Cosmic distance determination from photometric redshift samples using BAO peaks only. (arXiv:1903.09651v2 [astro-ph.CO] UPDATED)
<a href="http://arxiv.org/find/astro-ph/1/au:+Sridhar_S/0/1/0/all/0/1">Srivatsan Sridhar</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Song_Y/0/1/0/all/0/1">Yong-Seon Song</a>
The galaxy distributions along the line-of-sight are significantly
contaminated by the uncertainty on redshift measurements obtained through
multiband photometry, which makes it difficult to get cosmic distance
information measured from baryon acoustic oscillations, or growth functions
probed by redshift distortions. We investigate the propagation of the
uncertainties into large scale clustering by exploiting all known estimators,
and propose the wedge approach as a promising analysis tool to extract cosmic
distance information still remaining in the photometric galaxy samples. We test
our method using simulated galaxy maps with photometric uncertainties of
$sigma_{0} =left(0.01, 0.02, 0.03right)$. The measured anisotropy
correlation function $xi$ is binned into the radial direction of $s$ and the
angular direction of $mu$, and the variations of $xi(s,mu)$ with
perpendicular and radial cosmic distance measures of $D_A$ and $H^{-1}$ are
theoretically estimated by an improved RSD model. Although the radial cosmic
distance $H^{-1}$ is unable to be probed from any of the three photometric
galaxy samples, the perpendicular component of $D_A$ is verified to be
accurately measured even after the full marginalisation of $H^{-1}$. We measure
$D_A$ with approximately 6% precision which is nearly equivalent to what we can
expect from spectroscopic DR12 CMASS galaxy samples.
The galaxy distributions along the line-of-sight are significantly
contaminated by the uncertainty on redshift measurements obtained through
multiband photometry, which makes it difficult to get cosmic distance
information measured from baryon acoustic oscillations, or growth functions
probed by redshift distortions. We investigate the propagation of the
uncertainties into large scale clustering by exploiting all known estimators,
and propose the wedge approach as a promising analysis tool to extract cosmic
distance information still remaining in the photometric galaxy samples. We test
our method using simulated galaxy maps with photometric uncertainties of
$sigma_{0} =left(0.01, 0.02, 0.03right)$. The measured anisotropy
correlation function $xi$ is binned into the radial direction of $s$ and the
angular direction of $mu$, and the variations of $xi(s,mu)$ with
perpendicular and radial cosmic distance measures of $D_A$ and $H^{-1}$ are
theoretically estimated by an improved RSD model. Although the radial cosmic
distance $H^{-1}$ is unable to be probed from any of the three photometric
galaxy samples, the perpendicular component of $D_A$ is verified to be
accurately measured even after the full marginalisation of $H^{-1}$. We measure
$D_A$ with approximately 6% precision which is nearly equivalent to what we can
expect from spectroscopic DR12 CMASS galaxy samples.
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