A photometric study of the young open cluster NGC 1220 *,**
1
Dipartimento di Astronomia, Università di Padova, Vicolo Osservatorio 2, 35122 Padova, Italy e-mail: ortolani@pd.astro.it
2
Osservatorio Astronomico di Milano, Italy e-mail: covino@merate.mi.astro.it
3
Universidade Federal do Rio Grande do Sul, Dept. de Astronomia, CP 15051, Porto Alegre 91501-970, Brazil e-mail: bica@if.ufrgs.br
4
Universidade de Sao Paulo, Dept. de Astronomia, CP 3386, Sao Paulo 01060-970, Brazil e-mail: barbuy@astro.iag.usp.br
Corresponding author: G. Carraro, giovanni.carraro@unipd.it
Received:
9
April
2002
Accepted:
27
May
2002
We present UBV CCD observations obtained in the field
of the northern open cluster NGC 1220, for which little information
is available.
We provide also BV CCD photometry of a field 5′ northward
of NGC 1220 to take into account field star contamination.
We argue that NGC 1220 is a young compact open cluster, for
which we estimate a core radius in the range arcmin.
We identify 26 likely candidate members
with spectral type earlier than 
, down to 
mag
on the basis of the position in the two-colour Diagram
and in the Colour Magnitude Diagrams (CMDs).
By analyzing the distribution of these stars in the colour-colour
and CMDs, we find that
NGC 1220
has a reddening 
mag, is placed
pc distant from the Sun, and has an age
of about 60 Myrs. The cluster turns out to be located
about 120 pc above the Galactic plane, relatively high with respect
to its age.
Key words: open clusters and associations: individual: NGC 1220 / open clusters and associations: general
© ESO, 2002