COMPOSE-IT: Unitarity for composite models and beyond in the HL-LHC era

27 Jan 2020, 10:00 → 28 Jan 2020, 19:00 Europe/Rome

Aula F (Dipartimento di Fisica e Geologia, Università degli Studi di Perugia)

Valentina Mariani (PG), Simone Biondini (Albert Einstein Center, Institute for Theoretical Physics - Uni Bern), Patrizia Azzi (PD), Orlando Panella (PG), Matteo Presilla (PD), Livio Fano' (PG)

The workshop has the goal to bring together theorists and experimentalists  working actively in the field of fermion composite models and the effective interactions of the hypothetical excited states with the ordinary SM particles. We shall focus on the issue of perturbative unitarity, which has been overlooked in these models, and assess its impact in the related experimental searches.

We plan to discuss such effective models, and possibly affine ones, in connection with the Run III of the LHC and of its forthcoming High-Luminosity and High-Energy options  with respect to possible signatures not yet covered and/or due to new exotic states. 

Organizing Committee: 

Patrizia Azzi (CMS), Simone Biondini, Livio Fanò (CMS), Valentina Mariani (CMS), Orlando Panella, Matteo Presilla (CMS)

 

Compose-it.pdf

Monday, 27 January

1 Review on composite models of excited leptons

Speaker: Orlando Panella (PG)

COMPOSE-IT.key

COMPOSE-IT.pdf

2 Perturbative unitarity bounds for effective composite models

Speaker: Matteo Presilla (PD)

unitarity_PG.pdf

11:20 Coffee break

3 Phenomenology at the LHC of composite particles from strongly interacting Standard Model fermions via four-fermion operators of NJL type

Speaker: She-Sheng Xue

Perugia_2020.pdf

Sub_production_lhc_composite_2nd_JHEP.pdf

4 EFT approach in Dark Matter searches

Speaker: Morgante Enrico

morgante_EFT4DM@LHC.pdf

12:55 Lunch

5 Composite Majorana neutrinos and leptogenesis

Speaker: Simone Biondini (Albert Einstein Center, Institute for Theoretical Physics - Uni Bern)

ECT_Biondini2.pdf

6 Unitarization effects in EFT predictions of VBS at the LHC

Effective field theories are an incredibly powerful tool in order to study and understand the true nature of the symmetry breaking sector dynamics of the Standard Model. However, they can suffer from some theoretical problems such as that of unitarity violation. Nevertheless, in order to interpret experimental data correctly a fully unitary prescription is needed. To this purpose, unitarization methods are addressed, but each of them leads to a different (unitary) prediction. Because of this, there is an inherent theoretical uncertainty in the determination of the effective field theory parameters due to the choice of one unitarization scheme.
In this talk, I will present this uncertainty assuming a strongly interacting electroweak symmetry breaking sector, described by the effective electroweak chiral Lagrangian (or Higgs effective field theory). In particular, I focus on the WZ scattering as the main VBS channel to study the sensitivity to new physics at the LHC. Using various well known unitarization methods, I will show the different predictions at subprocess level, considering the full coupled system of helicity amplitudes. Then I will present the current experimental constraints and how the different predictions manifest in the pp collisions at the LHC. Finally, I will show the corresponding 95% C.L. exclusion regions for the most relevant electroweak chiral Lagrangian parameters involved in the WZ scattering depending on the unitarization method applied.

Speaker: Roberto Morales (Instituto de Física Teórica de Madrid (UAM-CSIC))

RMorales_compose-it.pdf

7 Unitarity Constraints in BSM: new results in the 331 Models

We discuss the main features of the scalar sector of a class of BSM models with enlarged gauge symmetry, the so called 331 Models. The theoretical constraints on the scalar potential such as unitarity, perturbativity and boundedness-from-below, are presented. These results are based on a very-recent analysis that is suitable to be used in phenomenological studies for the exotic scenarios predicted by the 331 Models.

Speaker: Antonio Costantini (Istituto Nazionale di Fisica Nucleare)

Costantini_COMPOSEIT.pdf

15:55 Coffee break

8 Review on exotic physics in CMS

Results from Run 2 and perspective for Run 3

Speaker: LIVIA SOFFI (ROMA1)

COMPOSE-IT2020_V3.pdf

9 Review on exotic physics ATLAS

Results from Run 2 and perspective for Run 3

Speaker: Monica Verducci (ROMA3)

Composeit_Peurgia2020.pdf

20:00 Social dinner

Tuesday, 28 January

10 Excited lepton triplet contribution to electroweak observables at one loop level (TBC)

Speakers: Mario Gomez (Univesidad de Huelva), Muhammad Rehman (Comsats University Islamabad)

11 Present status of LHC and perspectives for Run3 and HL

Evolution of triggers and data analysis tools

Speaker: mia tosi (Universita' degli Studi di Padova)

200128_COMPOSEIT_miatosi.pdf

12 Overview on SM and BSM top quark

Speaker: Alberto Orso Maria Iorio (NA)

Overview on Top Quarks(1).pdf

11:00 Coffee break

13 Review on diboson searches in CMS

Speaker: Alberto Zucchetta (PD)

200128_Zucchetta.pdf

14 Search in ATLAS for excited letpon and dilepton high mass

Speaker: Antonio Sidoti (BO)

excited_leptons_20200114_2.pdf

15 Diboson search in ATLAS

Speaker: Francesco Cirotto (NA)

Diboson_searchesATLAS.pdf

13:15 Lunch

Discussion: Discussion and document preparation