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Showing 1 to 12 of 12 for “"Be stars"”.

  1. Nitrogen Abundances in Early-Type Be Stars

    Ahmed, AhmedThe University of Western Ontario2015

    A sample of 26 Be stars from the Magnetism in Massive Stars (MiMeS) spectroscopic survey are analyzed for their photospheric nitrogen abundances in an effort to detect rotational mixing in the Be stars. Be stars are massive stars, between 3 and 20 times the mass of the Sun, that are surrounded by a …

    uwo Repository record

  2. The Inner Gaseous Disks Of Herbig Be Stars

    Patel, ParshatiThe University of Western Ontario2016

    Herbig Ae/Be stars are intermediate mass (~2 to 20Msun) pre-main sequence stars that inherit a circumstellar disk of dust and gas from their formation phase. The region of this disk closest to the star is entirely gaseous because dust evaporates at the high temperatures there, and this gaseous …

    uwo Repository record

  3. Star-Disk Interaction in Herbig Ae/Be Stars

    Speights, Christa

    clemson Repository record

  4. Differential polarisation studies of the deffuse interstellar band and Be stars

    Dinshaw, NadineUniversity of British Columbia1992

    … polarisation analyser has been designed and built at the Dominion Astrophysical Observatory specifically for the 1.83-m telescope. It is mounted before the Cassegrain spectrograph entrance, and is capable of providing spectropolarime-try at the full (--, 0.15 A) resolution …

    ubc Repository record

  5. Parameterizing the Dust Around Herbig Ae/Be Stars: Multiwavelength Imaging, Radiative Transfer Modeling, and Near-Infrared Instrumentation

    Doering, Ryan LeeUniversity of Illinois at Urbana-Champaign2015

    … available for observations of Herbig Ae/Be stars, I have participated in the development of the WIYN High Resolution Infrared Camera. The instrument operates in the near-infrared (∼0.8 -- 2.5 mum), includes 13 filters, and has a pixel size of ∼0.1&inches;, resulting in a field of …

    uiuc Repository record

  6. Understanding the Star -Forming Environment in Stellar Clusters

    Wang, ShiyaUniversity of Illinois at Urbana-Champaign2015

    … for the formation of low-mass cluster members. Embedded, young, and intermediate-mass stellar clusters around Herbig Ae/Be stars are sampled. Mid- and near-infrared observations identifying young stars and millimeter interferometric observations probing dense molecular gas and dust …

    uiuc Repository record

  7. Fast Stars in the Milky Way

    Boubert, Douglas PhilipUniversity of Cambridge2018

    I present a comprehensive investigation of fast stars in the Milky Way, from brisk disc stars to stars escaping the Galaxy. My thesis is that fast stars are the smoking guns of extreme stellar collisions and explosions, and so can act as an intermediary to studying these theoretically-unconquered …

    cambridge Repository record

  8. Photometric monitoring of early type emission line stars

    Davies, John KeithLancashire Polytechnic1988

    … MNQ) photometry of early type, emission line, stars is described. Particular emphasis is placed on observations of suspected pre-main-sequence objects such as Herbig Ae/Be stars. The observations, together with data from the IRAS point source catalogue, are analysed to probe the circumstellar …

    cent-lancashire Repository record

  9. High resolution studies of early type emission line stars

    Wheelwright, Hugh EricUniversity of Leeds2010

    … to separate the spectra of unresolved Herbig Ae/Be binary systems. The separated spectra allow the mass ratio of the systems to be established. The separation and mass ratio distribution of the systems suggest that they form via disk fragmentation. To test this conclusion, disk and binary …

    whiterose Repository record

  10. Be binary stars with hot, compact companions

    Maintz, MonikaUniversität Heidelberg

    … the importance of close binary evolution for Be star formation was investigated. The Be star 59 Cygni was confirmed to be an evolved binary with a sdO companion. The companion was confirmed by a weak helium II absorption. Orbital elements and stellar masses were determined. In the spectrum of …

    heid-diss Repository record

  11. Spectroscopic and photometric investigation of selected hot stars

    Oplištilová, AlžbětaUniverzita Karlova, Matematicko-fyzikální fakulta2021

    … složky. Omega Canis Majoris patří mezi Be hvězdy, u kterých není zcela objasněn původ a formování plynné obálky, tzv. závoje. V práci jsou pomocí matemat- ických technik a programů na modelování (PHOEBE 1) určeny vlastnosti delty Orionis A a je ukázáno, že by mohla být pravdivá domněnka …

    charles-prague Repository record

  12. How circumstellar discs affect mass accretion in Be X-ray binaries

    Monageng, Itumeleng MatubaDepartment of Astronomy2014

    … optical spectroscopic monitoring of Galactic Be X-ray binaries (BeXBs) is performed using the Liverpool Telescope and the Southern African Large Telescope on northern and southern objects, respectively. Be disc size variations are presented to investigate their influence on mass accretion …

    cape-town Repository record