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تسجيل مستخدم جديدMeasuring large-scale structure with the 2dF Galaxy Redshift Survey
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The 2dF Galaxy Redshift Survey is the first to measure more than 100,000 redshifts. This allows precise measurements of many of the key statistical measures of galaxy clustering, in particular redshift-space distortions and the large-scale power spectrum. This paper presents the current 2dFGRS results in these areas. Redshift-space distortions are detected with a high degree of significance, confirming the detailed Kaiser distortion from large-scale infall velocities, and measuring the distortion parameter beta = 0.43 +/- 0.07. The power spectrum is measured to < 10% accuracy for k > 0.02 h Mpc^-1, and is well fitted by a CDM model with Omega_m h = 0.20 +/- 0.03 and a baryon fraction of 0.15 +/- 0.07.
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