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Cosmological constraints with future radio surveysAbdalla, Filipe B. January 2006 (has links)
No description available.
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'They Ain't Afraid of no Ghosts': Dark Tourism at Historic SitesJohnson, Kaci Lynn January 2020 (has links)
Dark tourism, a subsection of heritage tourism, is growing in popularity and center around historic sites and museums. Those sites are put in the position to take advantage of the surging popularity of dark tourism by offering programming that complements it. Ghost tours, paranormal investigations, and haunted houses have all been utilized by museums and historic sites to boost revenue and attendance numbers. The implementation of dark programming raises difficult discussions on the role of museums in society and the ethics of profiting off of ghosts, spirits, and the paranormal. The decision to produce dark programming as a complement to dark tourism is best decided on a case to case basis, as no two museums or historic sites are the same. But every site that is considering dark programming needs to weigh their mission, ethics, their stakeholders, and the memory and space of their site before coming to a decision.
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The dynamics of satellite galaxies.Zaritsky, Dennis Fabian. January 1991 (has links)
We use the positions and velocities of satellites of our galaxy and of other spiral galaxies to determine the radial mass profile of dark matter halos. We combine our measurement of the velocities of five remote Galactic satellites with published observations of the other Galactic satellites to obtain a complete sample of test particles. We then apply statistical techniques and timing arguments to deduce that the mass of the Galaxy is ≳ 1.3 x 10¹²M(⊙) for standard assumptions and that the halo extends beyond 100 kpc Galactocentric distance. We confirm our result by examining the dynamics of other Local Group galaxies. Subsequently, we expand our study to include nearby (1000 km s⁻¹ < ν(R) < 7000 km s⁻¹) Sb-Sc type galaxies. We use multiaperture spectrometers to conduct a survey for satellite galaxies and are able to double the sample of known satellite galaxies (satellites are defined to be at least eight times fainter than the primary) of isolated unbarred late-type spirals. The homogeneity of the primaries allows us to combine observations of satellites of various primaries and analyze the dynamical properties of the ensemble. The characteristics of this satellite sample (number, radial and azimuthal distribution, luminosity function, orbital characteristics, and contamination) are discussed. Finally, new models of the dynamics of satellite galaxies are developed that include the effects of the cosmological evolution of the halos and do not presume that halos are virialized. These models are used to constrain the mass distribution in which the satellite galaxies orbit. We conclude that only model halos with more than 10¹²M(⊙) within a galactocentric radius of 200 kpc are acceptable (90% confidence limit) for orbits of eccentricity < 0.9. The preferred models (60% confidence limit) are of halos with more than 1.6 x 10¹²M(⊙) within 200 kpc. Halos that formed in a universe with Ω = 1 also fall within the preferred range and have ∼ 3 x 10¹²M(⊙) within 200 kpc. In addition, we infer that the satellites’ orbital eccentricities are typically less than 0.9. These results, in conjunction with the results obtained for the halo of our galaxy, constitute convincing evidence for the existence of large (>200 kpc) and massive (> 10¹²M(⊙), M/L > 80) dark matter halos around isolated unbarred late-type spiral galaxies.
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Neutrino Signals from Dark MatterErkoca, Arif Emre January 2010 (has links)
Large-scale neutrino telescopes will be powerful tools to observe multitude of mysterious phenomena happening in the Universe. The dark matter puzzle is listed as one of them. In this study, indirect detection of dark matter via neutrino signals is presented. The upward muon, the contained muon and the hadronic shower fluxes are calculated, assuming annihilation/decay of the dark matter in the core of the astrophysical objects and in the Galactic center. Direct neutrino production and secondary neutrino production from the decay of Standard Model particles produced in the annihilation/decay of dark matter are studied. The results are contrasted to the ones previously obtained in the literature, illustrating the importance of properly treating muon propagation and energy loss for the upward muon flux. The dependence of the dark matter signals on the density profile, the dark matter mass and the detector threshold are discussed. Different dark matter models (gravitino, Kaluza-Klein and leptophilic) which can account for recent observations of some indirect searches are analyzed regarding their detection in the kilometer size neutrino detectors in the near future. Muon and shower rates and the minimum observation times in order to reach 2σ detection significance are evaluated, with the result suggesting that the optimum cone half angles chosen about the Galactic center are about 10° (50°) for the muon (shower) events. A detailed analysis shows that for the annihilating dark matter models such as the leptophilic and Kaluza-Klein models, upward and contained muon as well as showers yield promising signals for dark matter detection in just a few years of observation, whereas for decaying dark matter models, the same observation times can only be reached with showers. The analytical results for the final fluxes are also obtained as well as parametric forms for the muon and shower fluxes for the dark matter models considered in this study.
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Scalar field cosmologies and their observational implicationsBean, Rachel Esther January 2002 (has links)
No description available.
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Gravitational microlensing of extended objectsColeman, Iain James January 1998 (has links)
No description available.
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Dark Imagery in Women in LoveMoore, James Alton 06 1900 (has links)
This thesis discusses the characters, themes, and imagery in the novel Women in Love written by D.H. Lawrence.
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Interacting dark sectors in cosmologyBuen Abad Najar, Manuel Alejandro 27 November 2018 (has links)
We present two different interacting dark sector models: one in which the dark matter particle is charged under a non-abelian dark gauge group, whose gauge bosons constitute a dark radiation component; and one in which a fraction of the dark matter has efficient number-changing self-interactions that keep it warm. We find that in general the structure formation is slowed down in these models, which addresses a discrepancy in the measurement of the σ8 parameter of large-scale structure. We also perform fits to cosmological data for a generalization of the non-abelian model (in which only a fraction of the dark matter interacts with the dark gauge bosons) and show that it can ease the current experimental tension in the measurement of the Hubble expansion rate H0.
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Cosmological structure formation in decaying dark matter models / 衰變暗物質模型下的宇宙結構演化 / CUHK electronic theses & dissertations collection / Cosmological structure formation in decaying dark matter models / Shuai bian an wu zhi mo xing xia de yu zhou jie gou yan huaJanuary 2014 (has links)
Cheng, Dalong = 衰變暗物質模型下的宇宙結構演化 / 程大龍. / Thesis Ph.D. Chinese University of Hong Kong 2014. / Includes bibliographical references (leaves 105-115). / Abstracts also in Chinese. / Title from PDF title page (viewed on 26, October, 2016). / Cheng, Dalong = Shuai bian an wu zhi mo xing xia de yu zhou jie gou yan hua / Cheng Dalong.
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Nighttime fears in children : origins, frequency, content and severityGordon, Jocelynne E. January 2004 (has links)
Abstract not available
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