Results 31 to 40 of about 73,795 (320)
Interstellar titanium in the galactic halo [PDF]
The Astrophysical Journal, 1995 We present observations of Ti~II~$ 3384$ absorption towards 15 distant stars in the Galactic halo and the Magellanic Clouds. These new data extend existing surveys of the distribution of Ti$^+$ to larger distances from the plane of the Galaxy than sampled previously, allowing the scale height of titanium to be determined for the first time.
Max Pettini, Keith Lipman
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A new look at microlensing limits on dark matter in the Galactic halo [PDF]
A&A 575, A107 (2015), 2015 The motivation for this paper is to review the limits set on the MACHO content of the Galactic halo by microlensing experiments in the direction of the Large Magellanic Cloud. This has been prompted by recent measurements of the Galactic rotation curve, which suggest that the limits have been biassed by the assumption of an over-massive halo. The paper
arxiv +1 more source
A Catalog of Distance Determinations for the LAMOST DR8 K Giants in the Galactic Halo
The Astronomical Journal, 2023 We present a catalog of distances for 19,544 K giants drawn from Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) DR8. Most of them are located in the halo of the Milky Way up to ∼120 kpc.
Lan Zhang +6 more
doaj +1 more source
European Physical Journal C: Particles and Fields, 2022 Dark matter (DM) annihilation in the galactic halo can be enhanced relative to that in the early Universe due to the Breit–Wigner enhancement, if the DM particles annihilate through a narrow resonance.
Yu-Chen Ding +3 more
doaj +1 more source
FOSSILs in the Galactic Halo [PDF]
Proceedings of the International Astronomical Union, 2018 AbstractWe use a matched filter to detect compact groups of old, metal-poor stars that we term FOSSILs (Fragments of Old Stellar Systems in Limbo). With size scales on the order of 10 arcminutes, distances ranging from 2 to 200 kpc, and memberships ranging from a handful to several dozen stars, these FOSSILs stand out from the surrounding field and are
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Magnetic Reconnection Triggered by the Parker Instability in the Galaxy: Two-Dimensional Numerical Magnetohydrodynamic Simulations and Application to the Origin of X-Ray Gas in the Galactic Halo [PDF]
Astrophys.J. 582 (2003) 215-229, 2002 We propose the Galactic flare model for the origin of the X-ray gas in the Galactic halo. For this purpose, we examine the magnetic reconnection triggered by Parker instability (magnetic buoyancy instability), by performing the two-dimensional resistive numerical magnetohydrodynamic simulations.
arxiv +1 more source
The asymmetric structure of the Galactic halo [PDF]
Monthly Notices of the Royal Astronomical Society, 2006 17 pages, 7 figures, 5 tables, MNRAS ...
J. Y. Hu, Yong Xu, Licai Deng
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Fireballs in the Galactic Halo and $γ$-Ray Bursts [PDF]
Astrophys.J. 403 (1993) L67, 1992 If gamma ray burst sources are in the galactic halo they inevitably involve a creation of an opaque pair plasma fireball, just like in cosmological sources. We find that the typical physical conditions in a galactic halo fireball are: optical depth $\ap 10^8$, thermal energy $\ap 100 KeV$, maximal relativstic expansion $\G \ap 300 $ and a maximal ...
arxiv +1 more source
Parameters of Six Selected Galactic Potential Models
Open Astronomy, 2017 This paper is devoted to the refinement of the parameters of the six three-component (bulge, disk, halo) axisymmetric Galactic gravitational potential models on the basis of modern data on circular velocities of Galactic objects located at distances up ...
Bajkova Anisa, Bobylev Vadim
doaj +1 more source
Milli-magnetic monopole dark matter and the survival of galactic magnetic fields
Journal of High Energy Physics, 2022 Dark sectors with Abelian gauge symmetries can interact with ordinary matter via kinetic mixing. In such scenarios, magnetic monopoles of a broken dark U(1) will appear in our sector as confined milli-magnetically charged objects under ordinary ...
Michael L. Graesser +2 more
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