Category: Uncategorized

Dnia 16 stycznia (piątek) o godzinie 11:30, w sali B2.38 odbędzie się seminarium, na którym zostanie wygłoszony referat pt.:

„Inclusive charm photoproduction in ultraperipheral collisions at the LHC”

Referuje: prof. Anna Staśto (Penn State University)

Ultraperipheral collisions (UPCs) of nuclei at high energies offer unique opportunity to explore the nuclear structure in a clean environment. UPCs occur when two nuclei scatter at impact parameters that exceed the sum of nuclear radii. The UPCs lead to large photonuclear cross sections.  In UPC processes involving jets or heavy quarks, large scale allows for perturbative description of the process, and thus such processes can serve as good probes of the nuclear structure. We present the calculation of the  inclusive D0 production cross section in UPC PbPb collisions at the LHC using the Generalized photon-nucleus FONLL framework. In this approach the heavy quark production is computed using the FONLL framework developed previously by Cacciari-Frixione-Nason for ep collisions,  and includes additional electromagnetic corrections to describe the photoproduction cross section in UPC heavy ion collisions. The calculations are validated against the D* photoproduction cross section from HERA. The predictions for D0 cross section as a function of rapidity and transverse momentum of the D0 meson are presented and compared to the preliminary results from UPC collisions measured by CMS. The sensitivity of the results is studied, when different choices of parton distribution functions and fragmentation functions are made, as well as a function of variation in renormalization and factorization scale dependence.

Serdecznie zapraszamy

dr hab. Katarzyna Grzelak

prof. dr hab. Aleksander Filip Żarnecki

Dnia 9 stycznia (piątek) o godzinie 11:30, w sali B2.38 odbędzie się seminarium, na którym zostanie wygłoszony referat pt.:

„Raport from the EPS-HEP conference”

Referują: dr Małgorzata Kazana (NCBJ)

dr Katarzyna Kowalik  (NCBJ)

The European Physical Society Conference on High Energy Physics (EPS-HEP) is one of the major international conferences organized every second year. The latest edition was hosted in Marseille, France in the summer of 2025. The conference highlighted the latest breakthroughs and developments across a broad range of topics, including high energy and particle physics, astroparticle physics, neutrino physics, and related disciplines.

During the seminar we will review two topics: LHC physics (M.Kazana) and neutrino physics (K.Kowalik)

Serdecznie zapraszamy

dr hab. Katarzyna Grzelak

prof. dr hab. Aleksander Filip Żarnecki

SEMINARIUM FIZYKI WIELKICH ENERGII

Dnia 12 grudnia (piątek) o godzinie 11:30, w sali B2.38 odbędzie się seminarium, na którym zostanie wygłoszony referat pt.:

„Far-forward physics at the LHC”

Referuje: dr hab. Sebastian Trojanowski (NCBJ)

The launch of the LHC Run 3 data-taking period marked the advent of the collider neutrino physics program and far-forward BSM studies via the dedicated FASER and SND@LHC experiments. The neutrino program aims to bridge gaps in precision neutrino measurements. It also serves as a novel window to test hadronic interactions at high energies and large pseudorapidities, which generate forward neutrinos at the LHC.

The new physics program is dedicated to probing BSM scenarios connected to theoretical thermal dark matter targets. In this talk, we will summarize ongoing measurements, outline future plans, and highlight selected specific applications of this experimental program.

Serdecznie zapraszamy

dr hab. Katarzyna Grzelak

prof. dr hab. Aleksander Filip Żarnecki

SEMINARIUM FIZYKI WIELKICH ENERGII

Dnia 10 października (piątek) o godzinie 11:30, w sali B2.38 odbędzie się seminarium, na którym zostanie wygłoszony referat pt.:

„Search for dark matter within the Global Argon Dark Matter Collaboration programme”

Referuje: dr hab. Marcin Kuźniak, prof CAMK PAN (AstroCeNT)

The nature of dark matter is one of the most important questions of contemporary physics. Observational evidence supports the existence of dark matter, which constitutes approximately 27% of the Universe mass-energy balance. Its exact nature remains unknown, however there are some indications that it could be a new type of particles beyond the Standard Model, such as the weakly interacting massive particles (WIMP).

The direct search for interactions of WIMPs with ordinary matter is carried out with large underground detectors, with currently the most promising detection technology based on the use of a large scintillating mass of liquid argon or xenon as the detector medium. Efficient collection and detection of scintillation light from multi-tonne detectors poses challenges and motivates dedicated R&D on optical materials, including wavelength shifters, as well as on photosensors.

Such work at AstroCeNT, either in the context of the Global Argon Dark Matter Collaboration, or general R&D applicable also to neutrino detectors, will be presented, together with a brief overview of the field.

Serdecznie zapraszamy

dr hab. Katarzyna Grzelak

prof. dr hab. Aleksander Filip Żarnecki

SEMINARIUM FIZYKI WIELKICH ENERGII

Dnia 3 października (piątek) o godzinie 11:30, w sali B2.38 odbędzie się seminarium, na którym zostanie wygłoszony referat pt.:

„LUXE and DRDcalo – calorimeter R&D for future experiments”

Referują: dr hab. Grzegorz Grzelak
          prof. dr hab. Aleksander Filip Żarnecki

The Faculty of Physics at the University of Warsaw is a member of the
international LUXE (Laser Und XFEL Experiment) Collaboration.  The
project involves a groundbreaking experiment in the Eu.XFEL laboratory
in Hamburg. It aims to study the Quantum Electrodynamics (QED) in the
regime of very strong fields. One of the key elements of the LUXE
experiment is a high-density electromagnetic calorimeter, ECAL-P,
designed to precisely measure the energy and spectra of positrons
produced during collisions. The ECAL-P project is being developed
within the framework of the CERN Detector R&D Collaboration on
Calorimetry (DRD-calo).

Members of the LUXE collaboration came to Warsaw in September to take
part in the collaboration meeting and the workshop of the ECAL-P
detector group. The meeting in Warsaw was followed by the DRD-calo
collaboration meeting in Ancona. We will report on the activities of
both collaborations with particular focus on the Faculty of Physics
contribution.

Serdecznie zapraszamy

dr hab. Katarzyna Grzelak

prof. dr hab. Aleksander Filip Żarnecki

SEMINARIUM FIZYKI WIELKICH ENERGII

Dnia 8 lipca (wtorek) o godzinie 10:00, w sali B2.38 odbędzie się seminarium, na którym zostanie wygłoszony referat pt.:

„Search for CP Violation in H→ττ Decays at CMS”

Referuje: Alexei Raspiateza (DESY)

During the seminar results from the analysis of Run 2 data collected by the CMS experiment will be presented, as well as anticipated improvements in the analysis sensitivity with the  polarimetric vector approach assisted by the FastMTT algorithm developed by the Warsaw group.

Serdecznie zapraszamy

dr hab. Katarzyna Grzelak

prof. dr hab. Aleksander Filip Żarnecki

SEMINARIUM FIZYKI WIELKICH ENERGII

Dnia 13 czerwca (piątek) o godzinie 11:30, w sali B2.38 odbędzie się seminarium, na którym zostanie wygłoszony referat pt.:

„Transverse-Spin Dependent Azimuthal Asymmetries in COMPASS Drell-Yan data: Toward a 3D Picture of the Nucleon”

Referuje: mgr Małgorzata Niemiec (IFD UW)

Understanding the internal structure of the nucleon is a central challenge in hadron physics. Traditional QCD formulation neglects partons’ transverse momentum, but a more complete, 3D nucleon tomography emerges through Transverse Momentum Dependent Parton Distribution Functions (TMD PDFs). I will focus on transverse-spin dependent azimuthal asymmetries in the Drell–Yan process from COMPASS experiment, using a novel weighting method based on the transverse momentum of the dimuon pair. This approach allows extraction of particular moments of TMD PDFs, providing new insights into the nucleon’s transverse structure and parton dynamics. These results represent a key study that will be further developed in future experiments, including LHCspin and the Electron-Ion Collider.

Serdecznie zapraszamy

dr hab. Katarzyna Grzelak

prof. dr hab. Aleksander Filip Żarnecki

SEMINARIUM FIZYKI WIELKICH ENERGII

Dnia 30 maja (piątek) o godzinie 11:30, w sali B2.38 odbędzie się seminarium, na którym zostanie wygłoszony referat pt.:

„Long-Lived Particle Searches at a Future Higgs Factory with the ILD experiment”

Referuje: mgr Jan Klamka (IFD UW)

Future e+e– colliders provide a unique opportunity for long-lived particle (LLP) searches. I will present a full simulation study of LLP searches using the International Large Detector (ILD), a detector concept for a future Higgs factory, with a gaseous time projection chamber as its main tracking device. Signatures of displaced vertices and kinked tracks are explored. Challenging final states involving both very soft displaced tracks and boosted, nearly collinear tracks have been studied. Backgrounds from beam-induced interactions and other Standard Model processes are considered. Expected exclusion limits will be presented for a model-independent analysis, as well as for Higgs boson decays to LLPs, for a range of LLP lifetimes.

Serdecznie zapraszamy

dr hab. Katarzyna Grzelak

prof. dr hab. Aleksander Filip Żarnecki

Dnia 16 maja (piątek) o godzinie 11:30, w sali B2.38 odbędzie się seminarium, na którym zostanie wygłoszony referat pt.:

„Recent  heavy flavour results from CMS”

Referuje: dr hab. Marcin Konecki, prof. UW (IFD UW)

The CMS experiment has delivered numerous significant measurements using data from LHC Run-2 and the ongoing Run-3. This report explains key components of the CMS detector relevant to heavy flavour physics. The short introduction to CP violation in Bs → J/ψϕ(1020) is given, followed by the recent CMS results, confirming the CP violation in this channel. The search for CP violation in Ds → Ks0 Ks0 channel is presented. In addition the most important information on selected recent CMS heavy flavour physics results is highlighted. It includes: measurement of Bs → J/ψKS effective lifetime, test of lepton flavour universality with RJ/ψ and search for rare decays in D0 → µ+ µ− . Finally the CMS measurements of B/Bs → µ+ µ− are reminded.

Serdecznie zapraszamy

dr hab. Katarzyna Grzelak

prof. dr hab. Aleksander Filip Żarnecki

SEMINARIUM FIZYKI WIELKICH ENERGII

Dnia 25 kwietnia (piątek) o godzinie 11:30, w sali B2.38 odbędzie się seminarium, na którym zostanie wygłoszony referat pt.:

„Vector Boson Fusion at the Muon Collider: electroweak factorisation and PDFs”

Referuje: Krzysztof Mękała (University of Warsaw/DESY)

As the European Strategy for Particle Physics undergoes its latest update, the scientific community is shaping the direction of the field for the decades to come. Central to this process is the decision on CERN’s next major collider initiative. Among the proposed options is a high-energy muon collider, aiming to probe the TeV scale, which would significantly enhance our understanding of the Standard Model, with a particular focus on electroweak interactions at previously unexplored energies. A key area of interest lies in vector-boson fusion, which is expected to dominate the high-energy landscape of many fundamental processes.

In my talk, I will outline the primary physics objectives of the Muon Collider project, with an emphasis on the role of vector-boson fusion. I will introduce the concepts of the collinear approximation and electroweak factorisation, and discuss the motivation behind revisiting this framework in the context of a future collider facility. Finally, I will present the emerging idea of electroweak Parton Distribution Functions and review their relevance in this setting.

Serdecznie zapraszamy

dr hab. Katarzyna Grzelak

prof. dr hab. Aleksander Filip Żarnecki