• Login
    View Item 
    •   Home
    • UA Graduate and Undergraduate Research
    • UA Theses and Dissertations
    • Dissertations
    • View Item
    •   Home
    • UA Graduate and Undergraduate Research
    • UA Theses and Dissertations
    • Dissertations
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

    All of UA Campus RepositoryCommunitiesTitleAuthorsIssue DateSubmit DateSubjectsPublisherJournalThis CollectionTitleAuthorsIssue DateSubmit DateSubjectsPublisherJournal

    My Account

    LoginRegister

    About

    AboutUA Faculty PublicationsUA DissertationsUA Master's ThesesUA Honors ThesesUA PressUA YearbooksUA CatalogsUA Libraries

    Statistics

    Most Popular ItemsStatistics by CountryMost Popular Authors

    The collisional and dynamical evolution of the main belt, NEA and TNO populations

    • CSV
    • RefMan
    • EndNote
    • BibTex
    • RefWorks
    Thumbnail
    Name:
    azu_td_3131625_sip1_m.pdf
    Size:
    7.701Mb
    Format:
    PDF
    Download
    Author
    O'Brien, David Patrick
    Issue Date
    2004
    Keywords
    Physics, Astronomy and Astrophysics.
    Advisor
    Greenberg, Richard J.
    
    Metadata
    Show full item record
    Publisher
    The University of Arizona.
    Rights
    Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
    Abstract
    The size distribution of main-belt of asteroids is determined primarily by collisional processes. Large asteroids break up and form smaller asteroids in a collisional cascade, with the outcome controlled by the strength-vs.-size relationship for asteroids. We develop an analytical model that incorporates size-dependent strength and is able to reproduce the general features of the main-belt size distribution. In addition to collisional processes, the non-collisional removal of asteroids from the main belt (and their insertion into the near-Earth asteroid (NEA) population) is critical, and involves several effects: Strong resonances increase the orbital eccentricity of asteroids and cause them to enter the inner planet region; Chaotic diffusion by numerous weak resonances causes a slow leak of asteroids into the Mars- and Earth-crossing populations; And the Yarkovsky effect, a radiation force on asteroids, is the primary process that drives asteroids into these resonant escape routes. Yarkovsky drift is size-dependent and can potentially modify the main-belt size distribution. The NEA size distribution is primarily determined by its source, the main belt population, and by the size-dependent processes that deliver bodies from the main belt. All of these processes are simulated in a numerical collisional evolution model that incorporates removal by non-collisional processes. This model yields the strength-vs.-size relationship for main-belt asteroids and the non-collisional removal rates from the main belt required for consistency with the observed main-belt and NEA size distributions. Our results are consistent with other estimates of strength and removal rates, and fit a wide range of constraints, such as the number of observed asteroid families, the preserved basaltic crust of Vesta, the cosmic ray exposure ages of meteorites, and the observed cratering records on asteroids. Finally, our analytical and numerical models are applied to the collisional evolution of the trans-Neptunian objects (TNOs). We show that the TNO population likely started with a shallow initial size distribution, and that bodies ≳ 10 km in diameter are likely not in a collisional steady state. In addition, we show that the population of bodies in the TNO region below the size range of recent observational surveys is likely large enough to explain the observed numbers of Jupiter-family comets.
    Type
    text
    Dissertation-Reproduction (electronic)
    Degree Name
    Ph.D.
    Degree Level
    doctoral
    Degree Program
    Graduate College
    Planetary Sciences
    Degree Grantor
    University of Arizona
    Collections
    Dissertations

    entitlement

     
    The University of Arizona Libraries | 1510 E. University Blvd. | Tucson, AZ 85721-0055
    Tel 520-621-6442 | repository@u.library.arizona.edu
    DSpace software copyright © 2002-2017  DuraSpace
    Quick Guide | Contact Us | Send Feedback
    Open Repository is a service operated by 
    Atmire NV
     

    Export search results

    The export option will allow you to export the current search results of the entered query to a file. Different formats are available for download. To export the items, click on the button corresponding with the preferred download format.

    By default, clicking on the export buttons will result in a download of the allowed maximum amount of items.

    To select a subset of the search results, click "Selective Export" button and make a selection of the items you want to export. The amount of items that can be exported at once is similarly restricted as the full export.

    After making a selection, click one of the export format buttons. The amount of items that will be exported is indicated in the bubble next to export format.