English
Related papers

Related papers: A new direction for dark matter research: intermed…

200 papers

The present day mass spectrum for dark matter compact objects is calculated based on the assumption that a uniform population of PBHs was created at a definite red-shift, and that the mass spectrum evolved as a result of gravitational…

General Relativity and Quantum Cosmology · Physics 2018-05-29 G. Chapline , J. Barbieri

The main aim of microlensing experiments is to evaluate the mean mass of massive compact halo objects (MACHOs) and the mass fraction of the Galactic halo made by this type of dark matter. Statistical analysis shows that by considering a…

Astrophysics · Physics 2009-11-10 Sohrab Rahvar

The aim of this paper is to present the case that stellar mass primordial black holes make up the dark matter component of the Universe. A near critical density of compact bodies implies that most lines of sight will be gravitationally…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-21 M. R. S. Hawkins

I will begin by reviewing the evidence for Dark Matter in the Universe, as well as the candidates for dark matter. At most 20% of the dark matter in galaxies can be in the form of MACHOs (Massive Compact Halo Objects); the remainder appears…

Astrophysics · Physics 2008-11-26 Katherine Freese

We present the analysis on our new limits of the dark matter (DM) halo consisting of primordial black holes (PBHs) or massive compact halo objects (MACHOs). We present a search of the first two years of publicly available Kepler mission…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Kim Griest , Agnieszka M. Cieplak , Matthew J. Lehner

One of the most important problems in astrophysics concerns the nature of the dark matter in galactic halos, whose presence is implied mainly by the observed flat rotation curves in spiral galaxies. In the framework of a baryonic scenario…

Astrophysics · Physics 2007-05-23 Philippe Jetzer

The MACHO project is a search for dark matter in the form of massive compact halo objects (MACHOs). The project has photometrically monitored tens of millions of stars in the Large Magellanic Cloud (LMC), Small Magellanic Cloud (SMC), and…

Most of the mass density in the Universe---and in the halo of our own galaxy---exists in the form of dark matter. Overall, the contribution of luminous matter (in stars) to the mass density of the Universe is less than 1\%; primordial…

Astrophysics · Physics 2009-09-25 Michael S. Turner

We present final results from the first phase of the EROS search for gravitational microlensing of stars in the Magellanic Clouds by unseen deflectors (machos: MAssive Compact Halo Objects). The search is sensitive to events with time…

Stars in globular clusters can act either as sources for MACHOs (Massive Astrophysical Compact Halo Objects) located along the line of sight or as lenses for more distant background stars. Although the expected rate of microlensing events…

Astrophysics · Physics 2007-05-23 P. Jetzer , M. Strässle , U. Wandeler

Paczy\'nski (1986) suggested that ``dark" objects in the halo of our Galaxy could enhance the luminosity of foreground stars, acting as gravitational microlenses. Such events has been recently reported by different collaborations. We assume…

Astrophysics · Physics 2007-05-23 Sergio Campana

The MACHO collaboration reports on the analysis of our first year LMC data, 9.5 million light curves with an average of 235 observations each. Automated selection procedures give 3 events consistent with microlensing. We evaluate our…

We propose that the recently reported MACHO/EROS events correspond to gravitational amplification by dark clouds rather than compact objects. These clouds must be very dense with $M\sim 0.1 ~M_\odot$ and $R\la 10^{14}~{\rm cm}$. In all…

Astrophysics · Physics 2009-10-22 Richard N. Henriksen , Lawrence M. Widrow

A simple interpretation of the more than dozen microlensing events seen in the direction of the LMC is a halo population of MACHOs which accounts for about half of the mass of the Galaxy. Such an interpretation is not without its problems,…

Astrophysics · Physics 2009-10-30 Evalyn I. Gates , Geza Gyuk , Gilbert P. Holder , Michael S. Turner

Observations by the MACHO collaboration indicate that a significant fraction of the galactic halo dark matter may be in form of compact objects with masses $M\sim 0.5M_{\odot}$. Identification of these objects as red or white dwarfs is…

Astrophysics · Physics 2009-10-30 Karsten Jedamzik

A significant fraction of non-baryonic or baryonic dark matter in galactic halos may consist of MASsive Compact Objects (MASCOs) with mass M=10^{1-4}M_{sun}. Possible candidates for such compact objects include primordial black holes or…

Astrophysics · Physics 2009-11-07 Kaiki Taro Inoue , Masashi Chiba

One of the possible astrophysical solutions to the galactic dark matter problem is the presence of a significant amount of ``dark'' compact objects (MACHOs) in galactic dark matter halos. MEGA (Microlensing Exploration of the Galaxy and…

The MACHO Project is a search for dark matter in the form of massive compact halo objects (Machos). Photometric monitoring of millions of stars in the Large Magellanic Cloud (LMC), Small Magellanic Cloud (SMC), and Galactic bulge is used to…

Using eight dark matter haloes extracted from fully-self consistent cosmological N-body simulations, we perform microlensing experiments. A hypothetical observer is placed at a distance of 8.5 kpc from the centre of the halo measuring…

Astrophysics · Physics 2009-11-11 Janne Holopainen , Chris Flynn , Alexander Knebe , Stuart P. Gill , Brad K. Gibson

The idea that dark matter can be made of intermediate-mass primordial black holes in the $10M_\odot \lesssim M \lesssim 200M_\odot$ range has recently been reconsidered, particularly in the light of the detection of gravitational waves by…

Astrophysics of Galaxies · Physics 2017-02-22 E. Mediavilla , J. JimÉnez-Vicente , J. A. MuÑoz , H. Vives-Arias , J. CalderÓn-Infante