We study nuclear high-spin states undergoing the transition to the fully stretched configuration with maximum angular momentum $I_{\max }$ within the space of valence nucleons. To this end, we perform a systematic theoretical analysis of non-fully-stretched $I_{\max }-2$ and $I_{\max }-1$ $f_{7/2}^n$ seniority isomers and $d_{3/2}^{-1}{f}_{7/2}^{n+1}$ intruder states in the $A$∼44 nuclei from the lower-$\mathit{fp}$ shell. We employ two theoretical approaches: (i) the density functional theory based on the cranked self-consistent Skyrme-Hartree-Fock method, and (ii) the nuclear shell model in the full $\mathrm{sdfp}$ configuration space allowing for 1$p$-1$h$ cross-shell excitations. We emphasize the importance of restoration of broken angular momentum symmetry inherently obscuring the mean-field treatment of high-spin states. Overall good agreement with experimental data is obtained.

Very neutron deficient uranium isotopes were produced in fusion evaporation reactions using ${}^{40}\mathrm{Ar}$ ions on ${}^{182}\mathrm{W}$ targets. The gas-filled recoil separator RITU was employed to collect the fusion products and to separate them from the scattered beam and other reaction products. The activities were implanted into a position sensitive silicon detector after passing through a gas-counter system. The isotopes were identified using spatial and time correlations between the implants and the decays. Two $\alpha$-decaying states, with $E_{\alpha }=(8612\pm 9)$ keV and $T_{1/2}=(0.{51}_{-0.10}^{+0.17})$ ms for the ground state and $E_{\alpha }=(10678\pm 17)$ keV and $T_{1/2}=(0.{56}_{-0.14}^{+0.26})$ ms for an isomeric state, were identified in ${}^{218}\mathrm{U}$. In addition, the half-life and $\alpha$-decay energy of ${}^{219}\mathrm{U}$ were measured with improved precision. The measured decay properties deduced for ${}^{218}\mathrm{U}$ suggest that there is no subshell closure at $Z=92$.

Long-range correlations between multiplicities in different rapidity windows in hadron-nucleus collisions are analyzed. After recalling the standard results in the probabilistic model, we study them in the framework of perturbative QCD. Considering interacting BFKL pomerons in the form of fan diagrams coupled to a dilute projectile, analytic estimates are done for very large rapidities. The correlation strength results weakly depending on energy and centrality or nuclear size and generically greater than unity. Finally, we turn to the color glass condensate framework. For a saturated projectile and considering the most feasible experimental situation of forward and backward rapidity windows symmetric around the center-of-mass, the resulting correlation strength turns out to be larger than unity and shows a nonmonotonic behavior with increasing energy, first increasing and then decreasing to a limiting value. Its behavior with increasing centrality or nuclear size depends on the considered rapidity windows.

We estimate the electromagnetic effect of the spectator charge on the momentum spectra of ${\pi }^{+}$ and ${\pi }^{-}$ produced in peripheral Pb+Pb collisions at energies currently available at the CERN Super Proton Synchrotron. We find that the effect is large and results in strongly varying structures in the $x_F$ dependence of the ${\pi }^{+}/{\pi }^{-}$ ratio, especially at low transverse momenta where a deep valley in this ratio is predicted at $x_F~0.15-0.20$. It appears that the effect depends on initial conditions, i.e., on the time of initial pion emission, on the distance between the pion formation zone and the two spectator systems, and on the size of the pion emission source. Thus, it provides new information on the space and time evolution of the nonperturbative pion creation process.

Precision measurements were carried out to test the similarities between the ground states of ${}^{76}\mathrm{Ge}$ and ${}^{76}\mathrm{Se}$. The extent to which these two nuclei can be characterized as consisting of correlated pairs of neutrons in a BCS-like ground state was studied. The pair removal $(p,t)$ reaction was measured at the far forward angle of $3^{°}$. The relative cross sections are consistent (at the 5% level) with the description of these nuclei in terms of a correlated pairing state outside the $N=28$ closed shells with no pairing vibrations. Data were also obtained for ${}^{74}\mathrm{Ge}$ and ${}^{78}\mathrm{Se}$.

The exact solution of the nuclear shell model is used for studying the phase transition from superfluid to normal Fermi-liquid as a function of the pairing strength, excitation energy (or temperature), nuclear spin and the presence of other types of residual interactions. The phase transition in a finite system is seen through the change of properties of individual wave functions.

The possibility that atomic nuclei possess stable, extremely elongated (hyperdeformed) shapes at very high angular momentum is investigated in the light of the most recent experimental results. The crucial role of the Jacobi shape transitions for the population of hyperdeformed states is discussed and emphasized. State-of-the-art mean-field calculations including the most recent parametrization of the liquid-drop energy together with thermal effects and minimization algorithms allowing the spanning of a large deformation space predict the existence of a region of hyperdeformed nuclei in the mass $A\sim 120\text{–}130$: Te, Cs, Xe, I, and Ba isotopes. In agreement with predictions presented in reviews by J. Dudek, K. Pomorski, N. Schunck, and N. Dubray [Eur. Phys. J. A 20, 15 (2003)] and J. Dudek, N. Schunck, and N. Dubray [Acta Phys Pol. B 36, 975 (2005)], our extended calculations predict that only very short hyperdeformed bands composed of a dozen discrete transitions at the most are to be expected–in contrast to the results known for the superdeformed bands. We stress the importance of the experimental research in terms of multiple-$\gamma$ correlation analysis that proved to be very efficient for the superdeformation studies and seems very helpful in the even more difficult search for the discrete transitions in hyperdeformed nuclei.

Angular distributions for the elastic scattering of ${}^8\mathrm{Li}$ on ${}^9\mathrm{Be}$ and the neutron transfer reactions ${}^9\mathrm{Be}$(${}^8\mathrm{Li}$,${}^7\mathrm{Li}$)${}^{10}\mathrm{Be}$ and ${}^9\mathrm{Be}$(${}^8\mathrm{Li}$,${}^9\mathrm{Li}$)${}^8\mathrm{Be}$ were measured with a 27 MeV ${}^8\mathrm{Li}$ radioactive nuclear beam. Spectr- oscopic factors for ${}^8\mathrm{Li}$ $\otimes \mathrm{n}=$ ${}^9\mathrm{Li}$ and ${}^7\mathrm{Li}$ $\otimes \mathrm{n}=$ ${}^8\mathrm{Li}$ bound systems were obtained from the comparison between the experimental differential cross section and finite-range distorted-wave Born approximation calculations with the code FRESCO. The spectroscopic factors obtained were compared to shell model calculations and to other experimental values from (d,p) reactions. Using the present values for the spectroscopic factor, cross sections for the direct neutron-capture reactions ${}^7\mathrm{Li}$(n,γ)${}^8\mathrm{Li}$ and ${}^8\mathrm{Li}$(n,γ)${}^9\mathrm{Li}$ were calculated in the framework of a potential model.

The isotopic composition of molybdenum has been measured with high precision using a thermal ionization mass spectrometer, the linearity of which has been verified by measuring the isotopically-certified reference material for strontium (NIST 987). The abundance sensitivity of the mass spectrometer in the vicinity of the molybdenum ion beams has been carefully examined to ensure the absence of tailing effects. Particular care was given to ensuring that potential isobaric interferences from zirconium and ruthenium did not affect the measurement of the isotopic composition of molybdenum. Gravimetric mixtures of two isotopically enriched isotopes, ${}^{92}\mathrm{Mo}$ and ${}^{98}\mathrm{Mo}$, were analyzed mass spectrometrically to calibrate the mass spectrometer, in order to establish the isotope fractionation of the spectrometer for the molybdenum isotopes. This enabled the “absolute” isotopic composition of molybdenum to be determined. An accurate determination of the isotopic composition is required in order to calculate the atomic weight of molybdenum, which is one of the least accurately known values of all the elements. The absolute isotope abundances (in atom %) of molybdenum measured in this experiment are as follows: ${}^{92}\mathrm{Mo}$$=14.5246\pm 0.0015$; ${}^{94}\mathrm{Mo}$$=9.1514\pm 0.0074$; ${}^{95}\mathrm{Mo}$$=15.8375\pm 0.0098$; ${}^{96}\mathrm{Mo}$$=16.672\pm 0.019$; ${}^{97}\mathrm{Mo}$$=9.5991\pm 0.0073$; ${}^{98}\mathrm{Mo}$$=24.391\pm 0.018$; and ${}^{100}\mathrm{Mo}$$=9.824\pm 0.050$, with uncertainties at the 1s level. These values enable an atomic weight $A_r$(Mo) of $95.9602\pm 0.0023$ (1s) to be calculated, which is slightly higher than the current Standard Atomic Weight $A_r$(Mo) $=95.94\pm 0.02$ and with a much improved uncertainty interval. These “absolute” isotope abundances also enable the Solar System abundances of molybdenum to be calculated for astrophysical purposes. Of particular interest are the Solar System abundances of the two $p$-process nuclides—${}^{92}\mathrm{Mo}$ and ${}^{94}\mathrm{Mo}$, which are present in far greater abundance than $p$-process theory suggests. The Solar System abundances for ${}^{92}\mathrm{Mo}$ and ${}^{94}\mathrm{Mo}$ of $0.364\pm 0.012$ and $0.230\pm 0.008$ respectively, (with respect to silicon $={10}^6$ atoms), are the most accurate values measured to date, and should therefore be adopted in future $p$-process calculations, rather than the existing values of $0.378\pm 0.021$ and $0.236\pm 0.013$, respectively.

The momentum distributions, natural orbits, spectroscopic factors, and quasihole wave functions of the ${}^{12}\mathrm{C}$, ${}^{16}\mathrm{O}$, ${}^{40}\mathrm{Ca}$, ${}^{48}\mathrm{Ca}$, and ${}^{208}\mathrm{Pb}$ doubly closed shell nuclei have been calculated in the framework of the correlated basis function theory, by using the Fermi hypernetted chain resummation techniques. The calculations have been done by using the realistic Argonne $v_8^{\text{'}}$ nucleon-nucleon potential, together with the Urbana IX three-body interaction. Operator dependent correlations, which consider channels up to the tensor ones, have been used. We found noticeable effects produced by the correlations. For high momentum values, the momentum distributions show large enhancements with respect to the independent particle model results. Natural orbit occupation numbers are depleted by about 10% with respect to the independent particle model values. The effects of the correlations on the spectroscopic factors are larger on the most deeply bound states.

The generalized model for the description of the prompt fission neutron spectra and multiplicities at neutron and proton energies up to about 100 MeV is described. The three main emission mechanisms considered are the precompound emission, the pre-scission particle evaporation before the saddle point and at descent to the scission point, and the emission from excited fission fragments. The two-component exciton model is used for the description of the preequilibrium stage of the reaction. The time-dependent statistical model with inclusion of the nuclear friction effects describes particle evaporation starting just after the precompound emission stage and lasting for the duration of the evolution of the compound nucleus toward scission. The fragment mass distribution and fission fragment kinetic and excitation energies are determined from the properties of the composite system at the scission point. The particle spectra from the fission fragments are calculated within the statistical approach. These spectra are then transformed into the laboratory rest frame using the calculated fragment kinetic energies and are averaged over the calculated fragment mass distributions. The model was applied to analyze the prompt fission neutron characteristics in the proton and neutron induced fission of actinide nuclei, and comparisons with the experimental data in ${}^{238}\mathrm{U}$($n,f$), ${}^{238}\mathrm{U}$($p,f$), and ${}^{242}\mathrm{Pu}$($p,f$) reactions are presented.

Mass measurements of ${}^{63,64}\mathrm{Ga}$, ${}^{64,65,66}\mathrm{Ge}$, ${}^{66,67,68}\mathrm{As}$ and ${}^{69}\mathrm{Se}$ performed at the LEBIT facility at the NSCL by Penning trap mass spectrometry are presented. The rare isotopes were produced by fast beam fragmentation and in-flight separation, then converted to a low energy beam using a gas stopping technique. Masses of the $N=Z$ nuclei ${}^{66}\mathrm{As}$ and ${}^{64}\mathrm{Ge}$ have been determined with uncertainties of $\delta \mathrm{m}/\mathrm{m}=5\times {10}^{-7}$ and $6\times {10}^{-8}$, respectively, representing a more than ten-fold improvement in precision over previous measurements. For ${}^{63,64}\mathrm{Ga}$, ${}^{65,66}\mathrm{Ge}$, ${}^{67,68}\mathrm{As}$, and ${}^{69}\mathrm{Se}$ relative mass uncertainties of $\delta \mathrm{m}/\mathrm{m}<5\times {10}^{-8}$ were obtained. ${}^{69}\mathrm{Se}$ is found to be 135 keV more bound than the value listed in the 2003 Atomic Mass Evaluation. Using theoretical Coulomb shift energies in combination with the experimental mass values for ${}^{65,66}\mathrm{Ge}$, ${}^{67}\mathrm{As}$, and ${}^{69}\mathrm{Se}$, masses for ${}^{65}\mathrm{As}$, ${}^{66,67}\mathrm{Se}$, and ${}^{69}\mathrm{Br}$ are predicted with an estimated uncertainty of 100 keV. These mass values, in conjunction with our measurements, were used to calculate improved effective lifetimes of the rp-process waiting point nuclei ${}^{64}\mathrm{Ge}$ and ${}^{68}\mathrm{Se}$. We find that ${}^{64}\mathrm{Ge}$ is less of a waiting point while ${}^{68}\mathrm{Se}$ poses a larger delay in the rp-process than previously thought. The improved mass values in this region were also used to investigate the neutron-proton pairing energy of odd-odd $N=Z$ nuclei.

We analyze α-decays to ground and $2^{+}$ vibrational states in even-even nuclei by using a coupled channels formalism. The α-nucleus interaction is simulated by a double folding procedure using M3Y plus Coulomb two-body forces. Collective excitations are described by vibrations of the nuclear surface. We use a repulsive potential, with one independent parameter, in order to simulate Pauli principle and to adjust the energy of the resonant state to the experimental $Q$-value. The decaying state is identified with the zero nodes resonance inside the resulting pocket-like potential. We have found that the fine structure is very sensitive to the strength of the repulsive core and the vibrational parameter of the α-nucleus potential. A satisfactory agreement with existing experimental data was obtained by using the vibrational strength as a free parameter. It turns out that the inverse of this parameter is proportional to the logarithm of the hindrance factor squared. Based on this fact we have made predictions for 15 vibrational α-emitters.

The equation of state and the properties of matter in the high temperature deconfined phase are analyzed by a quasiparticle approach for $T>1.2T_c$. In order to fix the parameters of our model we employ the lattice QCD data of energy density and pressure. First we consider the pure SU(3) gluon plasma and it turns out that such a system can be described in terms of a gluon condensate and of gluonic quasiparticles whose effective number of degrees of freedom and mass decrease with increasing temperature. Then we analyze QCD with finite quark masses. In this case the numerical lattice data for energy density and pressure can be fitted assuming that the system consists of a mixture of gluon quasiparticles, fermion quasiparticles, boson correlated pairs (corresponding to in-medium mesonic states) and gluon condensate. We find that the effective number of boson degrees of freedom and the in-medium fermion masses decrease with increasing temperature. At $T\approx 1.5T_c$ only the correlated pairs corresponding to the mesonic nonet survive and they completely disappear at $T\approx 2T_c$. The temperature dependence of the velocity of sound of the various quasiparticles, the effects of the breaking of conformal invariance and the thermodynamic consistency are discussed in detail.

We calculate the collisional energy loss suffered by a heavy (charm) quark created at a finite time within a quark-gluon plasma in the classical linear response formalism as in Peigne et al. [J. High Energy Phys. 04 (2006) 011]. We pay close attention to the problem of formulating a suitable current and the isolation of binding and radiative energy loss effects. We find that unrealistic large binding effects arising in previous formulations must be subtracted. The finite time correction is shown to be important only for very short length scales on the order of a Debye length. The overall energy loss is similar in magnitude to the energy loss suffered by a charge created in the asymptotic past. This result has significant implications for the relative contribution to energy loss from collisional and radiative sources and has important ramifications for the “single electron puzzle” at the BNL Relativistic Heavy Ion Collider.

This article provides the complete description of results from the Phase I data set of the Sudbury Neutrino Observatory (SNO). The Phase I data set is based on a 0.65 kiloton-year exposure of ${}^2{\mathrm{H}}_2$O (in the following denoted as ${\mathrm{D}}_2$O) to the solar ${}^8\mathrm{B}$ neutrino flux. Included here are details of the SNO physics and detector model, evaluations of systematic uncertainties, and estimates of backgrounds. Also discussed are SNO's approach to statistical extraction of the signals from the three neutrino reactions (charged current, neutral current, and elastic scattering) and the results of a search for a day-night asymmetry in the ${\nu }_e$ flux. Under the assumption that the ${}^8\mathrm{B}$ spectrum is undistorted, the measurements from this phase yield a solar ${\nu }_e$ flux of $\varphi ({\nu }_e)=1.{76}_{-0.05}^{+0.05}(\mathrm{stat}.){}_{-0.09}^{+0.09}(\mathrm{syst}.)\times {10}^6$ cm${}^{-2}$ s${}^{-1}$ and a non-${\nu }_e$ component of $\varphi ({\nu }_{\mu \tau })=3.{41}_{-0.45}^{+0.45}(\mathrm{stat}.){}_{-0.45}^{+0.48}(\mathrm{syst}.)\times {10}^6$ cm${}^{-2}$ s${}^{-1}$. The sum of these components provides a total flux in excellent agreement with the predictions of standard solar models. The day-night asymmetry in the ${\nu }_e$ flux is found to be $A_e=7.0\pm 4.9(\mathrm{stat}.){}_{-1.2}^{+1.3}\%(\mathrm{syst}.)$, when the asymmetry in the total flux is constrained to be zero.

The low-lying level structure of ${}^{31}\mathrm{Mg}$ has been investigated by the antisymmetrized molecular dynamics (AMD) plus generator coordinate method (GCM) with the Gogny D1S force. It is shown that the $N=20$ magic number is broken and the ground state has a pure neutron 2p3h configuration. The coexistence of many-particle, many-hole states at very low excitation energy is discussed.

The low-lying dipole strength distributions of the odd-mass isotopes ${}^{139}\mathrm{La}$ and ${}^{141}\mathrm{Pr}$ were studied in nuclear resonance fluorescence experiments using bremsstrahlung beams. Excited states were observed at excitation energies up to 4 MeV. Spectroscopic information was obtained on excitation energies, decay widths, decay branching ratios, and transition probabilities. The states belonging to the $[[2^{+}\otimes 3^{-}]\otimes \mathit{particle}/\mathit{hole}]$ coupling were a special focus, and the results are compared with other stable odd-mass nuclei at or near the $N=82$ shell closure.

High spin states of ${}^{137,138}\mathrm{Cs}$ have been studied by measuring $\gamma \text{−}\gamma \text{−}\gamma$ coincidences from the spontaneous fission of ${}^{252}\mathrm{Cf}$ with the LBNL Gammasphere detector array. The high spin level scheme of the $N=83$ neutron-rich Cs ($Z=55$) isotope, ${}^{138}\mathrm{Cs}$, built on the $6^{-}$ isomeric state, has been established for the first time up to a 4626 keV level, assigned (${16}^{+}$). The level scheme of ${}^{137}\mathrm{Cs}$ has been expanded up to a 5495 keV level, assigned ($31/2^{-}$). Spins, parities, and configurations are assigned based on the agreement between experimental level energies and shell model calculations and level systematics. Similarities are observed in the $N=82$ isotones, ${}^{137}\mathrm{Cs}$ and ${}^{135}\mathrm{I}$, up to $17/2^{+}$ as well as in the $N=83$ isotones, ${}^{138}\mathrm{Cs}$ and ${}^{136}\mathrm{I}$, up to ${12}^{-}$. The shell model calculations indicate the important role played by interactions between the excitation of the valence protons outside the $Z=50$ major shell and the $f_{7/2}$ valence neutron outside the $N=82$ major shell.