자료유형 | 학위논문 |
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서명/저자사항 | Astrophysical Signals of Physics Beyond the Standard Model. |
개인저자 | Taki, Anna-Maria. |
단체저자명 | New York University. Physics. |
발행사항 | [S.l.]: New York University., 2019. |
발행사항 | Ann Arbor: ProQuest Dissertations & Theses, 2019. |
형태사항 | 165 p. |
기본자료 저록 | Dissertations Abstracts International 81-06B. Dissertation Abstract International |
ISBN | 9781392864692 |
학위논문주기 | Thesis (Ph.D.)--New York University, 2019. |
일반주기 |
Source: Dissertations Abstracts International, Volume: 81-06, Section: B.
Advisor: Weiner, Neal. |
이용제한사항 | This item must not be sold to any third party vendors.This item must not be added to any third party search indexes. |
요약 | The questions revolving around dark matter have challenged our understanding of the fundamental structure of the Universe ever since its existence was inferred from astronomical observations.As dark matter structures move in the Milky Way halo, they can act as lenses and distort the trajectories of stars. The monitoring of the stellar motions can then yield information about the dark matter. Unveiling the nature of this elusive type of matter through these astrometric signatures is a daunting undertaking, but through the exploration of new data sets collected at terrestrial and astrophysical laboratories, this enterprise is geared to probe novel ideas and broaden our understanding of the cosmos.The projects that compose this dissertation are meant to serve this purpose via the development of novel astrometric lensing techniques that leverage catalogs of high precision data produced by ongoing astrometric missions.In the first part of this thesis, we introduce halometry as one of the prominent paths to follow in order to study the properties of non-luminous objects in our galaxy. This can be realized via time-variable, weak gravitational lensing of stars and other background light sources. In the dawn of precision astrometry, current astrometric surveys such as {\\it Gaia} offer unprecedented precision plus an enormous number of cataloged observations. Time-domain, high-statistics, precision astrometry thus can serve as a new and sensitive probe for revealing the existence of dark objects in our galaxy.Taking into account that there is a plethora of masses and densities that could in principle be exhibited by dark matter clumps, there is no single method designed to test all possible cases. Therefore, to address different scenarios, we proposed signal observables that fall into three categories --- multi-blips, templates, and correlations. These tests are designed to capture correlated effects in the motion of many background light sources, leading us to employ statistical methods to extract features collectively from the entire population of events. The detection principles and sensitivity forecasts outlined in this work present us with new opportunities to explore the small-scale structure of our universe and the outer regions of the Solar System.In the second part of this thesis, we present a case study of a template analysis detection scheme, through which we wish to impose the first constraints on dark matter halo substructure using time-domain weak gravitational lensing. Though a spatially extended lens would in practice suppress a lensing signal, the potentially large number of sources behind it could enhance it. Such a large number of sources can lead to correlated effects in the motion of luminous background sources that could be teased out with high statistics. In particular, we introduce a lens velocity test statistic designed to contrast the observed velocities of background luminous sources with an expected lens-induced velocity field, for a lens population of certain density profile, velocity, and angular size along the line of sight in that location on the sky.This template test statistic has motivated the development of novel statistical analysis techniques, which will allow us to make robust measurements of the abundance of dark compact objects in the Milky Way. |
일반주제명 | Particle physics. |
언어 | 영어 |
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