IRN Terascale @ Laboratori Nazionali di Frascati

15 avr. 2024, 12:00 → 17 avr. 2024, 17:00 Europe/Paris

Auditorium B. Touschek (Laboratori Nazionali di Frascati)

Ana M. Teixeira (LPC Clermont), Emanuele Angelo Bagnaschi (CERN/INFN Laboratori Nazionali di Frascati), Marie-Helene Genest (LPSC-Grenoble, CNRS/UGA (FR)), Roberto Franceschini (CERN)

 

We are looking forward to welcoming you to the spring meeting of the IRN Terascale at LNF, April 15-17th 2024.

The International Research Network (IRN) Terascale is a groupement de recherche of the IN2P3 dedicated to the experimental and theoretical aspects of the search for new physics at the TeV scale.

The research program focuses on three core areas: "Higgs and electroweak symmetry breaking", "Beyond the Standard Model" and "Dark Universe". Moreover, it includes a fourth working group dedicated to "Method and Tools".

The network is formed of both french and European partners. In the roman area there are two nodes: INFN Laboratori Nazionali di Frascati (represented in the scientific management committee by Emanuele Bagnaschi) and U. Roma Tre (represented by Roberto Franceschini).

Meetings of the network are usually organized on a bi-annual basis, and are used to share the research activity of the network, and to foster collaboration between the nodes.

The program is organized in different sessions, corresponding to the focus topics of the IRN.

For any questions regarding the corresponding session, please contact the group conveners:

Higgs and EW physics	Iro Koletsou, Nicolas Morange, Christophe Ochando, Pietro Slavich
BSM	Eric Chabert, Björn Herrmann, Romain Madar, Jérémie Quevillon
Dark Universe	Julien Masbou, Emmanuel Moulin, Kallia Petraki, Federico Mescia
Methods and Tools	Anja Butter, Samuel Calvet, Sabine Kraml

More information at terascale.in2p3.fr

 

Zoom 15 April

Join Zoom Meeting
https://infn-it.zoom.us/j/99401597971?pwd=OVpjdzJzV1EwWXpvOWhuYlMvQ2M1QT09

Meeting ID: 994 0159 7971
Passcode: 039903

__________________________________________________________
 

Zoom 16 April

Join Zoom Meeting
https://infn-it.zoom.us/j/92300708702?pwd=OTVvN2ZsQThSMmQwRTZaaTRxL1ZvQT09

Meeting ID: 923 0070 8702
Passcode: 319711

__________________________________________________________
 

Zoom 17 April

Join Zoom Meeting
https://infn-it.zoom.us/j/93787837407?pwd=VlJSSnZmMCt5SFgyZndNdU9QRWVTZz09

Meeting ID: 937 8783 7407
Passcode: 614448

 

__________________________________________________

 

mappa_LNF.pdf

Privacy_Policy_EN.pdf

SCHEDA-COMPORTAMENTALE-EN.pdf

WiFi SSID INFN instructions for events.pdf

lundi 15 avril

13:30 → 14:30 Lunch break

14:30 → 16:10 Beyond the Standard Model

14:30 Overview and challenges of semi-leptonic B decays and implications for new physics

We discuss the status of b→sℓ+ℓ− decays in the post-RK(∗) era. We present a model-independent analysis of the b→sℓ+ℓ− data and investigate the implications of the different sets of observables. Special emphasis will be given to the theoretical uncertainties and challenges.

Orateur: Nazila Mahmoudi (Lyon University)

Nazila_IRN_April2024.pdf

14:55 New Constraint for Isotropic Lorentz Violation from LHC Data

New calculations for the kinematics of photon decay to fermions in vacuo under an isotropic violation of Lorentz invariance (LV), parameterized by the Standard-Model Extension (SME), are presented in this paper and used to interpret prompt photon production in LHC data. The measurement of inclusive prompt photon production at the LHC Run 2, with photons observed up to a transverse energy of 2.5 TeV , provides the lower bound $\tilde{\kappa}_{\mathrm{tr}} > -1.06 \times 10^{-13}$ on the isotropic coefficient $\tilde{\kappa}_{\mathrm{tr}}$ at 95% confidence level. This result improves over the previous bound from hadron colliders by a factor of 55. The calculations for the kinematics of photon decay have further potential use to constrain LV coefficients from the appearance of fermion pairs, for instance, top-antitop.

Orateur: David Amram (IP2I)

AMRAM_IRN2024.pdf

15:20 The rise and fall of light stops in the LHC top quark sample

We discuss the possibility that light new physics in the top quark sample at the LHC can be found by investigating with greater care well known kinematic distributions, such as the invariant mass $m_{bl}$ of the $b$-jet and the charged lepton in fully leptonic $t\bar{t}$ events. We demonstrate that new physics can be probed in the rising part of the $\textit{ already measured}$ $m_{bl}$ distribution. To this end we analyze a concrete supersymmetric scenario with light right-handed stop quark, chargino and neutralino. The corresponding spectra are characterized by small mass differences, which make them not yet excluded by current LHC searches and give rise to a specific end-point in the shape of the $m_{bl}$ distribution. We argue that this sharp feature is general for models of light new physics that have so far escaped the LHC searches and can offer a precious handle for the implementation of robust searches that exploit, rather than suffer from, soft bottom quarks and leptons. Recasting public data on searches for new physics, we identify candidate models that are not yet excluded. For these models we study the $m_{bl}$ distribution and derive the expected signal yields, finding that there is untapped potential for discovery of new physics using the $m_{bl}$ distribution.

Orateur: Dibyashree Sengupta (INFN, Laboratori Nazionali di Frascati)

IRN_2024_final.pdf

15:45 Closing in on new chiral leptons at the LHC

We study the phenomenological viability of chiral extensions of the Standard Model, with new chiral fermions acquiring their mass through interactions with a single Higgs. We examine constraints from electroweak precision tests, Higgs physics and direct searches at the LHC. Our analysis indicates that purely chiral scenarios are perturbatively excluded by the combination of Higgs coupling measurements and LHC direct searches. However, allowing for a partial contribution from vector-like masses opens up the parameter space and non-decoupled exotic leptons could account for the observed 2σ deviation in h→Zγ. This scenario will be further tested in the high-luminosity phase of the LHC.

Orateur: Marco NARDECCHIA (Sapienza Università di Roma)

LNF_2024_MN.pdf

16:10 → 16:40 Coffee break

16:40 → 18:20 Beyond the Standard Model

16:40 Unraveling Dark Matter and neutrino mysteries with a scotogenic approach

We present a study of a scotogenic model addressing the dark matter problem while generating three non-zero neutrino masses. We investigate the dual nature of a dark matter candidate emerging from distinct particle components across diverse energy regimes within the energy range of HL-LHC. Results highlight the behavior of the dark matter candidate in varied energy contexts, with a focus on correlations with neutrino masses. Furthermore, we will pay attention to experimental constraints, particularly from lepton flavor violating observables, delivering a comprehensive overview of the model's implications for advancing our understanding of fundamental particles.

Orateur: Ugo de Noyers (LAPTh / Université Savoie Mont Blanc)

DE_NOYERS_IRN_Frascati.pdf

17:05 Novel Weinberg-like operators from new scalar multiplets

The Weinberg operator, the unique dimension-5 effective operator LLHH, can generate tiny Majorana masses for neutrinos. In the presence of new scalar multiplets acquiring vacuum expectation values (VEVs), novel Weinberg-like operators emerge, subsequently contributing to Majorana neutrino masses. We consider scenarios involving one or two new scalars transforming under higher SU(2) representations $\mathcal{R}$, up to $\mathcal{R}\leq 5$. We start our analysis from an Effective Field Theory approach and subsequently investigate potential tree-level UV completions for the newly introduced dimension-5 operators.

Orateur: Simone Marciano (INFN - Università Roma Tre)

IRNterasclaleMarciano24.pdf

17:30 Modular Symmetry: a new perspective on the Flavor Puzzle

Understanding the flavour structure of leptons, i.e. their mass pattern and mixing, is a major unresolved puzzle in theoretical particle physics. In the recent past, a substantial effort went into models based on discrete flavour symmetries, but that approach proved to be particularly challenging. In 2017 a new promising direction was suggested: a “bottom-up” approach based on modular invariance, a more predictive framework which may be able to provide testable predictions for incoming neutrino experiments. It is important to highlight both the strengths and the potential shortcomings of this new perspective. As an example, a recent model based on the modular group $\Gamma_2\cong S_3$ will be presented (JHEP09(2023)043).

Orateur: Matteo Parriciatu (Università degli Studi Roma Tre)

Matteo_Parriciatu_IRN_Terascale.pdf

17:55 The Baryon Asymmetry from Supercooled Confinement

Orateur: Jacopo Nava (University of Bologna)

JacopoNava_IRN_Terascale.pdf

18:20 → 19:00 Scientific management committee meeting

IRN SMC meeting Apr 2024.pdf

mardi 16 avril

09:30 → 11:10 Methods and tools

09:30 Local Analytic Sector Subtraction: a Numerical Implementation

Within the framework of the Local Analytic Sector Subtraction we briefly present the method for removing infrared singularities at Next-to-Leading Order (NLO) in QCD for processes involving massless coloured particles either in the initial or in the final state. We present an extension of Local Analytic Sector Subtraction to the case involving massive emitter. This process also allows us to test the efficiency and stability of our numerical implementation, and, in this sense, a comparison with other existing tools has been performed.

Orateur: Giovanni Limatola

Limatola_IRN.pdf

09:50 Probabilistic theory uncertainties from missing higher orders

I present a probabilistically founded definition of theory uncertainties in perturbative computations due to the unknown higher orders. I show its performance against canonical recipes such as scale variation. I finally discuss future directions.

Orateur: Marco Bonvini (INFN Roma)

bonvini_Terascale2024.pdf

10:10 The inclusion of QED correction in the NNPDF4.0 fitting framework

The need of percent precision in high energy physics requires the inclusion of QED effects in theoretical predictions, for example like the contributions coming from photon initiated processes. It is trivial then, to correctly determine the photon content of the proton.
In this work, we extend the NNPDF4.0 NNLO determination of parton distribution functions (PDFs) with a photon PDF, determined within the LuxQED formalism, which evolves with the gluon and quark PDFs via DGLAP equations that contain NLO QED corrections.
We study the impact of the QED effects to the NNPDF4.0 methodology, we compare our results with NNPDF3.1QED and other recent QED PDF fits and we asses the impact of the photon PDF for photon-initiated processes for LHC processes.

Orateur: Niccolò Laurenti (University of MIlan and INFN)

frascati24_laurenti.pdf

10:30 The inclusion of theory uncertainties in NNLO and N3LO NNPDF fits

We include uncertainties due to missing higher order corrections to QCD computations (MHOU) used in the determination of parton distributions (PDFs) in the recent NNPDF4.0 set of PDFs. We use our previously published methodology, based on the treatment of MHOUs and their full correlations through a theory covariance matrix determined by scale variation, now fully incorporated in the new NNPDF theory pipeline. We assess the impact of the inclusion of MHOUs on the NNPDF4.0 central values and uncertainties. We also show how this formalism can be used to produce approximate N3LO PDF sets, using N3LO ingredients when they are known and assessing the impact of the unknown ingredients through a theory covariance matrix.

Orateur: Andrea Barontini (University of Milan)

Rome_IRN2024.pdf

10:50 The Impact of Theory Uncertainties in Global EDM Analyses

We investigate the impact of theory uncertainties on a global EDM analysis in the low-energy sector. For this analysis, we employ SFitter as our tool of choice. In contrast to previous analyses, in the EDM sector, theory uncertainties are heavily contingent upon the model parameters and thus cannot be disentangled from the prediction as readily as for SMEFT global analyses.

Orateur: Nina Elmer (Heidelberg University)

IRNFrascati_EDM.pdf

11:10 → 11:40 Coffee break

11:40 → 13:15 Methods and tools

11:40 Kicking it Off(-shell) with Direct Diffusion

Off-shell effects in large LHC backgrounds are crucial for precision predictions and, at the same time, challenging to simulate. We show how a generative diffusion network learns off-shell kinematics given the much simpler on-shell process. It generates off-shell configurations fast and precisely, while reproducing even challenging on-shell features.

Orateur: Sofia Palacios Schweitzer (ITP, Heidelberg University)

Rom_SofiaPalaciosSchweitzer.pdf

12:00 Modern Machine Learning Tools for Unfolding

Unfolding is a transformative method that is key to analyze LHC data. More recently, modern machine learning tools enable its implementation in an unbinned and high-dimensional manner. The basic techniques to perform unfolding include event reweighting, direct mapping between distributions and conditional phase space sampling, each of them providing a way to unfold LHC data accounting for all correlations in many dimensions. We describe a set of known and new unfolding methods and tools and discuss their respective advantages. Their combination allows for a systematic comparison and performance control for a given unfolding problem.

Orateur: Javier Mariño Villadamigo (Institut für Theoretische Physik - University of Heidelberg)

MarinoJavier_IRNTerascale24.pdf

12:20 Exploring evaluation methods for generative models in HEP

Deep generative models have emerged as a powerful paradigm for enhancing and maximising the potential for discovery at collider experiments. They can be deployed for multiple tasks, including fast simulations, data augmentation and anomaly detection. As novel methods continue to be developed, there is a pressing need to advance techniques for model selection and evaluation, particularly in high-dimensional scenarios. Such studies are crucial in a precision-driven field like high-energy physics. In this presentation, I will discuss some recent work in this direction, focusing on normalising flows, a popular class of methods for density estimation that allows both sampling and evaluation by construction.

Orateur: Marco Letizia (MaLGa Center, University of Genoa and INFN)

Terascale_MarcoLetizia.pdf

12:40 Probing dark matter models with DarkPACK: present state and future developments

Nowadays, the research in Beyond Standard Model (BSM) scenarios aimed at describing the nature of dark matter is a very active field. DarkPACK is a recently released software conceived to help to study such models. It can already compute the relic density in the freeze-out scenario, and its potential can be used to compute other observables.

Orateur: MARCO PALMIOTTO (Université Claude Bernard Lyon 1)

presentation_irn.pdf

13:15 → 13:30 Group photo

13:30 → 14:30 Lunch break

14:30 → 16:00 Dark universe

14:30 The COSINUS experiment: utilizing cryogenic NaI crystals for direct dark matter detection

The COSINUS (Cryogenic Observatory for SIgnatures seen in Next-generation Underground Searches) experiment is a state-of-the-art cryogenic initiative in the field of dark matter direct detection. Operating at millikelvin temperatures and utilizing ultrapure NaI detectors, COSINUS employs a two-channel readout system utilizing transition edge sensors (TESs), allowing for effective particle discrimination. COSINUS aims to independently verify the DAMA/LIBRA dark matter signal. Conducted at the Laboratori Nazionali del Gran Sasso in Italy, COSINUS will contribute crucial insights into the global pursuit of understanding dark matter's unknown properties. This talk will go through the latest results, updates on ongoing efforts, and perspectives for the future.

Orateur: Mariano Cababie

COSINUS@IRNTerascale2024.pdf

14:50 Status and prospects of the SABRE experiment for Dark Matter search in the two hemispheres

SABRE aims to deploy arrays of ultra-low background NaI(Tl) crystals to carry out a model-independent search for dark matter through the annual modulation signature. SABRE will be a double-site experiment, made up of two separate detectors which rely on a joint crystal R&D activity, located in the North (LNGS) and South hemisphere (SUPL). SABRE has carried out, since more than 10 years, an extensive R&D on ultra radio-pure NaI(Tl) crystals. Several crystals have been grown and tested in active and passive shields at LNGS. Based on these results SABRE North is proceeding to a full scale design with purely passive shielding. To reach an unprecedented level of radiopurity for NaI(Tl) crystals, SABRE is exploiting zone refining purification of the NaI powder prior to growth. We will present the status of SABRE North installation at LNGS, and recent results from the R&D towards the ultimate radio purity achievable for the crystals.

Orateur: Tomei Claudia (INFN Roma)

Terascale_SABRE_Tomei.pdf

15:10 Search for Light-Feebly Interacting Particles with the PADME experiment

The elusive nature of dark matter has prompted innovative and open-minded experiments across a broad spectrum of energies employing high-sensitivity detectors, but despite the numerous attempts none has yielded up to now any evidence [1]. Inserted into this landscape is the Positron Annihilation into Dark Matter Experiment (PADME) at the Laboratori Nazionali di Frascati of INFN [2].

PADME is currently investigating a Dark Photon signal by analyzing the missing-mass spectrum of single photon final states resulting from positron annihilation events on electrons within a fixed target. The PADME approach not only enables the search for a Dark Photon signal but also allows for the exploration of any new particle produced in $e^+ e^-$ collisions, including long-lived Axion-Like-Particles (ALPs), proto-phobic X bosons, Dark Higgs, and more.

Significantly, the PADME setup offers the unique opportunity to validate or disprove the particle nature of the X17 anomaly observed in ATOMKI nuclear physics experiments that study the de-excitation via Internal Pair Creation of light nuclei [3]. The data-taking conducted by the PADME collaboration during 2022 was conceived to collect approximately 10^11 positrons-on-target, 10^10 for each of the 47 beam energy values ranging from 262 to 298 MeV, in order to produce resonantly the X17. This fine energy scan aims to identify the reaction $e^+ e^-\rightarrow X17 \rightarrow e^+ e^-$.

The talk will provide an overview of the experiment's scientific program and the ongoing data analyses.

References
[1] P. Agrawal et al., Eur. Phys. J. C 81 (2021) 11, 1015.
[2] P. Albicocco et al., JINST 17 (2022) 08, P08032.
[3] L. Darmé et al., Phys. Rev. D 106 (2022) 11, 115036.

Orateur: Paola Gianotti (LNF - INFN)

GianottiTeraScale2024.pptx

15:30 The Cygno experiment

In the last decades, the existance of dark matter (DM) has become one of the key elements of modern physics. Direct evidence of this exotic form of matter can be found by searching for extremely rare nuclear recoils of regular matter with energy of the order of few keV. The peculiar motion of the Earth around the centre of the Galaxy induces a strongly anisotropical structure in the angular distribution of the recoils. Thus, the measurement of the directional information would greatly benefit this field of research, by providing a better tool to positively claim for a DM discovery than only-energy sensitve detectors, and allowing to reject scattering induced by neutrinos, making directional detectors the only viable option to deeply venture into the neutrino fog. The CYGNO experiment follows this innovative path by developing a high-precision gaseous Time Projection Chamber to exploit the advantages of a directional detector in the rare event search field, such as few GeV DM. A large demonstrator of the final detector is going to be installed at the Gran Sasso National Laboratories (LNGS) and consists in a TPC filled with He:CF4 gas mixture operating with a triple GEM amplification stage. The gas scintillating properties allow the realization of an optical readout which comprises photomultiplier tubes and extremely low-noise granular sCMOS camera sensors.We will present the characteristics of the directional TPC focusing on the set of information on the recoil tracks it can provide. In addition, we will present the latest results of the underground operation at LNGS of a 50 l, 50 cm prototype.

Orateur: Giorgio Dho (INFN - LNF)

Slide_CYGNO.pdf

15:45 Recent results and future perspective in the search for Axion dark matter at LNF.

In ecent years, we witnessed an increasing growth in the research of light Dark Matter (DM) candidates, addressing in particular axions and axion-like particles (ALPs). If axions are found to exist, they would untie the long-standing DM problem, after being originally postulated as a solution to the strong CP problem. The nature of a pseudoscalar, electrically neutral and feebly interacting particle make the axion a
strong DM candidate, and its cosmological evolution and astrophysical constraints indicate a favorable mass range between 1 μeV < m_a < 10 meV.
The axion observation technique is based upon its inverse Primakoff conversion into one photon, stimulated by a static magnetic field. The essential elements required to run a haloscope are a superconducting magnet to generate a strong magnetic field, a microwave resonant cavity where the electromagnetic field excitation builds up, an ultra-low noise receiver, a tuning mechanism to scan over the axion mass range and a cryogenic system to grant operation at low temperature.
We report on the first operation of the new QUAX haloscope located at the National Laboratories of Frascati (LNF). The experiment is conducted using a resonant cavity equipped with a tuning rod mechanism allowing to exclude the existence of dark matter axions with coupling gaγγ down to 0.861 × 10−13 GeV−1 in the mass window (36.5241 − 36.5510) μeV. We also report on future development in that haunt for axions showcasing the features of FLASH (FINUDA magnet for Light
Axion SearcH ), a future experiment that will be host at
LNF.

Orateur: Alessandro D'Elia (LNF- INFN)

slides_D'Elia.pdf

slides_D'Elia.pptx

16:00 → 16:30 Coffee break

16:30 → 18:30 Dark universe

16:30 Axion emission from strange matter in core-collapse SNe

Axion emission is known to be strongly constrained by neutrino-burst data from SN 1987A. Compton-like nucleon-pion to nucleon-axion scattering has recently been shown to be an important mechanism, due also to the large baryon densities involved. We perform a first quantitative study of the role of hadronic matter beyond the first generation -- in particular strange matter. We consistently include the full baryon and meson octets in axion emission from Compton-like scattering and from baryon decay. We consider a range of supernova thermodynamic conditions as well as various motivated scenarios for the axion-quark couplings. Irrespective of either modelling aspect, we find that axion emissivity introduces non-trivial correlations between flavour-diagonal axial couplings and constrains the off-diagonal, flavor-violating counterpart. This constraint can be as small as O(10^{-2}) for the QCD axion, i.e. for f_a = 10^9 GeV.

Orateurs: Diego Guadagnoli (LAPTh Annecy), Maël Cavan-Piton (LAPTh Annecy)

Cavan_Frascati.pdf

16:46 Dark Matter Direct Detection in t-channel mediator models

We propose a comprehensive study of the Direct Detection phenomenology of singlet Dark Matter $t$-channel portal models. For that purpose, we present a complete computation of the loop induced direct detection cross-section for both scalar and fermionic Dark Matter candidates. We complete the study comparing the results with current and future bounds from Direct Detection experiments and requiring the correct Dark Matter relic density.

Orateur: David Cabo Almeida (University of Messina (Italy))

Cabo-Almeida_IRN_v1.pdf

17:02 Model-Independent Radiative Symmetry Breaking: Gravitational Waves, Primordial Black Holes and New Physics

First-order phase transitions, which take place when the symmetries are predominantly broken (and masses are then generated) through radiative corrections, produce observable gravitational waves and primordial black holes; also, if observed, they would signal new physics. I discuss a model-independent approach that is valid for large-enough supercooling to quantitatively describe these phenomena in terms of few parameters, which are computable once the model is specified. Among other things, I identify regions of the parameter space that correspond to the background of gravitational waves recently detected by pulsar timing arrays and others that are either excluded by the observing runs of LIGO and Virgo or within the reach of future gravitational wave detectors. These include LISA, BBO and DECIGO, which will test the TeV scale. Furthermore, I show regions of the parameter space where primordial black holes produced by large over-densities due to such phase transitions can account for dark matter. Finally, if time allows, I discuss how this model-independent approach can be applied to specific cases, including a phenomenological completion of the Standard Model with right-handed neutrinos and gauged B - L undergoing radiative symmetry breaking of the electroweak symmetry and B - L.

Orateur: Alberto Salvio (University of Rome and INFN Tor Vergata)

salvio.pdf

17:18 Improved bounds on the hot QCD axion

The QCD axion is the most robust explanation to the strong CP problem and provides a good dark matter candidate. A population of QCD axions can be produced in the early universe via scattering with SM particles, and can be searched for in cosmological datasets. I will present the state-of-the-art bound on the minimal QCD axion model by confronting momentum-dependent Boltzmann equations, from axion-pion scattering below the QCD cross-over, against up-to-date measurements of the CMB and abundances from BBN. Finally, I will present forecasts using dedicated likelihoods for future cosmological surveys and a new sphaleron rate from unquenched lattice QCD.

Orateur: Giovanni Grilli Di Cortona (INFN - Laboratori Nazionali di Frascati)

Grilli_hotQCDaxion.pdf

17:34 On the Proof of Chiral Symmetry Breaking from Anomaly Matching in QCD-like Theories

Confining QCD-like sectors are often present in BSM phenomenology. We critically reconsider the argument based on 't Hooft anomaly matching that aims at proving chiral symmetry breaking in 4d confining QCD-like theories with $N_c>2$ colors and $N_f$ flavors. We provide a detailed proof and clarify under which (dynamical) conditions the historical approach of $N_f$-independence holds, as a property of the solutions of the anomaly matching and persistent mass equations. The validity of $N_f$-independence was assumed in previous works based on qualitative arguments, but it was never proven rigorously. Then, we furnish a novel strategy, called `downlifting', that allows to prove chiral symmetry breaking for any $N_f\geq p_{min}$, where $p_{min}$ is the smallest prime factor of $N_c$. Contrary to earlier attempts, our results do not rely on ad-hoc assumptions on the spectrum of massless bound states. The proof can be extended to $N_f

Orateur: Marcello Romano (IPhT, CEA, CNRS, Université Paris-Saclay)

Presentation_ChSB_Terascale_2 (2).pdf

17:50 Accidentally light scalars and inflation

Scalar fields can be accidentally light if symmetries forbid their tree-level masses in the potential at the renormalizable level. We present some example models with small symmetry groups (typically SU(n) x U(1)) but with the scalars transforming in large representations. We discuss possible applications to generating natural hierarchies of scales in models with elementary scalars. In particular, we present a model of hybrid natural inflation where the inflaton potential is flat because it is an accidentally light scalar.

Orateur: Félix BRUEMMER (LUPM Montpellier)

fr24.pdf

19:15 → 19:45 Transfer to the restaurant

19:45 → 21:45 Social dinner in Frascati

social-dinner-IRN-terascale.pdf

mercredi 17 avril

10:00 → 11:15 Higgs and EW

10:00 Feynman integrals in QFT

In this talk, I will review theoretical and phenomenological aspects of multi-loop amplitudes, focusing on the their wide range of physical applications. I will gently introduce the method employed in the calculation of the gg -> HH NLO SM and Beyond cross section to show where Feynman integrals enter, and where calculation bottleneck may arise.
The increasing mathematical understanding of Feynman integrals brought impact on fields from higher-order perturbative QFT predictions to Cosmology and Classical Gravity.
I will introduce some of the main state-of-the-art methods for evaluating Feynman integrals, and I will show how such object are connecting a broad spectrum of techniques from differential geometry, differential equation, machine learning and numerical approaches.
In conclusion, I will show some applications of these methods on scattering processes of phenomenological interest, like q \bar q -> t \bar t virtual amplitude contribution at NNLO.

Orateur: JONATHAN RONCA

IRCatTerascale_Ronca.pdf

10:25 A Cosmological Solution to the Doublet-Triplet Splitting Problem

We propose a model that can solve simultaneously the doublet-triplet splitting problem of grand unified theories, the electroweak hierarchy problem and the strong CP problem. The mechanism is based on the dynamics of two light scalars that can crunch the universe at the QCD phase transition if triplets are light or if the doublets are heavy or do not have a vev. The same mechanism was previously discussed as an explanation for the small value of the weak scale and of the QCD θ-angle. The two problems are solved also in our context by the same dynamics that explains the splitting between Higgs doublets and triplets. The only traces left at low energies are two light axion-like particles weakly coupled to the Standard Model.

Orateur: Pablo Sesma (IPhT Saclay)

PABLO SESMA FRASCATI.pdf

10:50 Electroweak W±Z production measurement at √𝑠=13 TeV with the ATLAS detector and an EFT interpretation.

Orateur: Eirini Kasimi (Aristotle U., Thessaloniki)

Terascale_presentation_Kasimi_new.pdf

11:15 → 11:45 Coffee Break

11:45 → 13:05 Higgs and EW

11:45 Exploring Higgs Boson Properties: Insights from the ATLAS Group at LNF

Since the discovery of the Higgs boson, the ATLAS group at LNF has been studying its properties, particularly in the four-lepton decay channel. Known as the “golden channel,” this process played a crucial role in the discovery of the Higgs boson in 2012 and continues to be one of the primary final states for precise measurements of its properties, such as mass, spin/CP, and couplings with other Standard Model (SM) particles. These studies aim also to identify possible deviations from the SM and signs of New Physics. The state-of-the-art research on the Higgs boson in the four-lepton channel will be discussed, focusing on studies conducted by the LNF group, along with an outlook on future prospects.

Orateur: Chiara Arcangeletti (INFN-LNF)

IRN_Arcangeletti2.pdf

12:10 Top mass uncertainties in double Higgs production

I will discuss the uncertainties due to the top-mass renormalization scheme allowing the trilinear Higgs boson self-coupling to vary around its Standard Model value including parton shower effects.

Orateur: Giuseppe Degrassi (Universita' Roma Tre, INFN sez. Roma Tre)

IRNFrascati.pdf

12:35 Higgs prospects at the FCC-ee

Orateur: Nicolas Morange (IJCLab)

2024-04-17_HiggsProspects_FCCee.pdf

13:05 → 13:10 Famous last words

13:10 → 13:30 Free time for networking/collaboration

13:30 → 15:00 Lunch break