QCD@Work - International Workshop on QCD - Theory and Experiment

18 giu 2024, 08:00 → 21 giu 2024, 19:00 Europe/Rome

Palazzo delle Arti Beltrani (Trani - Italy )

23028945.jpg

EPJ-logo.png

group-1

group-2

group-3.jpg

group-4

group-5

group-6

IMG_2627.jpg

IMG_2628.jpg

privacy.pdf

trani1-smalll.jpg

trani3-small.jpg

Trani_Cattedrale1.jpg

martedì 18 giugno

08:00 → 09:00 Registrations

09:00 → 09:30 Welcome

09:30 → 10:50 Session 1

Coordinatore: Pietro Colangelo (Istituto Nazionale di Fisica Nucleare)

09:30 The legacy of Marcello Ciafaloni and Stefano Catani

Relatore: Giovanni Ridolfi (Istituto Nazionale di Fisica Nucleare)

ridolfi-trani.pdf

10:00 QCD measurements with ATLAS

The ATLAS experiment has performed a range of QCD measurements. The recoil of the Z-boson is sensitive to quark and gluon emissions and is used to determine the strong coupling constant in a novel approach. Measurements of transverse energy-energy correlation in multijet events are compared to state-of-the-art NLO and NNLO predictions.used to determine the strong coupling constant. Jet cross-section ratios between inclusive bins of jet multiplicity are measured differentially in variables that are sensitive to either the energy-scale or angular distribution of hadronic energy flow in the final state. Several improvements to the jet energy scale uncertainties are described, which result in significant improvements of the overall ATLAS jet energy scale uncertainty. The measurements are compared to state-of-the-art NLO and NNLO predictions. Finally, we present fits to determine parton distribution functions (PDFs) using a diverse set of measurements from the ATLAS experiment at the LHC in combination with deep-inelastic scattering data from HERA.

Relatore: Eimear Conroy (University of Oxford (GB))

atlas-QCD@Work_talk.pdf

10:30 A general mass variable flavor number scheme for Z boson associated with a heavy quark production at hadron colliders

The general mass variable flavor number (GMVFN) scheme S-ACOT-MPS will
be discussed for proton-proton collisions. The impact of heavy-flavor
contributions within this factorization scheme will be shown for the production
of a $Z$ boson in association with a charm/bottom quark in pQCD.
An amended version of the QCD factorization formula for proton-proton collisions will
be discussed as well as the role of $Z+c/b$ production at the LHC in constraining
heavy-flavor PDFs. Phenomenological applications will be presented.

Relatore: Marco Guzzi (Kennesaw State University)

MGuzzi-SACOT-MPS-QCD@work24.pdf

MGuzzi-SACOT-MPS-QCD@work24.pptx

10:50 → 11:30 Coffee break

11:30 → 13:00 Session 2

Coordinatore: Giuseppe Eugenio Bruno (Istituto Nazionale di Fisica Nucleare)

11:30 QCD critical point, fluctuations and hydrodynamics

Recent developments aimed at mapping QCD phase diagram and the search for the QCD critical point in heavy-ion collisions will be described.

Relatore: Mikhail Stephanov (UIC)

stephanov-qcdwork-2024-slides.pdf

12:00 Exploring QGP Signatures in Small System: Insights from ALICE in Pb-Pb and pp Collisions

At LHC energies, signatures typically attributed to quark-gluon plasma (QGP) formation have been observed in small collision systems such as pp and p-Pb. In particular, observables such as transverse-momentum spectra, azimuthal anisotropy in particle production, strangeness enhancement and baryon-over-meson ratios, exhibit behaviors resembling heavy-ion collisions. These observables depend strongly on the final-state charged-particle multiplicity. The high-multiplicity triggered data from pp collisions in Run 2, and the new data collected with the upgraded ALICE detector in Run 3 enabled precise measurements in this context. This contribution will present recent results based on pp collisions, including particle production, differential studies of strangeness, baryon-to-meson ratios, and anisotropic flow. Furthermore, comparisons with results in Pb-Pb collisions will be conducted to outline the limits of QGP formation.

Relatore: Rajendra Nath Patra (Istituto Nazionale di Fisica Nucleare)

Rajendra_QCD@Work_2024_Insight_QGP_small_system.pdf

12:20 Hagedorn temperature in confining gauge theories from holography

Relatore: Francesco Bigazzi (Istituto Nazionale di Fisica Nucleare)

Bigazzi.pdf

12:40 Dense QCD matter and neutron stars from holography

I will present the latest results on phases and properties of matter at large baryon densities using holographic methods. I will focus on the Witten-Sakai-Sugimoto model, where baryonic matter as well as quark matter and more exotic phases such as quarkyonic matter can be studied. In particular, I will discuss results for isospin-asymmetric matter and the construction of neutron stars from holography, including a dynamic calculation of the crust and the crust-core transition.

Relatore: Andreas Schmitt (University of Southampton)

schmitt.pdf

13:00 → 15:00 Lunch

15:00 → 16:10 Session 3

Coordinatore: Donato Maria Creanza (Istituto Nazionale di Fisica Nucleare)

15:00 LHCb highlights

Relatore: Federico Betti

15:30 Hyperon Physics at BESIII

With large datasets of $J/\psi$ and $\psi(3686)$ resonances collected at BESIII through electron-positron annihilation, highly precise polarization measurements and studies on the properties of entangled hyperon-antihyperon pairs are available. The BESIII collaboration has recently presented a series of analyses on the transverse polarization measurements in the processes of $J/\psi$ and $\psi(3686)$ decaying into $\Lambda\bar\Lambda$, $\Sigma\bar{\Sigma}$, and $\Xi\bar\Xi$. The weak decay parameters are independently determined in both hyperon mode and antihyperon mode, guided by the non-zero polarization. A direct CP conservation test can then be conducted with the hyperon-antihyperon decay parameters.

Relatore: Jingxu Zhang

ReportQCD@Work2024.pdf

15:50 Inclusive rare $\Lambda_b$ decays to photon

I present an analysis of the inclusive $H_b \to X_s \gamma$ decay with $H_b$ a beauty baryon, in particular $\Lambda_b$, employing an expansion in the heavy quark mass at ${\cal O}(m_b^{-3})$ at leading order in $\alpha_s$.
For a polarized baryon I show the results for the distribution $\displaystyle\frac{d^2\Gamma}{dy \, d \cos \theta_P}$, with $y=2E_\gamma/m_b$, $E_\gamma$ the photon energy and $\theta_P$ the angle between the baryon spin vector and the photon momentum in the $H_b$ rest-frame.
I discuss the correlation between the baryon spin and the photon polarization, and show how effects of physics beyond the Standard Model can modify the photon polarization asymmetry.
I also present a method to treat the singular terms in the photon energy distribution.

Relatore: Francesco Loparco (Istituto Nazionale di Fisica Nucleare)

Francesco_Loparco_Trani_QCDatWork.pdf

16:10 → 16:40 Coffe break

16:40 → 18:10 Session 4

Coordinatore: Claudio Coriano' (Istituto Nazionale di Fisica Nucleare)

16:40 Topology of the large-N expansion in SU(N) Yang-Mills theory and spin-statistics theorem

Relatore: Marco Bochicchio (Istituto Nazionale di Fisica Nucleare)

M.BochicchioQCD@work2024.pdf

17:10 Feynman Integral: Synergies Between Particle Physics and Gravitational Waves

The calculation of scattering amplitudes in particle physics heavily relies on Feynman integrals. One of the key properties of these integrals is that they obey linear relations, enabling the simplification of scattering amplitude calculations. Specifically, they are used for decomposing the amplitudes into a basis of functions called master integrals and evaluating them using differential equations. By exploring the vector space structure of Feynman integrals and utilizing intersection theory, a more comprehensive understanding of their characteristics can be obtained. Additionally, these integrals have practical applications in the field of gravitational wave physics, where precise observables can be obtained by leveraging the techniques developed in particle physics. In this talk, we will discuss the structure of Feynman integrals and highlight their crucial role in advancing both particle physics and gravitational wave physics.

Relatore: Manoj Kumar Mandal (Istituto Nazionale di Fisica Nucleare)

Manoj_QCD@work.pdf

17:30 Holographic renormalized Entanglement and entropic $c-$function

We compute holographic entanglement entropy (EE) and the renormalized EE in AdS solitons with gauge potential for various dimensions. The renormalized EE is a cutoff-independent universal component of EE. Via Kaluza-Klein compactification of $S^1$ and considering the low-energy regime, we deduce the $(d-1)$-dimensional renormalized EE from the odd-dimensional counterpart. This corresponds to the shrinking circle of AdS solitons, probed at large $l$. The minimal surface transitions from disk to cylinder dominance as $l$ increases. The quantum phase transition occurs at a critical subregion size, with renormalized EE showing non-monotonic behavior around this size. Across dimensions, massive modes decouple at lower energy, while degrees of freedom with Wilson lines contribute at smaller energy scales.

Relatore: Mitsutoshi Fujita (University of South China)

presen_EE_Italy_MFujita.pdf

17:50 Parity-odd CFT and quantum anomalies

Chiral and conformal anomalies stand as pivotal phenomena spanning multiple disciplines, including high-energy physics, condensed matter theory and cosmology. These anomalies, crucial in understanding fundamental interactions, manifest through divergences and traces of correlation functions. In this study, we delve into these phenomena within the framework of Conformal Field Theory (CFT), elucidating their intricate structure and implications. Specifically, we focus on the role of conformal Ward identities in fully characterizing the parity-odd interactions associated with chiral and conformal anomalies in momentum-space. By examining these phenomena through the lens of CFTs, we gain deeper insights into their mathematical underpinnings and their significance across diverse physical contexts.

Relatore: Stefano Lionetti (Istituto Nazionale di Fisica Nucleare)

presentazione.pdf

18:30 → 21:00 Guided visit to Trani

mercoledì 19 giugno

09:00 → 11:00 Session 5

Coordinatore: Gabriele Chiodini (Istituto Nazionale di Fisica Nucleare)

09:00 Forward Higgs production: a challenge in high-energy perturbative QCD

The forward production of a Higgs boson in proton-proton collisions can be
described within high-energy QCD factorization. The key ingredient is the so-called Higgs impact factor, whose calculation in the next-to-leading order for infinite top mass turned out to be very challenging.

Relatore: Alessandro Papa (Università della Calabria & INFN-Cosenza)

trani.pdf

09:30 CMS Experimental Results

Relatore: Maitreyee Mukhejee (Panjab University Chandigarh)

10:00 Next-to-leading power corrections to event shape variables

We investigate the origin of next-to-leading power corrections to the event shapes thrust and $c$-parameter, at next-to-leading order.
For both event shapes we trace the origin of such terms in the exact
calculation, and compare with a recent approach involving
the eikonal approximation and momentum shifts that follow from the Low-Burnett-Kroll-Del Duca theorem. We assess the differences both analytically and numerically.For the $c$-parameter both exact and approximate results are expressed in terms of elliptic integrals, but near the elastic limit it exhibits patterns similar to the thrust results.

Relatore: Shubham mishra (IIT Hyderabad)

QCD@work_Shubh.pdf

10:20 Precision measurements with kaon and pion decays at CERN

The NA62 experiment at CERN collected the world's largest dataset of charged kaon decays in 2016-2018, leading to the first measurement of the branching ratio of the ultra-rare $K^+ \rightarrow \pi^+ \nu \bar\nu$ decay, based on 20 candidates.
In this talk NA62 reports new results from the analyses of rare kaon and pion decays, using data samples collected in 2017-2018. A sample of $K^+ \rightarrow \pi^+ \gamma \gamma$ decays was collected using a minimum-bias trigger, and the results include measurement of the branching ratio, study of the di-photon mass spectrum, and the first search for production and prompt decay of an axion-like particle with gluon coupling in the process $K^+ \rightarrow \pi^+ A$, $A \rightarrow \gamma \gamma$. A sample of $\pi^0 \rightarrow e^+ e^-$ decay candidates was collected using a dedicated scaled down di-electron trigger, and a preliminary result of the branching fraction measurement is presented. Recent results from analyses of $K^+ \rightarrow \pi^0 e^+ \nu \gamma$ and $K^+ \rightarrow \pi^+ \mu^+ \mu^-$ decays using 2017--2018 datasets are also presented. The radiative kaon decay $K^+ \rightarrow \pi^0 e^+ \nu \gamma$ (Ke3g) is studied with a data sample of O(100k) Ke3g candidates with sub-percent background contaminations. Results with the most precise measurements of the Ke3g branching ratios and T-asymmetry are presented. The $K^+ \rightarrow \pi^+ \mu^+ \mu^-$ sample comprises about 27k signal events with negligible background contamination, and the presented analysis results include the most precise determination of the branching ratio and the form factor.
The first observation of the decay $K^\pm \rightarrow \pi^0 \pi^0 \mu^\pm \nu$ (K00$\mu$4) by the NA48/2 experiment at the CERN and the final measurement of the branching ratio are also presented. The result is converted into a first measurement of the R form factor in Kl4 decays and compared with the prediction from 1-loop Chiral Perturbation Theory.

Relatore: Andrea Bizzeti (Istituto Nazionale di Fisica Nucleare)

qcd_at_work_2024_bizzeti.pdf

11:00 → 11:30 Coffee break

11:30 → 13:00 Session 6

Coordinatore: Fulvia De Fazio (Istituto Nazionale di Fisica Nucleare)

11:30 Flavour News from my Homeoffice

Relatore: Andrzej Buras (TUM)

Trani0624.pdf

12:00 Recent results from Belle II experiment

Relatore: Antonio Passeri (Istituto Nazionale di Fisica Nucleare)

Passeri-QCD@work.pdf

12:30 FCNC Decays of Spin-1/2 Double Heavy Baryons to Spin-3/2 Single Heavy Baryons

In recent years, there have been many discoveries in the spectroscopy of hadrons containing heavy quarks. Almost all baryons containing a single heavy quark are discovered in experiments. The quark model predicts the existence of many baryons with double heavy quarks. Among the possible double heavy baryons, only $\Xi^{+}_{cc}$ and $\Xi^{++}_{cc}$ have been experimentally observed in LHCb.
Flavor-changing neutral current (FCNC) processes represent a promising platform for precise testing of SM as well as looking for new physics beyond the SM.
In this study, the weak decays of spin-1/2 double heavy baryons to spin-3/2 single heavy baryons induced by FCNC are studied within the light cone QCD sum rules method. First, the transition form factors of $\Xi_{bb}^{0,-} \rightarrow \Xi_b^{*{0,-}} \bar \ell \ell$, $\Xi_{bb}^{0,-} \rightarrow \Sigma_b^{*{0,-}} \bar \ell \ell$, $\Xi_{cc}^{++,+} \rightarrow \Sigma_c^{*{++,+}} \bar \ell \ell$, $\Omega_{bb}^{-} \rightarrow \Xi_b^{*{-}} \bar \ell \ell$, $\Omega_{bb}^{-} \rightarrow \Sigma_b^{*{-}} \bar \ell \ell$, $\Omega_{cc}^{+} \rightarrow \Xi_c^{*{+}} \bar \ell \ell$ decays are calculated. Then by using the results for the form factors, the corresponding decay widths are estimated.

Relatore: Emre Askan (Middle East Technical University)

Emre_Askan_QCDatWork2024.pdf

13:00 → 15:00 Lunch

15:00 → 16:30 Session 7

Coordinatore: Floriana Giannuzzi (Istituto Nazionale di Fisica Nucleare)

15:00 BES III highlights

Relatore: Isabella Garzia (Istituto Nazionale di Fisica Nucleare)

Garzia_QCD-at-Work.pdf

15:30 Study of charmonium decays to $K^0_S K \pi$ in the $B \to (K^0_S K \pi) K$ channels

A study of the $B^+ \to K^0_SK^+K^-\pi^+$ and $B^+ \to K^0_SK^+K^+\pi^-$ decays is performed using proton-proton collisions at center-of-mass energies of 7, 8 and 13 TeV at the LHCb experiment. The $K^0_SK\pi$ invariant mass spectra from both decay modes reveal a rich content of charmonium resonances. New precise measurements of the $\eta_c$ and $\eta_c(2S)$ resonance parameters are performed and branching fraction measurements are obtained for $B^+$ decays to $\eta_c$, $J/\psi$, $\eta_c(2S)$ and $\chi_{c1}$ resonances. In particular, the first observation and branching fraction measurement of $B^+ \to \chi_{c0} K^0 \pi^+$ is reported as well as first measurements of the $B^+ \to K^0_SK^+K^-\pi^+$ and $B^+ \to K^0_SK^+K^+\pi^-$ branching fractions. Dalitz plot analyses of $\eta_c \to K^0_S K \pi$ and $\eta_c(2S) \to K^0_S K \pi$ decays are performed. A new measurement of the amplitude and phase of the $K \pi$ S-wave as functions of the $K \pi$ mass is performed, together with measurements of the $K^*_0(1430)$, $K^*_0(1950)$ and $a_0(1700)$ parameters. Finally, the branching fractions of $\chi_{c1}$ decays to $K^*$ resonances are also measured.

Relatore: Antimo Palano (Istituto Nazionale di Fisica Nucleare)

antimo_palano_qcdwork_2024.pdf

15:50 A holographic approach to heavy non $q\bar{q}-$ states using configurational entropy

This work uses the connection between hadronic stability and configurational entropy to explore hadronic structures written in terms of nonquadratic dilaton $(\kappa\,z)^{2-\alpha}$. These hadronic structures are described using the relation between the parameters $\kappa$ and $\alpha$ with the constituent mass. We test $Z_c$ and $\psi$ as non $q\bar{q}$ states defined as hadroquarkonium, hadronic molecule, or diquark-antidiquark pair. We find that photographically speaking, $Z_c$ is better described as a hybrid meson and $\psi$ as hadrocharmonium.

Relatore: Miguel Angel Martin Contreras (University of South China)

non_qqbar_states-MAMC.pdf

16:30 → 18:00 Poster session with snacks and coffee

16:30 Silica aerogel characterization for the ePIC dRICH detector

The ePIC detector is specifically designed to address the entire physics program
at the Electron-Ion Collider (EIC). It consists of several sub-detectors, each tailored
to address specific physics channels. One of the key sub-systems of ePIC is
the dual-radiator Ring Imaging Cherenkov (dRICH) detector, which is a highmomentum
particle-identification system located in the hadronic end-cap. For
this purpose, silica aerogel has been chosen as a solid radiator. The optical and
geometrical characteristics of the aerogel tiles play a critical role in enhancing
the particle identification performance. Intensive R&D efforts are currently underway
to optimize these properties. Ongoing studies are focused on defining and
refining the aerogel tiles to ensure optimal performance. The measurement of the
transmittance of several aerogel tiles with different refractive indices, including
the setup and the measurement method, will be presented.

Relatore: Anna Rita Altamura (INFN - Bari)

16:31 Characterization of Monolithic Active Pixel Sensors for future collider experiments.

Authors
Francesco Barile$^{1,2}$, Giuseppe Eugenio Bruno$^{1,2}$, Angelo Colelli$^{1,2}$, Domenico Di Bari$^{1,2}$, Shyam Kumar$^{2}$, Cosimo Pastore$^{2}$, Rajendra Nath Patra$^{2,3}$, Triloki Triloki$^{1,2}$

$^{1}$University of Bari - Department of Physics DIF, Bari, Italy
$^{2}$INFN of Bari, Bari, Italy
$^{3}$Department of Physics, University of Jammu, Jammu, India
Abstract
In high-energy physics experiments, Monolithic Active Pixel Sensors (MAPS) have become crucial components of vertex and tracking detectors over the past decade due to the integration of readout circuitry with the detection volume in a single chip.
The low material budget requirement to achieve precise tracking and vertexing capabilities for upgrade of HEP experiments such as ALICE at LHC and future experimental facilities like ePIC at EIC, leads a direct attention towards an ultra-thin (a few tens of µm), bent, wafer-scale silicon sensors produced with stitching technology.
Recent ongoing activities performed at the INFN and UniBa Laboratory in Bari will be described. The characterization of analogue silicon pixel sensors of 65 nm CMOS technology using electrical test pulsing and $^{55}$Fe as a soft X-ray source will be discussed. Furthermore, a study on timing performance will be presented.

Relatore: Angelo Colelli (Istituto Nazionale di Fisica Nucleare)

poster_Characterization_MAPS_future_collider_expts_QCD_Trani_Colelli.pdf

16:32 Symplectic quantization: a new deterministic approach to the dynamics of quantum fields inspired by statistical mechanics

The present work is about a new method to sample the quantum fluctuations of relativistic fields by means of a pseudo-Hamiltonian dynamics in an enlarge space of variables. The proposed approach promotes the fictitious time of Parisi-Wu stochastic quantisation to a true physical parameter controlling a deterministic dynamics. The sampling of quantum fluctuations is guaranteed by the presence of new additionational conjugated momenta, which reprents the rate of variation of ordinary fields with respect to the newly added time variable. The main goal of this approach is to provide a numerical method to sample quantum fluctuations of fields directly in Minkowski space, whereas all existent methods allowed one so far to do this only in Euclidean space, therefore loosing important physics. From the pseudo-Hamiltonian dynanamics one is then able, assuming ergodicity, to retrieve the Feynman path integral as the Fourier transform of a pseudo-microcanonical partition function. The whole framework proposed is not only the source of a new numerical approach to study quantum fields but also and most importantly reveals important connections between quantum field theory, statistical mechanics and Hamiltonian dynamics. Here we will discuss the main ideas behind the formalism and the first successful results of numerical tests, as well as the difficulties we encountered. (Preprint: https://arxiv.org/abs/2403.17149)

Relatore: Martina Giachello (Istituto Nazionale di Fisica Nucleare)

16:33 Study of long distance contributions in the exclusive rare radiative B_c decay

The rare decays of the $B_c$ meson induced by the flavour changing neutral current $c \to u$ transition are strongly suppressed by the Glashow-Iliopoulos-Maiani mechanism in SM. Therefore, they exhibit sensitivity to new physics effects, as long as the impacts from long-distance contributions can be controlled. The difficulty is to get rid of these hadronic effects. I will present a study of such effects in radiative $B_c$ transitions both to $B$  and to the axial-vector $B_1^{\prime}$ mesons, aiming to determine which channel offers better potential for probing new physics.

Relatore: Nicola Losacco (Istituto Nazionale di Fisica Nucleare)

poster.pdf

16:35 Various Illustrative Brief Glimpses at the Flavour-Cryptoexotic Tetraquark Mesons

Constituting the largest fraction of all multiquark states observed by experiment, tetraquark mesons carrying overall quark flavour quantum numbers identical to those of conventional quark–antiquark mesons necessitate their particularly careful phenomenological treatment. A collection of (more or less recent) insights specific to the latter subset of exotic hadrons promises to enable significant improvements in the understanding of these states by theoretical approaches such as, for instance, the formalism of QCD sum rules.

Relatore: Wolfgang LUCHA (Austrian Academy of Sciences)

16:36 The Gravitational Form Factor of the Pion and the Conformal Anomaly

This poster examines the interplay between the conformal trace anomaly and the gravitational form factor of the pion within the framework of Quantum Chromodynamics (QCD). By focusing on the 1-loop calculation, we investigate the non-abelian TJJ three-point function and TJJJ four-point function. These calculations provide information on the contributions arising from the conformal trace anomaly to the gravitational form factors, providing insights into the underlying dynamics of the strong interactions.

Relatori: Dario Melle (INFN Lecce), Riccardo Tommasi (Istituto Nazionale di Fisica Nucleare)

16:38 Physics program of ALICE 3: a next-generation heavy-ion detector for LHC Run 5 and beyond

The ALICE Collaboration is proposing a completely new apparatus, ALICE 3, for the LHC Runs 5 and 6. The detector comprises a large pixel-based tracking system covering eight units of pseudorapidity, complemented by various particle identification systems including silicon time-of-flight layers, a ring-imaging Cherenkov detector, a muon identification system, an electromagnetic calorimeter and a forward conversion tracker. ALICE 3 will, on the one hand, enable novel studies of the quark-gluon plasma (QGP) and, on the other hand, open up important physics opportunities in other areas of QCD and beyond. The main new studies in the QGP sector focus on low-𝑝$_𝑇$ heavy-flavour production, including beauty hadrons, multi-charm baryons and charm-charm correlations, as well as on precise multi-differential measurements of dielectron emission to probe the mechanism of chiral-symmetry restoration and the time-evolution of the QGP temperature. Besides QGP studies, ALICE 3 can uniquely contribute to hadronic physics, with femtoscopic studies of the interaction potentials between charm mesons and searches for nuclei with charm, and to fundamental physics, with tests of the Low theorem for ultra-soft photon emission. This contribution will cover the detector concept and the latest projections for the resulting physics performance.

Relatore: Nicola Nicassio (Istituto Nazionale di Fisica Nucleare)

Poster_QCDatWork_final_reduced.pdf

16:39 Thermal field fluctuations in a chiral lagrangian with broken scale invariance

We study the finite temperature equation of state by using an effective lagrangian in which a dilaton field reproduces the breaking of scale symmetry in QCD. We start by extending a previous investigation in the pure gauge sector, where the dynamics of the gluon condensate, expressed in terms of a dilaton lagrangian, is dominated below the critical phase transition temperature, while at greater temperatures the condensate evaporates in the form of quasi-free gluons [1]. In this context, we study the role of the inclusion of thermal fluctuations of the dilaton field and compare our results with the lattice QCD data. Moreover, we take into account of the meson sector at zero chemical potential by means of an effective lagrangian which incorporates broken scale in addition to spontaneously broken chiral symmetry [2]. Beyond the mean-field approximation, the relevance of the thermal fluctuations of the scalar glueball, other than the contribution of the σ and π meson fields, is considered following the general technique proposed in Ref. [3]. In this framework, we investigate the thermodynamic nature of the phase transition, in presence and in absence of explicit chiral symmetry breaking.
[1] A. Drago, M. Gibilisco, C. Ratti, Nucl. Phys. A 742, 165 (2004)
[2] G.W. Carter, P.J. Ellis, S. Rudaz, Nucl. Phys. A 618, 317 (1997)
[3] A. Mocsy, I.N. Mishustin, P.J. Ellis, Phys. Rev. C 70, 015204 (1997)

Relatore: Luca Passarella

16:59 Electro-Weak Phase Transitions in a Dark Matter Scenario

This research investigates the consequences of first-order phase transitions in the early Universe, specifically in extensions of the Standard Model that include dark matter. The study focuses on a scenario based on a dark SU(2) group and provides a case study for assessing the sensitivity of future gravitational wave signals from phase transitions in connection with the phenomenology of dark matter. To ensure consistency with experimental results, constraints are applied to the parameter space of the model.

Relatore: Maimoona Razzaq (University of Calabria & INFN Cosenza)

Maimoona Razzaq (QCD@Work).pdf

17:00 Holographic phases of QCD

In this presentation, we will discuss the QCD phase diagram at finite temperature and finite baryon chemical potential using a holographic AdS/QCD model. We study backreacted bulk gravity solutions with appropriate boundary conditions representing strongly interacting nuclear matter, deconfined quarks, and various possible condensates in a spectrum of chemical potentials and temperatures.

Relatore: Akash Singh (IISER Mohali (India))

POSTER_QCD_WORK_AKASH.pdf

17:02 Cwebs in multiparton scattering amplitudes

Soft function exponentiates in terms of the Soft anomalous dimension; the Feynman diagrams contributing to it are called Cwebs. The colour and kinematics of a Cweb mix via a web mixing matrix -- calculation of web mixing matrices at higher loop orders is a nontrivial task using the replica trick, and a long-awaited aim is to construct these matrices, bypassing the replica trick.
Our works contribute to both of these goals: To provide a more efficient algorithm to implement the replica trick, and to develop formal approaches to direct construction of these matrices. I will discuss our novel approach to Fused-Web along with the Uniqueness theorem, which facilitates the calculation of diagonal blocks of web mixing matrices without using the replica trick. Further, I will discuss the progress made in the direction of explicit calculation of web mixing matrices and conclude with the results at four loops, along with some all-order predictions.

Relatore: Aditya Srivastav (Indian Institute of Technology Hyderabad)

giovedì 20 giugno

09:00 → 11:00 Session 9

Coordinatore: Eugenio Nappi (Istituto Nazionale di Fisica Nucleare)

09:00 Hadronic contribution to the muon g-2: theoretical challenges with the MUonE experiment

Relatore: Fulvio Piccinini (Istituto Nazionale di Fisica Nucleare)

piccinini.pdf

09:30 Recent results in hadron spectroscopy from CMS

In this poster the latest results from the CMS experiment at the LHC on the observation of new structures in the J/ψJ/ψ mass spectrum in events from proton-proton collisions at √s = 13 TeV. The data, collected during Run 2 of the LHC, correspond to an integrated luminosity of 135 fb-1. The results are compared to analogous searches performed at the LHC by the LHCb and ATLAS experiments. This study contributes to our understanding of exotic states involving heavy quarks.

Relatore: Vincenzo Mastrapasqua (Istituto Nazionale di Fisica Nucleare)

QCD@Work-1.pdf

09:50 Tetraquarks in two-dimensional QCD

Relatore: Prof. Hagop Sazdjian (Université Paris-Saclay, IJCLab)

sazdjian-wqcd24.pdf

10:10 Exotic charmonium production in heavy ion collisions

Relatore: Fernando Navarra (Institute of Physics , University of São Paulo, Brazil)

qcd24-navarra.pdf

10:30 Rapidity-only evolution of TMDs

The most known scheme to regulate the rapidity/UV divergences of the Transverse Momentum Distribution operators due to the infinite light-like gauge links is the Collis Soper Sterman formalism or the Soft Collinear Effective Theory formalism. An alternative procedure is provided by the scheme used in the small-x physics. The corresponding evolution equations differ already in leading order. Because of the future Electron-Ion Collider accelerator, which will probe the TMDs at values of the Bjorken x in the region between small-$x_B$ to $x_B\sim 1$, the different formalisms need to be reconciled. I will discuss the conformal properties of TMD operators and present the result of the conformal rapidity evolution of TMD operators in the Sudakov region.
In particular, I will present the calculation of the scale of the coupling constant obtained using the BLM procedure.

Relatore: Giovanni Antonio Chirilli (University of Salento)

QCDatWork24-chirilli.pdf

11:00 → 11:30 Coffee break

11:30 → 13:00 Session 10

Coordinatore: Salvatore My (Università degli Studi di Bari and INFN)

11:30 Exploring the QCD frontier with ePIC at EIC

Relatore: Silvia Dalla Torre (Istituto Nazionale di Fisica Nucleare)

DallaTorre_QCD@work_TRANI_20240618-21.pdf

12:00 Transverse Lambda polarization in semi-inclusive DIS, e+e- and pp collisions and the TMD polarizing fragmentation function

Relatore: Francesco Murgia (Istituto Nazionale di Fisica Nucleare)

FMURGIA-QCD@Work2024.pdf

12:30 Low Energy description of single flavor baryons

In the case of a single quark flavor, the ordinary low-energy Skyrme description of baryons is not available. I will describe, in the context of a holographic model, how such a description can be given in terms of "Hall droplet sheets". In the case of a dark QCD-like sector, these baryons can be related to domain walls and cosmic strings.

Relatore: Aldo Lorenzo Cotrone (Istituto Nazionale di Fisica Nucleare)

QCD@work2024.pdf

13:00 → 15:00 Lunch

15:00 → 16:50 Session 11

Coordinatore: Stefano Nicotri (Istituto Nazionale di Fisica Nucleare)

15:00 Polarization in relativistic heavy ion collisions

Relatore: Francesco Becattini (Istituto Nazionale di Fisica Nucleare)

becattini.pdf

15:30 Spin Alignment of Vector Mesons Induced by Quark Spin Density Fluctuations

In recent years, spin polarization of hyperons and the spin alignment of vector mesons were observed by STAR in 20%-60% centrality collision, where the large angular momentum and the magnetic field were supposed to be the main reasons. However, in the most central collision with collision energy 200GeV, the rotation, magnetic field as well as the baryon number should vanish, spin alignment was also observed. Thus, it still remains challenge to explain the experimental data.

In this talk, I will present a new mechanism for the spin alignment of vector mesons: the spin density fluctuation. It is found that the spin alignment of vector meson is sensitive to the spin of constituent strange but is independent of the sign of the spin density, i.e., whether there is more spin-ups than spin-downs or vice versa, the same spin alignment of vector will be obtained. And due to interactions between quarks, especially the tensor and axial-vector interaction, the local spin density will not stay exact zero due to the fluctuation. Thus, though there is no global spin polarization of quarks, local spin density fluctuation will result in none zero spin alignment of vector meson. It is also found that the quark interactions induced by (anti-)instanton could be the source of spin alignment of phi and K^{*0} mesons.

Relatore: Kun Xu (University of Chinese Academy of Sciences)

KunXu-SpinAlignment-Trani.pdf

15:50 Heavy-flavour production as a function of event activity in pp collisions with the ALICE experiment

Due to their large masses, the production of heavy quarks can be perturbatively computed, thus providing a powerful tool to test the corresponding QCD calculations. Additionally, heavy-flavour measurements are useful to reveal the details of heavy-quark fragmentation in pp collisions at LHC energies. Event-activity-dependent measurements of heavy-flavour production may shed light on the mechanisms of interplay between soft and hard processes such as the role of multi-parton interactions. The excellent tracking and vertexing capabilities of the ALICE detector, as well as its particle identification performance over a wide momentum interval, enable accurate measurement and identification of heavy-flavour particles down to low transverse momenta via reconstruction of their hadronic decay channels.

In this contribution, we present recent measurements of the ALICE experiment on charm production as a function of charged-particle multiplicity in pp collisions at various energies, including measurements of the charm baryon-to-meson production yield ratios. New results of D$^0$ production as a function of the transverse spherocity of the event, as well as of the transverse event-activity classifier $R_{\rm T}$, are also presented.

Relatore: László Gyulai (Wigner RCP, Budapest)

Gyulai_QCDWork.pdf

16:10 Superconducting multi-vortices and a novel BPS bound in chiral perturbation theory

We derive a novel BPS bound from chiral perturbation theory minimally coupled to electrodynamics at finite isospin chemical potential. At a critical value of the isospin chemical potential, a system of first-order differential equations for the gauge field and the hadronic profile can be derived from the requirement to saturate the bound. These BPS configurations represent magnetic multi-vortices with quantized flux supported by a superconducting current. The corresponding topological charge density is related to the magnetic flux density, but is screened by the hadronic profile. Such a screening effect allows to derive the maximal value of the magnetic field generated by these BPS magnetic vortices.

Relatore: Aldo Vera (Istituto Nazionale di Fisica Nucleare)

Aldo_Vera_QCD@work2024.pdf

16:30 The effect of electric and chiral magnetic conductivities on azimuthally fluctuating electromagnetic fields and observables in isobar collisions

We study the space-time evolution of electromagnetic fields along
with the azimuthal fluctuations of these fields and their correlation
with the initial matter geometry specified by the participant plane
in the presence of finite electric $\left(\sigma\right)$ and chiral
magnetic $\left(\sigma_{\chi}\right)$ conductivities in Ru+Ru and
Zr+Zr collisions at $\sqrt{s_{NN}}=200$ GeV. We observe the partially
asymmetric behavior of the spatial distributions of the electric and
magnetic fields in a conducting medium when compared to the Lienard-Wiechert
(L-W) solutions, and deceleration of the decay of the fields is observed
in both isobar collisions. While studying the correlation between
the magnetic field direction and the participant plane, we see the
sizeable suppression of the correlation in the presence of finite
conductivities when compared to the L-W case, reflecting the importance
of taking into account the medium properties such as conductivities
while calculating the magnetic field induced observable quantities.

Relatore: Irfan Siddique (University of Chinese Academy of Sciences)

Irfan_UCAS-QCD2024.pdf

17:00 → 17:30 Coffee

20:30 → 23:00 Workshop banquet

venerdì 21 giugno

09:00 → 10:50 Session 13

Coordinatore: Marco Pappagallo (INFN & University of Bari)

09:00 Insights in nuclei and hypernuclei production in Pb-Pb collisions with ALICE

Nuclear collisions at LHC energies are a unique opportunity to study hadronization mechanisms and the possible formation of exotic states. The excellent capability of the ALICE experiment to identify hadrons in a wide momentum range represents a great advantage in detecting hypernuclei, nuclear and exotic QCD bound states originating from a medium of deconfined QCD matter.
The data collected so far allow to search for such states in several collision systems and energies, thus providing a closer look at hadronization mechanisms and strong force interaction among baryons. In particular, the study of the properties of multi-baryon
states containing hyperons gives information on the hyperon-nucleon interactions that is complementary to correlation measurements.
Furthermore, the future upgrade of the ALICE experiment, namely ALICE3, will enlarge the physics reach of nuclei, hypernuclei and exotica measurements, allowing for the detection of heavy hadrons and exotica containing charm and beauty quarks.
This contribution presents the experimental results on nuclei and hypernuclei measured by the ALICE collaboration together with searches for exotic bound states. The perspectives for new measurements after the upgrade of the experiment will also be provided.

Relatore: Annalisa Mastroserio (Istituto Nazionale di Fisica Nucleare)

QCD@Work_AM.pdf

09:30 Revealing nucleus properties by exploring ultra-central symmetric heavy-ion collisions with scale-invariant initial states

Heavy-ion collision experiments are a valuable tool for studying nuclear properties. Accurately modeling entropy production at the initial collision time and subsequent collective evolution is crucial to connect the nuclear structure to heavy-ion measurements. In this talk, we argue that, based on experimental data, it is reasonable to assume scale-invariance at the initial state, meaning the produced entropy scales similarly to the thickness function of the nuclei participants. This implies that the observables receive a small contribution from the entropy production process and more from nuclear properties in ultracentral symmetric heavy-ion collision. With this conclusion, we employ cluster expansion decomposition to study the ellipticity fluctuation and introduce a formula for it. The formula is common for all scale-invariant initial state models and depends on the one-body and two-body density of the colliding nuclei. We show that this result is compatible with initial state models that obey scale invariance, such as TrENTo, with various values for p and initial state models based on CGC. We also explore its implications for studying nuclear properties in the isobar ratio measurements.

Relatore: Seyed Farid Taghavi

Taghavi-Slides-QCD@Work.pdf

09:50 Collision Integrals for First-Order Phase Transitions

A precise modelling of the dynamics of bubbles nucleated during first-order phase transitions in the early Universe is pivotal for a quantitative determination of various cosmic relics. The equation of motion of the bubble front is affected by the out-of-equilibrium distributions of particle species in the plasma which, in turn, are described by the corresponding Boltzmann equations. In this talk we present a solution to these equations that relies on a spectral decomposition that leverages the rotational properties of the collision integral within the Boltzmann equations. This novel approach allows for an efficient and robust computation of both the bubble speed and profile. We also refine our analysis by including the contributions from the electroweak gauge bosons. We find that their impact is dominated by the infrared modes and proves to be non-negligible, contrary to the naive expectations.

Relatore: Luigi Delle Rose (Istituto Nazionale di Fisica Nucleare)

QCDatWork2024_DelleRose.pdf

10:10 Recent developments in HQET

Relatore: Gil Paz (Wayne State University)

QCD@Work_2024_Paz.pdf

10:50 → 11:20 Coffee break

11:20 → 13:00 Session 14

Coordinatore: Pietro Colangelo (Istituto Nazionale di Fisica Nucleare)

11:20 Effects of atomic electron momentum distribution on resonant dark sector production

Experiments using positron beams impinging on fixed targets offer unique capabilities for probing new light dark particles feebly coupled to e^+ e^- pairs, that can be resonantly produced from positron annihilation on target atomic electrons. In this talk, I will discuss the impact of correctly accounting for the momentum distribution of the atomic electrons that shifts the center of mass energy of the annihilating e+e- pairs, and that must be taken into account in the determination of the number of signal events. After discussing how to reliably compute the cross section for the process, I will show how to obtain the bound electron momentum distribution for different target materials from theoretical computations or experimental data. Finally, I will apply these results to the search for the hypothetical X17 particle focusing on the expected reach of the PADME experiment.

Relatore: Giovanni Grilli di Cortona (Istituto Nazionale di Fisica Nucleare)

11:50 ATLAS measurements of Drell Yan processes

ATLAS has used the W and Z boson production processes to perform a range of precision measurements providing important tests of perturbative QCD and information about the parton distribution functions for quarks within the proton. This talk will present recent differential Z+heavy flavour jets results, measurements of the Drell-Yan cross section as a function of transverse momentum based on low pileup data, total W- and Z-boson cross section measurements at 13.6 TeV. Finally, the LHC pp collision data collected by the ATLAS experiment at sqrt(s)=7 TeV is revisited to measure the W boson mass and width.

Relatore: Fabio Anulli (Istituto Nazionale di Fisica Nucleare)

Anulli-QCDatWork.pdf

12:10 Challenges in top mass determination at LHC

The top quark mass is a fundamental parameter of the Standard Model, playing a crucial role in the electroweak precision tests and in any statement regarding the stability of the Universe. I discuss a recent top mass determination [see JHEP 06 (2023) 019, 2209.00583], based on a leptonic invariant mass, taking particular care about theoretical (Monte Carlo) uncertainties.

Relatore: Gennaro Corcella (INFN LNF)

toptrani.pdf

12:30 Physics at Future Accelerators

Relatore: Barbara Mele (Istituto Nazionale di Fisica Nucleare)

Trani QCDWork_Mele.pdf

13:00 → 13:05 Farewell