Can MACHOs probe the shape of the galaxy halo?

Joshua Frieman, Roman Scoccimarro

    Research output: Contribution to journalArticle

    Abstract

    Microlensing searches in our galaxy have recently discovered several candidates in the direction of the Large Magellanic Cloud (LMC). We study the prospects for such searches to yield useful information about the flattening of the Galaxy dark matter halo, using a self-consistent oblate halo model and allowing for the possibility of misalignment between the disk and halo symmetry axes. The microlensing optical depth for the LMC, τ(LMC), depends sensitively on the disk-halo tilt angle in the Milky Way, as does the ratio τ(SMC)/ τ(LMC). If the tilt angle is as large as 30°, a much larger spread in values for τ(LMC) is consistent with rotation curve constraints than previously thought. Disk-halo tilt and halo flattening do not significantly affect the MACHO masses inferred from event durations.

    Original languageEnglish (US)
    JournalAstrophysical Journal
    Volume431
    Issue number1 PART 2
    StatePublished - Aug 10 1994

    Fingerprint

    massive compact halo objects
    tilt
    Magellanic clouds
    halos
    probe
    galaxies
    probes
    flattening
    optical depth
    symmetry
    misalignment
    optical thickness
    dark matter
    curves

    Keywords

    • Dark matter
    • Gravitational lensing
    • Magellanic Clouds

    ASJC Scopus subject areas

    • Space and Planetary Science

    Cite this

    Frieman, J., & Scoccimarro, R. (1994). Can MACHOs probe the shape of the galaxy halo? Astrophysical Journal, 431(1 PART 2).

    Can MACHOs probe the shape of the galaxy halo? / Frieman, Joshua; Scoccimarro, Roman.

    In: Astrophysical Journal, Vol. 431, No. 1 PART 2, 10.08.1994.

    Research output: Contribution to journalArticle

    Frieman, J & Scoccimarro, R 1994, 'Can MACHOs probe the shape of the galaxy halo?', Astrophysical Journal, vol. 431, no. 1 PART 2.
    Frieman J, Scoccimarro R. Can MACHOs probe the shape of the galaxy halo? Astrophysical Journal. 1994 Aug 10;431(1 PART 2).
    Frieman, Joshua ; Scoccimarro, Roman. / Can MACHOs probe the shape of the galaxy halo?. In: Astrophysical Journal. 1994 ; Vol. 431, No. 1 PART 2.
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