A New Probe of Dark Matter and High-Energy Universe Using Microlensing

Details A New Probe of Dark Matter and High-Energy Universe Using Microlensing A New Probe of Dark Matter and High-Energy Universe Using Microlensing

2009-08-05

arxiv.org/abs/0908.0735v2

Astronomy and Astrophysics

Astrophysics

Cosmology and Extragalactic Astrophysics

9 pages, 3 figure, submitted to ApJ (v2 corrects only a typo in arXiv abstract)

Scientific paper

We propose the existence of ultracompact minihalos as a new type of massive compact halo object (MACHO) and suggest an observational test to discover them. These new MACHOs are a powerful probe into the nature of dark matter and physics in the high energy Universe. Non-Gaussian energy-density fluctuations produced at phase transitions (e.g., QCD) or by features in the inflaton potential can trigger primordial black hole (PBH) formation if their amplitudes are delta > 30%. We show that a PBH accumulates over time a sufficiently massive and compact minihalo to be able to modify or dominate its microlensing magnification light curve. Perturbations of amplitude 0.03% < delta < 30% are too small to form PBHs, but can nonetheless seed the growth of ultracompact minihalos. Thus, the likelihood of ultracompact minihalos as MACHOs is greater than that of PBHs. In addition, depending on their mass, they may be sites of formation of the first PopIII stars. Ultracompact minihalos and PBHs produce a microlensing light curve that can be distinguished from that of a "point-like" object if high-quality photometric data are taken for a sufficiently long time after the peak of the magnification event. This enables them to be detected below the stellar-lensing "background" toward both the Magellanic Clouds and the Galactic bulge.

Affiliated with

Also associated with

No associations

Rating

A New Probe of Dark Matter and High-Energy Universe Using Microlensing does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with A New Probe of Dark Matter and High-Energy Universe Using Microlensing, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A New Probe of Dark Matter and High-Energy Universe Using Microlensing will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-705338