Nuclei in the A~ 180 region were populated and investigated in a series of deep-inelastic reactions involving an 11.4 MeV per nucleon 136Xe beam produced by the GSI UNILAC accelerator, impinging on a selection of tantalum, tungsten and rhenium targets. The reaction products were released from both thermal (TIS) and FEBIAD ion sources and subsequently mass-separated using the GSI on-line mass separator. This work concentrates on the observation of gamma rays associated with the decay of the well known Kpi= 37/2--, t1/2 = 51.4 min. isomer in 177Hf. Due to the anomalous half-life characteristics and unexpectedly high yield of this decay, it is interpreted as being fed via the beta-decay of a high-K isomer in 177Lu. By comparing the experimental findings with the results obtained from multi-quasiparticle blocked-BCS-Nilsson calculations (which predict a low-lying state with Kpi = 39/2-- in 177Lu), the proposed decay is suggested to be an energetically favoured Kpi= 39/2-- five-quasiparticle state in 177Lu. A half-life of 7.7+/-3.0 min. is determined for this previously unreported A = 177 beta-decay path, also involving 89-keV and 1003-keV gamma-ray transitions in association with hafnium X-rays. In addition, two previously unreported transitions (2016 and 2114 keV) were assigned to 182Hf as a result of their coincidence with Hf X-rays and the 98 keV 2+ → 0+ decay of that nucleus.

Optical model studies of low energy (d,d) data show that deuteron-nucleus tensor potentials differ from theoretical model predictions. This suggests that measurement of additional observables, such as Polarization Transfer Coefficients (PTC), are needed to complement the existing data. Whether PTCs can clarify the experimental/theoretical ambiguity has been a matter of controversy. The first part of this thesis addresses this problem. We began by investigating whether the PTC, yields new information concerning the deuteron-nucleus tensor potential. We then examined the extent to which this coefficient can distinguish between the two types of tensor forces, Tr and Tp. We showed that Kyzz is strongly affected by tensor force effects, and that the origin of this sensitivity is the bi-linear combination of scattering amplitudes, Im(Q00Q*21). We also found that, for realistic optical mode parameters, T21 and particularly Kyzz discriminate between the effects of both tensor forces. In the second part of this thesis we study the Weinberg State Expansion model (WSE) for (d,p) reactions. The weakly bound structure of the deuteron suggests the relevance of 3-body effects in the dynamics of deuteron stripping. At intermediate energies, the DWBA provides a much less reliable description of particle transfer reactions. Although the adiabatic theory (ADIA) has provided improvements over the conventional DWBA, recent experimental data suggest that it needs to be refined. The WSE method, in which the dominant contributions from the 3-body channels are explicitly included, is a way to systematically improve ADIA which appears as the lowest order solution in the WSE theory. In implementing the WSE model, we found that as the Weinberg basis size N increases more c.m. n-p relative energies are simulated and readily included into the (d,p) calculations. We also showed that, when performing zero-range WSE calculations for 66Zn(d,p)67Zn (G.S.;5l2-;1 =3) at 25 and 88.2 MeV, the results for dsigma/dO and iT11 converge for N=35. Although 35 Weinberg states were used in constructing the new basis, the reaction calculation reduced to a three coupled channels problem. Our calculations are therefore more efficient than the CDCC methods. The WSE results for dsigma/dO and iT11 were also compared against those of equivalent ADIA and Quasi-ADiabatic (QAD) methods. Our findings reveal that: a) the WSE model provides significant corrections to ADIA's predictions and as such constitutes an elegant mathematical justification of ADIA's ideas; b) the WSE results are overall in good agreement with those obtained using QAD.

The theory of the optical potential for proton scattering at intermediate energies is discussed in detail. The first and second order terms of the KMT multiple scattering optical potentials are calculated for proton scattering from light nuclei in the intermediate energy region (135-300MeV). A momentum space method is developed which allows the study of all the nonlocalities of the potential. A practical numerically stable approximate procedure for the treatment of the Coulomb interaction in momentum space calculations is discussed. The accuracy of the method is compared with other prescriptions in the literature and is shown to produce accurate calculations of scattering observables. The first order term of the KMT optical potential is calculated for proton elastic scattering from 16O and 40Ca. Several approximate treatments of this potential are analysed. In particular it is shown that, using a free nucleon-nucleon transition amplitude with energy fixed at half of the incident beam energy, the optimal factorization provides a good approximation to the full folding potential in the description of the elastic scattering observables. The second order corrections to the KMT optical potential for the elastic scattering of protons from 16o are calculated at 135, 200 and 300 MeV incident energies, paying particular importance to the nonlocalities inherent in the potential. It is shown that these nuclear medium effects result in a significant reduction in the proton-target absorption and modifies the elastic scattering wave function in the interior of the nucleus.

Inelastic scattering of heavy ions to low-lying collective states is studied. Symmetries of the scattering amplitude are discussed and, in particular, the conditions for the validity of an approximate symmetry property are derived. One condition is that the excitation should be 'adiabatic'. The consequences of this approximate symmetry are given: these include zero vector polarization and a gamma-ray distribution that is symmetric about the direction of recoil. In the more general case, and under strong absorption conditions, the full inelastic scattering amplitude is decomposed into components corresponding to waves turning in opposite directions about the scattering centre. It is shown that this allows a simple interpretation of cross-section structure, particularly in the quasi-classical limit, which is derived and explained. The polarization and γ-ray symmetry angle are also discussed in these terms, and conditions of weaker absorption and Coulomb excitation are considered using the same method. A new proof of the asymptotic form of certain Clebsch-Gordan coefficients is given, and a useful property of spherical harmonics derived.

A study is made of polarized deuteron elastic scattering from 58Ni and 40Ca at the intermediate energies of 400 and 700 MeV. A three-body formalism, based on the Single Folding Model, is used for two sets of Dirac nucleon optical potential parameters. Both potentials are designed to fit the proton elastic scattering observables at half the incident deuteron energy. The two potentials give different predictions for the deuteron scattering observables when used in the Schrodinger equation with relativistic kinematics. Good qualitative agreement with the experimental observables is obtained in both cases for deuteron elastic cross-section, vector (Ay) and tensor (Ayy) analyzing power data of the Saclay group. Quantitative discrepancies between theory and data, particularly in Ayy, suggest mechanisms missing from the simple three-body model. To this end, two sources of spin-dependent effects, Pauli-blocking and breakup of the deuteron to spin-singlet intermediate states, are studied. The role of the spin-dependence associated with Pauli-blocking is studied quantitatively for the d-58 Ni system. The magnitude of the momentum-dependent Tp tensor interaction, is shown to pass through a local maximum in the region of 400 MeV incident deuteron energy. Comparison of numerical calculations with the available experimental data at this energy shows the Pauli mechanism not to be responsible for outstanding discrepancies between theory and data. Breakup effects on the elastic amplitude are studied within a two-step calculation, using two separate high energy methods. The first neglects distortion in the initial, final and intermediate states. Use is made of the Adiabatic approximation, which allows closure over the intermediate breakup states. The effect on the elastic amplitude due to breakup to both triplet and singlet intermediate spin states are calculated. The inclusion of spin-singlet breakup in the model has a very large effect on Ayy, compared with that of spin-triplet breakup. This is attributed to a large contribution from a TL-like tensor interaction in the case of singlet breakup, which is negligibly small in the triplet case. Second order breakup effects are also calculated in Glauber theory, using central potentials. Continuum-continuum coupling effects are found to be negligible at intermediate energies, and thus the two-step calculation is adequate. Glauber theory shows, however, that distortion effects are important at these energies, and suggests the need for a more accurate treatment of spin-singlet breakup effects in future calculations.

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This paper is concerned with the design, testing and performance of a coincidence system, the proposed North Texas State College accelerator.

Computational demands are continuously increasing, driven by the growing resource demands of applications. At the era of big-data, big-scale applications, and real-time applications, there is an enormous need for quick processing of big amounts of data. To meet these demands, computer systems have shifted towards multi-core solutions. Technology scaling has allowed the incorporation of even larger numbers of transistors and cores into chips. Nevertheless, area constrains, power consumption limitations, and thermal dissipation limit the ability to design and sustain ever increasing chips. To overpassthese limitations, system designers have turned towards the usage of hardware accelerators. These accelerators can take the form of modules attached to each core of a multi-core system, forming a network on chip of cores with attached accelerators. Another option of hardware accelerators are Graphics Processing Units (GPUs). GPUs can be connected through a host-device model with a general purpose system, and are used to off-load parts of a workload to them. Additionally, accelerators can be functionality dedicated units. They can be part of a chip and the main processor can offload specific workloads to the hardware accelerator unit.In this dissertation we present: (a) a microcoded synchronization mechanism for systems with hardware accelerators that provide distributed shared memory, (b) a Streaming Multiprocessor (SM) allocation policy for single application execution on GPUs, (c) an SM allocation policy for concurrent applications that execute on GPUs, and (d) a framework to map neural network (NN) weights to approximate multiplier accuracy levels. Theaforementioned mechanisms coexist in the resource management domain. Specifically, the methodologies introduce ways to boost system performance by using hardware accelerators. In tandem with improved performance, the methodologies explore and balance trade-offs that the use of hardware accelerators introduce.