Precision cosmology with voids in the final BOSS data. (arXiv:2007.07895v2 [astro-ph.CO] UPDATED)

Precision cosmology with voids in the final BOSS data. (arXiv:2007.07895v2 [astro-ph.CO] UPDATED)
<a href="http://arxiv.org/find/astro-ph/1/au:+Hamaus_N/0/1/0/all/0/1">Nico Hamaus</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Pisani_A/0/1/0/all/0/1">Alice Pisani</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Choi_J/0/1/0/all/0/1">Jin-Ah Choi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Lavaux_G/0/1/0/all/0/1">Guilhem Lavaux</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Wandelt_B/0/1/0/all/0/1">Benjamin D. Wandelt</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Weller_J/0/1/0/all/0/1">Jochen Weller</a>

We report novel cosmological constraints obtained from cosmic voids in the
final BOSS DR12 dataset. They arise from the joint analysis of geometric and
dynamic distortions of average void shapes (i.e., the stacked void-galaxy
cross-correlation function) in redshift space. Our model uses tomographic
deprojection to infer real-space void profiles and self-consistently accounts
for the Alcock-Paczynski (AP) effect and redshift-space distortions (RSD)
without any prior assumptions on cosmology or structure formation. It is
derived from first physical principles and provides an extremely good
description of the data at linear perturbation order. We validate this model
with the help of mock catalogs and apply it to the final BOSS data to constrain
the RSD and AP parameters $f/b$ and $D_AH/c$, where $f$ is the linear growth
rate, $b$ the linear galaxy bias, $D_A$ the comoving angular diameter distance,
$H$ the Hubble rate, and $c$ the speed of light. In addition, we include two
nuisance parameters in our analysis to marginalize over potential systematics.
We obtain $f/b=0.540pm0.091$ and $D_AH/c=0.588pm0.004$ from the full void
sample at a mean redshift of $z=0.51$. In a flat $Lambda$CDM cosmology, this
implies $Omega_mathrm{m}=0.312pm0.020$ for the present-day matter density
parameter. When we use additional information from the survey mocks to
calibrate our model, these constraints improve to $f/b=0.347pm0.023$,
$D_AH/c=0.588pm0.003$, and $Omega_mathrm{m}=0.310pm0.017$. However, we
emphasize that the calibration depends on the specific model of cosmology and
structure formation assumed in the mocks, so the calibrated results should be
considered less robust. Nevertheless, our calibration-independent constraints
are among the tightest of their kind to date, demonstrating the immense
potential of using cosmic voids for cosmology in current and future data.

We report novel cosmological constraints obtained from cosmic voids in the
final BOSS DR12 dataset. They arise from the joint analysis of geometric and
dynamic distortions of average void shapes (i.e., the stacked void-galaxy
cross-correlation function) in redshift space. Our model uses tomographic
deprojection to infer real-space void profiles and self-consistently accounts
for the Alcock-Paczynski (AP) effect and redshift-space distortions (RSD)
without any prior assumptions on cosmology or structure formation. It is
derived from first physical principles and provides an extremely good
description of the data at linear perturbation order. We validate this model
with the help of mock catalogs and apply it to the final BOSS data to constrain
the RSD and AP parameters $f/b$ and $D_AH/c$, where $f$ is the linear growth
rate, $b$ the linear galaxy bias, $D_A$ the comoving angular diameter distance,
$H$ the Hubble rate, and $c$ the speed of light. In addition, we include two
nuisance parameters in our analysis to marginalize over potential systematics.
We obtain $f/b=0.540pm0.091$ and $D_AH/c=0.588pm0.004$ from the full void
sample at a mean redshift of $z=0.51$. In a flat $Lambda$CDM cosmology, this
implies $Omega_mathrm{m}=0.312pm0.020$ for the present-day matter density
parameter. When we use additional information from the survey mocks to
calibrate our model, these constraints improve to $f/b=0.347pm0.023$,
$D_AH/c=0.588pm0.003$, and $Omega_mathrm{m}=0.310pm0.017$. However, we
emphasize that the calibration depends on the specific model of cosmology and
structure formation assumed in the mocks, so the calibrated results should be
considered less robust. Nevertheless, our calibration-independent constraints
are among the tightest of their kind to date, demonstrating the immense
potential of using cosmic voids for cosmology in current and future data.

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