اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدA Photometric and Kinematic Study of AWM 7
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We have measured redshifts and Kron-Cousins R-band magnitudes for a sample of galaxies in the poor cluster AWM 7. We have measured redshifts for 172 galaxies; 106 of these are cluster members. We determine the luminosity function from a photometric survey of the central 1.2 h^{-1} x 1.2 h^{-1} Mpc. The LF has a bump at the bright end and a faint-end slope of alpha = -1.37+-0.16, populated almost exclusively by absorption-line galaxies. The cluster velocity dispersion is lower in the core (sim 530 km/s) than at the outskirts (sim 680 km/s), consistent with the cooling flow seen in the X-ray. The cold core extends sim 150 h^{-1} kpc from the cluster center. The Kron-Cousins R-band mass-to-light ratio of the system is 650+-170 h M_odot/L_odot, substantially lower than previous optical determinations, but consistent with most previous X-ray determinations. We adopt H_0 = 100 h km/s/Mpc throughout this paper; at the mean cluster redshift, (5247+-76 km/s), 1 h^{-1} Mpc subtends 65$farcm$5.
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