Дисертації з теми "Heavy ion reaction"
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1
De, Sanctis Jacopo <1977>. "Pattern recognition analysis on heavy ion reaction data." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/851/.
Повний текст джерелаАнотація:
One of the problems in the analysis of nucleus-nucleus collisions is
to get information on the value of the impact parameter b. This work
consists in the application of pattern recognition techniques aimed at
associating values of b to groups of events. To this end, a support vec-
tor machine (SVM) classifier is adopted to analyze multifragmentation
reactions. This method allows to backtracing the values of b through
a particular multidimensional analysis. The SVM classification con-
sists of two main phase. In the first one, known as training phase,
the classifier learns to discriminate the events that are generated by
two different model:Classical Molecular Dynamics (CMD) and Heavy-
Ion Phase-Space Exploration (HIPSE) for the reaction: 58Ni +48 Ca
at 25 AMeV. To check the classification of events in the second one,
known as test phase, what has been learned is tested on new events
generated by the same models. These new results have been com-
pared to the ones obtained through others techniques of backtracing
the impact parameter. Our tests show that, following this approach,
the central collisions and peripheral collisions, for the CMD events,
are always better classified with respect to the classification by the
others techniques of backtracing. We have finally performed the SVM
classification on the experimental data measured by NUCL-EX col-
laboration with CHIMERA apparatus for the previous reaction.
2
Becker, Bruce. "Investigation of heavy ion reaction mechanisms by means of the inclusive 93Nb(12C,7Be) and 93Nb(12C,9Be) reactions." Master's thesis, University of Cape Town, 2002. http://hdl.handle.net/11427/6993.
Повний текст джерелаАнотація:
Includes bibliographical references.Inclusive continuum cross-sections for the reactions 93Nb(12C,7Be) and 93Nb(12C,9Be) were measured at the NAC using a ΔE - E setup. A theoretical light output model which could account for the mass and charge dependance of the NaI E detectors was employed to calibrate the NaI(TI) detectors. The model is outlined and it is shown that the nonlinearity of the detector response is only due to a term which describes the mass-dependance. Investigation of the cross-sections revealed interesting facts about the dominant reaction mechanisms in the interaction of 120 with heavy targets. A theoretical model developed by the Milano group has been very successful in describing the continuum cross-sections of a particles (including 9Be) created in similar reactions of 120 and 160, incident on heavy targets. The analysis shows that the same description of the continuum cross-sections of 7Be and 9Be gives good agreement with the data (with different energy-loss parameters and survival probabilities), although there are discrepancies, especially at the lower incident angles. These small discrepancies may indicate the presence of a multistep direct reaction between the detected fragment and the residual nucleus in the exit channel. The most notable result of the analysis of the data was that the spectra of 7Be and 9Be, previously suspected to be created in a final-state interaction of sBe with the residual nucleus, are well-described by a friction-dissipative breakup mechanism.
3
Lauret, Jérôme. "Importance et évolution de l'énergie collective radiale en fonction de l'énergie d'excitation des systèmes formés au cours de la réaction Au+C à 1 GeV/nucléon." Université Joseph Fourier (Grenoble ; 1971-2015), 1997. http://www.theses.fr/1997GRE10211.
Повний текст джерелаАнотація:
Pour la reaction au + c a 1 gev/nucleon, nous avons mesure les energies transverses des fragments emis et ce, pour diverses energies d'excitation de la source emettrice. Aux grandes energies d'excitation et pour obtenir le profil des energies transverses observee, une expansion radiale uniforme importante des sources emettrices est requise. Les vitesses d'expansion en fonction de la charge emise z sont extraites : elles sont d'autant plus importantes que z est faible et semblent suggerer une energie collective dependante du temps pour le systeme en expansion. Cette energie collective augmente avec l'energie d'excitation et contribue a 61% de l'energie totale deposee initialement. Cette energie collective est emportee principalement par les fragments de charges z2.
4
Wang, Gang. "CORRELATIONS RELATIVE TO THE REACTION PLANE AT THE RELATIVISTIC HEAVY ION COLLIDER BASED ON TRANSVERSE DEFLECTION OF SPECTATOR NEUTRONS." Kent State University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=kent1144770985.
Повний текст джерела
5
Turzo, Ketel. "Study of the 12C+197Au reaction at relativistic energies with the INDRA 4pi multidetector." Phd thesis, Université Claude Bernard - Lyon I, 2002. http://tel.archives-ouvertes.fr/tel-00002954.
Повний текст джерелаАнотація:
L'expérience INDRA@GSI permet d'étudier les mécanismes de la réaction 12C+197Au en cinématique directe par l'utilisation du multidétecteur 4p INDRA et de faisceaux de 12C aux énergies relativistes. La source du spectateur de la cible est determinée pour les protons et les fragments légers, séparement de la source de cascade émettant des particules légeres et d'une source de haute energie émettant des fragments approximativement dans le centre de masse. Les spectres de protons en énergie cinétique sont comparés à des combinaisons du modèle de Cascade Intra-Nucléaire de Liège avec des modèles statistiques. Le scénario privilegié associe un processus de cascade avec une multifragmentation statistique. Les températures de pente des fragments determinées par une combinaison de fonctions de Maxwell-Boltzmann mettent en évidence une dépendance en énergie de faisceau, la centralité de la réaction étant donnée par la multiplicité de particules chargées. Les pions, detectés pour la première fois avec INDRA, et les protons rapides présentent une correlation avec le paramètre d'impact mais non avec la production de fragments.
6
Ataol, Murat Tamer. "Multidimensional Quantum Tunnelling Formulation Of Oxygen-16 And Uranium-238 Reaction." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/2/12605031/index.pdf.
Повний текст джерелаАнотація:
Multidimensional quantum tunnelling is an important tool that is used in many areas of physics and chemistry. Sub-barrier fusion reactions of heavy-ions are governed by quantum tunnelling. However, the complexity of the structures of
heavy-ions does not allow us to use simple one-dimensional tunnelling equations to and the tunnelling probabilities. Instead of this one should consider all the degrees of freedom which affect the phenomenon and accordingly the intrinsic
structure or the deformation of the nuclei must be taken into account in the modelling of heavy-ion fusion. These extra degrees of freedom result in a coupling potential term in the Schrodinger equation of the fusing system. In this thesis
16O + 238 U system is considered. Only the rotational deformation of Uranium is assumed and the coupling potential term is calculated for this system by using two diffrent potential types, namely the Woods-Saxon potential and the double folding potential. Using this term in the Schrodinger equation fusion probability and theoretical cross section are calculated. A discussion that addresses then necessity of multidimensional formulation is given. Besides this point the effects of the choice of the potential type are shown.
7
Danley, Tyler. "Measurement of Elliptic Flow Coefficients and Derivation of Reaction Plane Dependent Efficiency of Isolated Photons and ϖ0 in Center-of-Mass Pair Energy 200 GeV Au+Au Collisions at RHIC-PHENIX". Ohio University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1416500118.
Повний текст джерела
8
Kuznetsova, Inga Vladimirovna. "Particle Production in Matter at Extreme Conditions." Diss., The University of Arizona, 2009. http://hdl.handle.net/10150/193745.
Повний текст джерелаАнотація:
We study particle production and its density evolution and equilibration in hot dense medium, such as hadronic gas after quark gluon plasma hadronization and relativistic electron positron photon plasma. For this study we use kinetic momentum integrated equations for particles density evolution with Lorentz invariant reaction rates. We extend these equations, used before for two-to-two particles reactions (1 + 2 ↔ 3 + 4), to the case of two-to-one and backward reactions (1 + 2 ↔ 3). One type of hot dense medium, which we study, is hadronic gas produced at quark gluon plasma hadronization in heavy ions collisions in SPS, RHIC and LHC experiments. We study hadron production at quark gluon plasma hadronization and their evolution in thermal hadronic gas phase. We consider non-equilibrium hadronization model, for which the yields of the light quark hadrons are defined by entropy conservation. Yields of hadrons containing heavier (strange, charm, bottom) quarks are mainly controlled by flavor conservation. We predict yields of charm and bottom hadrons within this non-equilibrium statistical hadronization model. Then we use this non-equilibrium hadronization as the initial condition in the study of hadronic kinetic phase. During this time period some hadronic resonances can be produced in lighter hadrons fusion. This reaction is opposite to resonance decay. Production of resonances is dominant over decay if there is non-equilibrium excess of decay products. Within this model we explain apparently contradictory experimental results reported in RHIC experiments: ∑(1385) yield is enhanced while ∧(1520) yield is suppressed compared to the statistical hadronization model expectation obtained without kinetic phase. We also predict Δ(1232) enhancement. The second type of plasma medium we consider is the relativistic electron position photon plasma (EP³) drop. This plasma is expected to be produced in decay of supercritical field created in ultrashort laser pulse. We study at what conditions this plasma drop is opaque for photons and therefore may reach thermal and chemical equilibrium. Further we consider muon and pion production in this plasma also as a diagnostic tool. Such heavy particles can be diagnostic tool to study the properties of EP³ plasma, similar to the role taken by heavy hadrons production in heavy ions collisions. Finally all these theoretical developments can be applied to begin a study of particles evolution in early universe in temperatures domain from QGP hadronization (160 MeV) to nucleosynthesis (0.1 MeV). The first results on pion equilibration are presented here.
9
Liatard, Éric. "Mesures de sections efficaces totales de réaction avec des faisceaux d'ions lourds stables et radioactifs par la méthode du rayonnement associé." Grenoble 1, 1989. http://www.theses.fr/1989GRE10143.
Повний текст джерелаАнотація:
Nous avons mis au point une nouvelle methode de mesure directe de sections efficaces totales de reaction fondee sur l'utilisation d'un detecteur 4 pi modulaire. Dans un premier temps, des mesures ont ete effectuees avec des faisceaux d'ions lourds delivres par les accelerateurs sara et ganil dans la gamme d'energie 30-80 mev/u. Nous avons ensuite adapte notre dispositif aux mesures avec des faisceaux secondaires radioactifs (ligne lise du ganil). Les resultats obtenus couvrent une large gamme de projectiles legers comprenant des isotopes exotiques situes a la limite de la stabilite vis-a-vis de l'emission de neutrons. A partir des sections efficaces totales de reaction, les rayons carres moyens de ces projectiles sont calcules a l'aide d'un formalisme microscopique simple dont la validite est demontree par les resultats obtenus avec des faisceaux stables. Malgre la presence d'effets de structure marques (n pair- n impair), l'ensemble des isotopes etudies presente un rayon carre moyen normal excepte le #1#1be, le #1#4be et le #1#7b. Enfin, en utilisant les resultats de recents calculs haartree-fock, il est possible de determiner, a partir de nos donnees experimentales, les rayons carres moyens des distributions de neutrons des projectiles de n pairs. Ces rayons se comparent favorablement aux valeurs theoriques issues du meme calcul hartree-fock, excepte pour les cas ou l'extension spatiale des neutrons est tres importante (#1#4be et #1#7b)
10
Hashim, Hasnita. "Heavy ion transfer reactions." Thesis, University of Oxford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306004.
Повний текст джерела
11
MacMillar, Susanna. "Isotopes as Mechanism Spies : Nucleophilic Bimolecular Substitution and Monoamine Oxidase B Catalysed Amine Oxidation Probed with Heavy Atom Kinetic Isotope Effects." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis (AUU), 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7441.
Повний текст джерела
12
Charvet, Michael. "Recherche de l'apparition du phénomène de multifragmentation dans le système 32S+27Al." Université Joseph Fourier (Grenoble), 1997. http://www.theses.fr/1997GRE10065.
Повний текст джерелаАнотація:
Le sujet de recherche presente dans ce memoire concerne la physique des ions lourds aux energies intermediaires, et plus precisement l'analyse du mode de desexcitation des systemes composites formes dans les collisions noyau-noyau. L'etude des noyaux chauds a mis en evidence la correlation qu'il existe entre l'energie deposee dans un systeme et son mode de desexcitation. Ainsi, a basse energie, les phenomene d'evaporation (emission de particules legeres de charge un ou deux) et d'emission binaire sequentielle (dont l'evaporation est un cas particulier) gouvernent le mode de desexcitation du systeme cree en voie de sortie. Lorsque l'energie croit, on observe l'apparition simultanee de fragments, dits de masse intermediaire (imf), dont la charge est superieure ou egale a trois. Ce phenomene, appele multifragmentation, fait aujourd'hui l'objet de nombreuses etudes car il pourrait refleter l'existence d'une transition de phase dans la matiere nucleaire. Ce travail s'inscrit dans le cadre d'une recherche du seuil d'apparition de ce phenomene. Pour ce faire, differentes experiences sur le systeme #3#2s+#2#7al ont ete realisees a l'aide du multidetecteur amphora, dans une gamme d'energie comprise entre 24,5 et 37,5 mev/nucleon. L'analyse des donnees, qui a largement fait appel aux techniques d'analyse multidimensionnelle developpees par le groupe (ces techniques permettant d'optimiser l'accord entre l'experience et la simulation), a permis de mettre en evidence un changement de mecanisme de desexcitation du systeme composite cree dans les collisions les plus centrales. A 24,5 mev/nucleon, les donnees sont compatibles avec un processus de desexcitation binaire sequentielle ; au dela, elles sont compatibles avec un processus de type multifragmentif, a ceci pres que l'on observe, experimentalement, un surplus d'energie cinetique pour les fragments. Ce surplus d'energie, incompatible avec un mecanisme purement thermique peut s'expliquer par la presence d'energie d'expansion dans nos echantillons. L'energie radiale extraite de nos donnees croit avec l'energie de bombardement : de 0 mev/nucleon a 24,5 mev/nucleon jusqu'a 0,8 mev/nucleon pour la plus grande energie faisceau.
13
Lo, Monaco L. "Nucleon transfer in heavy ion reactions." Thesis, University of Oxford, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.371555.
Повний текст джерела
14
Gilday, A. J. "Semiclassical theory of heavy ion fusion reactions." Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376923.
Повний текст джерела
15
Chabane, Amar. "Multifragmentation explosive dans la réaction 32S+27Al à 37. 5 MeV/nucléon." Université Joseph Fourier (Grenoble), 1995. http://www.theses.fr/1995GRE10057.
Повний текст джерелаАнотація:
L'etude des evenements complets dans la reaction #3#2s + #2#7al a permis de mettre en evidence un phenomene de multifragmentation du noyau compose residuel forme lors de la fusion du systeme cible-projectile pour des collisions centrales. La theorie de la percolation, idee novatrice en physique nucleaire, permet de montrer que nous sommes surcritique au sens de la percolation mais ne permet pas de conclure quand a un eventuel changement de phase dans la matiere nucleaire. Cette etude montre aussi, que les donnees experimentales sont incompatibles avec un code de simulation binaire sequentiel reconnu (gemini). Par contre, la comparaison avec un code de multifragmentation statistique (code de berlin) montre que les donnees sont bien representative d'une multifragmentation du noyau bien qu'au niveau energetique l'accord ne soit plus satisfaisant ; notamment les vitesses relatives entre fragments de masses intermediaires sont plus grandes dans le cas de l'experience ainsi que l'impulsion du fragment le plus lourd qui ne peut etre reproduite. L'etude des partitions en charges dans le cadre de l'ensemble boltzmann canonique met en evidence une thermalisation du noyau compose, avec emission de particules de preequilibre. La temperature deduite est d'environ 5 mev et le volume de freeze-out de l'ordre de 2. 3 fois le volume normal. Les variables dynamiques sont bien reproduites par un code simulant une desintegration explosive du noyau suite a la decompression de celui-ci. Cette energie radiale resulte du phenomene d'onde de choc qui apparait lorsque la vitesse de propagation de l'onde est superieure a celle du son dans la matiere nucleaire. La mesure de ce seuil permettrait de remonter au coefficient d'incompressibilite de la matiere k
16
Windham, Gordon. "Spin dependence in heavy ion induced nuclear reactions." Thesis, University of Surrey, 1986. http://epubs.surrey.ac.uk/843452/.
Повний текст джерелаАнотація:
The interest of this work is to explore the spin dependent effects of projectile structure in nuclear heavy ion induced reactions. The projectiles are considered to consist of two clusters which remain inert, the intercluster wavefunctions are obtained by the use of the orthogonality condition model. Excitation to the low lying projectile states is included by the use of coupled channels calculations. The projectile excited states are included by allowing excitation in the inter cluster wavefunctions. Coupling to the excited states is performed by multipole terms arising from a single folding model, which is used consistently throughout the work. The effects of projectile excitation are considered in two areas, elastic and inelastic scattering, and transfer reactions. It is found that the inclusion of the projectile excited states has a very strong effect on the spin dependent elastic observables, in particular the vector analysing powers. In contrast to earlier analysis it is found that projectile excitation plays a dominant role in reproducing the experimentally observed vector analysing powers for the elastic scattering of 6Li from 16O and 28Si at 22.8 MeV. Projectile excitation is also seen to produce strong spin dependent effects in the elastic scattering of Li from 120Sn at 44 MeV and of 19Ffrom 28Si at 60 MeV. The inclusion of projectile excitation via CCBA calculations produces changes in the transfer cross section for the 28Si (19F, 16O)31P(1/2+ ,g.s.) reaction. The observed changes can be understood in terms of the effects of spin dependence in the reaction path. The inclusion of projectile excitation however does not significantly improve the quality of the agreement with experimental data.
17
Evans, Philip Mark. "Fully relaxed heavy ion reactions in the mass 80 region." Thesis, University of Oxford, 1988. http://ora.ox.ac.uk/objects/uuid:3d0dc2d3-81a3-4842-a914-183c76dc4885.
Повний текст джерелаАнотація:
This thesis describes a set of experiments to investigate the properties of fully relaxed reactions in the mass 80 region. Symmetric and asymmetric entrance channels, leading to similar compound nuclei, have been compared in order to determine the characteristics of the reaction mechanism. The symmetric system 40Ca + 40Ca has been studied at laboratory energies of 197.3 and 230.5 MeV. The fissionlike products were detected by a series of six time of flight telescopes, placed at angles between 10° and 52.4° to the beam, and a Bragg curve spectrometer-multiwire proportional chamber telescope, situated at 30°. Data were collected in both singles and coincidence modes. To complement this measurement, fully damped yields from 28Si + 50,52,54 Cr at 130 MeV and from 28Si + 50Cr at 150 MeV were measured using an array of four avalanche counter-silicon surface barrier detector telescopes spanning the angular range between 20° and 50°. The avalanche counters used in this experiment are of a new design which was developed in Oxford. We present the features of this design and discuss the detectors' operational characteristics. Several possible interpretations of the data are considered. It is shown that diffusion models of deep-inelastic scattering tend to underpredict the measured fully relaxed cross sections. Rotating finite range model calculations of fission barriers point to the possibility of fast-fission in this mass region; a process hitherto associated with much heavier systems. Furthermore, such models also predict that these systems may fission asymmetrically. The more commonly employed rotating liquid drop model of the nucleus is unable to predict either of these effects. The data are compared with those reported in the literature for other systems in this mass region. It is argued that all these results are consistent with fast-fission and asymmetric fission, thus obviating the need for the previously proposed interpretation in terms of intermediate mechanisms.
18
Barton, Robert Allan. "Multi-strange hyperon production in relativistic heavy -ion collisions." Thesis, University of Birmingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367744.
Повний текст джерела
19
Bauge, Eric. "Collisions d'ions lourds aux énergies intermédiaires : étude de la dynamique d'émission des particules chargées et caractérisation des émetteurs." Université Joseph Fourier (Grenoble ; 1971-2015), 1994. http://www.theses.fr/1994GRE10086.
Повний текст джерелаАнотація:
Lors des collisions d'ions lourds aux energies intermediaires, une large gamme de processus de reaction est mise en jeu ; depuis des processus suffisamment lents pour qu'un equilibre soit atteint a chaque emission de particule, jusqu'a des processus directs, pour lesquels les diffusions nulceon-nucleon et le remplissage de l'espace de phase sont les effets dominants. Pour investiguer cette transition, nous avons etudie, a l'aide de mesures realisees dans le multidetecteur amphora et de simulations, a la fois la dynamique de desexcitation du systeme par emission de particules legeres, et les caracteristiques de l'emetteur de ces particules, ceci pour les systemes 7, 17, 27 et 34 amev, 40ar+al, 40ar+cu et 40ar+ag. Tout d'abord nous evaluons, pour ces systemes, le transfert d'impulsion lineaire des collisions les plus centrales en mesurant la vitesse des residus. Ensuite, en mesurant la fonction de correlation en angle azimutal de paires de particules legeres et en les comparant aux predictions d'un modele statistique nous evaluons le moment angulaire moyen de l'emetteur. Pour etudier la dynamique d'emission, nous comparons les resultats de simulations basees sur un modele de trajectoires classiques avec les fonctions de correlation experimentales en angle azimutal ou en impulsion relative. Enfin, nous examinons les predictions d'un modele buu avance pour le systeme 34amev 40ar+al
20
Cresswell, Alan James. "Studies of nuclear structure using heavy ion-induced transfer reactions." Thesis, University of Liverpool, 1994. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240215.
Повний текст джерела
21
Benatar, Marco. "Nucleon transfer from heavy-ion reactions using the AFRODITE gamma-ray spectrometer." Doctoral thesis, University of Cape Town, 2005. http://hdl.handle.net/11427/6526.
Повний текст джерелаАнотація:
Includes bibliographical references (p. [102]-109).The 1- radiation following the interactions of 1271 on 197 Au and 194Pt at ELAB = 730 MeV has been studied. The beam energy is approximately 9.5% above the Coulomb barrier. The aim of the present work is to study multi-nucleon transfer to and from the target. At energies above the Coulomb barrier, stripping and pickup reactions occur, quasi-elastic and deep-inelastic events dominate, with the target-like and projectile-like fragments remaining in contact over a sufficient period of time for degree of mass and NIZ ratio equilibration to occur. Relative intensities of various target-like fragments as well as projectile-like fragments have been extracted using the RADWARE and GRAZING program respectively. The spectroscopy of the fragments has been investigated by 1-1 coincidence techniques using the AFRODITE Spectrometer from the iThemba Laboratories. Isotopes of Au and Pt have been observed as well as other nuclei having lost or gained one to two protons in the process. Q-values are also calculated and plotted versus the relative intensities. The results of these plots are compared with the predictions of the GRAZING program. The aim of the present work is to determine whether the unpaired proton from both the projectile and the target influences the transfer of nucleons and whether the transfer is done in purely statistical way or again if the unpaired proton does playa part in the transfer. It was found that for both 1271 on 197 Au and 194Pt at ELAB = 730 MeV, the maximum number of transferred nucleons was only 4- and that the predictions from the GRAZING program do not agree with the extracted relative intensities from RADWARE.
22
Alshammari, Suliman. "Flowing afterglow studies of recombination of electrons with heavy Ions using FALP-MS." Thesis, Rennes 1, 2018. http://www.theses.fr/2018REN1S013/document.
Повний текст джерелаАнотація:
La recombinaison dissociative (RD) est le processus dans lequel un ion moléculaire positif se recombine avec un électron et se dissocie après en fragments neutres. Parmi les différents types de réactions entre ions moléculaires et électrons, la RD mérite une attention particulière à cause du rôle important qu'elle joue dans les plasmas à basse température et de faible densité, telles que celles rencontrées dans les ionosphères planétaires et les nuages interstellaires. En dépit de l'apparente simplicité de la RD, son étude s'est avéré difficile aussi bien du point de vue expérimental que théorique. Afin d'apporter plus de lumière sur ce processus, la technique de la post-décharge en écoulement a été introduite et a été largement utilisée ces dernières décennies. La présente thèse est dédiée aux études expérimentales de la réaction RD, à l'aide du spectromètre de masse à sonde Langmuir (FALP-MS) en post-décharge en écoulement, à l'Université de Rennes 1, à Rennes, en France. Nous avons étudié la réaction RD à température ambiante a été étudiée pour les ions moléculaires d'acétone ( ) et les cations de diméthylamine cations ( ainsi que les vitesses de réaction des cations de triméthylamine ( cations, et nous avons obtenu des valeurs avec des incertitudes de of ± 30 %. De plus, nous avons étudié l'attachement électronique à la diméthylamine neutre et nous avons trouvé une constante de vitesse de = 4.81 x 10-10 cm3 s-1. Un nouveau système d'injection pour l'anneau de stockage électrostatique de KACST a été conçu et construit dans le laboratoire de l'IPR à Rennes. Le couplage de la source d'ions avec un analyseur de masse quadripolaire et l'utilisation d'un système de vannes pulsées assurant un pompage différentiel entre différentes régions de la ligne d'injection constitue une méthode nouvelle dans le contexte d'un anneau de stockage. Le but final de ce projet est l'étude des réactions à ions lourds tels que les ions moléculaires biologiquesDissociative recombination (DR) is a process in which a positive molecular ion recombines with an electron and subsequently dissociates into neutral fragments. Among the different types of molecular ion-electron reactions DR deserves particular attention due to the important role it plays in low-temperature and low-density plasmas such as those encountered in planetary ionospheres and interstellar clouds. Despite the apparent simplicity of the DR reaction, its investigation has proven to be a difficult task from both experimental and theoretical perspectives. In order to shed more light upon this process the flowing afterglow technique has been introduced and utilised extensively for the last few decades. This thesis is devoted to experimental studies into the DR reaction using the flowing afterglow Langmuir probe mass spectrometer FALP-MS at the University of Rennes 1, in Rennes, France. The DR reaction at room temperature has been investigated for the acetone molecular ions ( ) and dimethylamine cations ( as well as the reaction rates of trimethylamine ( cations, and the obtained values were with uncertainties of ± 30 %. In addition, the electronic attachment to neutral dimethylamine was also studied and the rate constant was determined to be = 4.81 x 10-10 cm3 s-1. A new ion injection system system for the KACST electrostatic storage ring has been designed and built in the IPR laboratory in Rennes. The coupling of an ion source with a quadrupole mass analyzer and the use of a gas pulsing system to maintain the differential pumping between different regions of the injection line, is a novel technique for use with a storage ring. The final goal of this system is to study the reactivity of heavy ions such as biological molecular ions
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Bauer, W., Burkhard Kämpfer, S. Wolf, and Hanns-Werner Barz. "Analysis of hard two-photon correlations measured in heavy-ion reactions at intermediate energies." Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-31848.
Повний текст джерелаАнотація:
Analysis of hard two-photon correlations measured in heavy-ion reactions at intermediate energies H.W.Barz1,2, B.Kämpfer1,2, GY. Wolf3,4, W. Bauer5 1Institut für Kern- und Hadronenphysik, FZ Rossendorf, PF 510119, 01314 Dresden, Germany 1Institut für Theoretische Physik, TU Dresden, Momrnsenstr. 13, 01062 Dresden, Germany 3GSI Darmstadt, PF 110552, 64220 Darmstadt, Germany 4KFKI RMKI Budapest, POB. 49, H-1525 Budapest, Hungary MSU Michigan, East Lansing, MI 48824, USA Abstract Recently reported measurements of hard photon correlations in the reactions 36Ar On 27Al at 95 A*MeV, 86Kr on natNi at 60 A*MeV, and 181Ta on 197Au at 39.5 A*MeV are analyzed. A Boltzmann-Ühling-Uhlenbeck transport model is used to describe the photon production by individual nucleon-nucleon collisions. In the lighter systems we find the best agreement with data when taking into account only the photons from first chance collisions of nucleons or photons produced during the Passage of the nuclei, while the model predicts also a considerable late-time emission of photons which leads to a depletion of the calculated correlation function. The accuracy of the present data daas not allow firm conclusions on the reliability of this late time evolution. Our inveatigatiions do not support a recently reported interference pattern in the heavy Ta + Au system.
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Bauer, W., Burkhard Kämpfer, S. Wolf, and Hanns-Werner Barz. "Analysis of hard two-photon correlations measured in heavy-ion reactions at intermediate energies." Forschungszentrum Rossendorf, 1995. https://hzdr.qucosa.de/id/qucosa%3A22011.
Повний текст джерелаАнотація:
Analysis of hard two-photon correlations measured in heavy-ion reactions at intermediate energies H.W.Barz1,2, B.Kämpfer1,2, GY. Wolf3,4, W. Bauer5 1Institut für Kern- und Hadronenphysik, FZ Rossendorf, PF 510119, 01314 Dresden, Germany 1Institut für Theoretische Physik, TU Dresden, Momrnsenstr. 13, 01062 Dresden, Germany 3GSI Darmstadt, PF 110552, 64220 Darmstadt, Germany 4KFKI RMKI Budapest, POB. 49, H-1525 Budapest, Hungary MSU Michigan, East Lansing, MI 48824, USA Abstract Recently reported measurements of hard photon correlations in the reactions 36Ar On 27Al at 95 A*MeV, 86Kr on natNi at 60 A*MeV, and 181Ta on 197Au at 39.5 A*MeV are analyzed. A Boltzmann-Ühling-Uhlenbeck transport model is used to describe the photon production by individual nucleon-nucleon collisions. In the lighter systems we find the best agreement with data when taking into account only the photons from first chance collisions of nucleons or photons produced during the Passage of the nuclei, while the model predicts also a considerable late-time emission of photons which leads to a depletion of the calculated correlation function. The accuracy of the present data daas not allow firm conclusions on the reliability of this late time evolution. Our inveatigatiions do not support a recently reported interference pattern in the heavy Ta + Au system.
25
Lotay, Gavin James. "Gamma-ray spectroscopy measurements for nuclear reactions in novae." Thesis, University of Edinburgh, 2009. http://hdl.handle.net/1842/3893.
Повний текст джерелаАнотація:
The 23Mg(pγ)24Al and 26Al(pγ)27Si astrophysical reactions are expected to be of considerable importance in the nucleosynthesis of A≥20 nuclei in classical novae. Previous studies have indicated that both reactions are dominated by resonant capture to excited states, above the proton-emission thresholds, in the proton-rich nuclei 24Al and 27Si, respectively. Consequently, by determining the nuclear properties of such resonant states it is possible to estimate the 23Mg(pγ)24Al and 26Al(pγ)27Si stellar reaction rates. In this thesis work, excited states in 24Al and 27Si were populated via the 10B(16O, 2n) and 12C(16O, n) heavy-ion fusion-evaporation reactions, respectively. The beams of 16O ions were produced by the Argonne Tandem Linear Accelerator System and prompt electromagnetic radiation was detected using the GAMMASPHERE detector array, which, in the case of the 24Al experiment, was used in coincidence with recoil selection provided by the Argonne Fragment Mass Analyzer. The two γray spectroscopy studies performed in this work allowed level structure determinations below the respective proton-emission thresholds of 24Al and 27Si nuclei, with improved precision on previous work. In addition to this, these studies also allowed a determination of the nuclear properties of proton-unbound astrophysically important γ decaying states, which, in turn, were used to re-evaluate the 23Mg(pγ)24Al and 26Al(pγ)27Si stellar reaction rates. The improved precision of the level energies and unambiguous assignments of resonant states has reduced the relative uncertainties in both the 23Mg(pγ)24Al and 26Al(pγ)27Si stellar reaction rates, constraining the production of A≥20 nuclei in classical novae.
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Wilkinson, H. L. "A study of simple nucleon transfer reactions between heavy ions and '1'9'7Au." Thesis, University of Manchester, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383930.
Повний текст джерела
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Timmers, Heiko, and H. Timmers@adfa edu au. "Expressions of Inner Freedom." The Australian National University. Research School of Physical Sciences and Engineering, 1996. http://thesis.anu.edu.au./public/adt-ANU20020328.152158.
Повний текст джерелаАнотація:
This study investigates the fusion and scattering of nuclei at energies spanning the Coulomb barrier. The coupling of the relative motion of the nuclei to internal degrees of freedom can be thought to give rise to a distribution of potential barriers.
¶
Two new methods to extract representations of these potential barrier distributions are suggested using the eigen-channel model. The new techniques are based on measurements of quasi-elastic and elastic backscattering excitation functions, from which the representations are extracted by differentiation. A third method utilizing transfer excitation functions is introduced using qualitative arguments. The techniques are investigated experimentally for the reactions 16O + 92Zr, 144,154Sm, 186W and 208Pb. The results are compared with barrier distribution representations obtained from fusion data. The methods are further explored using the systems 40Ca + 90,96Zr and 32S + 208Pb, for which scattering and fusion excitation functions have been measured. The new barrier distribution representations are consistent with the one from fusion. They are direct evidence of the effects of the internal degrees of freedom on channels other than the fusion channel.
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The new representations are, however, less sensitive to the barrier distribution compared to their fusion counterpart. This observation is investigated using coupled-channels calculations. They suggest that residual weak reaction channels, which are not included in the coupling matrix, are responsible for the reduction in sensitivity. In the case of quasi-elastic scattering a distortion of the barrier structure above the average barrier is observed. This effect appears to be due to the de-phasing of the scattering amplitudes contributing to each eigen-channel. Using the heaviest system, 32S + 208Pb, it is demonstrated that there is no improvement in sensitivity to the barrier distribution for systems with large Sommerfeld parameters. This suggests that diffraction effects are not likely to be the cause of the sensitivity reduction.
¶
The new techniques may be employed successfully in systems with pronounced barrier structure below the average barrier. This is the case for the reactions 40Ca + 90,96Zr. It is shown that for these systems the quasi-elastic scattering and the fusion representations of the barrier distribution contain the same information. The extracted barrier distributions for the two reactions are distinctively different. They are compared to assess the relative importance of collective excitations and neutron transfer in fusion. Exact coupled-channels calculations show that the distribution for 40Ca + 90Zr arises from coupling of the relative motion to double phonon excitations of 90Zr. Further calculations suggest that the reaction 40Ca + 96Zr involves additional coupling to sequential neutron transfer, which is proposed to be a precursor of neutron-neck formation.
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Double phonon excitations are also seen to be important in the system 32S + 208Pb, for which the barrier distribution representations show in addition signatures of one and two neutron transfer.
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Boztosun, Ismail. "Coupled-channels calculations for the scattering of deformed light heavy-ions : a challenge to the standard approach." Thesis, University of Oxford, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325373.
Повний текст джерела
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Lee, R. J. S. "Ion-atom collisions at relativistic and non-relativistic energies." Thesis, Queen's University Belfast, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368591.
Повний текст джерела
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Silva, Nelson Canzian da. "Produção de fragmentos ricos em nêutrons através da fragmentação do 28Si com momento de Plab=14.6 GeV/c por nucleon." Universidade de São Paulo, 1994. http://www.teses.usp.br/teses/disponiveis/43/43131/tde-16122013-155237/.
Повний текст джерелаАнотація:
Foi investigada a produção de isótopos ricos em nêutrons a partir do decaimento de projéteis de \'ANTPOT.28 Si\' com momento de \'P IND.lab\'= 14.6 GeV/c por nucleon seguindo a excitação eletromagnética por alvos de Al, Cu, Sn e Pb. A busca foi feita selecionando fragmentos ricos em nêutrons (\'ANTPOT.6 He\', \'ANTPOT.8 He\',\'ANTPOT.8 Li\', \'ANTPOT.9 Li\', \'ANTPOT.10 Be\', \'ANTPOT.11 Be\' e \'ANTPOT.13 B\') detectados no espectrômetro do Experimento 814 do AGS de Brookhaven. Foi estabelecido um limite superior de 54 ub (a um Nível de Confiança de 95%) para a seção de choque de dissociação eletromagnética para um único canal, baseado num conjunto com ~3x \'10 POT.7\' partículas de feixe. Foram medidas seções de choque de produção de isótopos ricos em nêutrons por fragmentação nuclear e obtidas as distribuições de energia transversal e energia a zero graus associadas à produção destes fragmentos. As distribuições de momento transversal para o \'ANTPOT.6 He\' e para o \'ANTPOT.9 Li\' foram medidas experimentalmente e os resultados comparados ao modelo estatístico de Goldhaber para a fragmentação. A comparação fornece um valor médio de 229±9 MeV/c para o momento de Fermi do projétil.The production of neutron-rich isotopes from the decay of 28Si projectile at Plab = 14.6 GeV/c per nucleon following the electromagnetic excitation by Al, Cu, Sn and Pb targets was investigated. The search was made triggering on neutron-rich ions (6He, 8He, 8Li, 9Li, 10Be, 11Be and 13B) detected in the BNL-AGS-E814 spectrometer. An upper limit of 54 ub (at the Confidence Level of 95%) for the electromagnetic dissociation cross-section for an individual channel is set, based on a data sample of ~ 3 x 107 beam particles. Inclusive cross section for the nuclear fragmentation production of those isotopes were measured and forward and transverse energy distribuitions were determined. From a comparison of the experimental momentum distributions for 6He and 9Li with the Goldhaber statistical fragmentation model an average value of 229±9 MeV/c for the Fermi momentum of the 28Si projectile was obtained.
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Norman, Paul. "Hyperon production in p-BE interactions at 158 GeV/c per nucleon at the WA97 CERN experiment." Thesis, University of Birmingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.396234.
Повний текст джерела
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Alvarez, Marcos Aurelio Gonzalez. "Um método para determinação experimental da densidade da matéria nuclear." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-19022014-141107/.
Повний текст джерелаАнотація:
Neste trabalho foi proposto um método de deconvolução para extrair experimentalmente a densidade da matéria nuclear no estado fundamental a partir de dados de espalhamento elástico entre íons pesados em energias baixas (abaixo da barreira de fusão) e intermediárias. A consistência dos resultados foi totalmente verificada. O método se mostrou uma poderosa ferramenta para a determinação experimental da densidade da matéria de núcleos no estado fundamental, particularmente em uma região superficial, onde a diferença entre a densidade de núcleos exóticos e núcleos estáveis vizinhos é muito enfatizada. Foram realizadas medidas de seções de choque de espalhamento elástico para os sistemas 16O + 40Ca, 120Sn, com o objetivo de ajudar na construção de uma sistemática experimental para a parte real da interação nuclear, e para obter a densidade experimental da matéria nuclear no estado fundamental para o núcleo 16O. Como complemento, o trabalho apresenta: i-) uma sistemática teórica das densidades nucleares, realizada para toda região de massa da tabela periódica; ii-) o modelo não-local, desenvolvido para descrever a dependência com a energia da parte real da interação nuclear; e iii-) uma nova representação para a absorção de fluxo, devido aos canais de reação. Com isso, foi desenvolvida uma sistematização para o potencial ótico a partir de uma análise consistente de dados de espalhamento elástico de íons pesados em energias baixas e intermediárias. Esta análise resultou em uma previsão extremamente satisfatória para as seções de choque de espalhamento elástico experimentais, para um vasto conjunto de dados, utilizando um modelo bastante fundamental e global para o potencial ótico e, mais importante, sem a utilização de parâmetros livres.An unfolding method is proposed to extract ground-state nuclear matter densities from heavy-ion elastic scattering data analyses at low (sub-barrier) and intermediate energies. The consistency of the results was fully checked. The method is a powerful tool to obtain ground-state nuclear matter densities, particularly at the surface region where the difference between densities of exotic and stable neighbor nuclei is very emphasized. Precise elastic scattering cross sections were measured for the systems 16O + 40Ca, 120Sn, with the aim of helping the construction of an experimental systematics for the real part of the nuclear interaction, and to obtain the experimental ground-state nuclear matter density for the 16O nucleus. As a complement, this work presents: i-) A theoretical systematics for nuclear densities which was performed for the whole mass region throughout the periodic table, ii-) the non-local model, developed to describe the energy dependence of the real part of the nuclear interaction; iii-) a new representation for the absorption of flux due to the reaction channels. This framework has allowed us to obtain a systematization of the optical potential from a consistent heavy-ion elastic scattering data analysis at low and intermediate energies. This analysis resulted a remarkable prediction for a very large elastic scattering cross section data set using a global and fundamental parameter-free model for the optical potential.
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Turemen, L. M. "Investigation of the adsorption of reactive dyes and heavy metal ions from synthetic textile effluent by eggshell membrane." Thesis, Queen's University Belfast, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368526.
Повний текст джерела
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Mira, Joele Paulus. "The role played by quasi-elastic and inelastic break-up of the 12C and 16O projectiles in the production of intermediate mass fragments at 14-35 MeV/u." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/85756.
Повний текст джерела
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Moura, Marcia Maria de. "Determinação de Escalas Temporais para Reações entre Íons-pesados Leves através de Medidas de Correlações a Momentos Relativos Pequenos." Universidade de São Paulo, 1999. http://www.teses.usp.br/teses/disponiveis/43/43131/tde-31082012-152500/.
Повний текст джерелаАнотація:
Neste trabalho foram realizadas, no Laboratório Pelletron do Instituto de Física da Universidade de São Paulo, medidas de coincidência entre partículas com momentos relativos pequenos para os sistemas 160+10B e 160+ 12C nas energias de 62,5 e 64,0 MeV, respectivamente. Para isso, foi utilizado um hodoscópio composto de 14 telescópios do tipo E-E, capazes de medir a energia tanto de partículas pesadas (Z>2) como leves (Z2). A partir dessas medidas foram obtidos espectros de diferença dos módulos das velocidades (vdif) e funções correlação em momento relativo (prel) para vários pa res de partículas. A análise do espectro de vdif permite determinar a proporção relativa entre as duas seqüências de emissão possíveis para um dado par de partículas. A região da anticorrelação na função correlação permite obter informações sobre a escala temporal referente ao intervalo de tempo entre a emissão da primeira e da segunda partícula. Para o ajuste tanto do espectro de vdif como da função correlação foi utilizado um programa que simula a emissão sequencial de duas partículas a partir de um núcleo composto, no qual a fração das sequências de emissão e a escala temporal são parâmetros ajustáveis. Correlações envolvendo somente partículas leves forneceram resultados para as escalas temporais da ordem de 10-20 s a 10-19 s, compatíveis com evaporação sequencial de um núcleo composto. Correlações envolvendo partículas leves e pesadas forneceram escalas temporais da ordem de 10-20s compatíveis com a fissão de núcleos residuais após a emissão de uma partícula leve.Particle-particle correlation measurements at small relative momenta for the 160+10B and 160+ 12C systems at Elab = 62.5 and 64 MeV, respectively, were performed at the University of São Paulo - Pelletron Laboratory. The experimental setup consisted of a hodoscope composed by fourteen triple telescopes which provide the energy for both light (Z 2 ) and heavy (Z>2) particles. Velocity difference (vdifl) spectra a nd correlation functions at small relative momenta were obtained for many particle pairs. The velocity difference spectrum provides information about the emission order for the particles. The anticorrelation region in the correlation function provides information about the time between the first and second emission. A simulation code that calculates sequencial emission from a compound nucleus and for which the emission order and time scale are parameters was used to fit both the vdiff spectrum and the correlation function. The time scales obtained for light particle correlations are between 10-20 and 10-19 s and they are in agreement with predictions for the evaporation of compound nuclei. Correlations between light and heavy particles give time scales of about 10 -20 which are compatible with fission of the residual nuclei after a light particle emission.
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Trinh, Ngoc Duy. "Emission de neutrons par les réactions d'ions lourds (4,6-95 MeV/nucléon)." Thesis, Normandie, 2018. http://www.theses.fr/2018NORMC234/document.
Повний текст джерелаАнотація:
Les accélérateurs d’ions lourds sont un outil incontournable pour la recherche en physique nucléaire. Ils sont également utilisés pour diverses applications. Il est nécessaire de caractériser la production des neutrons secondaires dans les accélérateurs afin de garantir un fonctionnement sûr en toutes circonstances. Cependant, les données expérimentales sont très rares voire inexistantes. Pour certaines données, on note des divergences entre différentes publications. Des désaccords sont aussi observés entre les mesures et les calculs. Toutes ces raisons justifient le programme Thick Target Neutron Yields (TTNY) dont l’objectif est de mesurer des spectres doublement différentiels (énergie, angle) des neutrons générés par l’interaction des ions lourds (12≤Afaisceau≤208 et 4,6 MeV/nucléon≤Efaisceau≤95 MeV/nucléon) sur cibles épaisses (natC, natCu et natNb). Deux techniques de mesure ont été utilisées : Activation et Temps de vol. Cela permet d’avoir une meilleure confiance dans les mesures, d’étudier les limites expérimentales et de consolider les conclusions que l’on peut en tirer. Les mesures sont comparées à des simulations effectuées dans ce travail avec les codes Monte-Carlo les plus utilisés en calcul nucléaires : PHITS (japonais), FLUKA (européen (CERN/INFN)) et MCNP (américain). Ces comparaisons ont permis d’évaluer la qualité des codes dans les énergies étudiées et pour les masses des noyaux explorées. Elles ont permis aussi de conclure sur les incertitudes systématiques et les éventuelles évolutions à apporter aux modèles physiques de ces codesHeavy-ion accelerators are an essential tool for nuclear physics research. They are also adopted in several applications. It is necessary to characterize the secondary neutrons production in order to guarantee a safe operation in every circumstance in accelerators. However, experimental data are very rare or even non-existent. For some data, we notice disagreements between different publications. Disagreements are also observed between measurements data and simulations. For all these reasons, we established the program Thick Target Neutron Yields (TTNY). This program aims to measure the double differential neutron spectra (energy, angle) generated by the interactions of heavy-ions (12≤Abeam≤208 and 4.6 MeV/nucleon≤Ebeam≤95 MeV/nucleon) on thick targets (natC, natCu and natNb). Two measurements methods were adopted: Activation and Time of Flight. This choice allows having a better confidence on the measurements, studying experimental limits and consolidating the conclusions that could be drawn from the experimental results. The measurements are compared to the simulations performed with some Monte-Carlo widely used in nuclear simulation: PHITS (Japanese), FLUKA (European (CERN/INFN)) and MCNP (American). These comparisons allowed evaluating the modeling quality of heavy-ion reactions for the energies and masses explored in this work. We also conclude on the systematic uncertainties and on the potential improvements to be introduced to physics models of these codes
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Yilmaz, Bulent. "Stochastic Approach To Fusion Dynamics." Phd thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608517/index.pdf.
Повний текст джерелаАнотація:
This doctoral study consists of two parts. In the first part, the quantum statistical effects on the formation process of the heavy ion fusion reactions have been investigated by using the c-number quantum Langevin equation approach. It has been shown that the quantum effects enhance the over-passing probability at low temperatures. In the second part, we have developed a simulation technique for the quantum noises which can be approximated by two-term exponential colored noise.
38
Elhage, Hicham. "Réaction 40Ca+natCu à 35 MeV/nucléon mesurée avec le multidétecteur AMPHORA : étude de l'énergie d'excitation et du moment angulaire du quasi-projectile reconstitué." Grenoble 1, 1992. http://www.theses.fr/1992GRE10145.
Повний текст джерелаАнотація:
Dans ce travail, nous avons etudie les mecanismes d'interaction entre les ions calcium a 35 mev/nucleon et une cible de cuivre. Les mesures ont ete faites avec le multidetecteur amphora. Nous avons montre la necessite de simuler la fonction de reponse d'amphora. Afin d'interpreter les resultats experimentaux, trois modeles traitant differemment la dynamique de l'interaction ont ete utilises. Lors de l'analyse des donnees, nous n'avons retenu que les evenements de nature binaire dans la phase initiale. Des criteres de selection cinematiques bases sur des considerations de vitesse relative ont ete utilises, afin d'isoler les particules et residus issus de la desexcitation du quasi-projectile. La reconstitution de ce noyau nous a permis de definir un plan de reaction et de calculer un bilan en energie evenement par evenement. Nous avons propose une methode de determination du moment angulaire basee sur l'asymetrie d'emission de particules legeres par rapport a la normale au plan de reaction. Les moments angulaires estimes sont en bon accord avec les previsions des modeles. La temperature du quasi-projectile a ete estimee a partir des spectres en energie cinetique des particules legeres. L'independance de mesure des trois caracteristiques energie d'excitation, temperature et moment angulaire nous a permis de determiner le parametre de densite de niveaux. Ce dernier n'evolue pas en fonction de l'energie d'excitation et vaut a/8. En ce qui concerne la caracterisation des modes de desexcitation du quasi-projectile, nous pensons que le mode predominant est l'evaporation
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Burgugi, Rogerio Gregorio. "Fragmentação nuclear em colisões de íons pesados a energias relativísticas." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-23102009-093957/.
Повний текст джерелаАнотація:
Foi investigada a correlação entre a energia transversa (ET) produzida e a energia de partículas neutras (En) emitidas em colisões de íons de 28Si (plab=14.6 GeV/c por nucleon) com alvos de Al, Cu e Pb, estudadas pelo Experimento 814 no acelerador AGS do Laboratório Nacional de Brookhaven. A correlação entre a energia transversa e a energia dianteira produzida em colisões com emissão dos fragmentos 2H, 3H, 3He, 4He, 6He, 5Li e 6Li também foi investigada. Foi observado que a energia En dianteira produzida pelas partículas neutras tem uma forte dependência com a energia transversa ET produzida na colisão. Uma parametrização eficiente dos dados é obtida utilizando um modelo estatístico que relaciona o numero de espectadores da colisão com o numero de nêutrons detectados na região dianteira. As distribuições de momento desses fragmentos foram investigadas através do modelo de Goldhaber e os seus respectivos parâmetros 0 foram calculados para os eventos referentes as colisões de 28Si com alvos de Al, Cu e Pb.We carried out a study of the forward neutral energy (En) and its correlation with the produced transverse energy (ET ) in collisions of 28Si ions (plab=14.6 GeV/c per nucleon) with Al, Cu, and Pb targets, investigated by Experiment 814 at the Brookhaven AGS. The correlation of the produced transverse energy with forward neutral energy from fragments 2H, 3H, 3He, 4He, 6He, 5Li and 6Li was also investigated. We find that the forward neutral energy En has a strong dependence on transverse energy ET produced in the collision. An efficient parametrization of this data set is accomplished through the use of a statistical model which relates the number of spectators in the collision to the number of neutrons detected in the forward direction. Momentum distributions of the fragments were investigated through the use of the Goldhaber model and the 0 parameter was calculated to each of the fragments in reactions of 28Si with Al, Cu and Pb targets.
40
Andgren, Karin. "Studies of collective phenomena in neutron deficient nuclei : by means of lifetime measurements, angular correlation measurements and the recoil decay tagging technique /." Doctoral thesis, KTH, Fysik, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4693.
Повний текст джерела
41
Seddiki, Sélim. "Contribution au développement du détecteur de Vertex de l'expérience CBM et étude de faisabilité des mesures du flot elliptique des particules à charme ouvert." Phd thesis, Université de Strasbourg, 2012. http://tel.archives-ouvertes.fr/tel-00862654.
Повний текст джерелаАнотація:
CBM, une des expériences majeures du nouvel accélérateur FAIR en cours de construction au GSI (Darmstadt), a pour objectif d'explorer le diagramme des phases de la matière nucléaire dans la région des hautes densités baryoniques nettes. Un de ses principaux thèmes de physique est l'étude de la production des particules à charme ouvert dans les collisions d'ions lourds. La mesure directe de ces particules nécessite l'utilisation d'un détecteur de vertex très précis. La présente thèse est une contribution à la conception et au développement de ce détecteur, appelé MVD. Une première partie de la thèse concerne l'évaluation, à l'aide de simulations réalistes, des flots de données à transmettre par les capteurs qui équiperont la première génération du MVD. Les résultats obtenus montrent que les performances attendues des capteurs permettront de mener à bien le programme de physique de CBM. Une deuxième partie porte sur les performances attendues pour la reconstruction des particules à charme ouvert, à travers leur désintégration hadronique, dans les collisions Au+Au. Des simulations détaillées ont permis de démontrer que la reconstruction du méson D+ → π+ π+ K-, par exemple, est faisable avec une efficacité de reconstruction de 2% et un rapport signal/bruit de 1.5. La statistique attendue en deux mois de prises de données a été évaluée à environ 6.9 x 104 mésons D. Dans la dernière partie, il a été montré que cette statistique permettrait d'effectuer des études détaillées du flot elliptique intégré des mésons D. La mesure du flot elliptique différentiel de ces particules requerrait, cependant, des statistiques plus élevées, et donc l'utilisation de capteurs plus performants.
42
Lamotte, Maxime. "Etude du signal optique des chambres à fission et évaluation de son exploitation pour un système de mesure neutronique d'un réacteur de génération IV Development and first use of an experimental device for fission-induced spectrometry applied to neutron flux monitoring SCENA: A simulation tool for radiation-induced gas scintillation Simulation of heavy-ion slowing-down tracks with the SCENA code Design and irradiation test of an innovative optical ionization chamber technology Pulse-reactor core monitoring with an innovative optical neutron detector." Thesis, Université Grenoble Alpes, 2021. http://www.theses.fr/2021GRALI023.
Повний текст джерелаАнотація:
Cette thèse de doctorat expose l'étude la luminescence induite dans des capteurs à gaz de type chambre à fission, afin d'évaluer son utilisation pour le suivi de puissance des réacteurs nucléaires de quatrième génération comme ASTRID.Le dépôt d'énergie dans un gaz par des ions lourds produits lors de fissions nucléaires dans une chambre à fission est d'ordinaire exploité pour sa capacité à produire des charges libres, qui peuvent être détectées avec des électrodes. Cette méthode, utilisée depuis le début de l'ère atomique, n'est pas sans inconvénients, et des axes d'amélioration ont été clairement identifiés.En estimant la production d'états excités du gaz d'une chambre à fission classique, on déduit que de la lumière peut être émise en son sein, et être détectée par un photo-détecteur. L'utilisation du signal optique plutôt qu'électrique apporte une robustesse accrue aux systèmes de mesures neutroniques, insensibles au bruit électromagnétique.L'étude spectroscopique d'un plasma d'origine nucléaire dans un dispositif analytique dimensionné et conçu par nos soins permet d'enregistrer des spectres de raies d'émission caractéristiques de la scintillation du gaz. L'analyse de ses raies permet d'affirmer la supériorité de la détection optique de neutrons, car la pression et la composition du gaz de remplissage peuvent alors être estimées en ligne.Parallèlement à nos activités expérimentales, un code de simulation de la dynamique de peuplement des niveaux des plasmas froids excités par ions-lourds est développé afin d'optimiser de futurs détecteurs basés sur ce principe. Les temps caractéristiques nécessaires à la génération d'états radiatifs et la position des excitations autour d'une trace d'ionisation ont été estimés.Plusieurs prototype de capteurs de neutrons fonctionnant uniquement sur un principe optique sont exploités dans des faisceaux de neutrons froids du réacteur Orphée afin de vérifier la preuve de concept d'un tel système de mesure neutronique. Des essais dans le réacteur Cabri permettent quant à eux de quantifier la limite de détection, la linéarité et la dynamique du système.Les très bons résultats apportés par ces trois volets valident la preuve de concept de la détection passive et en ligne de neutrons, capable d'auto-diagnostic, pour des applications exigeantes en milieu difficileThis PhD thesis details the study of luminescence produced in gaseous detectors as fission chambers, to evaluate its use in 4th generation nuclear reactor power monitoring, as ASTRID.Energy deposition in the gas, from heavy-ions produced during nuclear fission in a fission chamber is usually used for its charge generation ability, that can be detected with electrodes. Such method has been used since the beginning of atomic era present disadvantages, and necessary improvements have been assessed.By estimating fission chamber gas excited states production, one can deduce intrinsic light emission, and its detection by appropriate photo-detectors. Use of an optical signal against an electric one improves dependability of a neutron flux monitoring system, immune to electromagnetic noise.Spectroscopic studies of a nuclear plasma in a self-designed analytical device allows observation of typical gas scintillation emission lines. Analysis of emission lines reinforce optical detection attraction, as pressure and gas composition can be monitored online.Alongside our experiments, a simulation code dedicated to heavy-ions induced cold-plasma excited levels population has been produced to optimise future detectors relying on optical emission. Typical times encountered for excited states generation and their position around an ionization track have been estimated.Several neutron detector prototypes based on the sole gas scintillation principle have been assessed in cold neutron beam lines of the Orphée reactor, to validate a proof of concept for neutron monitoring. Experiments on the Cabri reactor allowed quantification of detection limit, linearity and dynamic range of our system.The positive outcomes provided by these 3 lines of work validate the proof of concept of passive, on-line, and self-diagnosed neutron detection with high dependability in harsh environments
43
Orr, Nigel Andrew. "Heavy-ion reaction studies of nuclei far from stability." Phd thesis, 1989. http://hdl.handle.net/1885/12477.
Повний текст джерелаАнотація:
Heavy-ion multi-nucleon transfer reactions have been used to investigate a number of nuclei far from stability in the mass range A= 20 to 39. Measurements of the masses and excited states have been made for the nuclei 20N, 22.23F, 35,36,37P and 39Sc. The 39Sc mass determination is the first reported measurement and indicates that the nucleus is unbound to ground state proton emission by 580±30 keV. The first information on the level schemes of 23F, 37P and 39Sc has also been forthcoming, whiie a substantial amount of new data has been obtained for the other nuclei investigated. The probable structure of many of the new and previously reported levels observed in the present work are. deduced through comparison with shell model and DWBA calculations and by analogy with similar reactions. Where comparison is possible, the results presented here are in general in good agreement with those obtained by earlier studies. The mass evaluations for 20N and 37P are, however, notable exceptions. There is evidence that 37p may be ~0.7 MeV more bound than previously accepted, although further work will be required to confirm this. In contrast, 20N appears to be ~1 MeV less bound than previous determinations suggest. A possible explanation for this discrepancy is advanced. A number of techniques have been developed in the course of the work described here to aid in the detection of very low yield reaction products. These comprise a system to measure the time-of-flight of ions around a magnetic spectrograph, a normal incidence focal plane detector and a system for the production of very pure isotopic targets via ion implantation. Descriptions of these systems and associated techniques are presented.
44
Saloner, David Athol. "A semi-microscopic calculation of the potential in heavy ion collisions." Thesis, 2015. http://hdl.handle.net/10539/18602.
Повний текст джерела
45
Vo-Phuoc, Kirsten. "Microscopic approach to heavy-ion reactions." Phd thesis, 2018. http://hdl.handle.net/1885/147216.
Повний текст джерелаАнотація:
Heavy-ion reactions are affected by the nuclear structure of the
reactants and other dynamical processes during the collision.
Theoretical studies of such reactions lead to a clearer
understanding of prohibitive mechanisms to heavy-ion fusion. One
application of this is superheavy element formation, where
quasifission is the major competing process to the formation of a
compound nucleus in this region of the nuclear chart.
Microscopic approaches that use mean field approximations, such
as the time-dependent Hartree-Fock (TDHF) theory, have been
increasingly used to study low energy heavy-ion reactions. In
addition to reactions, nuclear structure properties can also be
studied with microscopic theory. Such approaches do not require
empirical knowledge of the nucleus and
can be used as a predictive tool for studying structure or
reactions involving exotic nuclei. In this thesis, TDHF is used
to study nuclear vibrations and heavy-ion reactions at near
barrier energies.
The TDHF approach is applied first to a systematic study of
low-lying octupole and quadrupole vibrational modes of {40-54}Ca
isotopes. Then, fusion reactions are calcuated for Ca+Sn systems,
using the barrier energy as the main observable. Fusion reactions
are first calculated with no couplings (static HF calculations)
before including all dynamics that the mean field approximation
offers (TDHF calculations). The addition of dynamics often
results in a lower
fusion barrier compared to the static barrier, with the exception
of systems involving the neutron rich {52,54}Ca projectiles. The
difference in fusion barriers between the two sets of
calculations are explored by considering couplings to vibrational
states and transfer channels. To separate the effects of
individual couplings, the coupled-channels approach is used with
the HF calculations of the vibrational states as inputs. Such
couplings account for most of the lowering of the static barrier.
For the most neutron rich systems, coupling to vibrational states
does not account for the dynamical barrier increase. Transfer
channels, in particular proton pickup, are explored within TDHF
and
may play a role in this increased barrier energy.
Following from fusion reactions, the factors and dynamics that
may hinder fusion in heavier systems are studied in the reactions
48Ca, 50Ti, 52Cr, 54Fe, 56,64Ni, 58Zn+208Pb at energies ranging
from 0% to 30% above the static HF barrier.
Although most of these systems fuse at energies within this
range, some systems reseparate for which emission of nucleons was
apparent at scission point. The contact times were in most cases
less than 10 zs and the attempt at $N/Z$ equilibration of these
systems happen on fast time scales (1-2 zs). Larger amounts of
mass transfer occur in systems with longer neck times and fewer
magic numbers such as 34S+232Th and Cr+Pt systems that were also
calculated for comparison. Further studies are required to better
understand the role of shell effects as well as nucleon
emission
in quasifission reactions, and subsequently reactions leading to
superheavy element formation.
46
Wei, Jian Xin. "Barrier distributions in heavy ion induced fusion reactions." Phd thesis, 1993. http://hdl.handle.net/1885/138677.
Повний текст джерела
47
"Reduction of longitudinal emittance of ion beams caused by the variation in acceleration gap voltages." 2012. http://library.cuhk.edu.hk/record=b5549179.
Повний текст джерелаАнотація:
重離子核聚變是一種能源技術，它有可能為人類未來提供無限的潔淨能源。通過高能粒子撞擊含高濃度氘和氚的目標，從而產生強大的壓縮衝擊波，最終引發氘和氚核子聚變並釋放出巨大核能。在過去的幾十年裡，從離子注入到核反應控制技術，以至於整個重離子核聚變的基本概念都得到迅速的發展。其中一個重要的核聚變條件就是要求非常低的離子束的縱向發射度。在論文的第一部分，我們研發了一種TSC 技術，它可以減少因粒子加速器的電壓變化而引起的縱向發射度增長。通過數值模擬，結果表明離子束的縱向發射度得到了約89% 的降低。如果把TSC 技術應用於重離子核聚變，離子束的縱向發射度就可以有效地被降低，從而促進更高效的核聚變反應。在論文的第二部分，我們以離子束的電流信號分析為基礎，研發了一種非干擾性的離子束能量測量方法。對於傳統干擾性的離子束能量測量，這種強調非干擾性的測量方法對未來重離子核聚變實驗以及高能粒子加速器研發都有實質的應用價值。在論文的第三部分，我們從NDCX 實驗數據分析中，證實離子束的電流信號能夠有效地揭示離子束微弱的能量變化。這個實驗結果相應肯定了論文第二部分的電流信號分析處理方法。在論文的第四部分，我們模擬在真實的NDCX 環境下測試TSC 技術。模擬結果表明TSC 技術可有效地把離子束的縱向發射度減少近89% ，從而證明了TSC 技術在實際應用中的能力。在論文的最後部分，我們在強電流離子束的一維波動行為中引入橫縱向稱合分析，解釋了一維波動行為與數值模擬結果之間的細小偏差。
Heavy Ion Fusion (HIF) is a technology that has the potential to provide an unlimited source of clean energy for human future. HIF works by shooting at a capsule containing Deuterium and Tritium with energetic heavy ion beams such that the huge amount of kinetic energy carried by the ions is converted into strong compression shock waves. DT fuel is then compressed to form a high temperature and high density hotspot at the center of the capsule, thus igniting nuclear fusion between Deuterium and Tritium. Over the past few decades, the fundamental concepts of HIF had been tested in scaled ex¬periments from the source injection to the reaction chamber. To achieve the highest performance of ignition, ion beams with low longitudinal emittance is demanded.
In the first part of the thesis, we developed a novel Two-Step Correction (TSC) technique to reduce the growth of longitudinal emittance in an induc¬tion linac driver caused by variations in acceleration gap voltages. Through numerical studies, we achieved a reduction of longitudinal emittance by about 89% for high perveance ion beams. As a spinoff from the formalism developed in this study, we developed in the second part of the thesis a new non-invasive approach for the measurement of ion beam energy. The proposed diagnostics may have practical utility for future HIF experiments, particularly as higher energy accelerators are developed. It works by a generalized time-of-flight method, using two adjacent beam current signals to reconstruct the beam velocity profile. In the third part of the thesis, we verified that beam current signals are capable to reveal small beam energy variations by an NDCX-I experiment performed at Lawrence Berkeley National Laboratory. The result of this experiment confirms the formalism of the new non-invasive approach for the ion beam energy determination based on beam current signal analysis. In order to verify the effectiveness of TSC in real drivers, we proposed a new NDCX-I experiment in the fourth part of the thesis to test the limitations and performance of the correction technique in real environment. Through simulations with real driver features considered, a reduction of 89% of longitudinal emittance was observed, which confirms the ability of TSC in real applications. In the last part of the thesis, we revealed the limitation of the 1-D cold fluid model deployed in our analysis of space-charge waves for high perveance ion beams. We showed that inaccuracies are caused by transverse-longitudinal coupling which could be included in the wave equation for space-charge dominated beams.
Detailed summary in vernacular field only.
Detailed summary in vernacular field only.
Woo, Ka Ming = 抑制由粒子加速器的電壓變化所引起的縱向發射度 / 胡家明.
Thesis (M.Phil.)--Chinese University of Hong Kong, 2012.
Includes bibliographical references (leaves 153-156).
Abstracts also in Chinese.
Woo, Ka Ming = Yi zhi you li zi jia su qi de dian ya bian hua suo yin qi de zong xiang fa she du / Hu Jiaming.
Abstract --- p.ii
概論 --- p.iv
Acknowledgement --- p.v
Chapter 1 --- Introduction --- p.1
Chapter 2 --- Background --- p.4
Chapter 2.1 --- Highlight --- p.4
Chapter 2.2 --- Introduction to fusion energy --- p.4
Chapter 2.3 --- Fusion technology --- p.5
Chapter 2.3.1 --- Magnetic confinement fusions --- p.5
Chapter 2.3.2 --- Inertial confinement fusions --- p.7
Chapter 2.4 --- Inertia confinement fusion --- p.9
Chapter 2.4.1 --- Principle of ICF --- p.9
Chapter 2.4.2 --- Implosion dynamics --- p.11
Chapter 2.4.3 --- Rayleigh-Taylor instability --- p.13
Chapter 2.4.4 --- Fast ignition --- p.14
Chapter 2.5 --- Heavy Ion Fusion --- p.16
Chapter 2.5.1 --- Comparison between laser and heavy ion driven fusions --- p.16
Chapter 2.5.2 --- Linear Induction Accelerator --- p.18
Chapter 2.6 --- Operation of a HIF driver --- p.20
Chapter 2.6.1 --- Source injection --- p.20
Chapter 2.6.2 --- Transport of ion beams --- p.21
Chapter 2.6.3 --- Acceleration of ion beams --- p.22
Chapter 2.6.4 --- Neutralized drift longitudinal compression --- p.24
Chapter 2.6.5 --- Target chamber --- p.25
Chapter 2.7 --- Transverse beam dynamics --- p.26
Chapter 2.7.1 --- Beam envelope equation --- p.26
Chapter 2.7.2 --- Matched beams solutions --- p.29
Chapter 2.8 --- Longitudinal beam dynamics --- p.30
Chapter 2.8.1 --- Cold plasma model --- p.30
Chapter 2.8.2 --- Self longitudinal electric field --- p.32
Chapter 2.8.3 --- Longitudinal emittance --- p.34
Chapter 2.9 --- Intense ion beam simulation --- p.35
Chapter 2.9.1 --- Particle-In-Cell method --- p.35
Chapter 2.9.2 --- WARP code --- p.36
Chapter 2.10 --- Conclusion --- p.37
Chapter 3 --- Techniques for correcting velocity and density fluctuations of ion beams --- p.39
Chapter 3.1 --- Highlight --- p.39
Chapter 3.2 --- The quest for short-pulse length ion beams --- p.40
Chapter 3.2.1 --- Applications of short-pulse ion beams --- p.40
Chapter 3.2.2 --- Consequence of the growth of longitudinal emittance --- p.41
Chapter 3.3 --- Effect of gap voltage variation on εzn --- p.42
Chapter 3.3.1 --- Description of simulation scenario --- p.42
Chapter 3.3.2 --- The coasting of an unperturbed ion beam and a velocitytilt beam --- p.43
Chapter 3.3.3 --- Effect of many constant voltage gaps --- p.44
Chapter 3.3.4 --- Effect of non-uniform voltage gap --- p.46
Chapter 3.4 --- One-step correction --- p.48
Chapter 3.4.1 --- Criteria for the one-step correction --- p.52
Chapter 3.4.2 --- Space-charge dominated beams --- p.55
Chapter 3.5 --- Two-step correction --- p.56
Chapter 3.5.1 --- Principle of two-step correction --- p.56
Chapter 3.5.2 --- Result of two-step correction --- p.59
Chapter 3.6 --- Conclusion --- p.62
Chapter 4 --- A new non-invasive approach for the measurement of ion beam energy --- p.63
Chapter 4.1 --- Highlight --- p.63
Chapter 4.2 --- Introduction --- p.64
Chapter 4.3 --- Derivation of the ion beam energy based on two current signals --- p.65
Chapter 4.3.1 --- Obtaining the time evolution of the beam current --- p.65
Chapter 4.3.2 --- Deriving the beam energy profile --- p.67
Chapter 4.3.3 --- Obtaining the average velocity --- p.70
Chapter 4.4 --- Checking the beam energy profile with 3-D PIC simulations --- p.72
Chapter 4.4.1 --- Determination of the average velocity --- p.73
Chapter 4.4.2 --- Computation of the beam energy profile --- p.74
Chapter 4.5 --- Signal magnification --- p.74
Chapter 4.6 --- Error propagations --- p.77
Chapter 4.7 --- Conclusion --- p.81
Chapter 5 --- Experimental verification of the beam current signal amplification --- p.83
Chapter 5.1 --- Highlight --- p.83
Chapter 5.2 --- Introduction to NDCX-I --- p.84
Chapter 5.3 --- Design of the NDCX-I experiment --- p.88
Chapter 5.4 --- Voltage profiles applied at the source plate --- p.90
Chapter 5.4.1 --- Marx voltage profile --- p.90
Chapter 5.4.2 --- Voltage modulation --- p.91
Chapter 5.5 --- Signal amplification of beam currents measured at the Faraday cup --- p.92
Chapter 5.6 --- Modeling of the space-charge wave propagation --- p.94
Chapter 5.6.1 --- Solving for the line-charge density profile at the source plate --- p.94
Chapter 5.6.2 --- Procedure of space-charge wave modeling --- p.99
Chapter 5.7 --- Conclusion --- p.101
Chapter 6 --- Implementation of Two-Step Correction in NDCX-I --- p.103
Chapter 6.1 --- Highlight --- p.103
Chapter 6.2 --- Application of the current signal analysis to the Two-Step Correction --- p.104
Chapter 6.3 --- Proposal of the new NDCX-I experiment --- p.107
Chapter 6.3.1 --- Design of the beamline --- p.107
Chapter 6.3.2 --- Description of the simulation scenario --- p.110
Chapter 6.3.3 --- Result of the Two-Step Correction simulation --- p.114
Chapter 6.4 --- Conclusion --- p.126
Chapter 7 --- Transverse-Longitudinal coupling in the wave equation --- p.128
Chapter 7.1 --- Highlight --- p.128
Chapter 7.2 --- Phenomenological study of residue --- p.129
Chapter 7.2.1 --- Description of the simulation scenario --- p.129
Chapter 7.2.2 --- Modeling of the velocity wave --- p.131
Chapter 7.2.3 --- Phenomenon of residue --- p.133
Chapter 7.3 --- Review of the space-charge wave equation --- p.141
Chapter 7.3.1 --- Fluid description of ion beams --- p.141
Chapter 7.3.2 --- Beam envelope perturbation --- p.145
Chapter 7.4 --- Conclusion --- p.149
Chapter 8 --- Conclusion --- p.150
Bibliography --- p.153
48
Chen, Chun-Hsing, and 陳俊興. "EFFECTS OF COMPLEXATION REACTIONS ON HEAVY METAL ION EXCHANGE PROCESSES." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/13029823721451937861.
Повний текст джерела
49
Bokhorst, J. J. M. "Angular momentum distributions of fusion deduced from heavy-ion reactions." Phd thesis, 1986. http://hdl.handle.net/1885/138674.
Повний текст джерела
50
Soisson, Sarah Nicole. "Isospin Dependence of Fragmentation." Thesis, 2010. http://hdl.handle.net/1969.1/ETD-TAMU-2010-12-8946.
Повний текст джерелаАнотація:
Multifragmentation reactions have been used to study many of the complexities of the nucleus. Recently, work has been done to tie observables from multifragmentation reactions to astrophysical observables used in supernova explosions. To make this connection, it is necessary to have a highly excited, equilibrated system. The creation of a highly excited system is done for this dissertation by the reaction of one projectile, ³²S, on three targets, ¹¹²⁾¹²⁴Sn and ^natAu at 45 MeV/nucleon. The forward array using silicon technology, FAUST, was used to collect the fragments produced from the excited projectiles. The motivation for this study was to isotopically identify the fragmenting source and to understand the relationship between its N/Z and the resulting fragmentation. This can then be used to constrain theoretical models which predict the evolution of supernova explosions. Using an isotropically identified source, the resulting fragmentation of the projectile has been studied. It is shown that there are dependencies on the fragment mass distribution, fragment charge distribution and source excitation energy from the source N/Z. Looking more specifically at the fragments produced, it was found that there is a parallel velocity anisotropy in the particle emission. This anisotropy is found to be a direct result of the presence of an external Coulomb field. Using DIT+SMM theoretical calculations, the anisotropy has been found to be dependent on the distance at which the projectile breaks up from the target (external Coulomb field). As the parallel velocity is related to the angle of emission, it is of interest to extract out the average kinetic energy of each isotope to determine if there are differences in the average kinetic energy by the angle of emission. It is found that the average kinetic energy is dependent on the emission angle in the quasi-projectile frame. Because of this, care should be taken when comparing between systems to ensure similar regions are being compared. However, the observation that the average kinetic energy changes as a function of the emission angle is not dependent on the presence of an external Coulomb field. Using DIT+SMM calculations, the differences between the average kinetic energy from different angles of emission are seen even when no external Coulomb field is present. These changes are attributed to the angular momentum. In all cases, a statistical framework, supplied by DIT+SMM calculations, can explain many phenomena seen from a fragmenting nucleus. However, the accuracy of the model varies when moving from a neutron-poor to a neutron-rich source.