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تسجيل مستخدم جديدBAO angular scale at z_eff = 0.11 with the SDSS blue galaxies
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We measure the transverse baryon acoustic oscillations (BAO) signal in the local Universe using a sample of blue galaxies from the Sloan Digital Sky Survey (SDSS) survey as a cosmological tracer. The method is weakly dependent on a cosmological model and is suitable for 2D analyses in thin redshift bins to investigate the SDSS data in the interval $z {in} [0.105, 0.115]$. We detect the transverse BAO signal ${theta}_{BAO} = 19.8^{deg} {pm} 1.05^{deg}$ at $z_{eff} = 0.11$, with a statistical significance of $2.2 {sigma}$. Additionally, we perform tests that confirm the robustness of this angular BAO signature. Supported by a large set of log-normal simulations, our error analyses include statistical and systematic contributions. In addition, considering the sound horizon scale calculated by the Planck Collaboration, $r_{s}^{Planck}$, and the ${theta}_{BAO}$ value obtained here, we obtain a measurement of the angular diameter distance $D_{A}(0.11) = 258.31 {pm} 13.71 ,Mpc/h$. Moreover, combining this ${theta}_{BAO}$ measurement at low redshift with other BAO angular scale data reported in the literature, we perform statistical analyses for the cosmological parameters of some Lambda cold dark matter (${Lambda}$CDM) type models.
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