Les Houches Workshop Series == Physics at TeV Colliders and Beyond the Standard Model == Session: 12 to 30 June 2023

Aim and Format

This series of workshops, started 20 years ago, aims  to bring together theorists and experimentalists working on the phenomenology of  TeV colliders with an emphasis on the physics at the LHC. The highlight of the 2019 Les Houches Edition is to take full advantage of the data that has been collected at the LHC so far and prepare for the future runs. With this much data, following the discovery of a Higgs-like particle, one aim of this workshop is how to best sharpen our tools and techniques in order to reconstruct the profile of this particle and possibly uncover New Physics. An equally important aim is to reassess some of the still open fundamental questions in the light of this discovery and investigate which kind of New Physics such a particle may be hinting at. The importance of precision measurements on the one hand and precision calculations and simulation on the other hand is central. In the light of the LHC results, a reflection on the strategy in HEP and prospects from future facilities (at high and low energy) should be conducted. In view of the above considerations, the Workshop will devote particular attention to:

(i) Higgs physics, and how it shapes our view on the mechanism of electroweak symmetry breaking; (ii) related searches for New Physics and (iii) progress in new techniques for the calculations and simulation of Standard Model processes.

The Workshop will address issues such as how to best exploit these data as well as how to prepare for future LHC data, and what is most desirable in LHC upgrades. These activities will be conducted in close connection with the development and improvements of related theory tools, in particular of Monte-Carlo event generators. The role of machine learning and artificial intelligence will be part of these new development.

The Workshop runs over one year, including two meetings in Les Houches in the month of June, and exchanges and collaborations before and after the meetings. The meetings in Les Houches will consist of two sessions:

Session I: 10-19 June 2019
with emphasis on SM-related issues.

Session II: 19-28 June 2019
  with emphasis on New-Physics searches

WG Topics

Themes to be covered in the Workshop range from Quantum ChromoDynamics to the mechanism of Electroweak Symmetry Breaking to Higgs Physics, models of New Physics and their phenomenology. Four Working Groups  have been set up covering these different aspects of the Physics at the LHC, the division into Working Groups being in many cases artificial − think of the interdependence between New-Physics signals and their respective backgrounds as the simplest example. We thus expect and aim towards very strong connections between these groups.

• SM and NLO Multi-leg WG. It will be concerned about the theoretical predictions for multileg processes, including beyond leading order, and the possibility of implementing these calculations in Monte Carlos. This WG aims at a cross breeding between novel approaches (twistors, unitarity cuts,...) and improvements in standard techniques. Particular attention will be devoted to electroweak corrections, to NLO Monte Carlo implementations and improvements, and to NNLO computations. A further topic to cover are new developments in the physics of jets (boosted objects, substructure,...) and how to exploit machine learning techniques. Many topics covered by this subgroup have a direct connection to precision Higgs physics as well as to New Physics (background but also boosted objects). This WG will convene during the first Les Houches session.
  
  
• Higgs WG. The task of this WG is twofold. A first concern is precision calculations and precision measurements together with improvements in search techniques and strategies. The aim is to arrive at a better reconstruction of the Higgs profile. A second concern is how Higgs physics constrains New Physics, either directly by the information it provides for particle searches, or indirectly by its role in, e.g., flavour-physics, or its connection with Dark Matter. The first task will be covered during Session I, in overlap with the activities of the SM and NLO Multi-leg WG. The second task will be addressed during Session II in close connection with the New Physics WG.
  
  
• New Physics WG. A central question is how the Higgs-like signal may be used as guidance for models of New Physics and what is the role of Naturalness.  Further issues will include model reconstruction and model-independent searches based on topologies as well as the connection with Dark Matter and the impact from astrophysics and cosmology − especially in consideration of the fresh data flowing from this field. This WG will convene during the second Les Houches session.
  
  
• Tools and Monte Carlos WG. This WG will liaise with the SM and New Physics WGs, with the task (i) of incorporating in these simulation tools new ideas, novel techniques and new models discussed in the other WG's (ii) of setting standards and accords among the simulation codes to better meet the experimental needs. Issues concerning pdf's and jets will also be covered within this WG, that will run throughout the two sessions. In session I the emphasis will be on SM issues, in close connection with the SM/NLO Working Group, while in session II the emphasis will be on the implementation of new techniques to extract and implement new physics or set limits on generic models. The use of machine learning tecniques is another opic. 

It should be clear from these considerations that, in the spirit of the Les Houches PhysTev series, we expect a strong interplay and collaboration between the different groups and their subgroups. The projects are to start in February 2019  and should be completed by the end of the year 2019.

The meeting at les Houches, between June 10th and June 28, 2019, will be the central point of the Workshop. Here, in addition to the Working Group activities, a few lectures and review talks are planned. Participation to the Workshop is open to all. However, due to space limitation in Les Houches, attendance to the meeting is limited to 70 participants at any given point. Due to the overwhelming response of the past  sessions, PhysTeV Les Houches 2019 is over a period of almost 3 weeks. Though we expect a few participants to be able to attend the meeting in its full duration, plans will be made so that a roughly equal number of participants cover the first or the second half of the meeting.

Coordination with other Workshops

Coordination with other Workshops may be taking place

• Higgs as a Probe of New Physics, 18-22 February 2019, Osaka, Japan.    

The Les Houches Centre for Physics is located in the French Alps, about an hour from Geneva and an hour from Annecy. The Centre has a tradition of organising Schools, Workshops and Conferences for more than five decades now and boasts an excellent library. For the purpose of this Workshop a special computing system will be installed.