Month: Maj 2022

SEMINARIUM FIZYKI WIELKICH ENERGII

Dnia 03 czerwca (piątek) o godzinie 10:15, w sali B2.38 odbędzie się

seminarium, na którym zostanie wygłoszony referat pt.:

„New description of neutrino flavour evolution in solar matter — oscillations or no oscillations?”

Referuje: Prof. dr hab. Jacek Ciborowski

Abstract:

During the seminar I will present new analysis performed with ZEUS data on exclusive Assuming that the interacting neutrino and the solar matter can be treated as an open quantum system we formulate a formalism of neutrino state evolution according to a quasilinear extension of the von Neumann equation. We broaden the classical linear Wolfenstein formalism (MSW effect) by means of reinterpreting the results in terms of the quantities appropriate for the quasilinear approach. We show that the dynamics of the neutrino evolution („flavour conversion”) is effectively governed by the distance of the evolving system to the structural instability point of the evolution equation. We obtain similar predictions for the averaged neutrino survival probability measured on Earth in both approaches, differing inside the Sun where the quasilinear evolution predicts a suppression of oscillations. A nonzero mean energy transfer between the neutrino and the Sun supports the initial assumption. We also discuss the speed of the state evolution in both approaches. Ways to test on Earth the quasilinear hypothesis will be mentioned.

Serdecznie zapraszamy

dr hab. Katarzyna Grzelak
prof. dr hab. Jan Królikowski
prof. dr hab. Aleksander Filip Żarnecki

SEMINARIUM FIZYKI WIELKICH ENERGII

Dnia 27 maja (piątek) o godzinie 10:15, w sali B2.38 odbędzie się

seminarium, na którym zostanie wygłoszony referat pt.:

„Measurement of the cross-section ratio σ(ψ(2S)) / σ(J/ψ(1S)) in exclusive photoproduction at HERA.”

Referuje: dr hab. Grzegorz Grzelak

Abstract:

During the seminar I will present new analysis performed with ZEUS data on exclusive vector meson photoproduction – measurement of the cross section ratio of two charmonia states: ψ(2S) and J/ψ(1S). The analysis was performed using muonic decay channels of the investigated vector mesons.

The ratio of their production cross sections has been measured as a function of W (photon–proton centre-of-mass energy) and |t| (squared four-momentum transfer at the proton vertex) and compared to previous data in photoproduction and deep inelastic scattering and with predictions of QCD-inspired models of exclusive vector-meson production.

Serdecznie zapraszamy

dr hab. Katarzyna Grzelak
prof. dr hab. Jan Królikowski
prof. dr hab. Aleksander Filip Żarnecki

SEMINARIUM FIZYKI WIELKICH ENERGII

Dnia 20 maja (piątek) o godzinie 10:15, w sali B2.38 odbędzie się

seminarium, na którym zostanie wygłoszony referat pt.:

„Looking forward to new physics and neutrinos at the LHC and beyond.”

Referuje: dr Sebastian Trojanowski (NCBJ)

Abstract:

The search for new physics and studying the properties of the Standard Model (SM) neutrinos are among the main frontiers in contemporary particle physics. In particular, new physics searches at the Large Hadron Collider (LHC) have traditionally been performed in the high-pT region. If new particles are light and weakly-coupled, however, this focus may be misguided: light particles are typically highly concentrated within a few mrad of the beam line. This opens up a novel direction in the LHC searches focusing on sub-GeV beyond the SM species and neutrino measurements, which will be initiated by the FASER experiment during Run 3. In the talk, we will discuss the prospects of these and other related efforts that can extend towards the High-Luminosity phase of the LHC in the recently proposed Forward Physics Facility (FPF).

Serdecznie zapraszamy

dr hab. Katarzyna Grzelak
prof. dr hab. Jan Królikowski
prof. dr hab. Aleksander Filip Żarnecki

SEMINARIUM FIZYKI WIELKICH ENERGII

Dnia 13 maja (piątek) o godzinie 10:15, w sali B2.38 odbędzie się

seminarium, na którym zostanie wygłoszony referat pt.:

„DIS landscape 2022 – a personal view”

Referuje: prof. dr hab. Barbara Badełek (IFD UW)

Abstract:

For the last 50+ years the Deep Inelastic Scattering is a source of our knowledge concerning properties of building blocks of nearby matter:

nucleons and nuclei. DIS has supplied a wealth of astonishing discoveries and induced a development of the theory of strong interactions, the (perturbative) Quantum ChromoDynamics.

A panorama of contemporary knowledge and problems concerning the free- and bound nucleon structure will be given and directions of future investigations and available tools will be presented.

Serdecznie zapraszamy

dr hab. Katarzyna Grzelak
prof. dr hab. Jan Królikowski
prof. dr hab. Aleksander Filip Żarnecki