Calendar

Apr
11
Lun
Properties of heavy mesons in a hot medium within a thermal effective theory @ Aula 602 e online
Apr 11@11:00 am–12:00 pm

Seminario di fenomenologia INFN/DIFI – Dr. Gloria Montaña (Barcelona University)

The quark-⁠gluon plasma (QGP) is expected to be produced with heavy-⁠ion collisions at RHIC and LHC at very high temperatures and vanishing baryon densities. Charmed mesons are a promising probe of this hot state of strongly interacting matter, as charm quarks are produced in the early stages of the collision and experience the whole evolution of the system. In order to describe the experimental data, a proper theoretical understanding of the propagation of charmed mesons in a hot medium is mandatory. While lattice QCD is becoming an increasingly important tool in this regime, we employ a complementary theoretical methodology that allows us to approach the QGP transition from the
hadronic phase. In particular, we have recently studied the thermal modification of open-⁠charm mesons in a hot mesonic medium by applying an effective field theory based on chiral and heavy-⁠quark spin-⁠flavour symmetries [1,2]. In this approach, the in-⁠ medium unitarized amplitudes of the scattering of the heavy mesons off the light mesons and the self-⁠energies of the heavy mesons are calculated
self-⁠consistently. I will summarize our findings regarding the in-⁠medium properties (masses and decay widths) of the ground-⁠state heavy mesons, as well as those of the excited mesonic states that are
dynamically generated in our heavy-⁠light molecular model, such as the D_0^*(2300) and the D_{s0}^*(2317). Besides, I will report on our results for the open-⁠charm Euclidean correlators and their comparison with those obtained with lattice QCD [3]. Finally, I will discuss the effect on the heavy-⁠flavour transport coefficients, like the drag and transport coefficients, of the scattering of the heavy mesons with the hot medium [4].

[1] G. Montana, A. Ramos, L. Tolos and J. M. Torres-⁠Rincon, Phys.
Lett. B 806 (2020), 135464.
[2] G. Montana, A. Ramos, L. Tolos and J. M. Torres-⁠Rincon, Phys.
Rev. D 102 (2020) 9, 096020.
[3] G. Montana, O. Kaczmarek, L. Tolos and A. Ramos, Eur. Phys. J. A
56 (2020) 11, 294
[4] J. M. Torres-⁠Rincon, G. Montana, A. Ramos and L. Tolos,
Phys.Rev.C 105 (2022) 2, 025203
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Per partecipare in presenza, prenotarsi seguendo il link
https://docs.google.com/document/d/1uaw5DHG0VykTHraDiAqYjbLFXsrOIXaftj_n04sj4PE/edit?usp=sharing
oppure per partecipare su Zoom, collegarsi al meeting
Topic: Theory and Pheno seminars
https://infn-it.zoom.us/j/8573185271
Meeting ID: 857 318 5271

Apr
21
Gio
Theory of pinned viscoelastic hydrodynamics @ on-line e Aula 601
Apr 21@11:00 am–12:00 pm

Seminario di Fisica Teorica INFN/DIFI – Dr Akash Jain (Amsterdam U.)

Symmetries are a powerful organizational tool in physics that can be used to construct effective theories for physical systems without a detailed understanding of their microscopic constituents. The symmetries under consideration need not be fundamental. Even the knowledge about approximate effective symmetries of the system under consideration can go a long way in constructing an effective description. In this talk, we will construct an effective theory for pinned viscoelastic crystals by exploiting approximate translational symmetry. We will analyze the constraints from the second law of thermodynamics and use these to derive the damping-attenuation relation in pinned crystals. In the process, we will also unravel various new transport coefficients that show up in the stress and energy constitutive relations of these systems and probe their physical significance. The talk will be based on https://arxiv.org/abs/2112.1437
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Per partecipare in presenza, prenotarsi seguendo il link
https://docs.google.com/document/d/1uaw5DHG0VykTHraDiAqYjbLFXsrOIXaftj_n04sj4PE/edit?usp=sharing
oppure per partecipare su Zoom, collegarsi al meeting
Topic: Theory and Pheno seminars
https://infn-it.zoom.us/j/8573185271
Meeting ID: 857 318 5271

Apr
28
Gio
Quark-Gluon Plasma at the LHC: studying the extreme state of QCD with heavy-ion collisions @ on-line
Apr 28@11:00 am–12:00 pm

Colloquium INFN/DIFI – Andrea Dainese (INFN Padova)

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Per partecipare in presenza, prenotarsi seguendo il link
https://docs.google.com/document/d/1uaw5DHG0VykTHraDiAqYjbLFXsrOIXaftj_n04sj4PE/edit?usp=sharing
oppure per partecipare su Zoom, collegarsi al meeting
Topic: Theory and Pheno seminars
https://infn-it.zoom.us/j/8573185271
Meeting ID: 857 318 5271

Mag
5
Gio
Collinear functions for QCD resummations @ A601 e online
Mag 5@11:00 am–12:00 pm

Seminario di Fisica Teorica – Prasanna Dhani (INFN Genova)
Singular factors originating from the QCD factorisation of scattering amplitudes in soft and collinear limits play a prominent role in both organising and computing high-order perturbative contributions to hard-scattering cross sections. In this talk, I will report on recent work done in collaboration with Stefano Catani. We start from the factorisation structure of scattering amplitudes in the collinear limit, and we introduce collinear functions that have a process-independent structure. These collinear functions, which are defined at the fully-differential level, can then be integrated over the appropriate observable-dependent phase space to compute logarithmically-enhanced contributions to the corresponding observable. For transverse-momentum dependent observables, we show how the collinear functions can be defined without introducing what is known as rapidity divergences in the literature. We present the results of explicit computations of the collinear functions up to next-to-next-to-leading order.
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Per partecipare in presenza, prenotarsi seguendo il link
https://docs.google.com/document/d/1uaw5DHG0VykTHraDiAqYjbLFXsrOIXaftj_n04sj4PE/edit?usp=sharing
oppure per partecipare su Zoom, collegarsi al meeting
Topic: Theory and Pheno seminars
https://infn-it.zoom.us/j/8573185271
Meeting ID: 857 318 5271

Mag
12
Gio
MIxed QCD-electroweak corrections to Drell-Yan production @ Aula 601 e online
Mag 12@11:00 am–12:00 pm

Seminario di Fenomenologia – Dr. Raoul Röntsch (Universitá di Milano)

Drell-Yan production is one of the keystone processes at hadron colliders, relevant for a multitude of analyses from precision measurements of the Standard Model parameters to searches for New Physics. As such, it is important to obtain highly precise theoretical predictions to compare with data. I will discuss the computation of mixed QCD-EW corrections to onshell vector boson production and highlight their impact on the measurement of the mass of the W boson, where the target precision is around 0.1 permille. I will then discuss the calculation of mixed QCD-EW corrections to massless dilepton production, and present results focusing on intermediate to high invariant mass regions.
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Per partecipare in presenza, prenotarsi seguendo il link
https://docs.google.com/document/d/1uaw5DHG0VykTHraDiAqYjbLFXsrOIXaftj_n04sj4PE/edit?usp=sharing
oppure per partecipare su Zoom, collegarsi al meeting
Topic: Theory and Pheno seminars
https://infn-it.zoom.us/j/8573185271
Meeting ID: 857 318 5271

Mag
26
Gio
New avenues of QFT in curved spacetime @ Aula 603 e online
Mag 26@2:30 pm–3:30 pm

Seminario di Fisica teorica INFN/DIFI – Vincenzo Vitagliano (Universitá di Genova)

Spontaneous symmetry breaking is a transversal concept in modern physics, being pivotal for our understanding of mass generation in particle physics, topological defects formation in cosmology, and the appearance of condensed phases of matter. I will discuss some recent results about the way symmetry breaking occurs for systems embedded in a curved background, when curvature acts as an effective mass that, depending on the sign, enhances or suppresses the mechanism responsible for phase transitions. I will then move to a general discussion about the ground state of nonlinear field theories, commenting on the substantial changes in the structure of the quantum vacuum occurring even for the simplest choice of boundary conditions. Not only this leads to nontrivial modulation of the Casimir force as a function of external conditions, but it also regulates the behaviour at small vs large scales.
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Per partecipare in presenza, prenotarsi seguendo il link
https://docs.google.com/document/d/1uaw5DHG0VykTHraDiAqYjbLFXsrOIXaftj_n04sj4PE/edit?usp=sharing
oppure per partecipare su Zoom, collegarsi al meeting
Topic: Theory and Pheno seminars
https://infn-it.zoom.us/j/8573185271
Meeting ID: 857 318 5271

Ott
6
Gio
Gravitational multipoles beyond, Bogdan Ganchev (Saclay University) @ 602 e online
Ott 6@11:00 am–12:00 pm

(Seminario di Fisica Teorica)
In this talk I consider gravitational mulipoles in 4D theories beyond pure Einstein gravity. For the Kerr black hole, the mutlipole moments are uniquely determined by the first mass and current multipoles, but this is not necessarily true beyond classical gravity, in string theory for example. We will look at the effects of higher-derivative corrections to the Kerr mutlipoles from an EFT point of view and discuss their viability as probes of corrections to the Kerr black hole. We will also discuss whether the richer structure of multipole moments in string theory, as compared to that of the Kerr black hole, can be used to pose constraints on corrections to General Relativity coming from string theory.

Per connettersi a zoom

Topic: Theory and Pheno seminars

https://infn-it.zoom.us/j/8573185271
Meeting ID: 857 318 5271

Ott
13
Gio
Analytic bootstrap of mixed correlators in the O(n) CFT (Francesco Bertucci, Università di Pisa @ Aula 602 e online
Ott 13@11:00 am–12:00 pm

Conformal field theories have two main characteristics. First, they are important in the study of critical phenomena. Second, their rigid structure makes them suitable to test theoretical challenges and obtain general results. In this talk, I will describe some of their general features and see how physical data can be extracted using powerful theoretical tools. Specifically, I will focus on the study of the O(n) CFT in less than four dimensions, trying to systematize the study of four-point correlators. I will explain how to use the Lorentzian inversion formula to extract physical data in perturbation theory and discuss some interesting features and technical details which arise in the process.

Per connettersi a zoom

Topic: Theory and Pheno seminars

https://infn-it.zoom.us/j/8573185271
Meeting ID: 857 318 5271