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BACKGROUND: Sialadenoses are often diagnosed as concomitant with certain human diseases. At the initial disease stage, it is not always possible to establish the causative pathological process. Omega-3 fatty acids have great effects on humans. The most important Omega-3 fatty acids are actively involved in the metabolism, are the building materials of cells, and help in the prevention of certain diseases. AIM: The Omega-3 levels in 20 patients were examined. Moreover, levels of Omega-3 in 20 patients with sialadenosis were measured before and after treatment with Omega-3 to determine the functional activity of the salivary glands depending on the concentrations in the tissues. MATERIAL AND METHODS: Polyunsaturated Omega-3 fatty acid is the collective name of several fatty acids; although they are not synthesized in the right quantities in humans, they are necessary for maintaining health. The most important Omega-3 fatty acids are actively involved in the metabolism and help in the prevention of cardiovascular diseases, depression, and impaired tissue microcirculation, substantially affecting the human body. RESULTS: The Omega-3 index before treatment was significantly reduced in all patients with sialadenosis, and it significantly increased (p 0.001) after treatment in both women and men. Moreover, the secretory function of the salivary glands significantly improved, the viscosity decreased, and the pH of the mixed saliva was restored. CONCLUSION: The results of this study revealed normalization of the Omega-3 index level in the erythrocyte membrane after treatment with Omega-3, improvement of the secretory activity of the salivary glands, reduction of viscosity, and restoration of the pH of mixed saliva.

BACKGROUND: Sialadenoses are often diagnosed as concomitant with certain human diseases. At the initial disease stage, it is not always possible to establish the causative pathological process. Omega-3 fatty acids have great effects on humans. The most important omega-3 fatty acids are actively involved in the metabolism, are the building materials of cells, and help in the prevention of certain diseases. AIM: The omega-3 levels in 20 patients were examined. Moreover, levels of omega-3 in 20 patients with sialadenosis were measured before and after treatment with omega-3 to determine the functional activity of the salivary glands depending on the concentrations in the tissues. MATERIAL AND METHODS: Polyunsaturated omega-3 fatty acid is the collective name of several fatty acids; although they are not synthesized in the right quantities in humans, they are necessary for maintaining health. The most important omega-3 fatty acids are actively involved in the metabolism and help in the prevention of cardiovascular diseases, depression, and impaired tissue microcirculation, substantially affecting the human body. RESULTS: The omega-3 index before treatment was significantly reduced in all patients with sialadenosis, and it significantly increased (p 0.001) after treatment in both women and men. Moreover, the secretory function of the salivary glands significantly improved, the viscosity decreased, and the pH of the mixed saliva was restored. CONCLUSION: The results of this study revealed normalization of the omega-3 index level in the erythrocyte membrane after treatment with omega-3, improvement of the secretory activity of the salivary glands, reduction of viscosity, and restoration of the pH of mixed saliva.

BACKGROUND: Dry mouth (xerostomia) can be a symptom of various diseases of human organs and systems and caused by prolonged intake of medications as well as chemoradiation treatment of malignant tumors of the maxillofacial area. Xerostomia treatment remains a challenging task. AIM: This study aimed to improve the treatment methods of patients with xerostomia. MATERIAL AND METHODS: Fifty patients with xerostomia were treated and distributed into two groups. Group 1 consisted of 23 patients treated with Hiposalix spray (France). Group 2 included 27 patients treated using the Xerostom (Spain) saliva substitute. All patients underwent sialometry, sialography, and study of the secretion viscosity before and after treatment. RESULTS: At 1 month after treatment, 22 (96%) patients of group 1 noted an improvement. At the same time, an objective increase in the secretion level was detected in 2 (9%) patients. All patients of group 2 noted significant improvement in the condition of the oral cavity. However, sialometry showed that the level of saliva secretion remained the same. CONCLUSIONS: Thus, the use of saliva substitutes produced by Hiposalix and Xerostom significantly reduced or prevented the subjective sensation of dry mouth without an objective increase in saliva secretion.

The authors conducted a comparative clinical and laboratory analysis of patients suffering from hypogonadism and sialadenosis before and after endocri-nological and dental treatment. The results obtained allowed us to conclude that sialadenosis, which occurred in patients with a deficiency of steroid hormones, had no special symptoms and it was clinically hidden for both patients and General practitioners. The most typical symptoms of sialadenosis were: an increase in LF, decrease in the level of secretion and the increase in the viscosity of mixed saliva. The results of complex treatment of patients with sialadenosis on the background of Hypo-nadism were the best than only mono-dental treatment. The obtained data indicate the need for complex dental and endocrinological treatment of patients with sialadenosis on the background of hypogonadism.

Combining laser spectroscopy in a Versatile Arc Discharge and Laser Ion Source, with Penning-trap mass spectrometry at the CERN-ISOLDE facility, this work reports on mean-square charge radii of neutron-rich mercury isotopes across the $N = 126$ shell closure, the electromagnetic moments of $^{207}$Hg and more precise mass values of $^{206-208}$Hg. The odd-even staggering (OES) of the mean square charge radii and the kink at $N = 126$ are analyzed within the framework of covariant density functional theory (CDFT), with comparisons between different functionals to investigate the dependence of the results on the underlying single-particle structure. The observed features are defined predominantly in the particle-hole channel in CDFT, since both are present in the calculations without pairing. However, the magnitude of the kink is still affected by the occupation of the $1i_{11/2}$ and $2g_{9/2}$ orbitals with a dependence on the relative energies as well as pairing., 20 pages, 12 figures, Phys. Rev. C in press

The authors indicated that pronounced deformities of the ducts of the large salivary glands occur in 70% of patients with chronic sialadenitis. Due to the fact that conservative treatment of ductal sialadenitis, especially pronounced, does not give long-term results, the authors proposed various methods of surgical treatment of ductal sialadenitis, which have a low level of trauma of collateral tissues and provides a stable long-term result.

Two new mechanisms active in rotating nuclei located in the vicinity of neutron drip line have been discovered. Strong Coriolis interaction acting on high-$j$ orbitals transforms particle-unbound (resonance) nucleonic configurations into particle-bound ones with increasing angular momentum. The point of the transition manifests the birth of particle-bound rotational bands. Alternative possibility of the transition from particle-bound to resonance rotational band (the death of particle-bound rotational bands) with increasing spin also exists but it is less frequent in the calculations. The birth of particle-bound rotational bands provides a mechanism for the extension of nuclear landscape to neutron numbers which are larger than those of the neutron drip line in non-rotating nuclei., 7 pages, 6 figures

The properties of toroidal hyperheavy even-even nuclei and the role of toroidal shell structure are extensively studied within covariant density functional theory. The general trends in the evolution of toroidal shapes in the $Z\approx 130-180$ region of nuclear chart are established for the first time. These nuclei are stable with respect of breathing deformations. The most compact fat toroidal nuclei are located in the $Z\approx 136, N\approx 206$ region of nuclear chart, but thin toroidal nuclei become dominant with increasing proton number and on moving towards proton and neutron drip lines. The role of toroidal shell structure, its regularity, supershell structure, shell gaps as well as the role of different groups of the pairs of the orbitals in its formation are investigated in detail. The lowest in energy solutions at axial symmetry are characterized either by large shell gaps or low density of the single-particle states in the vicinity of the Fermi level in at least one of the subsystems (proton or neutron). Related quantum shell effects are expected to act against the instabilities in breathing and sausage deformations for these subsystems. The investigation with large set of covariant energy density functionals reveals that substantial proton $Z=154$ and 186 and neutron $N=228$, 308 and 406 spherical shell gaps exist in all functionals. The nuclei in the vicinity of the combination of these particle numbers form the islands of stability of spherical hyperheavy nuclei. The study suggests that the $N=210$ toroidal shell gap plays a substantial role in the stabilization of fat toroidal nuclei., 25 pages, 19 figures, submitted to Physical Review C, revised version with suggestions of referee taken into account

A systematic global investigation of pairing properties based on all available experimental data on pairing indicators has been performed for the first time in the framework of covariant density functional theory. It is based on separable pairing interaction of Ref. [1]. The optimization of the scaling factors of this interaction to experimental data clearly reveals its isospin dependence in neutron subsystem. However, the situation is less certain in proton subsystem since similar accuracy of the description of pairing indicators can be achieved both with isospin-dependent and mass-dependent scaling factors. The differences in the functional dependencies of scaling factors lead to the uncertainties in the prediction of proton and neutron pairing properties which are especially pronounced at high isospin and could have a significant impact on some physical observables. For a given part of nuclear chart the scaling factors for spherical nuclei are smaller than those for deformed ones; this feature exists also in non-relativistic density functional theories. Its origin is traced back to particle-vibration coupling in odd-$A$ nuclei which is missing in all existing global studies of pairing. Although the present investigation is based on the NL5(E) covariant energy density functional (CEDF), its general conclusions are expected to be valid also for other CEDFs built at the Hartree level., 19 pages, 10 figures, Physical Review C in press

The mean-square charge radii of $^{207,208}$Hg ($Z=80, N=127,128$) have been studied for the first time and those of $^{202,203,206}$Hg ($N=122,123,126$) remeasured by the application of in-source resonance-ionization laser spectroscopy at ISOLDE (CERN). The characteristic \textit{kink} in the charge radii at the $N=126$ neutron shell closure has been revealed, providing the first information on its behavior below the $Z=82$ proton shell closure. A theoretical analysis has been performed within relativistic Hartree-Bogoliubov and non-relativistic Hartree-Fock-Bogoliubov approaches, considering both the new mercury results and existing lead data. Contrary to previous interpretations, it is demonstrated that both the kink at $N=126$ and the odd-even staggering (OES) in its vicinity can be described predominately at the mean-field level, and that pairing does not need to play a crucial role in their origin. A new OES mechanism is suggested, related to the staggering in the occupation of the different neutron orbitals in odd- and even-$A$ nuclei, facilitated by particle-vibration coupling for odd-$A$ nuclei.

The systematic investigation of the ground state and fission properties of even-even actinides and superheavy nuclei with $Z=90-120$ from the two-proton up to two-neutron drip lines with proper assessment of systematic theoretical uncertainties has been performed for the first time in the framework of covariant density functional theory (CDFT). These results provide a necessary theoretical input for the r-process modeling in heavy nuclei and, in particular, for the study of fission recycling. Four state-of-the-art globally tested covariant energy density functionals (CEDFs), namely, DD-PC1, DD-ME2, NL3* and PC-PK1, representing the major classes of the CDFT models are employed in the present study. Ground state deformations, binding energies, two neutron separation energies, $\alpha$-decay $Q_{\alpha}$ values and half-lives and the heights of fission barriers have been calculated for all these nuclei. Theoretical uncertainties in these physical observables and their evolution as a function of proton and neutron numbers have been quantified and their major sources have been identified. Spherical shell closures at $Z=120$, $N=184$ and $N=258$ and the structure of the single-particle (especially, high-$j$) states in their vicinities as well as nuclear matter properties of employed CEDFs are two major factors contributing into theoretical uncertainties. However, different physical observables are affected in a different way by these two factors. For example, theoretical uncertainties in calculated ground state deformations are affected mostly by former factor, while theoretical uncertainties in fission barriers depend on both of these factors., Comment: 28 pages, 18 figures, Physical Review C, in press

The phenomenon of reflection-asymmetric nuclear shapes is relevant to nuclear stability, nuclear spectroscopy, nuclear decays and fission, and the search for new physics beyond the standard model. Global surveys of ground-state octupole deformation, performed with a limited number of models, suggest that the number of pear-shaped isotopes is fairly limited across the nuclear landscape. We carry out global analysis of ground-state octupole deformations for particle-bound even-even nuclei with $Z \leq 110$ and $N \leq 210$ using nuclear density functional theory (DFT) with several non-relativistic and covariant energy density functionals. In this way, we can identify the best candidates for reflection-asymmetric shapes. The calculations are performed in the frameworks of axial reflection-asymmetric Hartree-Fock-Bogoliubov theory and relativistic Hartree-Bogoliubov theory using DFT solvers employing harmonic oscillator basis expansion. We consider five Skyrme and four covariant energy density functionals. We predict several regions of ground-state octupole deformation. In addition to the "traditional" regions of neutron-deficient actinide nuclei around $^{224}$Ra and neutron-rich lanthanides around $^{146}$Ba, we identified vast regions of reflecion-asymmetric shapes in very neutron-rich nuclei around $^{200}$Gd and $^{288}$Pu, as well as in several nuclei around $^{112}$Ba. Our analysis suggests several promising candidates with stable ground-state octupole deformation, primarily in the neutron-deficient actinide region, that can be reached experimentally. Detailed comparison between Skyrme and covariant models is performed., 13 pages, 7 figures

High-spin rotational bands in rare-earth Er ($Z=68$), Tm ($Z=69$) and Yb ($Z=70$) isotopes are investigated by three different nuclear models. These are (i) the cranked relativistic Hartree-Bogoliubov (CRHB) approach with approximate particle number projection by means of the Lipkin-Nogami (LN) method, (ii) the cranking covariant density functional theory (CDFT) with pairing correlations treated by a shell-model-like approach (SLAP) or the so called particle-number conserving (PNC) method, and (iii) cranked shell model (CSM) based on the Nilsson potential with pairing correlations treated by the PNC method. A detailed comparison between these three models in the description of the ground state rotational bands of even-even Er and Yb isotopes is performed. The similarities and differences between these models in the description of the moments of inertia, the features of band crossings, equilibrium deformations and pairing energies of even-even nuclei under study are discussed. These quantities are considered as a function of rotational frequency and proton and neutron numbers. The changes in the properties of the first band crossings with increasing neutron number in this mass region are investigated. On average, a comparable accuracy of the description of available experimental data is achieved in these models. However, the differences between model predictions become larger above the first band crossings. Because of time-consuming nature of numerical calculations in the CDFT-based models, a systematic study of the rotational properties of both ground state and excited state bands in odd-mass Tm nuclei is carried out only by the PNC-SCM. With few exceptions, the rotational properties of experimental 1-quasiparticle and 3-quasiparticle bands in $^{165,167,169,171}$Tm are reproduced reasonably well., 29 pages, 18 figures. submitted to Physical Review C, revised version with takes into account the suggestions of referee

The possibility of the $^{14}\mathrm{C}$ cluster being a basic building block of medium-mass nuclei is discussed. Although $\ensuremath{\alpha}$ cluster structures have been widely discussed in the light $N\ensuremath{\approx}Z$ mass region, the neutron-to-proton ratio deviates from unity in the nuclei near $\ensuremath{\beta}$-stability line and in neutron-rich nuclei. Thus, more neutron-rich objects with $NgZ$ could become the building blocks of cluster structures in such nuclei. The $^{14}\mathrm{C}$ nucleus is strongly bound and can be regarded as such a candidate. In addition, the path to the lowest shell-model configuration at short relative distances is closed for the $^{14}\mathrm{C}+^{14}\mathrm{C}$ structure, contrary to the case of the $^{12}\mathrm{C}+^{12}\mathrm{C}$ structure; this allows an appreciable separation distance between the $^{14}\mathrm{C}$ clusters. The recent development of the antisymmetrized quasicluster model (AQCM) allows us to utilize a $jj$-coupling shell-model wave function for each cluster in a simplified way. The AQCM results for the $^{14}\mathrm{C}+^{14}\mathrm{C}$ structure in $^{28}\mathrm{Mg}$ are compared with the ones of cranked relativistic mean field (CRMF) calculations. Although theoretical frameworks of these two models are quite different, they give similar results for the nucleonic densities and rotational properties of the structure under investigation. The existence of a linear chain three-$^{14}\mathrm{C}$ cluster structure in $^{42}\mathrm{Ar}$ has also been predicted in AQCM. These results confirm the role of the $^{14}\mathrm{C}$ cluster as a possible building block of cluster structures in medium-mass nuclei.

What are the limits of the existence of nuclei? What are the highest proton numbers $Z$ at which the nuclear landscape and periodic table of chemical elements cease to exist? These deceivably simple questions are difficult to answer especially in the region of hyperheavy ($Z\geq 126$) nuclei. We present the covariant density functional study of different aspects of the existence and stability of hyperheavy nuclei. For the first time, we demonstrate the existence of three regions of spherical hyperheavy nuclei centered around ($Z\sim 138, N\sim 230$), ($Z\sim 156, N\sim 310$) and ($Z\sim 174, N\sim 410$) which are expected to be reasonably stable against spontaneous fission. The triaxiality of the nuclei plays an extremely important role in the reduction of the stability of hyperheavy nuclei against fission. As a result, the boundaries of nuclear landscape in hyperheavy nuclei are defined by spontaneous fission and not by the particle emission as in lower $Z$ nuclei. Moreover, the current study suggests that only localized islands of stability can exist in hyperheavy nuclei., 13 pages (including supplementary information), submitted to Physics Letters B, revised version of the manuscript with some additional information included

A systematic analysis of the ground state and fission properties of actinides and superheavy nuclei important for the r process modeling has been performed within the framework of covariant density functional theory for the first time in Ref. [1]. A brief review of the results related to the heights of primary fission barriers and systematic uncertainties in their prediction is presented. In addition, new results on the potential impact of the isospin dependence of pairing on fission barriers in fission cycling regions is provided for the first time.

We calculate field isotope shifts for nobelium atoms using nuclear charge distributions which come from different nuclear models. We demonstrate that comparing calculated isotope shifts with experiment can serve as a testing ground for nuclear theories. It also provides a way of extracting parameters of nuclear charge distribution beyond nuclear RMS radius, e.g. parameter of quadrupole deformation $\beta$. We argue that previous interpretation of the isotope measurements in terms of $\delta \langle r^2 \rangle$ between $^{252,254}$No isotopes should be amended when nuclear deformation is taken into account. We calculate isotope shifts for other known isotopes and for hypothetically metastable isotope $^{286}$No for which the predictions of nuclear models differ substantially., Comment: 7 pages, 2 figures

Parametric correlations are studied in several classes of covariant density functional theories (CDFTs) using a statistical analysis in a large parameter hyperspace. In the present manuscript, we investigate such correlations for two specific types of models, namely, for models with density dependent meson exchange and for point coupling models. Combined with the results obtained previously in Ref. [1] for a non-linear meson exchange model, these results indicate that parametric correlations exist in all major classes of CDFTs when the functionals are fitted to the ground state properties of finite nuclei and to nuclear matter properties. In particular, for the density dependence in the isoscalar channel only one parameter is really independent. Accounting for these facts potentially allows one to reduce the number of free parameters considerably., 8 pages, 4 figures and supplemental material in suppl.pdf, Physics Letters B in press

The properties of hyperheavy nuclei and the extension of nuclear landscape to hyperheavy nuclei are extensively studied within covariant density functional theory. Axial reflection symmetric and reflection asymmetric relativistic Hartree-Bogoliubov (RHB) calculations are carried out. The role of triaxiality is studied within triaxial RHB and triaxial relativistic mean field + BCS frameworks. With increasing proton number beyond Z~130 the transition from ellipsoidal-like nuclear shapes to toroidal ones takes place. The description of latter shapes requires the basis which is typically significantly larger than the one employed for the description of ellipsoidal-like shapes. Many hyperheavy nuclei with toroidal shapes are expected to be unstable towards multifragmentation. However, three islands of stability of spherical hyperheavy nuclei have been predicted for the first time in Ref. [1]. Proton and neutron densities, charge radii, neutron skins and underlying shell structure of the nuclei located in the centers of these islands have been investigated in detail. Large neutron shell gaps at N=228, 308 and 406 define approximate centers of these islands in neutron number. On the contrary, large proton gap appear only at Z=154 in the (Z~156, N~310) island. As a result, this is the largest island of stability of spherical hyperheavy nuclei found in the calculations. The calculations indicate the stability of the nuclei in these islands with respect of octupole and triaxial distortions. Fission barriers in neutron-rich superheavy nuclei are studied in triaxial RHB framework; the impact of triaxiality on the heights of fission barriers is substantial in some parts of this region. Based on the results obtained in the present work, the extension of nuclear landscape to hyperheavy nuclei is provided., Comment: 30 pages, 22 figures, Physical Review C, in press

Statistical errors in ground state observables and single-particle properties of spherical even-even nuclei and their propagation to the limits of nuclear landscape have been investigated in covariant density functional theory (CDFT) for the first time. In this study we consider only covariant energy density functionals with non-linear density dependency. Statistical errors for binding energies and neutron skins significantly increase on approaching two-neutron drip line. On the contrary, such a trend does not exist for statistical errors in charge radii and two-neutron separation energies. The absolute and relative energies of the single-particle states in the vicinity of the Fermi level are characterized by low statistical errors ($\sigma(e_i)\sim 0.1$ MeV). Statistical errors in the predictions of spin-orbit splittings are rather small. Statistical errors in physical observables are substantially smaller than related systematic uncertainties. Thus, at the present level of the development of theory, theoretical uncertainties at nuclear limits are dominated by systematic ones. Statistical errors in the description of physical observables related to the ground state and single-particle degrees of freedom are typically substantially lower in CDFT as compared with Skyrme density functional theory. The correlations between the model parameters are studied in detail. The parametric correlations are especially pronounced for the $g_2$ and $g_3$ parameters which are responsible for the density dependence of the model. The accounting of this fact potentially allows to reduce the number of free parameters of non-linear meson coupling model from six to five.

The impact of beyond mean field effects on the ground state and fission properties of superheavy nuclei has been investigated in a five-dimensional collective Hamiltonian based on covariant density functional theory. The inclusion of dynamical correlations reduces the impact of the $Z=120$ shell closure and induces substantial collectivity for the majority of the $Z=120$ nuclei which otherwise are spherical at the mean field level (as seen in the calculations with the PC-PK1 functional). Thus, they lead to a substantial convergence of the predictions of the functionals DD-PC1 and PC-PK1 which are different at the mean field level. On the contrary, the predictions of these two functionals remain distinctly different for the $N=184$ nuclei even when dynamical correlations are included. These nuclei are mostly spherical (oblate) in the calculations with PC-PK1 (DD-PC1). Our calculations for the first time reveal significant impact of dynamical correlations on the heights of inner fission barriers of superheavy nuclei with soft potential energy surfaces, the minimum of which at the mean field level is located at spherical shape. These correlations affect the fission barriers of the nuclei, which are deformed in the ground state at the mean field level, to a lesser degree., Comment: 11 pages, 8 figures,Physical Review C, in press

High spin band structures of neutron-rich $^{152--158}\mathrm{Pm}$ isotopes have been obtained from the measurement of prompt $\ensuremath{\gamma}$ rays of isotopically identified fragments produced in fission of $^{238}\mathrm{U}+^{9}\mathrm{Be}$ and detected using the VAMOS++ magnetic spectrometer and EXOGAM segmented Clover array at GANIL and also from the high statistics $\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}$ and $\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}$ data from the spontaneous fission of $^{252}\mathrm{Cf}$ using Gammasphere. The excited states in $^{157}\mathrm{Pm}$ and those above the isomers in even-$A$ Pm isotopes $^{152,154,156,158}\mathrm{Pm}$ have been identified for the first time. The spectroscopic information on the rotational band structures in odd-$A$ Pm isotopes has been extended considerably to higher spins and the possibility of the presence of reflection asymmetric shapes is explored. The configuration assignments are based on the results of cranked relativistic Hartree-Bogoliubov calculations. From the systematics of bands in odd-$A$ Pm isotopes and weak population of opposite parity bands, octupole deformed shapes in neutron-rich Pm isotopes beyond $N=90$ seem unlikely to be present.

The nodal structure of the density distributions of the single-particle states occupied in rod-shaped, hyper- and megadeformed structures of nonrotating and rotating $N\ensuremath{\sim}Z$ nuclei has been investigated in detail. The single-particle states with the Nilsson quantum numbers of the $[NN0]1/2$ (with $N$ from 0 to 5) and $[N,N\ensuremath{-}1,1]\mathrm{\ensuremath{\Omega}}$ (with $N$ from 1 to 3 and $\mathrm{\ensuremath{\Omega}}=1/2$, 3/2) types are considered. These states are building blocks of extremely deformed shapes in the nuclei with mass numbers $A\ensuremath{\le}50$. Because of (near) axial symmetry and large elongation of such structures, the wave functions of the single-particle states occupied are dominated by a single basis state in cylindrical basis. This basis state defines the nodal structure of the single-particle density distribution. The nodal structure of the single-particle density distributions allows us to understand in a relatively simple way the necessary conditions for $\ensuremath{\alpha}$ clusterization and the suppression of the $\ensuremath{\alpha}$ clusterization with the increase of mass number. It also explains in a natural way the coexistence of ellipsoidal mean-field-type structures and nuclear molecules at similar excitation energies and the features of particle-hole excitations connecting these two types of the structures. Our analysis of the nodal structure of the single-particle density distributions does not support the existence of quantum liquid phase for the deformations and nuclei under study.

Statistical errors in ground state observables and single-particle properties of spherical even-even nuclei and their propagation to the limits of nuclear landscape have been investigated in covariant density functional theory (CDFT) for the first time. In this study we consider only covariant energy density functionals with non-linear density dependency. Statistical errors for binding energies and neutron skins significantly increase on approaching two-neutron drip line. On the contrary, such a trend does not exist for statistical errors in charge radii and two-neutron separation energies. The absolute and relative energies of the single-particle states in the vicinity of the Fermi level are characterized by low statistical errors ($\sigma(e_i)\sim 0.1$ MeV). Statistical errors in the predictions of spin-orbit splittings are rather small. Statistical errors in physical observables are substantially smaller than related systematic uncertainties. Thus, at the present level of the development of theory, theoretical uncertainties at nuclear limits are dominated by systematic ones. Statistical errors in the description of physical observables related to the ground state and single-particle degrees of freedom are typically substantially lower in CDFT as compared with Skyrme density functional theory. The correlations between the model parameters are studied in detail. The parametric correlations are especially pronounced for the $g_2$ and $g_3$ parameters which are responsible for the density dependence of the model. The accounting of this fact potentially allows to reduce the number of free parameters of non-linear meson coupling model from six to five., Comment: 18 pages, 9 figures, submitted to Physical Review C, referee suggestions are taken into account

X-ray observations of transiently accreting neutron stars during quiescence provide information about the structure of neutron star crusts and the properties of dense matter. Interpretation of the observational data requires an understanding of the nuclear reactions that heat and cool the crust during accretion, and define its nonequilibrium composition. We identify here in detail the typical nuclear reaction sequences down to a depth in the inner crust where the mass density is 2E12 g/cm^3 using a full nuclear reaction network for a range of initial compositions. The reaction sequences differ substantially from previous work. We find a robust reduction of crust impurity at the transition to the inner crust regardless of initial composition, though shell effects can delay the formation of a pure crust somewhat to densities beyond 2E12 g/cm^3. This naturally explains the small inner crust impurity inferred from observations of a broad range of systems. The exception are initial compositions with A >= 102 nuclei, where the inner crust remains impure with an impurity parameter of Qimp~20 due to the N = 82 shell closure. In agreement with previous work we find that nuclear heating is relatively robust and independent of initial composition, while cooling via nuclear Urca cycles in the outer crust depends strongly on initial composition. This work forms a basis for future studies of the sensitivity of crust models to nuclear physics and provides profiles of composition for realistic crust models., 25 Pages, accepted for publication in Ap. J

A systematic search for axial octupole deformation in the actinides and superheavy nuclei with proton numbers $Z=88--126$ and neutron numbers from the two-proton drip line up to $N=210$ was performed in covariant density functional theory (DFT) using four state-of-the-art covariant energy density functionals representing different model classes. The nuclei in the $Z\ensuremath{\sim}96, N\ensuremath{\sim}196$ region of octupole deformation were investigated in detail and the systematic uncertainties in the description of their observables were quantified. A similar region of octupole deformation exists also in Skyrme DFT and microscopic+macroscopic approaches but it is centered at somewhat different particle numbers. Theoretical uncertainties in the predictions of the regions of octupole deformation increase on going to superheavy nuclei with $Z\ensuremath{\sim}120, N\ensuremath{\sim}190$. There are no octupole deformed nuclei for $Z=112--126$ in covariant DFT calculations. This agrees with Skyrme DFT calculations, but disagrees with Gogny DFT and microscopic+macroscopic calculations which predict an extended $Z\ensuremath{\sim}120, N\ensuremath{\sim}190$ region of octupole deformation.

In this paper, developed wireless portable infrared pyrometer with dual channel fiber optic is described. The pyrometer measures surface temperature in wide infrared spectral range of 2 - 25 um. A data processing algorithm based on the methods of synchronous detection providing accuracy

A systematic search for extremely deformed structures in the N~Z nuclei of the A~40 mass region has been performed for the first time in the framework of covariant density functional theory. At spin zero such structures are located at high excitation energies which prevents their experimental observation. The rotation acts as a tool to bring these exotic shapes to the yrast line or its vicinity so that their observation could become possible with future generation of $\gamma-$tracking (or similar) detectors such as GRETA and AGATA. The major physical observables of such structures (such as transition quadrupole moments as well as kinematic and dynamic moments of inertia), the underlying single-particle structure and the spins at which they become yrast or near yrast are defined. The search for the fingerprints of clusterization and molecular structures is performed and the configurations with such features are discussed. The best candidates for observation of extremely deformed structures are identified. For several nuclei in this study (such as $^{36}$Ar), the addition of several spin units above currently measured maximum spin of $16\hbar$ will inevitably trigger the transition to hyper- and megadeformed nuclear shapes.

The search for extremely deformed structures in the yrast and near-yrast region of $^{28}$Si has been performed within the cranked relativistic mean field theory up to spin $I=20\hbar$. The fingerprints of clusterization are seen (well pronounced) in the superdeformed (hyperdeformed) configurations., Comment: 3 pages, 2 figures (note that due to size limitations Fig. 2 has reduced resolution as compared with journal submission), contribution to the proceedings of the 11th International conference on Clustering Aspects of Nuclear Structure and Dynamics, Napoli, May 23-27, 2016, which will be published in Journal of Physics: Conference series

The correlations between global description of the ground state properties (binding energies, charge radii) and nuclear matter properties of the state-of-the-art covariant energy density functionals have been studied. It was concluded that the strict enforcement of the constraints on the nuclear matter properties (NMP) defined in Ref.\ \cite{RMF-nm} will not necessary lead to the functionals with good description of the binding energies and other ground and excited state properties. In addition, it will not substantially reduce the uncertainties in the predictions of the binding energies in neutron-rich systems. It turns out that the functionals, which come close to satisfying these NMP constraints, have some problems in the description of existing data. On the other hand, these problems are either absent or much smaller in the functionals which are carefully fitted to finite nuclei but which violate some NMP constraints. This is a consequence of the fact that the properties of finite nuclei are defined not only by nuclear matter properties but also by underlying shell effects. The mismatch of phenomenological content, existing in all modern functionals, related to nuclear matter physics and the physics of finite nuclei could also be responsible., Comment: 14 pages, 9 figures, Physical Review C, in press

A systematic investigation of octupole deformed nuclei is presented for even-even systems with $Z\leq 106$ located between the two-proton and two-neutron drip lines. For this study we use five most up-to-date covariant energy density functionals of different types, with a non-linear meson coupling, with density dependent meson couplings, and with density-dependent zero-range interactions. Pairing correlations are treated within relativistic Hartree-Bogoliubov (RHB) theory based on an effective separable particle-particle interaction of finite range. This allows us to assess theoretical uncertainties within the present covariant models for the prediction of physical observables relevant for octupole deformed nuclei. In addition, a detailed comparison with the predictions of non-relativistic models is performed. A new region of octupole deformation, centered around $Z\sim 98, N\sim 196$ is predicted for the first time. In terms of its size in the $(Z,N)$ plane and the impact of octupole deformation on binding energies this region is similar to the best known region of octupole deformed nuclei centered at $Z\sim 90, N\sim 136$. For the later island of octupole deformed nuclei, the calculations suggest substantial increase of its size as compared with available experimental data., 26 pages, 19 figures, 1 Table, submitted to Physical Review C

The structure of odd–odd nuclei, such as 36Cl, offers a scope for investigating the underlying proton– neutron residual interaction. Such nuclei exhibit highly complex level structures due to the large number of possible couplings of the odd proton and neutron to the even–even core. In the analysis of the experimental data for the 36Cl nucleus, a few new gamma rays was also obtained; they were carefully placed in the level structure using coincidence techniques and relative intensities. The directional correlation from oriented nuclei ratios for the new as well as the known γ-ray transitions was also calculated.

The impact of pairing correlations on the fission barriers is investigated in Relativistic Hartree Bogoliubov (RHB) theory and Relativistic Mean Field (RMF)+BCS calculations. It is concluded that the constant gap approximation in the usual RMF+BCS calculations does not provide an adequate description of the barriers. The RHB calculations show that there is a substantial difference in the predicted barrier heights between zero-range and finite range pairing forces even in the case when the pairing strengths of these two forces are adjusted to the same value of the pairing gap at the ground state., Comment: 9 pages, 8 figures

The rotating nuclei represent one of most interesting subjects for theoretical and experimental studies. They open a new dimension of nuclear landscape, namely, spin direction. Contrary to the majority of nuclear systems, their properties sensitively depend on time-odd mean fields and currents in density functional theories. Moreover, they show a considerable interplay of collective and single-particle degrees of freedom. In this chapter, I discuss the basic features of the description of rotating nuclei in one-dimensional cranking approximation of covariant density functional theory. The successes of this approach to the description of rotating nuclei at low spin in pairing regime and at high spin in unpaired regime in wide range of deformations (from normal to hyperdeformation) are illustrated. I also discuss the recent progress and open questions in our understanding of the role of proton-neutron pairing in rotating nuclei at $N\approx Z$, the physics of band termination and other phenomena in rotating nuclei.

The current status of the application of covariant density functional theory to the description of actinides and superheavy nuclei is reviewed. The achievements and open problems are discussed., Comment: 14 pages, 7 figures, invited talk at the Zakopane Conference on Nuclear Physics "Extremes of the Nuclear Landscape", Zakopane, Poland, August 31 - September 7, 2014

Thin-film Pt/PZT/Ir(Ti/SiO/Si) and Ir/PZT/PTO/Ir(Ti/SiO2/Si) capacitors, as-grown and after ageing, are investigated. A comprehensive study based on the Auger spectroscopy and measurement of electrical and ferroelectrical characteristics is performed. Ageing results in increasing of the oxygen content in PZT, broadening of interfaces owing to formation of metal oxides, diffusion of Pb and Ti towards the top electrode along the grain boundaries, and diffusion of Ti into PZT grain. These processes induce decreasing of the structure capacitance, healing of the interface traps, enhance leakage and dielectric loss.

The impact of collective vibrations on quasiparticle states of open-shell odd-mass nuclei and their possible interference with tensor force is investigated. The inclusion of collective vibrations and their coupling to single-quasiparticle motion improves the description of experimental spectra in such nuclei. We found that the energy splittings of the single-quasiparticle states, which are sensitive at the mean-field level to the tensor part of the effective nucleon-nucleon interaction, are affected by quasiparticle-vibration coupling. Both quasiparticle-vibration coupling and effective tensor interaction act in the same direction. This suggests that effective tensor interaction has to be quenched as compared with previous estimates.

We calculate properties of the ground and excited states of nuclei in the nobelium region for proton and neutron numbers of 92, 43 LaTeX pages, 14 figures, accepted in Nuclear Physics A, Special Issue on Superheavy Elements

The analysis of quasiparticle spectra in heaviest $A\sim 250$ nuclei with spectroscopic data provides an additional constraint for the choice of effective interaction for the description of superheavy nuclei. It strongly suggest that only the parametrizations of the relativistic mean field Lagrangian which predict Z=120 and N=172 as shell closures are reliable for superheavy nuclei. The influence of the central depression in the density distribution of spherical superheavy nuclei on the shell structure is studied. Large central depression produces large shell gaps at Z=120 and N=172. The shell gaps at Z=126 and N=184 are favored by a flat density distribution in the central part of nucleus. It is shown that approximate particle number projection (PNP) by means of the Lipkin-Nogami method removes pairing collapse seen at these gaps in the calculations without PNP.

The analysis of quasi-particle spectra in the heaviest A~250 nuclei with spectroscopic data provides an additional constraint for the choice of effective interaction for the description of superheavy nuclei. It strongly suggests that only the parametrizations which predict Z=120 and N=172 as shell closures are reliable for superheavy nuclei within the relativistic mean field theory. The influence of the central depression in the density distribution of spherical superheavy nuclei on the shell structure is studied. A large central depression produces large shell gaps at Z=120 and N=172. The shell gaps at Z=126 and N=184 are favoured by a flat density distribution in the central part of the nucleus. It is shown that approximate particle number projection (PNP) by means of the Lipkin–Nogami (LN) method removes pairing collapse seen at these gaps in the calculations without PNP.

Three strongly coupled sequences have been established in Te-110,Te-112 up to high spins. They are interpreted in terms of deformed structures built on proton 1-particle-1-hole excitations that reach termination at I similar to 40h. This is the first observation of smooth terminating dipole structures in this mass region. Lifetime measurements have allowed the extraction of experimental B(M 1; 1 -> I - 1) and B(E2; I -> I - 2) reduced transition rates for one of the dipole bands in Te-110. The results support the deformed interpretation. (c) 2006 Elsevier B.V. All rights reserved.

We have studied the effect of optical radiation on the conductivity of a thin film field effect transistor based on a Si-SiO 2 -Pt-PZT-SnO 2− x -Pt multilayer structure. Within an admissible radiation dose, the conducting channel possesses a persistent photoconductivity, with an optical data storage time of at least 10 5 s. Effective channel impedance control by an electric field applied to the thin-film ferroelectric-semiconductor structures is demonstrated. The persistent photoconductivity in the studied multilayer structure may be quenched by only an increase of temperature, for example, using heating by an alternating switching electrical field.

We present pycnonuclear reaction rate calculations for systems involving neutron-rich oxygen, neon and magnesium isotopes. The results are obtained taking into account the screening potential effects and the internuclear many-body correlations. In this work, the S-factor predictions are derived from the one-dimensional barrier penetration model.

A compact cross section data base is obtained for almost 5000 nonresonance nuclear reactions involving stable and unstable Be, B, C, N, O, F, Ne, Na, Mg, and Si isotopes. The calculations are performed using the San Paulo potential and the barrier penetration formalism. The calculated cross sections are approximated by simple analytical formulas. The results are necessary for simulating nuclear burning in neutron stars.

Theoretical calculations of rotating N ≈ Z nuclei with A = 58 − 80 within the cranked Nilsson+Strutinsky approach, cranked relativistic mean field and cranked relativistic Hartree+Bogoliubov theories show good agreement with experiment. They point on the presence of the isovector t = 1 np -pairing, but do not show any indications of the isoscalar t = 0 np -pairing.