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It is now largely accepted that dark matter, and more specifically, Weakly Interacting Massive Particles (WIMPs), constitute the majority of the mass in our Universe. Within this thesis are presented: (i) an overview of the motivation and evidence for the existence of dark matter; (ii) a detailed discussion of direct detection techniques and a worldwide review of WIMP search experiments; and (iii) new experimental measurements and complementary detailed numerical simulations, carried out by the author, to determine the performance of DRIFT experimental technology. Collectively, this work explores the capability of DRIFT technology to detect dark matter, and in doing so, to resolve one of the key open questions of contemporary science. The DRIFT programme consists of an array of direct dark matter search detectors located in the Boulby mine. An important limitation to the experiment is the neutron and gamma-ray background. Experimental work presented here has determined the U and Th content of the cavern rock to be 66±6 ppb and 145±13 ppb respectively, clarifying ambiguities in previous estimations. Through the use of a Monte Carlo simulation the neutron and gamma-ray background experienced by DRIFT has been determined and the experimental implications assessed. In addition, the activity of the main neutron calibration source used to calibrate DRIFT modules has been measured and was found to be 11600 n s−1±5% on the date of exposure, resolving an earlier discrepancy. Analysis of experimental data has confirmed that the technology employed by DRIFT detectors has the capability to provide directional information of recoiling nuclei at the low energies of interest to dark matter searches. A Monte Carlo simulation has then been employed to determine the WIMP-nucleon sensitivity achievable using DRIFT detectors of the present performance, also examining what would be achievable if this was supplemented by a realistic active neutron veto detector. It is found that a CS2-filled DRIFT type detector running at a 500 NIP threshold ( 16 keV and 27 keV for C and S recoils respectively) for 300 kg years, and surrounded by the proposed veto scheme, would expect to observe a background of six un-vetoed events. The minimum positive signal above this background (90% C.L.) would correspond to a WIMP-nucleon sensitivity limit of 1.75×10−9 pb. This identifies the realistic limit of what can be achieved using gaseous CS2 as a target medium. An investigation into the limits achievable using a similar array in which DRIFT modules act as self-vetoing detectors is also examined providing insight into the future development and operation of the DRIFT programme.

<p> Historically, the thermal photon inverse slope parameter has been interpreted as the thermalization temperature of the QGP. Observation of the thermal photon spectrum in nucleus-nucleus collisions at the ALICE and PHENIX experiments obtain the inverse slope parameter, but the obtained values are inconsistent with the thermalization temperature predicted by the hydrodynamic model. It has therefore been argued that the inverse slope parameter is not representative of the true QGP thermalization temperature because not all thermal photons are emitted at thermalization. This research will probe this assertion using an investigation of flow and nuclear suppression of thermal photons from ALICE Pb-Pb collisions at &radic;<i>s_NN</i> = 2.76 TeV and comparison to p-p data at &radic;<i>s_NN</i> = 2.76 TeV.</p>

High angular momentum states in $\sp{79}$Rb were populated via the $\sp{63}$Cu($\sp{19}$F,2pn)$\sp{79}$Rb $\sp{65}$Cu($\sp{18}$O,4n)$\sp{79}$Rb reactions. The 65 MeV $\sp{19}$F and 65 MeV $\sp{18}$O beams were provided by the Florida State University FN Tandem accelerator. Prompt $\gamma$-$\gamma$ coincidences were measured for both reactions. Two additional $\gamma$ cascades have been assigned to $\sp{79}$Rb, including a new high-excitation structure dominated by dipole transitions. Firm spin assignments were made for the first time for a number of states by means of directional correlation ratios and an angular distribution measurement using the $\sp{63}$Cu($\sp{19}$F,2pn) reaction. The Doppler-shift attenuation method was used to determine lifetimes for states and their respective side-feeding times in both the yrast positive-parity and yrast negative-parity states. Transition quadrupole moments were deduced from the transition strengths and compared with those predicted by Woods-Saxon cranking calculations. The energy spacings and mixing ratios were compared with particle-rotor calculations. A recoil distance apparatus has also been developed as part of this project. Software has been written to analyze the results from a $\sp{\rm nat}$Ni($\sp{19}$F,2pn)$\sp{74}$Br reaction. The 62 MeV $\sp{19}$F beam was also provided by the FN Tandem accelerator. Singles events were taken for a number of drift distances. Lifetimes of states in $\sp{74}$Br have been measured and compared with previously known values with excellent agreement. / Source: Dissertation Abstracts International, Volume: 54-12, Section: B, page: 6268. / Major Professor: Samuel L. Tabor. / Thesis (Ph.D.)--The Florida State University, 1993.

High spin states of an odd-proton, an odd-neutron, and an even-even rare-earth nucleus have been investigated using the FN Tandem-Superconducting Linear Accelerator facility at Florida State University. Each $\gamma$-$\gamma$ coincidence experiment was performed using all or part of the Pitt-FSU $\gamma$ array consisting of up to 10 escape suppressed high purity germanium (HPGe) detectors. The nucleus $\sp{177}$Ta was produced with the reaction $\sp{170}$Er($\sp{11}$B,4n) at 55 and 60 MeV. From this experiment, 88 new $\gamma$-rays have been assigned to this nucleus. Investigation of normal deformed identical bands and the $h\sb{9/2}$ bandcrossing anomaly were performed. The nucleus $\sp{175}$Ta was produced using the reaction $\sp{170}$Er($\sp{11}$B,6n) at 80 MeV in a further investigation of the $h\sb{9/2}$ anomaly. High spin states of $\sp{170}$Yb and $\sp{171}$Yb were produced using the reaction $\sp{170}$Er($\alpha,xn$) at 40 MeV and 35 MeV, respectively. These experiments resulted in 67 new $\gamma$-rays being assigned to the even-even nucleus, and 110 new $\gamma$-rays being assigned to the odd-A nucleus. Angular correlations have been measured in the determination of level spins. Configuration assignments are made for the rotational structures in terms of single particle Nilsson states, and a detailed Cranked Shell Model (CSM) analysis has been performed in each case. In addition, Projected Shell Model (PSM) calculations are presented and compared with the experimental data. Transition strength ratios have been measured and compared with theory. / Source: Dissertation Abstracts International, Volume: 57-04, Section: B, page: 2645. / Major Professor: Mark A. Riley. / Thesis (Ph.D.)--The Florida State University, 1996.

Source: Dissertation Abstracts International, Volume: 35-02, Section: B, page: 0724. / Thesis (Ph.D.)--The Florida State University, 1974.

Source: Dissertation Abstracts International, Volume: 35-09, Section: B, page: 4384. / Thesis (Ph.D.)--The Florida State University, 1974.

Source: Dissertation Abstracts International, Volume: 23-05, page: 1756. / Thesis (Ph.D.)--The Florida State University, 1962.

Current scientific experiments are often characterized by massive amounts of very complex data and the need for complex data analysis software. Object-oriented database (OODB) systems have the potential of improving the description of the structure and semantics of this data and of integrating the analysis software with the data. This dissertation results from research to enhance OODB functionality and methodology to support scientific databases (SDBs) and, more specifically, to support a nuclear physics experiments database for the Continuous Electron Beam Accelerator Facility (CEBAF). / This research to date has identified a number of problems related to the practical application of OODB technology to the conceptual design of the CEBAF experiments database and other SDBs: the lack of a generally accepted OODB design methodology, the lack of a standard OODB model, the lack of a clear conceptual level in existing OODB models, and the limited support in existing OODB systems for many common object relationships inherent in SDBs. / To address these problems, the dissertation describes an Object-Relationship Diagram (ORD) and an Object-oriented Database Definition Language (ODDL) that provide tools that allow SDB design and development to proceed systematically and independently of existing OODB systems. These tools define multi-level, conceptual data models for SDB design, which incorporate a simple notation for describing common types of relationships that occur in SDBs. ODDL allows these relationships and other desirable SDB capabilities to be supported by an extended OODB system. / A conceptual model of the CEBAF experiments database is presented in terms of ORDs and the ODDL to demonstrate their functionality and use and provide a foundation for future development of experimental nuclear physics software using an OODB approach. / Source: Dissertation Abstracts International, Volume: 53-03, Section: B, page: 1463. / Major Professor: Gregory A. Riccardi. / Thesis (Ph.D.)--The Florida State University, 1992.