摘要：We present a measurement of the baryon acoustic oscillation (BAO) scale at redshiftz = 2.35 from the three-dimensional correlation of Lyman-α(Lyα) forest absorption and quasars. The study uses 266 590 quasars in the redshift range 1.77 < z < 3.5 from the Sloan Digital Sky Survey (SDSS) Data Release 14 (DR14). The sample includes the first two years of observations by the SDSS-IV extended Baryon Oscillation Spectroscopic Survey (eBOSS), providing new quasars and re-observations of BOSS quasars for improved statistical precision. Statistics are further improved by including Lyαabsorption occurring in the Lyβwavelength band of the spectra. From the measured BAO peak position along and across the line of sight, we determined the Hubble distanceDHand the comoving angular diameter distanceDMrelative to the sound horizon at the drag epochrd:DH(z = 2.35)/rd = 9.20 ± 0.36 andDM(z = 2.35)/rd = 36.3 ± 1.8. These results are consistent at 1.5σwith the prediction of the best-fit spatially-flat cosmological model with the cosmological constant reported for thePlanck(2016) analysis of cosmic microwave background anisotropies. Combined with the Lyαauto-correlation measurement presented in a companion paper, the BAO measurements atz = 2.34 are within 1.7σof the predictions of this model.
关键词：enlarge-scale structure of Universedark energycosmological parameterscosmology: observationsquasars: absorption lines
