Archives 2009Accounting for the ARCADE-2 Extragalactic Radio Background
The ARCADE-2 observations show that the extragalactic radio background radiation is several times brighter than was expected - this puzzle has recently been investigated by KIPAC researchers Jack Singal (an ARCADE-2 member), Lukasz Stawarz, Vahe Petrosian and long-term visitor Andrew Lawrence. As with so many other astronomical survey detections, the physical explanations of the observed phenomenon have far-reaching consequences.Fermi's Pulsars: Tev Electron-Positron Accelerators in the Gamma-Ray Sky
The Fermi LAT has discovered a number of nearby, energetic yet radio-quiet pulsars: whether they are seen as laboratories for fundamental physics, or as potential contaminants of the dark matter search, the information provided by Fermi is invaluable.Dark Matter Searches with Fermi: Spectral Lines and Dwarf Spheroidal Galaxies
The Fermi LAT team at KIPAC have begun looking for dark matter annhilation and decay where the signal-to-background is highest - no detections yet, but they are already ruling out some interesting models...
Precision Dark Energy Measurement with the Gravitational Lens B1608+656
In the time when all experimental probes of dark energy are limited by systematic errors, diversification will be vital. The cosmology community is agreed on the necessity of approaching the problem from multiple directions, and an international team of researchers including Roger Blandford and Phil Marshall at KIPAC have been exploring a new one: strong gravitational lenses.Measuring the Polarization of the Cosmic Microwave Background
KIPAC researchers are playing leading roles in probing the physics of the early universe by making measurements of the Cosmic Microwave Background radiation (CMB).Dark Energy from the Growth of Structure: The Cluster XLF
Mantz, Allen, Rapetti et al use the X-ray luminosity function of clusters of galaxies to confirm the effects of Dark Energy on the growth of cosmic structure, and to help provide some of the tightest constraints on the equation of state parameter to date.