Forecasting the Cosmological Constraints with Anisotropic Baryon
  Acoustic Oscillations from Multipole Expansion
  Baryon acoustic oscillations (BAOs) imprinted in the galaxy power spectrum
can be used as a standard ruler to determine angular diameter distance and
Hubble parameter at high redshift galaxies. Combining redshift distortion
effect which apparently distorts the galaxy clustering pattern, we can also
constrain the growth rate of large-scale structure formation. Usually, future
forecast for constraining these parameters from galaxy redshift surveys has
been made with a full 2D power spectrum characterized as function of wavenumber
$k$ and directional cosine $\mu$ between line-of-sight direction and wave
vector, i.e., $P(k,\mu)$. Here, we apply the multipole expansion to the full 2D
power spectrum, and discuss how much cosmological information can be extracted
from the lower-multipole spectra, taking a proper account of the non-linear
effects on gravitational clustering and redshift distortion. The Fisher matrix
analysis reveals that compared to the analysis with full 2D spectrum, a partial
information from the monopole and quadrupole spectra generally degrades the
constraints by a factor of $\sim1.3$ for each parameter. The additional
information from the hexadecapole spectrum helps to improve the constraints,
which lead to an almost comparable result expected from the full 2D spectrum.
