Probing Primordial Features with the Stochastic Gravitational Wave
  Background
  The stochastic gravitational wave background (SGWB) offers a new opportunity
to observe signals of primordial features from inflationary models. We study
their detectability with future space-based gravitational waves experiments,
focusing our analysis on the frequency range of the LISA mission. We compute
gravitational wave spectra from primordial features by exploring the parameter
space of a two-field inflation model capable of generating different classes of
features. Fine-tuning in scales and amplitudes is necessary for these signals
to fall in the observational windows. Once they show up, several classes of
frequency-dependent oscillatory signals, characteristic of different underlying
inflationary physics, may be distinguished and the SGWB provides a window on
dynamics of the primordial universe independent of cosmic microwave background
and large-scale structure. To connect with future experimental data, we discuss
two approaches of how the results may be applied to data analyses. First, we
discuss the possibility of reconstructing the signal with LISA, which requires
a high signal-to-noise ratio. The second more sensitive approach is to apply
templates representing the spectra as estimators. For the latter purpose, we
derive templates that can accurately capture the spectral features of several
classes of feature signals and compare them with the SGWB produced by other
physical mechanisms.
