We present the large-scale clustering of emission line galaxies ( ELG ) from the Data Release 16 of the Sloan Digital Sky Survey IV extended Baryon Oscillation Spectroscopic Survey .
The ELG sample contains 173,736 galaxies covering 1,170 square degrees in the redshift range 0.6 < z < 1.1 .
We perform a BAO measurement from the post-reconstruction power spectrum monopole , and study redshift space distortions ( RSD ) in the first three multipoles .
Purely angular photometric systematics are mitigated by nulling angular signal in pixels of appropriate size .
Variations of the redshift distribution with photometric conditions are accounted for by splitting and measuring the radial selection function of the survey in regions of homogeneous imaging .
Both techniques result in integral constraints which we model consistently .
At the effective redshift z _ { eff } = 0.845 we measure D _ { V } ( z _ { eff } ) / r _ { drag } = 18.33 _ { -0.62 } ^ { +0.57 } , with D _ { V } the volume averaged distance and r _ { drag } the comoving sound horizon at the drag epoch .
In combination with the RSD measurement , at z _ { eff } = 0.85 we find f \sigma _ { 8 } ( z _ { eff } ) = 0.289 _ { -0.096 } ^ { +0.085 } , with f the growth rate of structure and \sigma _ { 8 } the normalisation of the linear power spectrum , D _ { H } ( z _ { eff } ) / r _ { drag } = 20.0 _ { -2.2 } ^ { +2.4 } and D _ { M } ( z _ { eff } ) / r _ { drag } = 19.17 \pm 0.99 with D _ { H } and D _ { M } the Hubble and comoving angular distances , respectively .
Quoted errors include statistical and systematic contributions .
We find good agreement with the results obtained in configuration space , thus allowing a consensus measurement of f \sigma _ { 8 } ( z _ { eff } ) = 0.315 \pm 0.095 , D _ { H } ( z _ { eff } ) / r _ { drag } = 19.6 _ { -2.1 } ^ { +2.2 } and D _ { M } ( z _ { eff } ) / r _ { drag } = 19.5 \pm 1.0 .
This measurement is in agreement with a flat \Lambda CDM model with Planck parameters .