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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

The effect of the ileal brake on the behaviour of oral dosage forms within the small intestine

Dobson, Clair Louise January 1999 (has links)
No description available.
192

The theory of pre-equilibrium processes in nuclear reactions

Chadwick, Mark Benjamin January 1989 (has links)
No description available.
193

The construction and analysis of a whole-sky map using underground muons

Giller, Graham L. January 1994 (has links)
No description available.
194

Sistemas de Absorción en Espectros Ópticos de Estallidos de Rayos Gamma

Tejos Salgado, Nicolás Andrés January 2009 (has links)
No description available.
195

Gamma Ray Distribution from Neutron Excitation in Cesium

Bowers, Richard Morgan 01 1900 (has links)
The purpose of this investigation was to analyze the gamma rays resulting from excitation of Cs133 by the inelastic scattering of 14 MeV neutrons and to determine the relative intensity of each gamma ray.
196

THE AFTERGLOW AND EARLY-TYPE HOST GALAXY OF THE SHORT GRB 150101B AT z = 0.1343

Fong, W., Margutti, R., Chornock, R., Berger, E., Shappee, B. J., Levan, A. J., Tanvir, N. R., Smith, N., Milne, P. A., Laskar, T., Fox, D. B., Lunnan, R., Blanchard, P. K., Hjorth, J., Wiersema, K., van der Horst, A. J., Zaritsky, D. 14 December 2016 (has links)
We present the discovery of the X-ray and optical afterglows of the short-duration GRB 150101B, pinpointing the event to an early-type host galaxy at z = 0.1343 +/- 0.0030. This makes GRB 150101B the most nearby short gamma-ray burst (GRB) with an early-type host galaxy discovered to date. Fitting the spectral energy distribution of the host galaxy results in an inferred stellar mass of approximate to 7 x 10(10) M-circle dot, stellar population age of approximate to 2-2.5 Gyr, and star formation rate of less than or similar to 0.4M(circle dot) yr(-1). The host of GRB 150101B is one of the largest and most luminous short GRB host galaxies, with a B-band luminosity of approximate to 4.3L(*) and half-light radius of approximate to 8 kpc. GRB 150101B is located at a projected distance of 7.35 +/- 0.07. kpc from its host center and lies on a faint region of its host rest-frame optical light. Its location, combined with the lack of associated supernova, is consistent with an NS-NS/NS-BH merger progenitor. From modeling the evolution of the broadband afterglow, we calculate isotropic-equivalent gamma-ray and kinetic energies of approximate to 1.3 x 10(49) erg and approximate to(6-14) x 10(51) erg, respectively, a circumburst density of approximate to(0.8-4) x 10(-5) cm(-3), and a jet opening angle of greater than or similar to 9 degrees. Using observations extending to approximate to 30 days, we place upper limits of less than or similar to(2-4) x 10(41) erg s(-1) on associated kilonova emission. We compare searches following previous short GRBs to existing kilonova models and demonstrate the difficulty of performing effective kilonova searches from cosmological short GRBs using current ground-based facilities. We show that at the Advanced LIGO/VIRGO horizon distance of 200 Mpc, searches reaching depths of approximate to 23-24 AB. mag are necessary to probe a meaningful range of kilonova models.
197

Methods of neutron flux determination by means of organic scintillator in neutron-gamma ray mixed field.

January 1987 (has links)
by Chan Chi-Ming. / Chinese title in romanization: Zai zhong zi-r she xian hun he chang zhong, yong you ji shan yue ti ce liang zhong zi tong liang di fang fa. / Thesis (M.Ph.)--Chinese University of Hong Kong, 1987. / Bibliography: leaves 142-149.
198

Measurements and analysis of gamma-ray streaming through concrete lined ducts

Stucker, David Lee January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
199

Benchmark skyshine exposure rates

Roseberry, Murray Lee January 2011 (has links)
Digitized by Kansas Correctional Industries
200

Ultra-high-energy neutrinos and cosmic rays from gamma-ray bursts: exploring and updating the connection / Ultra-Hochenergie-Neutrinos und die kosmische Strahlung von Gammastrahlenausbrüche: die Erforschung und die Aktualisierung der Verbindung

Bustamante, Mauricio January 2014 (has links) (PDF)
It is natural to consider the possibility that the most energetic particles detected (> 10^18 eV), ultra-high-energy cosmic rays (UHECRs), are originated at the most luminous transient events observed (> 10^52 erg s^-1), gamma-ray bursts (GRBs). As a result of the interaction of highly-accelerated, magnetically-confined protons and ions with the photon field inside the burst, both neutrons and UHE neutrinos are expected to be created: the former escape the source and beta-decay into protons which propagate to Earth, where they are detected as UHECRs, while the latter, if detected, would constitute the smoking gun of hadronic acceleration in the sources. Recently, km-scale neutrino telescopes such as IceCube have finally reached the sensitivities required to probe the neutrino predictions of some of the existing GRB models. On that account, we present here a revised, self-consistent model of joint UHE proton and neutrino production at GRBs that includes a state-of-the-art, improved numerical calculation of the neutrino flux (NeuCosmA); that uses a generalised UHECR emission model where some of the protons in the sources are able to "leak out" of their magnetic confinement before having interacted; and that takes into account the energy losses of the protons during their propagation to Earth. We use our predictions to take a close look at the cosmic ray-neutrino connection and find that the current UHECR observations by giant air shower detectors, together with the upper bounds on the flux of neutrinos from GRBs, are already sufficient to put tension on several possibilities of particle emission and propagation, and to point us towards some requirements that should be fulfilled by GRBs if they are to be the sources of the UHECRs. We further refine our analysis by studying a dynamical burst model, where we find that the different particle species originate at distinct stages of the expanding GRB, each under particular conditions. Finally, we consider a possibility of new physics: the effect of neutrino decay in the flux of UHE neutrinos from GRBs. On the whole, our results demonstrate that self-consistent models of particle production are now integral to the advancement of the field, given that the full picture of the UHE Universe will only emerge as a result of looking at the multi-messenger sky, i.e., at gamma-rays, cosmic rays, and neutrinos simultaneously. / Es ist eine natürliche Annahme, dass die energiereichsten beobachteten Teilchen (> 1018 eV), die ultra-hochenergetische Kosmische Strahlung (UHECRs), möglicherweise in Verbindung mit den leuchtkräftigsten zeitlich beschränkten Ereignissen (> 1052 erg s−1), sogenannten Gammablitzen (GRBs), stehen. Als Folge der Wechselwirkungen zwischen den extrem beschleunigten, in Magnetfeldern gefangenen Protonen und Ionen und den Photonfeldern im Inneren der Gammablitze wer- den sowohl Neutronen als auch UHE Neutrinos erwartet. Erstere köonnen die Quelle verlassen und zerfallen zu Protonen via β-Zerfall, welche zur Erde propagieren und dort als UHECR detektiert werden köonnen, während Letztere, wenn detektiert, den eindeutigen Beweis für die Beschleunigung von Hadronen in besagten Quellen erbringen würden. Vor Kurzem haben km3-große Neutrinoteleskope, wie IceCube, endlich die benötigte Sensitivität erreicht, um die Neutrinovorhersagen für einige existierende GRB-Modelle zu testen. In diesem Zusammenhang präsentieren wir hier ein überarbeitetes, selbstkonsistentes Modell der gemein- samen Produktion von UHE Protonen und Neutrinos in GRBs. Dieses enthält eine hochmoderne, verbesserte numerische Kalkulation des Neutrinoflusses (NeuCosmA), ein verallgemeinertes Emissionsmodell für UHECR, welches darauf beruht, dass einige Protonen direkt aus den Magnetfeldern innerhalb der Quelle entkommen können ohne wechselzuwirken, und bezieht die Energieverluste der Protonen auf ihrem Weg zur Erde mit ein. Wir nutzen unsere Voraussagen, um einen genaueren Blick auf die Verbindung zwischen Kosmischer Strahlung und Neutrinos zu werfen, und stellen fest, dass aktuelle UHECR Beobachtungen mittels gigantischen Luftschauerdetektoren zusammen mit den oberen Schranken auf den Neutrinofluss von GRBs bereits ausreichen, um Widersprüche zu einigen Emissions- und Propagationsmodellen aufzuzeigen, und deuten uns in die Richtung einiger Voraussetzungen, die von GRBs erfüllt sein müssen, sollten diese die Quellen der UHECRs sein. Des Weiteren verfeinern wir unsere Analyse, indem wir ein dynamisches Explosionsmodell studieren, mittels welcher wir herausfinden, dass unterschiedliche Teilchen von bestimmten Phasen des expandieren GRBs stammen, welche durch unterschiedliche Bedingungen charakterisiert sind. Zum Schluss betrachten wir die Möglichkeit von ”neuer Physik”, den Zerfall von UHE Neutrinos im Neutrinofluss von GRBs. Im Großen und Ganzen zeigen unsere Ergebnisse, dass selbstkonsistente Modelle mittlerweile ein integraler Bestandteil für den Fortschritt dieses Feldes geworden sind, wenn man berücksichtigt, dass der Gesamtzusammenhang des UHE Universums erst sichtbar wird, wenn man den Himmel in unterschiedlichen Kanälen betrachtet, genauer gesagt gleichzeitig in Gammastrahlung, in Kosmischer Strahlung und in Neutrinos.

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