  BigBOSS is a Stage IV ground-based dark energy experiment to study baryon
acoustic oscillations (BAO) and the growth of structure with a wide-area galaxy
and quasar redshift survey over 14,000 square degrees. It has been
conditionally accepted by NOAO in response to a call for major new
instrumentation and a high-impact science program for the 4-m Mayall telescope
at Kitt Peak. The BigBOSS instrument is a robotically-actuated, fiber-fed
spectrograph capable of taking 5000 simultaneous spectra over a wavelength
range from 340 nm to 1060 nm, with a resolution R = 3000-4800.
  Using data from imaging surveys that are already underway, spectroscopic
targets are selected that trace the underlying dark matter distribution. In
particular, targets include luminous red galaxies (LRGs) up to z = 1.0,
extending the BOSS LRG survey in both redshift and survey area. To probe the
universe out to even higher redshift, BigBOSS will target bright [OII] emission
line galaxies (ELGs) up to z = 1.7. In total, 20 million galaxy redshifts are
obtained to measure the BAO feature, trace the matter power spectrum at smaller
scales, and detect redshift space distortions. BigBOSS will provide additional
constraints on early dark energy and on the curvature of the universe by
measuring the Ly-alpha forest in the spectra of over 600,000 2.2 < z < 3.5
quasars.
  BigBOSS galaxy BAO measurements combined with an analysis of the broadband
power, including the Ly-alpha forest in BigBOSS quasar spectra, achieves a FOM
of 395 with Planck plus Stage III priors. This FOM is based on conservative
assumptions for the analysis of broad band power (kmax = 0.15), and could grow
to over 600 if current work allows us to push the analysis to higher wave
numbers (kmax = 0.3). BigBOSS will also place constraints on theories of
modified gravity and inflation, and will measure the sum of neutrino masses to
0.024 eV accuracy.
