%0 Generic %1 nadathur2019beyond %A Nadathur, Seshadri %A Carter, Paul M. %A Percival, Will J. %A Winther, Hans A. %A Bautista, Julian %D 2019 %K library %T Beyond BAO: improving cosmological constraints from BOSS with measurement of the void-galaxy cross-correlation %U http://arxiv.org/abs/1904.01030 %X We present a measurement of the anisotropic void-galaxy cross-correlation function in the CMASS galaxy sample of the BOSS DR12 data release. We perform a joint fit to the data for redshift space distortions (RSD) due to galaxy peculiar velocities and anisotropies due to the Alcock-Paczynski (AP) effect, for the first time using a velocity field reconstruction technique to remove the complicating effects of RSD in the void centre positions themselves. Fits to the void-galaxy function give a 1% measurement of the AP parameter combination $D_A(z)H(z)/c = 0.436\pm0.005$ at redshift $z=0.57$, where $D_A$ is the angular diameter distance and $H$ the Hubble parameter, exceeding the precision obtainable from baryon acoustic oscillations (BAO) by a factor of ~3.5 and free of systematic errors. From voids alone we also obtain a 12% measure of the growth rate, $f\sigma_8(z=0.57)=0.050\pm0.06$. The parameter degeneracies are orthogonal to those obtained from galaxy clustering. Combining void information with that from BAO and galaxy RSD in the same CMASS sample, we measure $D_A(0.57)/r_s=9.36\pm0.07$ (at 0.75% precision), $H(0.57)r_s=(14.03\pm0.16)\;10^3$ kms$^-1$Mpc$^-1$ (1.1%) and $f\sigma_8=0.450\pm0.019$ (4.2%), consistent with cosmic microwave background (CMB) measurements from Planck. These represent a factor ~2 improvement in precision over previous results through the inclusion of void information. Fitting a flat cosmological constant LCDM model to these results in combination with Planck CMB data, we find up to a 16% reduction in uncertainties on $H_0$ and $Ømega_m$ compared to use of the corresponding BOSS consensus values. Constraints on extended models with non-flat geometry and a dark energy of state that differs from $w=-1$ show an even greater improvement.

@misc{nadathur2019beyond, abstract = {We present a measurement of the anisotropic void-galaxy cross-correlation function in the CMASS galaxy sample of the BOSS DR12 data release. We perform a joint fit to the data for redshift space distortions (RSD) due to galaxy peculiar velocities and anisotropies due to the Alcock-Paczynski (AP) effect, for the first time using a velocity field reconstruction technique to remove the complicating effects of RSD in the void centre positions themselves. Fits to the void-galaxy function give a 1% measurement of the AP parameter combination $D_A(z)H(z)/c = 0.436\pm0.005$ at redshift $z=0.57$, where $D_A$ is the angular diameter distance and $H$ the Hubble parameter, exceeding the precision obtainable from baryon acoustic oscillations (BAO) by a factor of ~3.5 and free of systematic errors. From voids alone we also obtain a 12% measure of the growth rate, $f\sigma_8(z=0.57)=0.050\pm0.06$. The parameter degeneracies are orthogonal to those obtained from galaxy clustering. Combining void information with that from BAO and galaxy RSD in the same CMASS sample, we measure $D_A(0.57)/r_s=9.36\pm0.07$ (at 0.75% precision), $H(0.57)r_s=(14.03\pm0.16)\;10^3$ kms$^{-1}$Mpc$^{-1}$ (1.1%) and $f\sigma_8=0.450\pm0.019$ (4.2%), consistent with cosmic microwave background (CMB) measurements from Planck. These represent a factor ~2 improvement in precision over previous results through the inclusion of void information. Fitting a flat cosmological constant LCDM model to these results in combination with Planck CMB data, we find up to a 16% reduction in uncertainties on $H_0$ and $\Omega_m$ compared to use of the corresponding BOSS consensus values. Constraints on extended models with non-flat geometry and a dark energy of state that differs from $w=-1$ show an even greater improvement.}, added-at = {2019-04-03T06:13:51.000+0200}, author = {Nadathur, Seshadri and Carter, Paul M. and Percival, Will J. and Winther, Hans A. and Bautista, Julian}, biburl = {https://www.bibsonomy.org/bibtex/28f68b3beb46f8d37a0f88a6e64c7b5cb/gpkulkarni}, description = {Beyond BAO: improving cosmological constraints from BOSS with measurement of the void-galaxy cross-correlation}, interhash = {f08951c4b84b508034de0b6716eb9dd7}, intrahash = {8f68b3beb46f8d37a0f88a6e64c7b5cb}, keywords = {library}, note = {cite arxiv:1904.01030Comment: 22 pages, 16 figures. For the busy reader, Figures 13, 14 and 15 summarize the key cosmological information. Code used for reconstruction and void-finding is available at https://github.com/seshnadathur/Revolver}, timestamp = {2019-04-03T06:13:51.000+0200}, title = {Beyond BAO: improving cosmological constraints from BOSS with measurement of the void-galaxy cross-correlation}, url = {http://arxiv.org/abs/1904.01030}, year = 2019 }