Physics thesis topics

  1. From inclusive to exclusive physics in High-Energy Collisions 
    • Supervisor: prof. dr hab. Lech Szymanowski 
    • Auxiliary supervisor: dr Tolga Altinoluk 
    • Description: Our understanding of protons and neutrons, or nucleons—the building blocks of atomic nuclei—has advanced dramatically, both theoretically and experimentally, in the past half century. It is known that nucleons are made of fractionally charged “valence” quarks, as well as dynamically produced quark-antiquark pairs, all bound together by gluons, the carrier of the strong force. A central goal of modern nuclear physics is to understand the structure of the proton and neutron directly from the dynamics of their quarks and gluons governed by the theory of their interactions, quantum chromodynamics. The designed the Electron Ion Collider (EIC)  is the instrument that can answer many of these fundamental questions. The topics of this PhD project focus on theoretical investigation of some processes which are phenomenologically important for EIC physics studies. The special emphasis will be put on the studies of the diffractive production of light and of heavy particles described within two different dynamical approaches: the QCD collinear factorization  usually applied at medium energies and the high-energy k-t factorization , in order to understand how these two QCD dynamics are interrelated.
    • Note: The successful candidate will be working in close collaboration with the QCD groups in Ecole Polytechnique and LPT-Orsay (France), Universidade de Santiago de Compostela (Spain) and University of Connecticut (USA). 
  2. Gluon Saturation effects in High-Energy Collisions
    • Supervisor: prof. dr hab. Lech Szymanowski 
    • Auxiliary supervisor: dr Tolga Altinoluk 
    • Description: The microscopic theory describing the structure of protons and nuclei is the theory of strong interactions, known as Quantum ChromoDynamics (QCD). Even though the fundamental theory is known, it is extremely difficult to deduce from the QCD results of collision processes. This is due to the high level of complexity of the theory involving nonlinear interactions between gluons, the “photons” of strong interactions. When probed at very high energies, heavy nuclei, and even protons, appear as very dense clouds of gluons, the phenomena known as Color Glass Condensate (CGC).  The main goal of this PhD project is to investigate the gluon saturation effects through proton-proton and proton-nucleus collisions with the aim of providing a better understanding of the CGC framework. Today, exploring QCD under extreme conditions, such as at high energy/density, is more important than ever due to its extensive exploration at Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory and the Large Hadron Collider (LHC) at CERN, and the proposals for construction of electron-ion colliders. 
    • Note: The successful candidate will be working in close collaboration with the QCD groups in Ecole Polytechnique and LPT-Orsay (France), Universidade de Santiago de Compostela (Spain) and University of Connecticut (USA). 
  3. Alpha-particle clustering in medium mass nuclei
    • Supervisor: dr hab. Nicholas Keeley
    • Description: The degree of alpha-particle clustering in medium mass nuclei, e.g. Ca and Ar isotopes, is a topic of considerable current interest. Sophisticated large-scale modern shell model calculations are able to predict the structure of these nuclei and can quantify the probability of formation of alpha-particle clusters through the medium of the alpha-particle spectroscopic factors, Sα, quantities which can be extracted from experimental measurements and thus compared with the theory, providing an important validation of the calculations. Unfortunately, the Sα are not observables, that is to say they cannot be directly measured, and must be extracted from direct reaction data using a model of the reaction process. This makes the empirical Sα extracted from data “model dependent” quantities and, despite over 40 years of effort, they remain notoriously poorly determined. This project aims to use new data to be obtained at the Heavy Ion Laboratory of the University of Warsaw to carry out comparative studies of different heavy-ion induced alpha-particle transfer reactions – (12C,8Be), (16O,12C), (20Ne,16O) and (24Mg,20Ne) – to attempt to establish a coherent, consistent picture of the alpha-particle clustering in the ground states of stable Ca isotopes. The successful candidate will be expected to carry out all aspects of the setting up and running of the experiments and the data reduction. A major part of the work will consist in modelling the reaction data using state-of-the-art direct reaction codes to extract the Sα. These will be compared with the results of modern large scale shell model calculations. Part of the goal of this work will be to attempt to establish whether one of the reactions in particular is best suited to these studies. Opportunities to participate in experiments at radioactive ion beam facilities elsewhere will also be available, in particular at GANIL, France, and possibly also ISOLDE, CERN, Switzerland, TRIUMF, Vancouver, Canada, and EXOTIC/SPES, Legnaro, Italy.
  4. Exploring the production rate of very heavy nuclei in high-K states
    • Supervisor: dr. hab. Michał Kowal
    • Description: Superheavy elements are extremely unstable systems with very low production cross sections. Existing experimental facilities limit the possibilities for discovery of new nuclides to those synthesized with the cross sections above 100 fb what is possible currently in selected laboratories, actually only in two of them, i.e. in DUBNA and in RIKEN. As the creation of new elements is a very difficult task as a parallel or additional line of study one could try a search for new, long-lived metastable states of already known heavy nuclei. Evaluation of probability of synthesis such heavy nuclei in high-K states via fusion evaporation reactions will be the main topic of this thesis – never done before!
  5. Search for super-stable high-K super-heavy isomers
    • Supervisor: dr. hab. Michał Kowal
    • Description: Due to small structural overlap and strong centrifugal effect transition between non-analogical states are excluded. Different excitation energies of a high-K configuration in parent and daughter nucleus seem than particularly important for a hindrance of the alpha-decay. This, together with their relatively low excitation suggests a possibility that they could be isomers with an extra stability – five and more orders of magnitude longer-lived than the ground states. This in turn would mean that chemical studies of such exotic high-K sates would be more likely than for quite unstable ground states. In this thesis, for the first time, we plan to include into two- and four-quasi particle states additional odd particle effect. We are going to discuss the influence of the odd nucleons on the hindrance mechanism in alpha decay process.
  6. Fission hindrance of high-K isomers in (super) heavy nuclei
    • Supervisor: dr. hab. Michał Kowal
    • Description: Experimental data suggest a mechanism for fission hindrance for high-K isomers similar as that for odd-A nuclei in the whole SH region. The pairing plus- specialization energy (configuration-preserving) mechanism seems to have a too strong effect, as judged from energy landscapes for some odd-A nuclei. However, the current description of fission half-lives, employing adiabatic approximation, is not suitable for odd-A nuclei and isomers. The aim of the work will be to examine the mechanisms responsible for fission hindrance (currently completely unclear) in such heavy exotic nuclear systems and to develop a new method that allows on estimation of the decay half-lives against fission.
  7. UV safe extensions of the Standard Model
    • Supervisor: prof. dr hab. Leszek Roszkowski
    • Auxiliary supervisor: dr Kamila Kowalska
    • Description: A quantum field theory can be considered fundamental if all the couplings and masses remain finite at an arbitrary high energy scale. That is not the case for the Standard Model. One solution to this issue is to unify the three gauge groups of the Standard Model so that the unified coupling constant is asymptotically free. Another possibility is to modify the renormalization group equations in a way that a non-zero fixed-point is generated. The topic of the PhD project is to investigate, both from the theoretical and phenomenological point of view, extensions of the Standard Model that allow to realize one of the above scenarios.
    • Note: This is a grant-funded topic and the standard admissions process must be preceded by a preselection procedure mandated by the National Science Centre. For details please contact the PI, Dr. K. Kowalska.
  8. Phenomenology of vector-like extensions of the Standard Model
    • Supervisor: prof. dr hab. Leszek Roszkowski
    • Auxiliary supervisor: dr Kamila Kowalska
    • Description: There are many reasons to believe that the Standard Model is not the final theory of nature, but we still do not know which of many beyond the Standard Model scenarios is the true one. One of the possibilities considered in the literature is to extend the Standard Model by vector-like fermions. The topic of the PhD project is to investigate phenomenological properties of such scenarios by means of dedicated numerical tools and taking into account large amount of experimental data from the LHC, flavor physics experiments and dark matter searches.
    • Note: This is a grant-funded topic and the standard admissions process must be preceded by a preselection procedure mandated by the National Science Centre. For details please contact the PI, Dr. K. Kowalska.
  9. Study of neutrino interactions on correlated nucleon pairs in the T2K experiment
    • Supervisor: dr hab. Justyna Łagoda
    • Auxiliary supervisor: dr Joanna Zalipska
    • Description: T2K is an experiment searching for neutrino oscillations and measuring cross-sections of neutrino interactions. This project will be focused on investigations of interactions with correlated nucleon pairs, which are still not well known. The candidate will work on the analysis using (anti)neutrino data collected by the near detector of the T2K experiment and will contribute to work dedicated to the upgrade of that detector. The upgrade of the near detector is planned to be finalized in 2021.  The student will contribute to the understanding of detection of low momentum particles. The candidate will collaborate with an international team of physicists; will present his/her work at local meetings in Poland and at collaboration meetings in Japan. It is possible to stay for training period in Japan during the doctoral studies.
    • Note: This is a grant-funded topic and the standard admissions process must be preceded by a preselection procedure mandated by the National Science Centre. For details please contact the PI, Dr. J. Zalipska.
  10. Neutrino interactions in the upgraded T2K Near Detector
    • Supervisor: dr hab. Justyna Łagoda
    • Description: T2K is an experiment searching for neutrino oscillations and measuring cross-sections of neutrino interactions. The upgraded T2K Near Detector opens the possibility to study more precisely the neutrino interactions thanks to its increased angular acceptance and better efficiency for detection of low energy particles. The student will be involved in the process of selection of new interesting samples of interactions and using them to measure the neutrino cross sections and possibly also to improve the sensitivity of T2K oscillation analysis by reducing the flux and cross section systematic errors. The candidate will collaborate with an international team of physicists; will present his/her work at local meetings in Poland and at collaboration meetings in Japan. It is possible to stay for training period in Japan during the doctoral studies.
    • Note: This is a grant-funded topic and the standard admissions process must be preceded by a preselection procedure mandated by the National Science Centre. For details please contact the PI, dr hab. Justyna Łagoda.
  11. New samples for the analysis of neutrino oscillations in the T2K experiment
    • Supervisor: dr hab. Justyna Łagoda
    • Description: T2K is an experiment searching for neutrino oscillations and measuring cross-sections of neutrino interactions.  The upgrade of T2K experiment includes changes in the Far Detector (Super-Kamiokande) and its calibration and reconstruction which allow to improve the detector performance and allow to better study the neutrino oscillations, aiming for observation of the CP violation for neutrinos. The student will work on the search and definition of the new samples of neutrino interactions for the oscillation analysis taking into account the present upgrades of the experiment. The candidate will collaborate with an international team of physicists; will present his/her work at local meetings in Poland and at collaboration meetings in Japan. It is possible to stay for training period in Japan during the doctoral studies.
    • Note: This is a grant-funded topic and the standard admissions process must be preceded by a preselection procedure mandated by the National Science Centre. For details please contact the PI, dr hab. Justyna Łagoda.
  12. Modelling the Evolution of the Primordial Universe
    • Supervisor: prof. dr hab. Jerzy Kowalski-Glikman
    • Auxiliary supervisor: dr Przemysław Małkiewicz
    • Description: The successful candidate will work in the area of classical and quantum cosmology with emphasis on such aspects as perturbation theory in anisotropic cosmological backgrounds, singularity resolution, semiclassical methods and use of observational data. The goal of the project is to develop a novel model explaining the origin of the primordial Universe and its structures.
    • Note: This is a grant-funded topic and the standard admissions process must be preceded by a preselection procedure mandated by the National Science Centre. For details please contact the PI, dr. Przemysław Małkiewicz (Przemyslaw.Malkiewicz@ncbj.gov.pl).
  13. Quantum origin of the primordial structure in the Universe
    • Supervisor: prof. dr hab. Jerzy Kowalski-Glikman
    • Auxiliary supervisor: dr Przemysław Małkiewicz
    • Description: The successful candidate will work in the area of classical and quantum cosmology with emphasis on such aspects as perturbation theory in anisotropic cosmological backgrounds, singularity resolution, semiclassical methods and use of observational data. The goal of the project is to develop a novel model explaining the origin of the primordial Universe and its structures.
    • Note: This is a grant-funded topic and the standard admissions process must be preceded by a preselection procedure mandated by the National Science Centre. For details please contact the PI, dr. Przemysław Małkiewicz (Przemyslaw.Malkiewicz@ncbj.gov.pl).
  14. Study of neutrino interactions in new generation of water Cherenkov telescopes
    • Supervisor: prof dr hab. Ewa Rondio
    • Auxiliary supervisor: dr Piotr Mijakowski
    • Description: The successful candidate will participate in the international research related to development and operation of the a new generation of neutrino telescopes such as KM3NeT (constructed in waters of the Mediterranean Sea, http://www.km3net.org/) or Hyper-Kamiokande or Super-Kamiokande-Gd (both operating in Japan, http://www-sk.icrr.u-tokyo.ac.jp/sk/index-e.html). As a potential member of those international collaborations the candidate will analyze experimental data acquired by the detectors, participate in development of the simulation software and reconstruction tools (based on machine learning and artificial intelligence solutions) and occasional hardware tests. Specifics of the job will depend on the individual preferences of the candidate.
    • Note: This is a grant-funded topic and the standard admissions process must be preceded by a preselection procedure mandated by the National Science Centre. For details please contact the PI, dr Piotr Mijakowski.
  15. Physics of quark-gluon plasma
    • Supervisor: prof. dr hab. Stanisław Mrówczyński
    • Description: Shortly after the Big Bang, hot and dense matter was in a state called the Quark-Gluon Plasma (QGP) where quarks and gluons are deconfined from hadron’s interiors. Studies of QGP, described by the Quantum Chromo-Dynamics (QCD), yields insights into the early Universe and strongly interacting matter under extreme conditions. Relativistic heavy-ion collisions offer a unique possibility to study QGP in terrestrial experiments and to probe properties of the statistical QCD. A transient state of deconfined quarks and gluons is expected to occur at the early stage of nucleus-nucleus collisions. Currently, there are experiments at the Super Proton Synchrotron (SPS) at CERN, at Relativistic Heavy-Ion Collider (RHIC) at Brookhaven National Laboratory (BNL) and at Large Hadron Collider (LHC) at CERN. There is a broad spectrum of theoretical problems to be studied in the context of quark-gluon plasma and relativistic heavy-ion collisions. The problems require various approaches from rather formal methods of quantum field theory to phenomenology of high-energy interactions, from quantum chromodynamics to kinetic theory and hydrodynamics.
  16. Polarization of gamma-ray bursts
    • Supervisor: dr hab. Agnieszka Pollo
    • Description: Gamma Ray Bursts (GRBs) are thought to be the most violent explosions in the Universe. They are linked to hypernovae events or mergers of compact objects (like neutron stars). However, their exact mechanisms are still poorly understood. One way to clarify the properties of their “central engines”, in particular the role of their magnetic field, can be provided by measurements of polarisation of gamma rays from GRBs. The first significant set of such measurements was only recently provided by the POLAR experiment, conducted by Swiss-Chinese-Polish collaboration. The proposed PhD project will mainly be realized in the framework of its successor, the POLAR-2 space project which will be mounted on the Chinese space station planned to be launched in 2024. The successful applicant will contribute to the team effort of the international POLAR-2 collaboration, conducting also scientific research based on already acquired POLAR data. In the first phase of the project, the student will be immediately involved in performance simulations and instrument optimization studies using the simulation framework in the Geant4-based environement. The next step will be comparisons with the first calibration data. Partcipation in hardware tests and/or firmware development are also possible. In paralel, we will study properties of GRBs already observed by the POLAR detector, both with the aim of finding the mechanisms behind them and to prepare the pipelines for the analysis of the coming larger and deeper POLAR-2 data. As the project will be conducted in close collaboration with the international POLAR-2 team, it will require long research visits in Switzerland and/or China.
  17. Evolution of galaxy properties since z ~ 1
    • Supervisor: dr hab. Agnieszka Pollo
    • Description: The VIMOS Public Extragalactic Redshift Survey (VIPERS) is the largest survey of z \sim 1 Universe conducted so far. It provided a wealth of data related to properties of galaxies in the Universe half younger than it is now. The successful candidate will work on successful exploitation of these data, finding evolutionary paths of different populations of galaxies linking galaxies at z \sim 1 to today’s galaxy populations. We would like to study evolution of metallicity of different population of galaxies; test a possibility of using various populations of galaxies as “cosmic chronometers” an /or perform classical and/or machine learning-based studies of evolution of diversity of galaxy populations, their properties and links to the large scale structure elements.
  18. Machine learning techniques for present day and future big cosmological surveys
    • Supervisor: dr hab. Agnieszka Pollo
    • Description: Machine learning techniques are now becoming more and more popular in astronomy, being applied to various tasks, from classification or clustering of data to regression-based parameter reconstruction or deep learning based image analyses. With increasingly rising sizes of sky surveys, application of automated techniques is no more a matter of choice but necessity. The successful candidate will develop and apply machine learning methods for reconstruction of galaxy properties and cosmological studies from present-day and future big sky surveys, with the aim to prepare a methodology for the coming data from the Large Synoptic Survey Telescope.
  19. Study of deeply virtual production of single mesons at COMPASS experiment and the 3D-structure of the nucleons
    • Supervisor: prof. dr hab. Andrzej Sandacz
    • Description: The structure of strongly interacting particles, like nucleons and mesons, is provided by the theory of strong interactions – Quantum Chromo-Dynamics (QCD). In the framework of QCD the internal structure and properties of nucleons and mesons are determined by the interactions between their elementary constituents, quarks and gluons. The objective of the project is an experimental study of the nucleon intrinsic three-dimensional structure in terms of its elementary constituents, which situates this project in the new domain of QCD studies that surpass the commonly used one-dimensional picture. The phenomenological description of the three-dimensional structure is provided by the formalism of Generalised Parton Distributions (GPDs). In this project the GPDs studies will be performed by measuring various observables for processes of exclusive deeply virtual production of mesons. The studies will be carried out in the framework of the COMPASS Collaboration using the data on the scattering of high energy muons off the proton and deuteron targets. The results will improve considerably our knowledge in the domain of research on the three-dimensional nucleon structure by providing the data for GPDs parameterisation in a kinematic range that was not available before. It is expected that the results will be reported at international conferences and published in peer reviewed international journals.
  20. Direct photon production in relativistic heavy-ion collisions measured in the Alice experinet at the CERN Large Hadron Collider
    • Supervisor: prof. dr hab. Teodor Siemiarczuk
    • Description: The direct photons are the unique probes carrying information about the structure of hadrons and characteristics of the hot partonic matter – the quark-gluon plasma (QGP). The latter is a special state of matter consisting of quarks and gluons no longer confined into hadrons. The QGP was presumably the state of matter existing in the Universe some tiny fraction of a second after the Big Bang. After subsequent cooling, the QGP changed to hadrons which we observe today. The QGP can be created artificially in the laboratory in the small Big Bangs in high- energy heavy-ion collisions when the hadronic matter is heated to the temperature of about 150 MeV. The ALICE experiment, one of the four large CERN experiments, is the only one dedicated to the study of the QGP. ALICE consists of 18 detectors. One of them is the unique highly granulated photon spectrometer with high spatial and energy resolution in a wide dynamical range. The photons interact via the electromagnetic force and, due to the weakness of the electromagnetic interaction compared to the strong interaction between hadrons, their free path in the strongly interacting medium is relatively large. They escape from those hot-spots of the hadronic matter with their momenta unchanged providing us with the „snapshots” of the matter in the moment of their production. The aim of this PhD Thesis will be to single out the direct photons from those stemmed from the particles decay, compare their production with the perturbative QCD predictions for hard interactions of partons and seek for the direct thermal photons emitted from the hot fireball of the quark-gluon plasma.
  21. Photon identification in the Alice photon spectrometer with the charged particle veto detector CPV
    • Supervisor: prof. dr hab. Teodor Siemiarczuk
    • Description: The goal of this PhD thesis is to develop algorithms for photon and electron identification in the ALICE photon spectrometer PHOS using information from the charged-particle veto detector installed downstream the PHOS modules. The high energy photons (Eγ > 1 GeV) are identified in PHOS with close to 100% efficiency. The low energy photons (Eγ < 1 GeV) are of special interest as they are expected to have a substantial contribution of thermal direct photos emitted from the quark-gluon plasma produced in relativistic heavy-ion collisions. The contribution of the NLO pQCD direct photons is expected to be negligible in this energy interval whereas the background of charged particles misidentified as photons is not. To get rid of those charged particles, the charged-particle veto detector (CPV) was built and included in the ALICE setup. Neutral particles can be identified in PHOS and CPV if a signal in the PHOS does not match any CPV signals in the vicinity of the PHOS reconstructed photons. Charged particles, on the opposite, are identified as PHOS signals with matching CPV signals. The algorithm for neutral and charged particles identification will be developed using data recorded with PHOS and CPV detectors during the data taking with proton-proton and heavy-ion beams in the ALICE experiment at the CERN Large Hadron Collider. These algorithms will be verified and tuned by using Monte-Carlo simulated data. Criteria of photon and electron identification with PHOS and CPV will be based on the photon and electron identification efficiency and on the particle sample purity. Quality of the found identification criteria will be validated using physical signals consisting of detected photons or electrons, such as pi0, eta, phi, J/psi mesons. The following prerequisites for this Thesis will be quite welcome: programming in C++ and script languages (bash, python). During his doctoral studies, a graduate student is supposed to learn the ALICE software package for simulation, reconstruction and analysis, using distributed computing system GRID for large data sample processing, write standalone algorithms for data analysis. Intermediate results will be regularly discussed at the ALICE working group meetings. The outcome of the analysis is supposed to be presented at the conference and published in the refereed journals.
  22. Dilepton production and search for dark matter in relativistic nucleus-nucleus collisions in NA61/SHINE experiment at CERN SPS
    • Supervisor: prof. dr hab. Joanna Stepaniak
    • Auxiliary supervisor: dr Damian Pszczel
    • Description: The NA61 experiment located at CERN is well suited to study the production of lepton/anti-leptons pairs in high energy collisions of heavy ions. The leptons are not perturbed by strong interactions therefore they constitute a sensitive probe of the properties of the extremely dense state of matter (QGP) that emerges during the collision process. Moreover, there are dark matter models in which a dilepton pair is produced via a dark mediator decay (dark photon with low, yet non-zero mass). The search for dark matter and its properties is a topic of the outermost importance. A large amount of data, which can be a base for such a study, have already been collected and future experiments are planned after year 2020.
  23. Strange baryon production in relativistic nucleus-nucleus collisions in NA61/SHINE experiment at CERN SPS
    • Supervisor – prof. dr hab. Joanna Stepaniak
    • Description: The NA61/SHINE experiment located at CERN is well suited to study the production of strange hyperons and multi-strange baryons in ion-ion collisions at momenta between (12-158) AGeV/c. The ratio of strange to non-strange hadron yield is a function of the incident energy and nucleus dimensions. This observable is interesting as a possible signature of phase transision between hadronic and quark matter. Particle correlations at small relative momenta can provide valuable information about the formation of hyperfragments and even more exotic objects called strangelets. A large amount of data, which can be a base for such a study, have already been collected and future experiments are planned after year 2020.
  24. Vector Boson Scattering with the CMS experiment at the LHC
    • Supervisor: dr hab. Michał Szleper
    • Description: Vector Boson Scattering is a class of processes which probe the Higgs boson properties as well as properties of the intermediate weak bosons W and Z. Together they comprise an important class of experimental tests of the Standard Model of particle physics and indirect searches for new physics carried in the most general theoretical framework of Effective Field Theories. The project will involve analysis of data collected by the CMS experiment during Run II of the LHC. The successful applicant is expected to participate in the analysis of the same-sign WW scattering process, implement the novel “clipping” method to derive the best limits on new physics, and/or develop methods to tag different W polarizations from the data. The project will include also work on the muon trigger system within the Warsaw CMS group.
  25. Formation and evolution of galaxies observed in infrared wavelengths using spectral energy distribution fitting and spectral properties.
    • Supervisor: dr. hab. Agnieszka Pollo
    • Auxiliary supervisor: dr Katarzyna Małek
    • Description: Studies of the physical properties of galaxies are numerous, and various strategies are used. One of the methods is to take advantage of the spectral energy distribution fitting using broadband photometry, the second – to make use of spectral properties of galaxies. In this project, we propose to study both properties simultaneously using energy balance technique. Based on 170 millions of galaxies from the Herschel Extragalactic Legacy Project spanning the redshift range from 0  up to redshift 5 we are going to build the evolutionary paths of galaxies observed in infrared wavelengths depending on their types and properties.
    • Note: This is a grant-funded topic and the standard admissions process must be preceded by a preselection procedure mandated by the National Science Centre. For details please contact the PI, dr Katarzyna Małek.
  26. Searching for different classes of infrared galaxies according to their dust attenuation properties  using machine learning algorithms
    • Supervisor: dr. hab. Agnieszka Pollo
    • Auxiliary supervisor: dr Katarzyna Małek
    • Description: Stars and dust located in galaxies are mutually evolving, and their properties depend on each other. Because the radiation we observe depends on the dust properties and the properties of the stars, simultaneously modelling their properties at the same time is not an easy matter. This complex relationship reflects the law of attenuation or quenching the intensity of the galaxy’s radiation in a given band. Poorly known shape of the damping curve limits the interpretation of the fundamental properties of galaxies.  We plan to apply various machine learning techniques to classify, study properties and look for patterns in the related parameter space for 170 millions of infrared galaxies observed by Herschel satellite to puzzle this issue out.
    • Note: This is a grant-funded topic and the standard admissions process must be preceded by a preselection procedure mandated by the National Science Centre. For details please contact the PI, dr Katarzyna Małek.
  27. Investigation of discrete symmetries CP and CPT and their possible violations
    • Supervisor: prof. dr hab. Wojciech Wiślicki
    • Auxiliary supervisor: Dr Wojciech Krzemień
    • Description: Invariance with respect to discrete transformations of the charge conjugation (C), spatial inversion (P) and time reversal (T), and their combination CP, is known to be violated in weak iteractions of the strange, charm and beauty hadrons. Their triple combination CPT is know to an exact symmetry of nature. Quantitative investigation of violation of CP in decays of charm and beauty is an important for closing up the standard model of interactions and test its validity. Precise measurement of the exactness of CPT conservation constrain possible new phenomena extending beyond known physics. In this PhD project it is proposed to measure CP- and CPT-sensitive quantities in decays of the charm- and beauty-endowed mesons D and B and hyperons containing c or b quark, into hadrons or to the mixed states of hadrons and leptons. It will be performed at the NCBJ group working for the LHCb experiment at CERN in Geneva.
  28. Search for structures and feature formation in multidimensional data sets using machine-learning
    • Supervisor: prof. dr hab. Wojciech Wiślicki
    • Auxiliary supervisor: Dr Lech Raczyński
    • Description: Methods of artificial intelligence are nowadays proved to be powerful in detecting structures, anomalies and proposing new features in big data that cannot be revealed using classical imaging or statistical data analysis methods. This concerns both unsupervised class definitions and supervised classifiers. In this PhD project it is proposed to apply these methods to large data sets from two types of detectors: (i) medical scanner based on the positron-emission tomography J-PET, used for both medical imaging and lesion detection, and for basic physics research on fundamental symmetries of positronium, (ii) diffractive data on structures of molecules or crystals, including dynamical data, coming from new detectors on the large laser on free electrons XFEL, located at DESY in Hamburg. The project involves data-intensive computing using high-performance machines at the NCBJ Computing Centre Świerk, consisting of both the CPU and graphical processors.
  29. Search for hadron exotic states at LHCb experiment at CERN: the nature of Ωc excited hadrons as possible pentaquark states
    • Supervisor: prof. dr hab. Wojciech Wiślicki
    • Auxiliary supervisor: Dr Dmytro Melnychuk
    • Description: Quantum Chromodynamics (QCD) allows for much richer hadron spectrum than conventional mesons and baryons. Such states could consist of 4 or 5 quarks as tetraquarks and pentaquarks and are called exotic from the point of view of naive quark model. In the later years the family of particles containing charm quark and not fitting into charmonium description extended to more then twenty states, labeled as X, Y, Z. Among them there are several candidates for tetraquark states. Recently the family of exotic mesons resonances has been extended by exotic baryon resonances in the J/Ψp final state, as discovered by LHCb. They are labelled as Pc(4312+) and Pc(4450) + and are called pentaquarks, however their true nature is still unknown and is the subject of ongoing investigation. Other good candidates for pentaquark interpretation could be two states of the family of five narrow Ωc excited baryons recently observed by the LHCb experiment at CERN in Geneva. The PhD project concerns the study of existence and structure of such states. It will be performed at the NCBJ’s LHCb group.
  30. Dose Distribution Analysis and Optimisation for Stereotactic Irradiation with a Linear Accelerator
    • Supervisor: dr. hab. Annna Wysocka-Rabin
    • Description: The objective of this work is to perform verification of dose distributions calculated with a treatment planning system (TPS), which will provide the basis for creation of a comprehensive test of TPS for stereotactic radiotherapy (SRT). Monte Carlo (MC) techniques should be used to model the accelerator and to calculate the dose distribution in the patient’s body. Calculated photon beam parameters should be compared with the measurements and should be used as input-data for TPS.
  31. Search for long-lived massive charged particles at the CMS (LHC)
    • Supervisor: dr hab. Piotr Zalewski
    • Auxiliary supervisor: dr Małgorzata Kazana
    • Description: The main weakness of the Standard Model (SM) form the experimental point of view is the lack of a dark matter (DM) candidate. On the other hand the most popular DM candidate from beyond the SM – a Weakly Interacting Massive Particle (WIMP) – starts to be so restricted by direct and collider searches, that alternative models become more and more interesting. A prominent example is a class of models with Extremely WIMPs – like gravitino – as a DM candidate. Such scenarios could be confirmed or excluded only at the LHC by searching for particles decaying to DM ones. Such particles could be long-lived massive and charged. Successful candidate is expected to contribute to such searches using the CMS detector at the LHC. More detailed description is available on request.
    • Note: This is a grant-funded topic and the standard admissions process must be preceded by a preselection procedure mandated by the National Science Centre. For details please contact the PI, piotr.zalewski(at)ncbj.gov.pl