Seminarium Fizyki Wielkich Energii
2006/2007 | 2007/2008 | 2008/2009 | 2009/2010 | 2010/2011 | 2011/2012 | 2012/2013 | 2013/2014 | 2014/2015 | 2015/2016 | 2016/2017 | 2017/2018 | 2018/2019 | 2019/2020 | 2020/2021 | 2021/2022 | 2022/2023 | 2023/2024 | 2024/2025 | 2025/2026
2026-04-24 (Piątek)
Zapraszamy do sali B2.38, ul. Pasteura 5 o godzinie 11:30 
mgr Szymon Sławiński (IFD UW)Rare Bs0 decays at the CMS detector
Rare decays of b mesons can be used as a test of the Standard Model. The Large Hadron Collider at CERN, and the CMS detector provide a great experimental setup for searches for such rare decays. In this talk I will give an overview of the flagship analysis of the rare b decays group at CMS, the Bs to mu+ mu-. I will discuss the motivation behind the search, the analysis strategy, methods used and the results. Afterwards I will move on to the yet undiscovered rare decay channel of the Bs meson, the Bs to mu+ mu- gamma, that is the main topic of my PhD project. I will discuss the main challenges in the analysis and the progress made so far.
2026-04-17 (Piątek)
Zapraszamy do sali B2.38, ul. Pasteura 5 o godzinie 11:30
mgr Wiktor Matyszkiewicz, mgr Hagop Awedikian (IFD UW, NCBJ)Probing CP Structure in Higgs Boson Decays to Tau Lepton Pairs at CMS
The decay of the Higgs boson to tau lepton pairs provides a sensitive probe of its CP properties. This talk presents an overview of a CP analysis within the CMS Experiment, covering the workflow from tau lepton reconstruction to the extraction of CP-sensitive observables. The first part introduces the reconstruction of tau leptons in CMS, including their identification, decay mode classification, and the evaluation of scale factors. The second part outlines the main components of the CP analysis, including background estimation, modern approaches to neutrino reconstruction, and the construction of polarimetric observables sensitive to CP-violating effects. Together, these elements illustrate how advances in both object reconstruction and analysis methodology contribute to improved sensitivity to the Higgs boson’s CP structure.
2026-04-10 (Piątek)
Zapraszamy do sali B2.38, ul. Pasteura 5 o godzinie 11:30
dr Tobiasz Czopowicz (NCBJ)Status and plans of NA61/SHINE
The NA61/SHINE is a unique facility for measuring hadron production in collisions of various beams delivered by the Super Proton Synchrotron at CERN with a variety of stationary targets. For almost two decades it has explored the phase diagram of strongly interacting matter and performed reference measurements for neutrino and cosmic-rays experiments. I will try to present the key result obtained by the collaboration and discuss plans for the SHINE'y future.
2026-03-27 (Piątek)
Zapraszamy do sali B2.38, ul. Pasteura 5 o godzinie 11:30
prof. dr hab. Jacek Ciborowski (IFD UW)Fermat primes in flavour mixing and mass hierarchies
A Balmer-like empirical analysis of quark and neutrino mixing angles and of the charged-lepton mass hierarchy suggests a remarkable interplay between number theory and geometry, involving Fermat primes 5 and 17 (or equivalently the golden ratio in place of the former). The resulting pattern fixes two of the three a priori unknown parameters entering the (presently frequently exploited) Froggatt--Nielsen description of flavour hierarchies. This may provide useful guidance for further phenomenological studies (quark and neutrino masses) and possibly for the search for a more fundamental theory of flavour.
2026-03-20 (Piątek)
Zapraszamy do sali B2.38, ul. Pasteura 5 o godzinie 11:30
dr Haradhan Adhikary (IFD UW)Neutrino Flux Prediction and Uncertainties in T2K
Neutrino flux prediction and its associated uncertainties are of central importance for precision oscillation measurements in long-baseline experiments. In this talk, I will present the current neutrino flux prediction for the T2K experiment, obtained using hadron production measurements from NA61/SHINE at the CERN SPS on both thin and T2K replica targets.The methods employed in T2K to predict and constrain the neutrino flux will be described, including the use of external hadron production data and in-situ constraints from near-detector measurements. Finally, future plans within T2K to further improve flux prediction and uncertainty treatment will be outlined, together with a discussion of the broader community needs required to reduce flux-related uncertainties in support of next-generation precision neutrino oscillation experiments.
2026-03-06 (Piątek)
Zapraszamy do sali B2.38, ul. Pasteura 5 o godzinie 11:30
mgr Mariusz Girguś (IFD UW)Oscillatory pattern of atmospheric muon neutrino disappearance in Super-Kamiokande
Energia (E) neutrin atmosferycznych obserwowanych przez detektorze Super-Kamiokande zawiera się w przedziale od setek MeV do TeV, a przebyta przez nie droga (L) rozciąga się od 10 km do 13 000 km. Szeroki rozkład energii i przebytej drogi neutrin atmosferycznych skutkuje zakresem L/E obejmującym cztery rzędy wielkości i zawierającym liczne minima i maksima prawdopodobieństwa przeżycia neutrin mionowych. Z drugiej strony, rekonstrukcja E i L opiera się wyłącznie na właściwościach cząstek naładowanych powstałych w wyniku oddziaływań neutrin, co skutkuje niedoskonałą rozdzielczością L/E i rozmyciem kształtu oscylacyjnego dystrybucji L/E.Przedstawię wyniki najnowszej analizy oscylacji neutrin atmosferycznych, w której prawdopodobieństwa przeżycia neutrin mionowych jest badane bezpośrednio jako funkcja zrekonstruowanej długości lotu neutrina podzielonej przez zrekonstruowaną energię neutrina. Aby zachować oscylacyjny kształt i zminimalizować rozmycie rozkładu prawdopodobieństwa przeżycia, tylko podzbiór zdarzeń odpowiadający neutrinom atmosferycznym o dobrej rozdzielczości L/E jest wykorzystany do zbudowania dystrybucji zmiennej L/E.
Energy of atmospheric neutrinos observed in the Super-Kamiokande detector ranges from hundreds of MeV to a TeV scale, while the baseline spans from 10km to 13000km. The broad energy and baseline distributions of atmospheric neutrinos result in a range of L/E which spans four orders of magnitude and contains multiple minima and maxima of the muon neutrino survival probability. On the other hand, the reconstruction of neutrino energy and baseline is based solely on the properties of charged particles produced in neutrino interaction, resulting in a non-perfect resolution of L/E and smearing of the oscillatory pattern.I will present the results of the latest SK’s atmospheric neutrino oscillation analysis, in which the oscillatory pattern of muon neutrino survival probability is studied directly as a function of the reconstructed neutrino flight length divided by the reconstructed neutrino energy. In order to retain the oscillatory shape and minimize the smearing of the survival probability distribution, only a subset of atmospheric neutrino events, with an estimated high resolution of L/E, is binned according to the L/E scheme.
2026-02-27 (Piątek)
Zapraszamy do sali B2.38, ul. Pasteura 5 o godzinie 11:30
dr Alibordi Muhammad (IFD UW)Information-Geometric Approaches in High-Energy Physics
In this talk, I will explore how concepts from information geometry can provide new insights into complex phenomena in high-energy physics. I will present two illustrative examples: (1) a product manifold approach in machine learning that enhances classification performance for Vector Boson Fusion decays, and (2) a reformulation of CP violation from an information-geometric perspective. Finally, I will discuss potential applications of these techniques in the upcoming Phase-2 upgrade of the CMS experiment.
2026-01-23 (Piątek)
Zapraszamy do sali B2.38, ul. Pasteura 5 o godzinie 11:30
dr hab. Artur Kalinowski, prof. UW (IFD UW)Pomiar anomalnych momentów magnetycznych leptonów
Measurements of leptons anomalous magnetic moments
Przypomnę istotę anomalnego momentu magnetycznego punktowych, naładowanych, cząstek. Następnie przedstawię eksperymenty w których jest wykonywany pomiar tej wielkości dla leptonów ze wszystkich trzech generacji.
I will recall the essence of the anomalous magnetic moment of point-like, charged, particles. Then I will present the experiments which measure this quantity for all three lepton flavours.
2026-01-16 (Piątek)
Zapraszamy do sali B2.38, ul. Pasteura 5 o godzinie 11:30
prof. Anna Staśto (Penn State University)Inclusive charm photoproduction in ultraperipheral collisions at the LHC
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.
2026-01-09 (Piątek)
Zapraszamy do sali B2.38, ul. Pasteura 5 o godzinie 11:30
dr Małgorzata Kazana oraz dr Katarzyna Kowalik (NCBJ)Raport from the EPS-HEP conference
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)
2025-12-12 (Piątek)
Zapraszamy do sali B2.38, ul. Pasteura 5 o godzinie 11:30
dr hab. Sebastian Trojanowski (NCBJ)Far-forward physics at the LHC
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.
2025-11-28 (Piątek)
Zapraszamy do sali B2.38, ul. Pasteura 5 o godzinie 11:30
dr hab. Katarzyna Grzelak (IFD UW)DUNE - multi-purpose, liquid-argon, long-baseline neutrino experiment
DUNE is a long-baseline neutrino experiment, currently under construction in the United States. The neutrino beamline and near detectors will be located at Fermilab.Far detectors will be installed 1300 km away, more than a kilometer underground, at the Sanford Underground Research Laboratory in South Dakota. Their design is based on state-of-the-art Liquid Argon Time Projection Chamber technology.In the seminar, physics goals and the status of DUNE will be presented.
2025-11-21 (Piątek)
Zapraszamy do sali B2.38, ul. Pasteura 5 o godzinie 11:30
dr Davide Valsecchi (ETH Zurich)Machine Learning in CMS: new approaches for HEP challenges
Machine Learning plays an increasingly central role in the CMS experiment, supporting improvements across detector operations, event reconstruction, and physics analysis. This seminar provides an overview of how modern ML techniques are being applied within CMS, with examples ranging from enhanced detector-level reconstruction to likelihood-free inference methods and the use of normalizing flows for calibration tasks. These developments highlight the growing impact of machine learning applications for precise measurements and future discoveries at the LHC.
2025-11-07 (Piątek)
Zapraszamy do sali B2.38, ul. Pasteura 5 o godzinie 11:30
dr Tobiasz Czopowicz (NCBJ)Status and plans of NA61/SHINE
seminarium zostaje odwołane z przyczyn losowych
2025-10-17 (Piątek)
Zapraszamy do sali B2.38, ul. Pasteura 5 o godzinie 11:30
dr Tobiasz Czopowicz (NCBJ)Status and plans of NA61/SHINE
seminarium zostaje odwołane z przyczyn losowych
The seminar is canceled due to unforeseen circumstances
2025-10-10 (Piątek)
Zapraszamy do sali B2.38, ul. Pasteura 5 o godzinie 11:30
dr hab. Marcin Kuźniak, prof CAMK PAN (AstroCeNT)Search for dark matter within the Global Argon Dark Matter Collaboration programme
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.
2025-10-03 (Piątek)
Zapraszamy do sali B2.38, ul. Pasteura 5 o godzinie 11:30
dr hab. Grzegorz Grzelak, prof. dr hab. Aleksander Filip Żarnecki (IFD UW)LUXE and DRDcalo - calorimeter R&D for future experiments
The Faculty of Physics at the University of Warsaw is a member of theinternational LUXE (Laser Und XFEL Experiment) Collaboration. Theproject involves a groundbreaking experiment in the Eu.XFEL laboratoryin Hamburg. It aims to study the Quantum Electrodynamics (QED) in theregime of very strong fields. One of the key elements of the LUXEexperiment is a high-density electromagnetic calorimeter, ECAL-P,designed to precisely measure the energy and spectra of positronsproduced during collisions. The ECAL-P project is being developedwithin the framework of the CERN Detector R&D Collaboration onCalorimetry (DRD-calo).Members of the LUXE collaboration came to Warsaw in September to takepart in the collaboration meeting and the workshop of the ECAL-Pdetector group. The meeting in Warsaw was followed by the DRD-calocollaboration meeting in Ancona. We will report on the activities ofboth collaborations with particular focus on the Faculty of Physicscontribution.