BICEP1: A CMB polarimeter that observed from 2006-2008
The goal of better understanding the origins of the Universe requires probing this epoch of Inflation directly. The most promising probe of Inflation is the unique signature that the Gravitational Wave Background (GWB) imprints on the polarization of the CMB. The Cosmic Microwave Background (CMB) provides three strong but circumstantial pieces of evidence that the visible Universe was created by the superluminal inflation of a tiny volume of space: near isotropy of the horizon, flatness of space, phase-synchronicity of acoustic oscillations in the early universe.
The amplitude of this signature depends on the energy-scale of Inflation. If the energy scale is typical of Grand Unification Theory (GUT, 10^16 GeV), the signature may be detectable. The signature of the GWB-induced polarization is expected to be less than an rms amplitude of ~300 nK of the CMB; more than two orders of magnitude below the amplitude of the temperature anisotropies that have only recently been resolved over the full-sky by the Planck satellite. Detection will require only modest angular resolution (~ 1 deg.), but will require long integration (~3 years) on a restricted (~3%) and contiguous patch of sky. BICEP1 is a uniquely capable instrument for detecting the signature of the Gravitational Wave Background (GWB). The six-month nights, extremely dry and stable weather, and the precise rotation of the sky about the zenith make South Pole Station the ideal terrestrial site for this ambitious project.