Thesis topics in Physics (for October 2023)

Application deadline: May 15th.

  1. Probing CP structure of the Yukawa coupling of the Higgs boson and tau leptons
    • Supervisor: Dr hab. M. Bluj, prof. NCBJ
    • Description: The discovery of the Higgs boson with mass of about 125 GeV and properties consistent with the predictions of the Standard Model (SM) of fundamental interactions confirmed the mechanism of mass generation by spontaneous symmetry breaking built into the model. However, despite its success, the SM is unable to solve fundamental questions of Nature, such as the question of the origin of the matter- antimatter asymmetry in the Universe or the nature of dark matter.
      Extensions of the Higgs sector of the SM may provide new sources of combined charge-parity (CP) symmetry violation, which is one of the necessary conditions for the emergence of the matter-antimatter asymmetry, as well as candidates for dark matter particles. Such extensions can modify the Yukawa couplings of the Higgs boson and fermions by adding a new CP-odd component to the CP-even one predicted by the SM. If such a CP-odd component would be discovered, it would indicate a physics beyond the SM. On the other hand, the lack of such an observation will allow to impose constraints on possible extensions of the SM
      The aim of this PhD project is to study the CP structure of the tau Yukawa coupling, i.e. coupling between the Higgs boson and tau leptons. This measurement will be performed by analysing the correlation between the spins of the tau leptons produced in the Higgs boson decays using data collected by the CMS detector at the LHC in 2022-2025 (LHC Run-3).
    • Funding: NCBJ Fellowship
  2. Structural Characterization of Radiation Effects in Oxide Materials
    • Supervisor: Prof. Frederico Garrido
    • Auxiliary Supervisor: Dr Cyprian Mieszczyński
    • Description: You are going to be involved in the multilateral project in collaboration with Paris-Saclay University regarding structural investigations of radiation effects in oxide materials with the possible use for the energy industry. Both for renewable sources (semiconductors – optoelectronic devices) and nuclear energy (nuclear fuels). The Ion Beam Analysis techniques (RBS, RBS/c, PIXE) will be mainly used for structural characterization. As a comparative method, the Raman and High-resolution XRD analysis will be used. The Monte Carlo and Molecular Dynamics simulations performed for quantitative analysis of material defects will also be an important element of the studies. If you join us, you will have a great opportunity to perform experimental investigations in many foreign research centers and present results at international conferences.
      We are looking for candidates with basic knowledge of structural and simulation techniques (preferably basic knowledge of programming in C ++) and communicative skills in English.
    • Funding: NCN Fellowship
  3. Study of defects and Rare Earth dopants into Ga2o3
    • Supervisor: Prof. dr hab. Elżbieta Guziewicz
    • Auxiliary Supervisor: Dr Renata Ratajczak
    • Description: Gallium Oxide (Ga2O3) is one of the currently most popular materials, that have attracted great attention from the scientific community. According to our project plan the properties of this material are going to be modified by doping with Rare Earth (RE) using ion implantation. Such Ga2O3:RE systems are extremely important for future applications in optoelectronics .
      In your work, you will deal with the structural, electrical and optical research of a range of physical phenomena that are related to the ion implantation process, as well as with designing the parameters to obtain efficient monochromatic light source emitters based on this material. Being involved in the growth processes of Ga2O3 using Atomic Layer Deposition (ALD) method will also be an important element of your studies.
      For the structural characterization of RE implanted Ga2O3, both bulk single crystals and ALD layers, mainly the RBS/c analytical technique will be used, as well as comparative methods like Raman and XRD analysis. You are going to be involved in the PL and Hall effect measurements too.
      The majority of these investigations will be realized outside NCBJ, mainly at the Institute of Physics PAS, Warsaw, Poland. If you join us, you will also have a great opportunity to perform experimental investigations in many foreign research centers as well as present results at international conferences. We are looking for candidates with basic knowledge of structural or optical studies of monocrystals. Experience in layer growing with the ALD technique will be well-received.
    • Funding: NCN Fellowship
  4. Half-life measurement techniques. Investigation of the properties of long-lived isomers
    • Supervisor: Dr hab. Michał Gierlik, prof. NCBJ
    • Auxiliary Supervisor: Dr Łukasz Janiak
    • Description: We investigate production methods and properties of isomers that may have any potential as a medium for energy storage. Our daily efforts are concentrated on isomer production techniques, development and improvements to the experimental set-up, and last but not least, data analysis. There is a position in our team for a student with programming skills and the understanding of measurement and error analysis.
    • Funding: NCBJ Fellowship
  5. Prediction of the cross-sections for the synthesis of super heavy nuclei
    • Supervisor: Dr hab. Michał Kowal, prof. NCBJ
    • Description: The Ph.D. thesis will aim to assess the possibility of producing superheavy nuclei in future experiments and understanding the mechanisms governing the synthesis reactions. Particular emphasis will be placed on understanding and analyzing the hindrance phenomenon in the fusion process. For this purpose, we will use a dissipative dynamic based on stochastic equations. We will apply the diffusion equations on multidimensional energy surfaces with total angular momentum taken into account. Additionally, we will examine the quantum shell effect on the probability of formation and survival of a newly created superheavy nucleus.
    • Funding: NCBJ Fellowship
  6. Determination of the hadronic vacuum polarization contribution to the muon anomalous magnetic moment
    • Co-Supervisor: Prof. dr hab. Andrzej Kupść
    • Co-Supervisor: Prof. dr hab. Wojciech Wiślicki
    • Description: The muon anomalous magnetic moment g-2, where g is the gyromagnetic ratio of the muon, is one of the exceptional cases in particle physics at low energy where a significant discrepancy between measurement and Standard Model (SM) prediction has persisted for more than 20 years. This discrepancy, now reaching 4.2 sigma, could be a compelling evidence of physics beyond the SM. In view of the new experimental efforts under way at Fermilab (USA) and J-PARC (Japan) to improve the g-2 accuracy, a confirmation of its SM prediction is now mandatory. Its hadronic contributions are under particular scrutiny, as they induce the main uncertainty of the SM prediction. The KLOE experiment at the phi-factory DAphNE in Frascati (near Rome) is the first to have employed Initial State Radiation to precisely determine the e+e- –> pi+pi-gamma cross section below 1 GeV. This PhD project is focused on the analysis of the full KLOE data sample and should improve by a factor 2 current accuracy on contribution to g-2 from hadronic vacuum polarization. It will place a significant constraint on the SM prediction to the muon g-2. The project also requires involvement in development of Monte Carlo generator for this process. A successful candidate is expected to work on the analysis of data and simulation software and will be assisted by experienced senior colleagues.
    • Funding: NCBJ Fellowship
  7. Low surface brightness galaxies in the LSST era
    • Supervisor: Dr hab. Katarzyna Małek, prof. NCBJ
    • Auxiliary Supervisor: Dr Junais
    • Description: The upcoming Legacy Survey of Space and Time (LSST) will be the benchmark for the next decade, providing unprecedented depth and quality optical data on millions of galaxies, including low and high surface brightness galaxies, LSBs and HSBs, respectively. This PhD project focuses on the identification and analysis of LSBs, which are very diffuse and fainter than the typical night sky, using the LSST data. The PhD student will investigate intermediate galaxies between LSBs and HSBs to understand if there is an intrinsic separation or continuity between the two populations.
      In the framework of this project, the PhD candidate will perform morphological analysis on these galaxies to estimate their properties such as size, surface brightness, and concentration. Several widely used tools like Galfit, Photutils, Autoprof, and machine learning techniques will be used to compare and evaluate the robustness of different tools for optimal morphological estimation of faint galaxies. The student will also carry out a multi-wavelength analysis of these galaxies by compiling ancillary data from the literature (e.g., GALEX, Spitzer, JWST, Herschel). The CIGALE tool will be used to perform Spectral Energy Distribution (SED) fitting techniques to estimate the stellar mass, star-formation rate, and dust attenuation of the galaxies.
      Our team is an active member of the LSST collaboration with access to early data releases that will be available at the beginning of the 2024 year. We also have experts in the field of LSBs, galaxy morphology, as well as SED fitting. Therefore, this PhD project offers a unique opportunity for the student to gain expertise in all these aspects. The results of this research will provide essential insights into the nature of very faint galaxies and their role in galaxy formation and evolution scenarios.
    • Funding: NCBJ Fellowship