Monografie naukowe (Scientific monographs)

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Badania struktury jąder neutrono-nadmiarowych produkowanych w głęboko nieelastycznych reakcjach ciężkich jonów na wiązkach stabilnych i radioaktywnych
(Institute of Nuclear Physics Polish Academy of Sciences, 2013) Królas, Wojciech
A novel experimental method exploiting the production of neutron-rich fragments in deepinelastic heavy ion collisions was used to extend the in-beam γ-ray spectroscopic studies towards previously inaccessible neutron-rich nuclei. The γ-γ coincidence analysis of reaction products was used to obtain new information on the mechanism of deep-inelastic collisions, in particular on the neutron-to-proton ratio equilibration process. These results were compared to theoretical predictions based on a liquid-drop energy minimization model and a heavy ion phase space exploration model. Neutron-rich potassium isotopes were studied in the bombardments of thick 238U and 208Pb targets with the 48Ca beam. Excited states in the 48K and 49K isotopes were identified for the first time in experiments with the PRISMA-CLARA spectrometer. Based on those identifications the level schemes of predominantly yrast excited states were established from the analysis of GAMMASPHERE γ coincidence data collected for the same reactions. A new 5+ isomer was identified in 48K, the analog of the 7/2– isomer in 47K. Important information on the coupling of the proton-hole and neutron-particle states in the neutron-rich 48K and 49K isotopes was obtained. Systematics of lowest 1/2+, 3/2+, and 7/2– states in odd-odd potassium isotopes were extended beyond the N = 28 line. These results confirm a reordering of the s1/2 and d3/2 proton-hole orbitals for neutronrich potassium isotopes which was interpreted in terms of the evolution of single-particle energies caused by the monopole effect of the tensor force. Experimental efforts aimed at the establishing of the yrast excitations in the series of even neutron-rich nickel isotopes reaching toward the double closed-shell 78Ni isotope are described including the search for the missing 8+ isomeric state in 72Ni. In the analysis of the GAMMASPHERE γ coincidence data from experiments with the 76Ge beam the ground-state band in 72Ni was extended to the 8+ state concluding that this level has a half-life not longer than 20 ns. Based on the established level scheme a large enhancement of the B(E2) transition probability for the 8+ → 6+ transition in 72Ni compared to 70Ni was calculated. This effect is compatible with the predictions of the van Isacker model suggesting a significant lowering of the 6+ seniority υ = 4 level which is calculated to be near the 6+ υ = 2 state. Recent spectroscopic results for less exotic even-even nickel isotopes 64, 66, 68Ni are presented including new spin and parity assignments based on the analysis of angular correlations of γ rays emitted from fragments produced in deep-inelastic collisions with the 64Ni beam. Prospects of new studies of neutron-rich nuclei produced in deep-inelastic collisions using radioactive ion beams of fission fragments are also discussed. Basic technical aspects of the production of such beams are described based on the Holifield Radioactive Ion Beam Facility RIB project. The design and construction details of the Isomer-scope detection setup for the identification and spectroscopy of the isomeric decays in fragments produced in deep-inelastic collisions are presented. Results of the test experiment with a stable 71Ga beam performed at HRIBF are shown. Plans for an upgrade of the Isomer-scope device and its future application for experiment at Oak Ridge and elsewhere are discussed.
Badanie kolektywnych własności jąder atomowych w funkcji temperatury i spinu
(Institute of Nuclear Physics Polish Academy of Sciences, 2013) Kmiecik, Maria
Commissioning, operations and monitoring of the large scale tracking system for the ATLAS experiment
(Institute of Nuclear Physics Polish Academy of Sciences, 2017) Stanecka, Ewa
This monograph describes the control, operation and performance as- pects of the ATLAS Inner Detector at the Large Hadron Collider at CERN. The Inner Detector is a large system with almost 90 mil- lion readout channels. It combines semiconductor devices (pixels and silicon strip) and straw gaseous detectors to measure trajectories of the charged particles emerging from proton-proton collisions and to reconstruct vertices of the interactions. A specialised Detector Con- trol System designed to allow robust and safe operations of the Inner Detector is described. The details of the environmental management projects as well as the tools for monitoring of the radiation levels inside the Inner Detector volume and protection against beam induced acci- dents are given. The improvements done in the Inner Detector during the long technical stop at the LHC to prepare for proton bunches col- lisions every 25 ns, with the energy √ s =14 TeV and instantaneous luminosity ∼ 1 × 10 34 cm− 2 s− 1 are mentioned. Finally, the combined Inner Detector tracking performance at the beginning of the second season of data taking at LHC is presented.
Dwuwymiarowa dozymetria termoluminescencyjna
(Institute of Nuclear Physics Polish Acadmy of Sciences, 2019) Kłosowski, Mariusz
Dwuwymiarowa dozymetria termoluminescencyjna jest metodą szybkiego pomiaru rozkładu dawki w polu promieniowania jonizującego, przy pomocy tzw. powierzchniowych detektorów termoluminescencyjnych. Metodę pomiaru oraz komponenty wchodzące w kład dwuwymiarowego systemu dozymetrycznego systematycznie opracowywano i rozwijano w ostatnich kilkunastu latach w Instytucie Fizyki Jądrowej PAN. Opracowano dwa rodzaje powierzchniowych detektorów termoluminescencyjnych do różnych zakresów dawek oraz technologię ich produkcji. Zaprojektowano i skonstruowano trzy unikatowe czytniki do odczytu powierzchniowego detektorów. Czytniki zostały przystosowane do różnych funkcji i odczytu różnej wielkości detektorów powierzchniowych, od rozmiaru pastylki o średnicy 5 mm do dużych folii o rozmiarze 20cm x 20cm. Dwuwymiarowy system dozymetryczny sprawdził się w wielu aplikacjach dozymetrycznych, takich jak pomiary w polach fotonowych, jonowych, precyzyjnych pomiarach mikrowiązki, rozróżnianiu ekspozycji statycznej od dynamicznej w dozymetrii indywidualnej, a także w pomiarach w kosmosie i w badaniach materiałowych próbek kryształów. Monografia zawiera kompleksowe omówienie systemu termoluminescencyjnej dozymetrii dwuwymiarowej zaczynając od podstaw teoretycznych i podstawowych właściwości materiałów termoluminescencyjnych, omawia technologię produkcji detektorów powierzchniowych, czytniki do pomiarów dwuwymiarowych i właściwości termoluminescencyjne detektorów powierzchniowych. Końcowa część pracy to obszerny rozdział, przedstawiający zastosowania praktyczne systemu dozymetrycznego w różnych dziedzinach dozymetrii promieniowania jonizującego.
Efekty systematyczne w obserwacjach promieni kosmicznych najwyższych energii – wielokrotne rozpraszanie światła
(Institute of Nuclear Physics Polish Academy of Sciences, 2016) Pękala, Jan
Od chwili odkrycia podczas lotu balonowego przez Victora Hessa, promienie kosmiczne nieustanie są przedmiotem badań. Liczne eksperymenty zostały przeprowadzone dla zbadania tych cząstek przybywających do Ziemi z głębi kosmosu. Eksperymenty te z jednej strony poszerzały wiedzę o promieniach kosmicznych, z drugiej zaś, odkrywając część tajemnicy, otwierały pole do dalszych badań. Dziś, po ponad stuleciu od odkrycia, pochodzenie i własności promieni kosmicznych, szczególnie najwyższych energii, ciągle stanowią jedną z największych zagadek astroﬁzyki. Zakres energii cząstek promieniowania kosmicznego docierającego do Ziemi obejmuje wiele rzędów wielkości: od najniższych energii, rzędu 10 7 eV, aż do najwyższych dotychczas zaobserwowanych, przekraczających 10 20 eV. Ze wzrostem energii cząstek obserwujemy potęgowy spadek ich strumienia (rys. 1), co czyni obserwacje promieniowania kosmicznego o najwyższych energiach szczególnie trudnym. Dzięki atmosferze powierzchnia Ziemi jest chroniona przed ciągłym bombardowaniem wysokoenergetycznymi cząstkami - oznacza to jednak, że bezpośrednia obserwacja promieniowania kosmicznego wymaga wyniesienia detektorów ponad gęste warstwy atmosfery, przy użyciu balonów lub satelitów. Dzięki takim właśnie eksperymentom własności promieniowania kosmicznego, takie jak skład i wielkość strumienia, zostały określone z dużą dokładnością przy niższych energiach. Jednak ograniczone rozmiary i czas działania detektorów jakie mogą być wyniesione ponad atmosferę, w połączeniu z malejącym strumieniem cząstek, narzucają granice możliwości badań takimi metodami do energii poniżej ∼ 10 15 eV. Detekcja promieniowania kosmicznego o wyższych energiach możliwa jest natomiast pośrednio, poprzez obserwacje kaskad cząstek wtórnych, czyli tak zwanych wielkich pęków atmosferycznych, wywoływanych przez cząstki pierwotne.
Experimental and Theoretical Studies of Proton Induced Nuclear Spallation
(Institute of Nuclear Physics Polish Academy of Sciences, 2015) Pysz, Krzysztof
Progress in the understanding of the proton induced disintegration of the atomic nuclei at the GeV incident energy range related to the achievements of the PISA (Proton Induced SpAllation) experiment is reported. The scientific motivation of the spallation research is given. Experimental technique as well as the measured distributions of the double differential cross section (d2σ / dΩdE) for spallation products in broad range of bombarding energies and for target nuclei of various masses are presented. Interpretation of obtained results in the frame of a classical two step model utilizing the mechanism of intranuclear cascade for the first phase of the reaction and the statistical evaporation from the thermalized target-like remnant for a second step is described. Significant deficiencies of two step approach in reproducing of the experimental observables related to the dynamic stage of the reaction is indicated. Search for the features of alternatives scenarios of spallation process with the use of phenomenological models is undertaken and the conclusion indicating the need of inclusion to the theoretical description of the reaction the intermediate compound and excited fragments is derived. A new microscopical model (Spallation Model with Cascade++) of the first dynamical phase of a pA reaction is developed. Besides of the binary nuclear interactions a mechanism consisting in a Dynamic Clustering in Nuclear Medium (DCNM) is postulated. The resulting improvement in the theoretical description of the distributions of the Light Charged Particles (LCP) in comparison to the models where only binary interactions are considered is shown.
From Classical to Plasma Tomography
(Institute of Nuclear Physics Polish Academy of Sciences, 2018) Bielecki, Jakub
This monograph is an attempt at a comprehensive treatment of tomographic reconstruction methods with the special emphasis on the application in fusion research. Therefore, the main volume of the book is devoted to tomographic inversion methods that are either commonly used in the fusion research or they have just been developed and published by me or other researchers. However, detailed explanation and discussion of plasma tomography principles would not have been possible without giving an introduction to classical tomographic reconstruction methods. By these classical methods, I mean here analytical and algebraic methods commonly applied not only in medicine but also in many different fields such as geophysics, bioscience or material science. Inversion methods applied in plasma tomography significantly differ from classical ones. This is mostly due to the nature of the data collected in tomographic experiments carried out with fusion devices. The algebraic reconstruction method, shortly described in Chapter 5, can be considered as a link between classical tomographic methods described in the preceding part of the book and reconstruction methods that are specific to fusion research. In fact, most of the reconstruction methods used in fusion science belong indeed to the class of algebraic methods. However, due to the fact that measured data sets are sparse and the reconstruction problem is strongly ill-posed, specific methods that include a regularisation are required. This is shown and discussed in Chapter 6. My main motivation in publishing this work was a desire to share, with the widest possible readership, a comprehensive monograph on plasma tomography. I would expect the target audience to be primarily academics, with a special emphasis on graduate and PhD students from plasma physics and fusion research community. I hope that this book can serve as a self-contained resource for PhD students wishing to extend their knowledge on plasma tomography. I tried to present as many practical applications as possible, focusing mostly on the recent advances made with tokamak devices. I assume the Reader is familiar with the basic concepts of plasma physics and thermonuclear fusion, as well as with basic mathematical apparatus such as linear algebra. The introductory chapters and proofs of presented theorems should help the Reader to immerse into the ideas presented through the book. For the sake of clarity, some detailed information and additional proofs are postponed to the appendices.
Heat Transfer in High Field Superconducting Accelerator Magnets
(Institute of Nuclear Physics Polish Acadmy of Sciences, 2019) Bocian, Dariusz
This monograph comprehensively describes the problem of heat transfer in superconducting accelerator magnets, which generate high magnetic fields and are cooled with superfluid helium at temperature of 1.9 K or normal fluid helium at a temperature of 4.2 K. The main objective of the research presented in the monography was to optimize the heat transfer in superconducting magnets in terms of their operation in accelerators. The magnets are affected by the shower of secondary particles generated by the particles lost from the beam or particle debris from experiments. The optimization of heat transfer in the superconducting magnets is essential for accelerator efficiency during the collection of the data for physics analyses. The quench of magnets stops accelerator operation and affects the integrated luminosity The superconductors are characterized by the critical surface determined by three parameters: the critical temperature (Tc), the critical current density (Jc) and the critical magnetic field (Bc). The particles lost from the beams or coming from the collision debris are hitting the vacuum pipe and generating a shower of secondary particles, which deposits energy in the magnets coils causing increase of the conductor temperature above a critical one and in consequence provokes the quench of magnets. A quench is the transition of a conductor from the superconducting to the normal conducting state which occurs irreversibly in the superconducting magnets if one of the three parameters: the magnetic field, the current density or the temperature exceeds a critical value. In the research described in this monography the studied critical parameter is the temperature and the figure of merit is the energy deposited in the conductor volume at which the quench occurs. This monograph contains the historical background and the overview of existing methods of solving of the heat transfer problem in multilayer systems, for example in the superconducting magnets. An essential part of the monography is the presentation of the original approach to the problem of optimizing the heat flow in superconducting magnets, designed and developed by the author of this monography and the experimental validation of this method carried out in the form of mini-experiments, planned and executed by the author at CERN. In the monograph the details of calculations and measurements for the superconducting magnets currently installed and operating in the LHC are described as well as the status and analysis of superconducting magnets developed for the LHC upgrade in ~2025. The monograph focuses on the heat transfer from the superconductor to the heat exchanger through a multilayer structure made of solid elements and channels occupied by the normal fluid or the superfluid helium. This monography summarizes many years of the author’s work and experience in this field and includes: the description of the model, the summary of the results obtained for the superconducting magnets installed in the LHC, the results of mini-experiments carried out at CERN and FERMILAB and a description of applications of the developed model in the process of design of a new superconducting magnets for the LHC upgrade. The examples of alternative numeric calculations and measurements are briefly discussed and extended bibliography is presented.
Identyfikacja i charakterystyka izotopowych śladów awarii elektrowni jądrowej Fukushima Daiichi
(Institute of Nuclear Physics Polish Acadmy of Sciences, 2019) Kierepko, Renata
11 marca 2011 r. o godzinie 5:46 czasu UTC (14:46 JST) doszło do trzęsienia ziemi u wschodnich wybrzeży Japonii (The Great East Japan Earthquake). Japońska Agencja Meteorologiczna zlokalizowała hipocentrum zdarzenia 130 km na wschód od wybrzeża Sanriku (północno-wschodnia część wyspy Honsi¯u), na głębokości 24 km, na granicy dwóch płyt tektonicznych tj.: północnoamerykańskiej i pacyficznej, w pobliżu Rowu Japońskiego (rys.1.1) [1]. Trzęsienie to, o magnitudzie 9 (M 9) w skali Richtera [2], było jednym z pięciu największych zarejestrowanych w historii trzęsień ziemi na płycie pacyficznej (Chile 1960 (M 9.5), Chile 2010 (M 8.8), Alaska 1964 (M 9.2) i Sumatra 2004 (M 9.2)). Jego następstwem było zaskakująco wysokie tsunami z maximum dochodzącym do 10-15 m (przewidywania 3-6 m) [1]. Zarówno trzęsienie ziemi jak i tsunami wywołały zniszczenia m.in. w elektrowni jądrowej Fukushima Daiichi (FDNPP), doprowadzając do jednej z największych awarii jądrowych w historii.
Insight into phase situation and kinetics of cold- and melt crystallization processes of chiral smectogenic liquid crystals
(Institute of Nuclear Physics Polish Academy of Sciences, 2023) Drzewicz, Anna
Liquid crystals are made up of molecules with an anisotropic shape, which means they have various properties along different directions. This makes them distinct from isotropic liquids because they tend to align themselves with specific rules and create intermediate phases called mesophases of various long-range degrees of spatial order of molecules. As they are cooled down, these partially ordered phases can either become glassy (vitrify) or form crystals. On the other hand, when liquid crystals are heated from a glassy state, they experience a phenomenon known as cold crystallization. This work discusses the studies of the phase situation and the kinetics of non-isothermal and isothermal cold- and melt crystallization of chiral smectogenic liquid crystals belonging to the 3FmX1PhX2r.s series. Compounds under study exhibit differences in the molecular structure, for instance in the terminal non-chiral (‘m’ = 2-7) and chiral (‘r’ = 4-7, ‘s’ = 1, 2) chain lengths, and the fluorosubstitution of the aromatic molecular core (‘X1’, ‘X2’ = H, F). It is found that individual elements of the molecular structure of 3FmX1PhX2r.s influence to varying degrees the occurrence of liquid crystal phases or the nature of both crystallization and vitrification processes.
Measurements of final states with τ leptons in proton-proton collisions using the ATLAS detector at the LHC
(Institute of Nuclear Physics Polish Academy of Sciences, 2013) Kaczmarska, Anna
This monograph describes first analyses of processes with τ leptons in final state that have been performed with proton-proton collision data at the centre-of-mass energy of √s = 7 TeV collected with the ATLAS detector at the LHC. Described studies are based on early data, recorded in 2010 and corresponding to an integrated luminosity of 35 pb−1. Presented Higgs boson(s) searches, requiring higher statistics samples, are based on more data, corresponding to an integrated luminosity of 1.06 fb−1 and collected in 2010 and the first half of 2011. The reconstruction algorithms and identification methods for hadronically decaying τ leptons in the ATLAS experiment are described in detail. Validation of those algorithms in data as well as the first attempts to estimate the rate of the mis-identification of Quantum Chromodynamics jets or electrons as τ candidates are also presented. A dedicated Chapter is devoted to the first measurements of Z → ττ and W → τν production cross sections. The use of the latter process for determination of the hadronic τ decay identification efficiency is also reported. The early analyses of Higgs boson(s) searches with τ leptons in final states, presented in this document, cover studies of both the Standard Model andMinimal Supersymmetric Standard Model neutral Higgs boson(s) decaying into the H → ττ final state as well as Minimal Supersymmetric Standard Model charged Higgs boson decays, H+ → τν. No significant excess over the expected background is observed in any of these studies. Nevertheless, even though performed on limited statistics, they provided improved exclusion limits as compared to those obtained by previous experiments.
Neutrino-Nucleus Cross-Section Measurements in the Near Detector of the T2K Experiment
(Institute of Nuclear Physics Polish Academy of Sciences, 2022) Wąchała, Tomasz
The studies of neutrino-nucleus cross sections play an important role in better understand- ing the mechanisms that rule the neutrino interactions and in more precise measurements of the neutrino oscillation parameters. This monograph is focused on the measurements of neutrino cross sections from the accelerator neutrino beam with the mean energy of 0.7 GeV using the near detector of the T2K experiment. The monograph describes in detail the models of neutrino-nucleus interactions in this energy regime that are currently on the market. It also gives an overview of the world experimental results and outlines the prospects for future cross-section measurements. An entire chapter of this monograph is dedicated to the analyses published by the T2K experiment. The monograph contains a description of the T2K experiment, including the experi- mental setup, research program, and characterization of the Monte Carlo simulation and event reconstruction. A separate chapter is dedicated to the detailed explanation of the techniques and methods used in the cross-section measurements in T2K with a special emphasis on the maximum likelihood approach. Two analyses describing the charged current single charged pion production (CC1π) on water and charged current with no pions on lead and carbon are reported. The measured CC1π total flux-integrated cross section is compatible with Monte Carlo predictions from the NEUT generator. GENIE predictions are within two standard deviations. Further extensions of these studies including the enlarged phase space of the measurement and using more data should allow analysers to compute a differential cross section and minimize the model dependence.
Nowoczesne techniki detekcji promieni kosmicznych ultra-wysokich energii
(Institute of Nuclear Physics Polish Acadmy of Sciences, 2019) Stasielak, Jarosław
Badania nad promieniami kosmicznymi ultra-wysokich energii, powyżej 10¹⁸ eV, prowadzone są przy użyciu olbrzymich detektorów naziemnych rejestrujących wielkie pęki atmosferyczne (kaskady cza˛stek wtórnych) indukowane przez cząstki promieniowania kosmicznego w atmosferze. W ciągu ostatnich lat badania te doprowadziły do znacznego postępu w zrozumieniu promieni kosmicznych. Pomimo tego uzyskane wyniki wciąż nie pozwalają na wyznaczenie źródeł tych najbardziej energetycznych cząstek jakie znamy we Wszechświecie, czy na wyjaśnienie natury obserwowanego stłumienia widma promieni kosmicznych przy energiach większych niż 4 ×10¹⁹ eV. Wyjaśnienie tych zagadnień jest jednym z najważniejszych celów współczesnej astrofizyki. Jednocześnie te same wyniki wskazują że dalsze postępy w badaniach nad promieniami kosmicznymi ultrawysokich energii wymagają zwiększenia możliwości pomiarowych detektorów. Wynika stąd szczególna potrzeba poszukiwania nowych rozwiązań eksperymentalnych umożliwiających poprawienie dokładności pomiarów wielkich pęków, przy jednoczesnej redukcji kosztów budowy i obsługi detektorów. Praca ta poświęcona jest tym zagadnieniom. Przedstawiono w niej nowoczesne techniki detekcji promieni kosmicznych ultrawysokich energii, zarówno klasyczne dobrze sprawdzone metody, jak również i nową radiową metodę detekcji, intensywnie rozwijaną w ciągu ostatniej dekady, z którą obecnie wiąże się duże nadzieje. Omówione zostały również poszukiwania alternatywnych metod na przykładzie prac związanych z technikami mikrofalowej i radarowej detekcji wielkich pęków. Przedstawiono również główne cele i plany rozbudowy największego detektora promieni kosmicznych ultra-wysokich energii jakim jest Obserwatorium Pierre Auger.
PARIS White Book
(Institute of Nuclear Physics Polish Academy of Sciences, 2021) Camera, Franco; Maj, Adam
PARIS is a collaborative international project (http://paris.ifj.edu.pl) to construct and operate a novel gamma-ray calorimeter, which profits wholly or in part from employment of novel, advanced scintillator materials, such as Lanthanum Bromide, and which should have performances superior to any other existing scintillator calorimeter. In fact, PARIS is eminently portable and could be used at different international facilities using both stable or radioactive beams. The present report, the PARIS White Book, is intended to provide a general description of the performances of the PARIS array, of the different laboratories which could, in the next years, host it and of the physics cases that can be addressed by the PARIS array. The presented physics cases are obviously not exhaustive. They simply give some examples where the physical information, provided by the PARIS array, is understood to be the key point for the success of the measurement. As the physics cases will also depend on the detector arrays which will be coupled to PARIS in the future years, and on the beams (stable or radioactive) provided by the hosting laboratory, this list of possible experiments is expected to increase with the years. It is the intention of this White Book to support the collaboration and help to decide on the future PARIS campaigns, as well as on its promising enhancement to 4π.
Perturbed Angular Correlation method in materials science
(Institute of Nuclear Physics Polish Academy of Sciences, 2013) Kulińska, Agnieszka
The nuclear solid state methods involve inter alia the detection of the particles or γ-radiation from the nuclear decays or nuclear reactions to investigate the properties of condensed matter. This extremely broad range of methods can be divided into two main groups: ion beam analysis (IBA) and hyperfine interaction (HFI) techniques. The various methods from the first group are very important for determination of the elemental composition of materials, and for atomic arrangement. The widely used and most well-known technique is the Rutherford Backscattering Spectroscopy (RBS), which is based on the elastic backscattering of charged particles by nuclei in solids. Hyperfine techniques such as the Mössbauer spectroscopy (MS), the Nuclear Magnetic Resonance (NMR), and the Perturbed Angular Correlation (PAC) have been extensively employed to investigate the structural, magnetic and electronic properties at atomic scale in the condensed matter [Sch96]. In this work, I present the use of the PAC method in fundamental research of the condensed matter as well as its application in the solid state and material physics. I give the results of the intensive studies on the intermetallic compounds, oxides, magnetic materials; thin films and nanocrystalline materials. I summarize the EFG parameters for Hf-Al and Zr-Al intermetallic systems.
Photoproduction cross section measurements in ultra-peripheral Pb-Pb and p-Pb collisions at the LHC with ALICE
(Institute of Nuclear Physics Polish Acadmy of Sciences, 2019) Mayer, Christoph
Ultra-peripheral collisions of ultra-relativistic lead ions are a tool for studying g-nucleus or gg interactions at the LHC. Beams of lead ions at the LHC are a source of intense photon fluxes with very high energies, due to the effect of Lorentz contraction and the fact that the equivalent flux of almost real photons around lead ions is proportional to the square of their charge. Since in ultra-peripheral collisions the impact parameter is greater than the sum of the nuclear radii, hadronic interactions are suppressed and electromagnetic interactions dominate. Experimentally, ultra-peripheral collision events are characterized by very low multiplicities in the central rapidity region and rapidity gaps outside central rapidity. In this thesis, photoproduction cross section measurements performed by ALICE (A Large Ion Collider Experiment) in ultra-peripheral collisions are summarized. After a review of ultraperipheral physics in this section, the sub-detectors of ALICE used in ultra-peripheral analyses are described in section 2. Section 3 contains a review of ALICE measurements of r0 photoproduction in Pb-Pb collisions at psNN = 2:76 and 5:02 TeV, and section 4 summarizes ALICE measurements of continuum γγ → e+e- photoproduction in Pb-Pb collisions at psNN = 2:76 TeV. ALICE measurements of J/y photoproduction in Pb-Pb collisions at psNN = 2:76 TeV and in p-Pb collisions at psNN = 5:02 TeV are discussed in section 5. In section 6 detector upgrades for LHC run 3 and 4, and prospects for ultra-peripheral measurements in run 3 and 4 are described. The last section contains a summary and conclusions.
Plasma-Focus and controlled nuclear fusion
(Institute of Nuclear Physics Polish Academy of Sciences, 2016) Scholz, Marek
The dependence of the binding energy per nucleon on the nucleus mass number known in nuclear physics shows that nuclear energy can be produced (emitted) not only in the fission reactions of heavy nuclei, but also in the fusion reactions of light nuclei. In both cases, the production (emission) of energy is equal to the increment of the total binding energy. Thus nuclear fusion reactions, in addition to fission reactions, may be the second major source of energy production on Earth.
Pomiar funkcji struktury protonu w obszarze małych przekazów czteropędu Q2 na akceleratorze HERA
(Institute of Nuclear Physics Polish Academy of Sciences, 2015) Łobodzińska, Ewelina
Production of light neutral mesons in the ALICE experiment at the LHC
(Institute of Nuclear Physics Polish Acadmy of Sciences, 2019) Matyja, Adam
Light pseudo-scalar neutral mesons have been studied in e+eˉ, hadron-hadron, hadron-nucleus and nuclear collisions for decades. The results associated with neutral mesons provide information that is as good as that which comes from charged pions or hadrons. However, they have the advantage that they are not affected by Coulomb forces as charged pions. Due to the fact that the differential cross-section can be factorized into short distance (perturbative) and long distance (non-perturbative) terms when sufficiently large momentum transfer occurs, the measurement of neutral meson spectra provides a chance to test NLO or NNLO pQCD calculations or to constrain parton distribution and fragmentation functions. The existence of the Quark-Gluon Plasma (QGP) state was postulated in seventies of the last century. The QGP is a highly dense and hot QCD medium in thermal equilibrium where quarks and gluons are almost free. The strongly interacting QGP state has been discovered at RHIC experiments in heavy-ion collisions and is also formed in nuclear collisions at the LHC. The QGP properties can be probed with neutral mesons. Hard (high pT) partons are produced in hard scatterings at the early stage of a collision. Hard partons interact with the dense QGP medium, lose energy, and emerge as quenched jets in the final state after hadronization. Modification of a jet energy results also in reduction of the energy of leading hadrons and in particular neutral mesons. This phenomenon, known as jet quenching, can be quantified via the nuclear modification factor which shows a large suppression of hadron yields at high pT in the most central AA collisions compared to pp collisions scaled by the number of nucleon-nucleon binary collisions. Thus, the measurement of neutral meson spectra constrains mechanisms of parton energy loss in dense systems via studies of the nuclear modification factor. The ALICE experiment has been designed to study the Quark-Gluon Plasma. However, not only heavy-ion collisions but also pp and pA collisions can be studied there. The π° and η mesons are reconstructed in ALICE mainly via their photonic decays. Photons can be directly measured in ALICE electromagnetic alorimeters, EMCal and PHOS or reconstructed from e+eˉ pairs which come from photon conversion in the central barrel detectors’ material. Calibration of detectors in which photons and electrons are identified plays a very important role. In this context, alibration of two detectors, the Time Projection Chamber (TPC) and the Electromagnetic Calorimeter (EMCal), of the ALICE detector is explained. The overview of the world results for many hadron-hadron, nucleus-nucleus and hadron-nucleus collisions collected in a very wide range of center-of-mass collision energy, from few GeV to few TeV, is given in the paper. Thanks to the LHC accelerator which provided pp collisions in the energy range √s = 0.9 to 13 TeV, p-Pb collisions at √sNN = 5.02 and 8.16 TeV, as well as Pb-Pb collisions at √sNN = 2.76 and 5.02 TeV, the ALICE experiment could extend neutral meson measurements to new energies unavailable before the LHC era. Inclusive π° and η meson production spectra have been measured in a wide pT range at mid-rapidity. The nuclear modification factor shows the large suppression in the central Pb-Pb collisions. The existence of strongly interacting QGP state of matter is confirmed. No suppression is observed in p-Pb collisions, which supports the thesis that suppression is a final state effect. The measured η/ π° ratio shows universal behaviour among systems and energies. However, deviation from mT scaling in very low pT range is indicated. The results from the ALICE experiment give new constraints on various models in both perturbative and non-perturbative regimes. Data collected by ALICE in pp collisions at √s = 13 TeV can provide very precise measurement of neutral meson spectra and information about jet fragmentation. Future measurements of neutral meson production spectra and isolated photon - jet correlations in pp collisions at √s = 13 TeV are discussed.
Przemiany strukturalne i magnetyczne wywołane absorpcją wodoru w związkach ziem rzadkich z manganem o strukturze typu faz Lavesa C14 i C15
(Institute of Nuclear Physics Polish Academy of Sciences, 2012) Budziak, Andrzej

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