude and will be presented in public rules (1)-(4) apply. Two hypothetical examples are given in (*).

In case of remaining questions please contact the SC directly for further advice.

(*)
Example-1:
As follow up of ATLAS or CMS showing a pT distribution with some modeling problems in a meeting, theory colleagues ask for a MC generator level rapidity plot with the same selection, or for the same plot, but after applying some more restrictive generator selection or after changing some generator settings. This type of information can and should be exchanged. After solving the issue, new material illustrating the solution should be approved following rules (1)-(4).

Example-2:
For the discussion of an identified MC issue with experimental material that falls under (1)-(4) in some future meeting, the plots showing the issue can be exchanged with a few colleagues (e.g. generator authors) to ensure that the right type of information is presented in order to ensure an effective discussion.

Higgs cross sections and decay branching ratios

Production cross sections and decay BRs for RUN-2

• Higgs cross sections and BRs in Spread sheet are available here in xlsx format.
• Instruction for Higgs Cross Section Calculation at 13/14 TeV
• Link to the previous recommendations in CERN Report 3 for Higgs XS at 13&14 TeV (link to 7&8 TeV numbers there) and XS for M_H = 125.09 GeV and BR.

SM Higgs

• Recommended values on SM Higgs XS for ggF, VBF, WH, ZH, ttH and tH at 13, 14 and 27 TeV (HL-HE Report)
• Recommended values on SM Higgs XS for ggF, VBF, WH, ZH, ttH bbH and tH at 7 TeV (CERN Report 4)
• Recommended values on SM Higgs XS for ggF, VBF, WH, ZH, ttH bbH and tH at 8 TeV (CERN Report 4)
• Recommended values on SM Higgs XS for ggF, VBF, WH, ZH, ttH bbH and tH at 13 TeV (CERN Report 4)
• Recommended values on SM Higgs XS for ggF, VBF, WH, ZH, ttH bbH and tH at 14 TeV (CERN Report 4)
• Recommended values on SM Higgs XS for ggF, VBF, WH, ZH, ttH bbH and tH for Ecm scan (CERN Report 4)

• Recommended values on SM Higgs XS for HH production (CERN Report 4)

• Recommended values on SM Higgs BR (CERN Report 4)

BSM Higgs

• Recommended values on SM-like Higgs XS for ggF, VBF, WH, ZH, ttH bbH and tH at 7 TeV (CERN Report 4)
• Recommended values on SM-like Higgs XS for ggF, VBF, WH, ZH, ttH bbH and tH at 8 TeV (CERN Report 4)
• Recommended values on SM-like Higgs XS for ggF, VBF, WH, ZH, ttH bbH and tH at 13 TeV (CERN Report 4)
• Recommended values on SM-like Higgs XS for ggF, VBF, WH, ZH, ttH bbH and tH at 14 TeV (CERN Report 4)

• MSSM neutral Higgs: XS scans of the m_A-tanβ plane

Latest plots

• You can find more figures at our gallery here.
• For BSM plots, please look at each XS and BR TWiki page linked above, ex. MSSM Neutral Higgs and MSSM Charged Higgs.
• You can also find useful figures for talks/lectures at European Strategy page.

Figure 1: Standard Model Higgs boson production cross sections at Ecm = 13 and 14 TeV as a function of Higgs boson mass and Higgs boson production cross sections as a function of the centre-of-mass-energies. The tH production cross section accounts for t-ch and s-ch only (no tWH production) [CERN Yellow Report 4].

Figure 2: Higgs boson production cross sections (SM-like coupling, NWA, no EW corrections) at Ecm = 13 and 14 TeV [CERN Yellow Report 4].

Figure 3: Standard Model Higgs boson decay branching ratios [CERN Yellow Report 4].

Figure 4: Standard Model Higgs boson decay branching ratios and total width [CERN Yellow Report 3].

Documents and Practical Guide

Documentation

1. LHC Higgs WG Library
2. Link to CDS
3. Generator setups used * Development only*

CERN Reports: Handbook of LHC Higgs Cross Sections

1. Inclusive Observables ( CERN-2011-002, arXiv:1101.0593).
2. Differential Distributions ( CERN-2012-002, arXiv:1201.3084).
3. Higgs Properties ( CERN-2013-004, arXiv:1307.1347).
   • BibTeX and LaTeX citation format for CERN-2011-002 (arXiv:1101.0593), CERN-2012-002 (arXiv:1201.3084) and CERN-2013-004 (arXiv:1307.1347).
4. Deciphering the Nature of the Higgs Sector ( CERN-2017-002, arXiv:1610.07922).

gitlab, SVN and CDS

LHC H XS WG gitlab

Information on the old SVN (not to be used any longer):

SVN Information	WebSVN
CDS Information	CDS Collection
Instruction for CERN Yellow Report

Communication Tools

How to get CERN Account	CERN Account	How to manage CERN computing account.
InDico	InDico Agenda	Group's workshop and subgroup meeting agenda system.

Mailing List

• The address should have the prefix "lhc-higgs-" for any kind of mailing lists in our group.
• Posting the message is restricted to e-Group member lhc-higgs, i.e. you need to use your e-mail account registered to lhc-higgs mailing list.
• The information below applies to all the lhc-higgs-xxx sub-lists as well.

How to subscribe to Mailing Lists
	address	alias
General	lhc-higgs@SPAMNOTcern.ch		For group's common issues, like announcement of group meeting, meeting summary etc. Can send message to this list from lhc-higgs subscribers. Archived message.
WG1: Higgs XS&BR	lhc-higgs-xsbr@SPAMNOTcern.ch	lhc-higgs-wg1@SPAMNOTcern.ch	WG1: Higgs XS&BR general mailing list. Archived message. Can send message to this list from this WG1 or lhc-higgs subscribers. Inherited from previous lhc-higgs mailing list.
WG2: Higgs Properties	lhc-higgs-properties@SPAMNOTcern.ch	lhc-higgs-wg2@SPAMNOTcern.ch	WG2: Higgs Properties general mailing list. Archived message. Can send message to this list from this WG2 or lhc-higgs subscribers. Inherited from previous lhc-higgs-lm mailing list.
WG3: BSM Higgs	lhc-higgs-bsm@SPAMNOTcern.ch	lhc-higgs-wg3@SPAMNOTcern.ch	WG3: BSM Higgs general mailing list. Archived message. Can send message to this list from this WG3 or lhc-higgs subscribers. Inherited from previous lhc-higgs-hm mailing list.
Steering Committee	lhc-higgs-steering-committee@SPAMNOTcern.ch	lhc-higgs-sc@SPAMNOTcern.ch	For Steering Committee members (restricted access). Can send message to this list from lhc-higgs subscribers.
WG1 Convener	lhc-higgs-xsbr-convener@SPAMNOTcern.ch	lhc-higgs-wg1-convener@SPAMNOTcern.ch	For WG1 conveners (restricted access). Can send message to this list from WG1 or lhc-higgs subscribers.
WG2 Convener	lhc-higgs-properties-convener@SPAMNOTcern.ch	lhc-higgs-wg2-convener@SPAMNOTcern.ch	For WG2 conveners (restricted access). Can send message to this list from WG2 or lhc-higgs subscribers.
WG3 Convener	lhc-higgs-bsm-convener@SPAMNOTcern.ch	lhc-higgs-wg3-convener@SPAMNOTcern.ch	For WG3 conveners (restricted access). Can send message to this list from WG3 or lhc-higgs subscribers.
Subgroup Convener	lhc-higgs-xsbr-subgroup-convener@SPAMNOTcern.ch		For Subgroup conveners (restricted access). Can send message to this list from lhc-higgs subscribers and others.
Announcements	lhc-higgs-announcements@SPAMNOTcern.ch		For Higgs-related announcements not directly related to the WG activities, like conferences, programs, etc. Every member of the Higgs working group is welcome to (responsibly) use this list. Need to be a member of this list to send messages.

Mattermost channels

Mattermost team "LHC Higgs WG" and channels are provided for less formal communication and discussions - one can join the this Mattermost team at this link: LHC Higgs WG team.

Each member of this team can join any of the public channels for individual working groups and HH cross-group: WG1, WG2, WG3, HH cross-group.

In addition, there are private Mattermost channels used for the communication between SC members and WG conveners, and "annual" public channels used for the discussions during the annual general assembly of the LHC Higgs WG (channels are prepared, used and then archived yearly).

Workshops

The 18th General Assembly Meeting 2021	Dec. 1-3, 2021	Home page	Agenda
The 17th General Assembly Meeting virtual-only 2020	Nov. 9-11, 2020	Home page	Agenda
The 16th General Assembly Meeting at CERN 2019	Oct. 16-18, 2019	Home page	Agenda
The 15th General Assembly Meeting at CERN 2018	Dec. 10-12, 2018	Home page	Agenda
The 14th General Assembly Meeting at CERN 2018	Mar. 26-27, 2018	Home page	Agenda
The 13th General Assembly Meeting at CERN 2017	Jul. 13-14, 2017	Home page	Agenda
The 12th General Assembly Meeting at CERN 2016	Oct. 12-14, 2016	Home page	Agenda
Preparatory Meeting	July 7-8, 2016	Home page	Agenda
The 11th General Assembly Meeting at CERN 2016	Jan. 13-15, 2016	Home page	Agenda
The 10th General Assembly Meeting at CERN 2015	July 15-17, 2015	Home page	Agenda
The 9th General Assembly Meeting at CERN 2015	January 22-24, 2015	Home page	Agenda
The 8th General Assembly Meeting at CERN 2014	June 12-13, 2014	Home page	Agenda	Minutes
The 7th Workshop at CERN 2012	Dec. 5-6, 2012	Home page	Agenda
The 6th Workshop at CERN 2012	May 24-25, 2012	Home page	Agenda
The 5th Workshop at LAL 2011	Nov. 21-22, 2011	Home page	Agenda
The 4th Workshop at BNL 2011	May 4-6, 2011	Home page	Agenda
The 3rd Workshop at Bari 2010	Nov. 4-5, 2010	Home page	Agenda
The 2nd Workshop at CERN 2010	Jul. 5-6, 2010	Home page	Agenda	Minutes
Inauguration Workshop in Freiburg 2010	Apr. 12-13, 2010	Home page	Agenda	Minutes

• Higgs_XSBR_YR4_update.xlsx: Higgs XS&BR Update (CERN Report 4, 2016)