ar X iv : a st ro - p h / 99 03 01 1 v 1 1 M ar 1 99 9 Density Distribution and Shape of Galactic Dark Halo Can be Determined by Low Frequency Gravitational Waves ?
نویسندگان
چکیده
Under the assumption that the Milky Way’s dark halo consists of primordial black hole MACHOs (PBHMACHOs), the mass density of the halo can be measured by the low frequency gravitational waves (10 Hz ∼< νgw ∼< 10 Hz) from PBHMACHO binaries whose fraction is ∼ 10. We find that ten years observation by LISA will detect ∼ 700 PBHMACHO binaries and enable us to determine the power index of the density profile within 10% (20%) and the core radius within 25% (50%) in about 90% (99%) confidence level, respectively. The axial ratios of the halo may also be determined within ∼ 10%. LISA and OMEGA may give us an unique observational method to determine the density profile and the shape of the dark halo to open a new field of observational astronomy. Subject headings: black hole physics — dark matter — Galaxy: halo — Galaxy: structure — gravitation — gravitational lensing
منابع مشابه
ar X iv : a st ro - p h / 01 06 39 2 v 2 1 9 Ju l 2 00 1 White Dwarfs : Contributors and Tracers of the Galactic Dark – Matter Halo
We examine the claim by Oppenheimer et al. (2001) that the local halo density of white dwarfs is an order of magnitude higher than previously thought. As it stands, the observational data support the presence of a kinematically distinct population of halo white dwarfs at the >99% confidence level. A maximum-likelihood analysis gives a radial velocity dispersion a of σ h U =150 +80 −40 km s −1 a...
متن کاملar X iv : a st ro - p h / 99 03 01 3 v 1 1 M ar 1 99 9 Galactic distribution of 1 . 275 MeV emission from ONe novae
Modelisations of galactic 1.275 MeV emission produced by the decay 22 Na have been performed for several frequency-spatial distributions of ONe novae. Recent results of nova rates and their distributions in our Galaxy have been used. These modelisations allow to estimate the lower-limit of the 22 Na mass ejected per ONe novae detectable with the future spectrometer (SPI) of the INTEGRAL observa...
متن کاملar X iv : a st ro - p h / 01 06 39 2 v 1 2 1 Ju n 20 01 White Dwarfs : Contributors and Tracers of the Galactic Dark – Matter Halo
We examine the claim by Oppenheimer et al. (2001) that the local halo density of white dwarfs is an order of magnitude higher than previously thought. As it stands, the observational data support the presence of a kinematically distinct population of halo white dwarfs at the >99% confidence level a. A maximum-likelihood analysis gives a radial velocity dispersion of σ h U =160
متن کاملar X iv : a st ro - p h / 94 11 03 8 v 1 9 N ov 1 99 4 THE PARTICLE - AND ASTRO - PHYSICS OF DARK MATTER ⋆
We review some recent determinations of the amount of dark matter on galactic, cluster, and large scales, noting some puzzles and their possible resolutions. We discuss the interpretation of big bang nucleosynthesis for dark matter, and then review the motivation for and basic physics of several dark matter candidates, including Machos, Wimps, axions, and neutrinos. Finally, we discuss how the ...
متن کاملar X iv : a st ro - p h / 05 01 13 3 v 2 2 7 M ay 2 00 5 1 Ultrahigh energy cosmic rays from collisional annihilation revisited
We re-examine collisional annihilation of superheavy dark matter particles in dark matter density spikes in the galactic halo as a possible source of ultrahigh energy cosmic rays. We estimate the possible flux in a way that does not depend on detailed assumptions about the density profiles of dark matter clumps. The result confirms that collisional annihilation is compatible with annihilation c...
متن کامل