اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدLuminosity and Mass Function of the Galactic open cluster NGC 2422
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L. Prisinzano
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We present UBVRI photometry of the open cluster NGC 2422 (age $sim 10^8$ yr) down to a limiting magnitude $Vsimeq19$. These data are used to derive the Luminosity and Mass Functions and to study the cluster spatial distribution. By considering the color-magnitude diagram data and adopting a representative cluster main sequence, we obtained a list of candidate cluster members based on a photometric criterion. Using a reference field region and an iterative procedure, a correction for contaminating field stars has been derived in order to obtain the Luminosity and the Mass Functions in the $M=0.4-3.5 M_odot$ range. By fitting the spatial distribution, we infer that a non-negligible number of cluster stars lies outside our investigated region. We have estimated a correction to the Mass Function of the cluster in order to take into account the missing cluster stars. The Present Day Mass Function of gc2422 can be represented by a power-law of index $alpha = 3.07 pm0.08 $ (rms) -- the Salpeter Mass Function in this notation has index $alpha = 2.35$ -- in the mass range $ 0.9 leq M/M_odotleq 2.5 $. The index $alpha$ and the total mass of the cluster are very similar to those of the Pleiades.
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